U.S. patent application number 11/851232 was filed with the patent office on 2008-02-28 for paper, image-recording material support, and image-recording material.
This patent application is currently assigned to FUJIFILM Corporation. Invention is credited to Fuyuhiko Mori, Shigehisa TAMAGAWA.
Application Number | 20080047677 11/851232 |
Document ID | / |
Family ID | 33493950 |
Filed Date | 2008-02-28 |
United States Patent
Application |
20080047677 |
Kind Code |
A1 |
TAMAGAWA; Shigehisa ; et
al. |
February 28, 2008 |
PAPER, IMAGE-RECORDING MATERIAL SUPPORT, AND IMAGE-RECORDING
MATERIAL
Abstract
Paper and an image-recording material support which have high
surface planarity and excellent gloss are disclosed. Moreover, an
image-recording material is disclosed which uses the
image-recording material support and is capable of obtaining high
quality image. The paper includes raw paper. The paper satisfies at
least one of the following conditions (i) and (ii): (i) the paper
has an inner bonding strength of 160 mJ or more specified in Japan
Technical Association of the Pulp and Paper Industry No. 54, and an
average center surface roughness (SRa) on at least one face of the
paper is 0.9 .mu.m or less at a cutoff wavelength of 0.3 mm to 0.4
mm, and (ii) an Oken type smoothness S (second) on the at least one
face of the paper, and a density .rho. (g/cm.sup.3) of the paper
satisfy an expression S.sup.1/2/.rho..sup.3.gtoreq.15.
Inventors: |
TAMAGAWA; Shigehisa;
(Shizuoka, JP) ; Mori; Fuyuhiko; (Shizuoka,
JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W.
SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
FUJIFILM Corporation
|
Family ID: |
33493950 |
Appl. No.: |
11/851232 |
Filed: |
September 6, 2007 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10893886 |
Jul 20, 2004 |
|
|
|
11851232 |
Sep 6, 2007 |
|
|
|
Current U.S.
Class: |
162/135 |
Current CPC
Class: |
G03G 7/006 20130101;
B41M 5/41 20130101; D21H 21/18 20130101; B41M 5/508 20130101; D21H
25/14 20130101; D21H 19/82 20130101; D21H 19/44 20130101; G03C
1/775 20130101 |
Class at
Publication: |
162/135 |
International
Class: |
D21H 19/00 20060101
D21H019/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 23, 2003 |
JP |
2003-200599 |
Aug 1, 2003 |
JP |
2003-205472 |
Aug 1, 2003 |
JP |
2003-205473 |
Claims
1.-23. (canceled)
24. An image-recording material support, comprising: a raw paper
subjected to a press dry treatment; and a coat layer, wherein the
coat layer is formed by transferring a surface appearance of a
member with a smooth surface to at least a face of the raw paper
which face is subjected to the press dry treatment, wherein the
paper satisfies at least one of the following conditions (i) and
(ii): (i) the paper has an inner bonding strength, as defined in
Japan Technical Association of the Pulp and Paper Industry No. 54,
of 160 mJ or more, and an average center surface roughness on at
least one face of the paper is 0.9 .mu.m or less at a cutoff
wavelength of 0.3 mm to 0.4 mm, and (ii) an Oken type smoothness S
(second) on the at least one face of the paper, and a density .rho.
(g/cm.sup.3) of the paper satisfy an expression
S.sup.1/2/.rho..sup.3.gtoreq.5.
25. The image-recording material support according to claim 24,
wherein the smooth surface of the member is a mirror face of a
surface of a metal drum.
26. The image-recording material support according to claim 24,
wherein the coat layer is a cast coat layer.
27. The image-recording material support according to claim 24,
wherein the face subjected to the press dry treatment has an
average center surface roughness of 0.5 .mu.m or less at a cutoff
wavelength of 5 mm to 6 mm.
28. An image-recording material, comprising: an image-recording
material support comprising a raw paper subjected to a press dry
treatment; and a coat layer, wherein the coat layer is formed by
transferring a surface appearance of a member with a smooth surface
to at least a face of the raw paper which face is subjected to the
press dry treatment; and an image-recording layer disposed on the
image-recording material support, wherein the paper satisfies at
least one of the following conditions (i) and (ii): (i) the paper
has an inner bonding strength, as defined in Japan Technical
Association of the Pulp and Paper Industry No. 54, of 160 mJ or
more, and an average center surface roughness on at least one face
of the paper is 0.9 .mu.m or less at a cutoff wavelength of 0.3 mm
to 0.4 mm, and (ii) an Oken type smoothness S (second) on the at
least one face of the paper, and a density .rho. (g/cm.sup.3) of
the paper satisfy an expression
S.sup.1/2/.rho..sup.3.gtoreq.15.
29. The image-recording material according to claim 28, wherein the
image-recording material is selected from the group consisting of
an electrophotographic material, a heat sensitive material, an
inkjet-recording material, a sublimation transfer material, a
silver salt photographic material, and a heat transfer
material.
30. The image-recording material according to claim 28, wherein the
coat layer is a cast coat layer.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to paper having high surface
planarity and excellent gloss. Moreover, the present invention
relates to paper, an image-recording material support and an
image-recording material which are preferably used for an
electrophotographic material, a heat sensitive material, an
inkjet-recording material, a sublimation transfer material, a
silver salt photographic material, a heat transfer material, and
the like.
[0003] 2. Description of the Related Art
[0004] Conventionally, raw paper, synthetic paper, synthetic resin
sheet, coat paper, laminate paper, and the like are well known as a
support for various image-recording materials such as an
electrophotographic material, a heat sensitive material, an
inkjet-recording material, a sublimation transfer material, a
silver salt photographic material, a heat transfer material, and
the like. The above image-recording materials are used for
image-recording so as to obtain an image print having high quality
and high gloss. For this purpose, high planarity is needed for the
above image-recording materials, which also involves necessity for
high planarity of the support therefor.
[0005] For satisfying the above, various proposals have been made.
Japanese Patent Application Publication (JP-B) No. 06-55545
discloses an image-recording material support formed with an
intermediate layer (containing a white pigment) on raw paper
(containing a polyolefin synthetic pulp) having a density of 0.8
g/cm.sup.3 to 1.0 g/cm.sup.3. Japanese Patent Application Laid-Open
No. 11-11004 discloses an image-recording material support having
its inner bonding strength in a range from 0.9 kgcm to 2.2 kgcm and
having its friction coefficient in a range from 0.6 to 1.2. JP-A
No. 2001-301098 discloses an image-recording material support
having its average center surface roughness (SRa) of 0.75 .mu.m or
less measured at a cutoff wavelength of 5 mm to 7 mm. Moreover,
JP-B No. 2671154 discloses an image-recording material support
having pulp's average degree of polymerization of 800 or more and
having an inner bonding strength (of raw paper) in a range from 1.0
kgfcm to 2.0 kgfcm, and having pH (of face of raw paper) of 6.0 or
more.
[0006] When the image-recording material support has low strength,
use of the image-recording material having the support for
recording an image may cause a curl to an image print which is
outputted from a printer. In addition, the image-recording material
support having low planarity cannot form an image that has
high-quality and high gloss. Moreover, raw materials of the above
image-receiving material support are natural pulps such as
needle-leaf tree (hereinafter, when necessary, referred to as
"needle-leaf tree pulp"), broad-leaf (hereinafter, when necessary,
referred to as "broad-leaf tree pulp"), and the like, which are to
be produced by drying wet paper with a manual paper-making machine.
The image-recording material support thus produced may result in
deteriorated planarity which is attributable to shrink of pulp
fiber of the natural pulp (raw material) during the drying.
[0007] Any of the proposals disclosed in the above publications
cannot solve the problems sufficiently. Such an image-recording
material support is not proposed yet as having high planarity and
extremely excellent gloss. In addition, such an image-recording
material is not proposed yet as having a support therefor, having
high-quality image and excellent gloss after image-recording,
having high rigidity (stiffness), and causing a small curl.
Developments of the above are desired.
[0008] Conventionally, paper that is efficiently machined at high
speed is dried between many cylindrical driers by receiving a
tension in the longitudinal direction (paper-making direction)
while causing free shrinkage in the lateral direction. When being
subjected to a change in humidity, the thus machined paper is
likely to cause a large extension and/or shrinkage (telescopic
motion) in the lateral direction. With this, recordings such as
photographing with the above paper as a support may increase curl
in size, thus high-quality image cannot be formed.
[0009] To solve the above problem, JP-A No. 01-292354 (equivalent
of JP-B No. 2739160) discloses an electrophotographic transfer
paper having a small shrinkage factor, an excellent surface
smoothness, and causing a small curl, even when the paper is
subjected to a humidity change after drying. Specifically, the
above electrophotographic transfer paper is machined with so-called
a Yankee paper machine that can control drying shrinkage both in
the longitudinal and lateral directions, without receiving a
longitudinal tension during drying.
[0010] In this case, however, using the Yankee paper machine may
generally restrict many paper-making conditions such as freeness of
pulp paper material, paper-making speed, and the like.
[0011] On the other hand, a treatment in which a sheet of paper is
dried while being pressurized (hereinafter may be referred to as
press dry treatment) is expected to provide higher strength,
elasticity modulus, density and the like, and such process is
currently under development (Takuya Kadoya et al., Seishi Kagaku
"Science of paper-making" (Tokyo: Chugai Sangyo Chosakai, 1982),
pp. 174-177), Jun. 30, 1982 (Showa 57). In addition, JP-A No.
2000-500536 and JP-A No. 07-91829 (JP-B No. 3041754) propose web
pressure drying apparatuses which perform heat drying of a fiber
web with a press dry treatment and provide less restrictions when
used in a manufacturing line. In the above conventional
technologies, however, no specific press drying conditions and the
like are disclosed. JP-A No. 2000-500536 and JP-A No. 07-91829
(JP-B No. 3041754) only disclose the press drying apparatuses, with
no descriptions about relation between the press drying treatment
and image-recording material support.
[0012] On the other hand, conventionally, raw paper, synthetic
paper, a synthetic resin sheet, coat paper, laminate paper, and the
like are well known for use as an image-recording material support.
Among these, the coat paper and the laminate paper are
preferable.
[0013] Methods of producing the coat paper and the laminate paper
comprise a solvent coating method of applying to raw paper a
thermoplastic resin which is solved in an organic solvent, an
aqueous coating method of applying to raw paper a thermoplastic
resin which is made into a latex or an aqueous solution (varnish),
a dry laminate method of a thermoplastic resin, a melting extrusion
coating method, and the like.
[0014] However, the above solvent coating method that uses a
harmful organic solvent may cause harmful effect on the
environment. In the above aqueous coating method, water may swell
the raw paper when the latex or the aqueous solution (varnish) is
applied to the raw paper, thus losing smoothness of the raw paper,
which is so called a "return." Moreover, the aqueous coating method
is not applicable to resins which are less likely to be made into
latex or aqueous solution.
[0015] Summarizing the above, such an image-recording material
support and an image-recording material are not proposed as having
high surface smoothness and extremely excellent gloss, leaving an
issue of further improvement and development.
[0016] It is therefore an object of the present invention to
provide paper and an image-recording material support which have
high planarity and excellent gloss. It is another object of the
present invention to provide an image-recording material which has
high-quality image and high gloss after image-forming, and causes a
small curl.
SUMMARY OF THE INVENTION
[0017] Under the present invention, a paper according to its first
aspect comprises a raw paper. The paper satisfies the following:
the paper has an inner bonding strength of 160 mJ or more specified
in Japan Technical Association of the Pulp and Paper Industry No.
54, and an average center surface roughness on at least one face of
the paper is 0.9 .mu.m or less at a cutoff wavelength of 0.3 mm to
0.4 mm.
[0018] As a result, the paper according to its first aspect having
the inner bonding strength and the average center surface roughness
(SRa) respectively in the above certain ranges can have high
surface planarity and can be used preferably for an image-recording
material support.
[0019] Under the present invention, a paper according to its second
aspect comprises a raw paper. The paper satisfies the following: an
Oken type smoothness S (second) on the at least one face of the
paper, and a density .rho. (g/cm.sup.3) of the paper satisfy an
expression S.sup.1/2/.rho..sup.3.gtoreq.15.
[0020] As a result, the paper according to its second aspect
satisfying that the Oken type smoothness S and the density of the
paper satisfy the first expression can have high surface planarity
and an extremely excellent gloss and can be used preferably for the
image-recording material support.
[0021] Under the present invention, an image-recording material
support according to its first aspect comprises a paper which
comprises a raw paper. The paper satisfies at least one of the
following conditions (i) and (ii): (i) the paper has an inner
bonding strength of 160 mJ or more specified in Japan Technical
Association of the Pulp and Paper Industry No. 54, and an average
center surface roughness on at least one face of the paper is 0.9
.mu.m or less at a cutoff wavelength of 0.3 mm to 0.4 mm, and (ii)
an Oken type smoothness S (second) on the at least one face of the
paper, and a density .rho. (g/cm.sup.3) of the paper satisfy an
expression S.sup.1/2/.rho..sup.3.gtoreq.15.
[0022] As a result, the image-recording material support according
to its first aspect can have high surface planarity and an
extremely excellent gloss and can be used preferably for the
image-recording material.
[0023] Under the present invention, an image-recording material
support according to its second aspect comprises a raw paper
subjected to a press dry treatment; and a coat layer. The coat
layer is made by subjecting a face of the raw paper to a surface
treatment using a member with a smooth surface, the face of the raw
paper being to be formed with an image-recording layer.
[0024] With the press dry treatment, density, elasticity modulus,
tensile strength, strength and the like can be improved. Moreover,
a base paper which was subjected to the press dry treatment is
formed with the coat layer, and the coat layer is allowed to abut
on the smooth surface, for transferring the surface appearance.
[0025] As a result, the image-recording material support according
to its second aspect can have high surface planarity and an
extremely excellent gloss.
[0026] An image-recording material under the present invention
comprises a support; and an image-recording layer disposed on the
support. The image-recording material uses, as the support, the
image-recording material support according to at least one of its
first aspect and its second aspect described above.
[0027] As a result, high-quality image can be provided for the
image-recording materials for any of the applications including an
electrophotographic material (electrophotographic image-receiving
material), a heat sensitive material (heat sensitive coloring
recording material), an inkjet-recording material, a sublimation
transfer material (sublimation transfer image-receiving material),
a silver salt photographic material (silver halide photographic
photosensitive material), and a heat transfer material (heat
transfer image-receiving material).
[0028] Further objects, features and advantages of the present
invention will become apparent from the following description of
the preferred embodiments with reference to the attached
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 shows a schematic of an example of a press dry
treatment apparatus under the present invention.
[0030] FIG. 2 shows a schematic of an example of a press dry
treatment apparatus used for a production line under the present
invention.
[0031] FIG. 3 shows a schematic of an example of a wet cast method
under the present invention.
[0032] FIG. 4 shows an example of a gelatinization cast method
under the present invention.
[0033] FIG. 5 shows an example of a rewet cast method under the
present invention.
[0034] FIG. 6 shows a schematic of a fixing belt apparatus of a
printer used for examples under the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(Paper)
[0035] Under the present invention, a paper according to its first
aspect comprises a raw paper. The paper has an inner bonding
strength of 160 mJ or more specified in Japan Technical Association
of the Pulp and Paper Industry (hereinafter referred to as "JAPAN
TAPPI") No. 54, and an average center surface roughness (SRa) on at
least one face of the paper is 0.9 .mu.m or less at a cutoff
wavelength of 0.3 mm to 0.4 mm.
[0036] The inner bonding strength is the one that is specified in
JAPAN TAPPI No. 54.
[0037] As long as being 160 mJ or more, the inner bonding strength
is not particularly limited, and can be suitably selected according
to the object. For example, the inner bonding strength is preferred
to be 200 mJ or more, and more preferably 216 mJ or more.
[0038] The average center surface roughness (SRa) can be obtained
by scanning three-dimensionally a plane having a certain roughness,
and therefore is different from an average center line roughness
(Ra) that can be obtained by scanning a linear roughness of a
plane. As the roughness at the cutoff wavelength of 0.3 mm to 0.4
mm decreases, the surface may appear flatter and flatter. An
apparatus for measuring the average center surface roughness (SRa)
is not particularly limited, and can be suitably selected according
to the object. For example, SURFCOM 570A-3DF (made by Tokyo
Seimitsu) can be used for measuring the average center surface
roughness (SRa) at the cutoff wavelength of 0.3 mm to 0.4 mm, based
on the following measuring condition and analysis condition.
--Measuring Condition and Analysis Condition--
[0039] Scanning direction: MD direction of sample.
[0040] Measuring length: Machining paper direction (X-direction) 50
mm, and perpendicular direction (Y-direction) thereto 30 mm.
[0041] Measuring pitch: X-direction 0.1 mm, Y-direction 0.1 mm.
[0042] Scanning speed: 30 mm/sec.
[0043] Band pass filter: 0.3 mm to 0.4 mm.
[0044] Herein, as long as being 0.9 .mu.m or less at the cutoff
wavelength of 0.3 mm to 0.4 mm, the average center surface
roughness (SRa) is not particularly limited, and can be suitably
selected according to the object. For example, the average center
surface roughness (SRa) is preferred to be 0.8 .mu.m or less, and
more preferably 0.75 .mu.m or less.
[0045] As long as the average center surface roughness (SRa) is
satisfied on at least a first face of the paper, it is not
particularly limited. When the paper is used as an image-recording
material support, however, the average center surface roughness
(SRa) is to be preferably satisfied on the side (of the
image-recording material support) to be formed with an
image-recording layer.
[0046] Under the present invention, a paper according to its second
aspect comprises a raw paper. An Oken type smoothness S (second) on
at least one face of the paper, and a density .rho. (g/cm.sup.3) of
the paper satisfy an expression
S.sup.1/2/.rho..sup.3.gtoreq.15.
[0047] Hereinafter, the value calculated by the above expression
S.sup.1/2/.rho..sup.3 are, as the case may be, referred to as "H
index."
[0048] The Oken type smoothness S (second) is defined based on the
method B (measuring method) specified in JAPAN TAPPI No. 5, and is
obtained for example, by a smoothness (roughness) test using an
Oken type smoothness air-transparency tester.
[0049] As long as the above is satisfied, the Oken type smoothness
S (second) is not particularly limited, and can be suitably
selected according to the object. For example, the Oken type
smoothness S is preferred to be 100 sec or more, and more
preferably 150 sec or more. An upper limit of the Oken type
smoothness S is not particularly limited, ordinarily preferred to
be 600 sec or less, and more preferably 500 sec or less.
[0050] A face having the Oken type smoothness S (second) satisfying
the above can be only on one side of the paper, or on both sides of
the paper. When the paper is used as an image-recording material
support, however, the Oken type smoothness S (second) is preferably
satisfied on the side to be formed with an image-recording layer,
from the viewpoint of forming high-quality image.
[0051] As long as the above is satisfied, the density .rho.
(g/cm.sup.3) is not particularly limited, and can be suitably
selected according to the object. For example, the density .rho.
(g/cm.sup.3) is preferred to be 0.85 g/cm.sup.3 to 1.05 g/cm.sup.3.
The density less than 0.85 g/cm.sup.3 may cause insufficient
planarity, and more than 1.05 g/cm.sup.3 may cause an insufficient
rigidity (stiffness).
[0052] As long as being 15 or more, the H index calculated by the
above expression S.sup.1/2/.rho..sup.3 is not particularly limited
and can be suitably selected according to the object. For example,
the H index is preferred to be 16 or more, and more preferably 17
or more. The H index less than 15 may cause an insufficiency to at
least one of the planarity and the rigidity (stiffness). An upper
limit of the H index is not particularly specified, and can be
suitably selected according to the object. For example, the upper
limit of the H index is preferred to be 23 or less, and more
preferably 19 or less.
[0053] Moreover, an Oken type smoothness S.sub.1 (second) on a face
of the paper that is subjected to a press dry treatment, and a
density .rho..sub.1 (g/cm.sup.3) of the paper after the press dry
treatment satisfy an expression
S.sup.1/2/.rho..sub.1.sup.3.gtoreq.15.
[0054] The paper is not particularly limited, and can be suitably
selected according to the object. For example, the paper can be raw
paper, synthetic paper, a synthetic resin sheet, coat paper,
laminate paper, and the like.
[0055] The above raw paper is not particularly limited, and can be
suitably selected according to the object. Specifically, the raw
paper can be preferred to be those described on page 223 to page
224 of Society of Photographic Science and Technology of Japan
"Fundamentals of Photography (shashin kougaku no kiso)--Silver Salt
Photograph" published by Corona (Showa 54 [1979]).
[0056] As long as being a known material used for the support, the
raw paper is not particularly limited, and can be suitably selected
according to the object. Examples of the raw paper include natural
pulps such as needle-leaf tree pulp, broad-leaf tree pulp and the
like, a mixture of the above natural pulp(s) with a synthetic
pulp(s), and the like.
[0057] The pulp usable for a raw material of the raw paper is
preferred to be the broad-leaf tree pulp, from the viewpoint of
simultaneously improving planarity, dimension stability and the
like of the raw paper, in a good balance and to a sufficient level.
The needle-leaf tree is, however, also usable.
[0058] Examples of the broad-leaf tree pulps include broad-leaf
tree bleached kraft pulp (LBKP), broad-leaf tree sulfite pulp
(LBSP) and the like. Among these, the broad-leaf tree bleached
kraft pulp (LBKP) is preferable.
[0059] A content of the broad-leaf tree pulp relative to the paper
is not particularly limited, and can be suitably selected according
to the object. For example, the content is preferred to be 50% by
mass or more, more preferably 60% by mass or more, and still more
preferably 75% by mass or more.
[0060] Examples of the needle-leaf tree pulp include needle-leaf
tree bleached kraft pulp (NBKP) and the like.
[0061] As the above pulp, it is preferable to use mainly a
broad-leaf tree pulp that originally has a short fiber length.
[0062] A beater, a refiner or the like can be used for beating the
pulp. When necessary, various types of additives can be added to a
pulp slurry (hereinafter referred to as "pulp paper material" as
the case may be) which can be obtained after beating the pulp.
Examples of the additives include filling material, dry paper
reinforcer, sizing agent, wet paper reinforcer, fixing agent, pH
regulator, other agents and the like.
[0063] Examples of the filling materials include calcium carbonate,
clay, white clay, kaolin, white earth, talc, titanium oxide,
diatomaceous earth, barium sulfate, aluminum hydroxide, magnesium
hydroxide and the like.
[0064] Examples of the dry paper reinforcers include cationic
starch, cationic polyacrylamide, anionic polyacrylamide, amphoteric
polyacrylamide, carboxy-modified polyvinyl alcohol and the
like.
[0065] Examples of the sizing agents include rosin derivatives such
as aliphatic salts, rosin, maleic rosin or the like; paraffin wax,
alkyl ketene dimer, alkenyl succinic anhydride (ASA), epoxy
aliphatic amide, and the like.
[0066] Examples of the wet paper reinforcers include polyamine
polyamide epichlorohydrin, melamine resin, urea resin, epoxy
polyamide resin and the like.
[0067] Examples of the fixing agents include polyfunctional metal
salts such as aluminum sulfate, aluminum chloride, or the like;
cationic polymers such as cationic starch, or the like.
[0068] Examples of the pH regulators include caustic soda, sodium
carbonate and the like.
[0069] Examples of other agents include defoaming agents, dyes,
slime control agents, fluorescent whitening agents and the
like.
[0070] Moreover, softeners can also be added when necessary. For
the softeners, ones which are disclosed on pp. 554-555 of Paper and
Paper Treatment Manual (Shiyaku Time Co., Ltd.) (1980) and the like
can be used, for example.
[0071] Each of the above additives and the like can be used either
alone or in combination of two or more. The amount of each of the
additives into the pulp paper material is not particularly limited,
and can be suitably selected according to the object, 0.1% by mass
to 1.0% by mass is preferred ordinarily.
[0072] Moreover, the pulp paper material which is the pulp slurry
to which the various types of additives are added if necessary is
to be machined by using paper-making machines such as a manual
paper-making machine, a long-net paper-making machine, a round-net
paper-making machine, a twin-wire machine, a combination machine,
and thereafter is dried for preparing the raw paper. When
necessary, either before or after the drying, a surface sizing
treatment can be carried out.
[0073] Examples of surface sizing treatment liquids used for the
surface sizing treatment include at least one metal salt selected
from alkaline metal salt and alkaline earth metal salt,
water-soluble high molecular compound, fluorescent whitening agent,
waterproof substance, pigment, dye and the like.
[0074] As the at least one the metal salt selected from the
alkaline metal salt and the alkaline earth metal salt, those
described above can be used.
[0075] The water-soluble high molecular compound is not
particularly limited, and can be suitably selected according to the
object. Examples of the water-soluble high molecular compounds
include polyvinyl alcohol, carboxy-modified polyvinyl alcohol,
carboxymethyl cellulose, hydroxyethyl cellulose, cellulose sulfate,
polyethylene oxide, gelatin, cationic starch, casein, sodium
polyacrylate, sodium salt of styrene-maleic acid anhydride
copolymer, sodium polystyrene sulfonate and the like. Among these,
polyvinyl alcohol, carboxy-modified polyvinyl alcohol,
carboxymethyl cellulose, hydroxyethyl cellulose, cellulose sulfate,
polyethylene oxide, and gelatin are preferable, and particularly
polyvinyl alcohol (PVA) is more preferable.
[0076] A content of the water-soluble high molecular compound is
preferably 0.5 g/m.sup.2 to 2 g/m.sup.2.
[0077] Examples of the fluorescent whitening agents include
stilbene compounds, coumarin compounds, biphenyl compounds,
benzo-oxazoline compounds, naphthalimide compounds, pyrazoline
compounds, carbostyryl compounds, carbostyryl compounds, diamino
stilbene disulfonic acid derivative, imidazole derivative, coumarin
derivative, triazole derivative, carbazole derivative, pyridine
derivative, naphthalic acid derivative, imidazolone derivative and
the like. Among these, stilbene compound is preferable.
[0078] A content of the florescent whitening agent is not
particularly limited, and 0.01% by mass to 0.5% by mass is
preferable, more preferably 0.02% by mass to 0.2% by mass.
[0079] Examples of the waterproof materials include latex emulsions
such as styrene-butadiene copolymer, ethylene-vinyl acetate
copolymer, polyethylene, vinylidene chloride copolymer or the like;
polyamide polyamine epichlorohydrin and the like.
[0080] Examples of the pigments include calcium carbonate, clay,
kaolin, talc, barium sulfate, titanium oxide and the like.
[0081] As for the above-mentioned raw paper, to improve the
rigidity (stiffness) and dimension stability of the image-recording
material support, it is preferred that the ratio (Ea/Eb) of the
longitudinal Young's modulus (Ea) to the lateral Young's modulus
(Eb) is within a range from 1.5 to 2.0. When the ratio (Ea/Eb) is
less than 1.5 or more than 2.0, the rigidity (stiffness) and
dimension stability of the image-recording material support tend to
deteriorate, and may cause inconveniences to traveling property
during transportation.
[0082] It has been found that, in general, the "rigidity
(stiffness)" of the paper differs based on differences in the way
the paper is beaten, and the elasticity modulus of paper from
paper-making after beating can be used as an important indication
of the "rigidity (stiffness)" of the paper. The elasticity modulus
of the paper can be calculated from the following equation by using
the relation of the density and the dynamic modulus which shows the
physical properties of a viscoelastic object, and by measuring the
velocity of sound propagation in the paper using an ultrasonic
oscillator. E=.rho.c.sup.2(1-n.sup.2)
[0083] where "E" represents dynamic modulus; ".rho." represents
density; "c" represents the velocity of sound in paper; and "n"
represents Poisson's ratio.
[0084] As n=0.2 or so in a case of ordinary paper, there is not
much difference in the calculation, even when the calculation is
performed by the following equation: E=.rho.c.sup.2
[0085] Accordingly, when the density of the paper and acoustic
velocity can be measured, the elasticity modulus can easily be
calculated. In the above equation, when measuring acoustic
velocity, various instruments known in the art may be used, such as
a Sonic Tester SST-110 (Nomura Shoji Co., Ltd.) or the like.
[0086] The thickness of the raw paper is not particularly limited,
and can be suitably selected according to the object, and it is
preferably 30 .mu.m to 500 .mu.m, and more preferably 50 .mu.m to
300 .mu.m, and still more preferably 100 .mu.m to 250 .mu.m. The
basis weight of the raw paper is not particularly limited, and can
be suitably selected according to the object, and for example, it
is preferably from 50 g/m.sup.2 to 250 g/m.sup.2, and more
preferably from 100 g/m.sup.2 to 200 g/m.sup.2.
--Press Dry Treatment--
[0087] The press dry treatment is not particularly limited and may
be suitably selected according to the object, provided that it can
heat and dry the pulp paper material while pressing it to soften
paper fibers and allow the fibers to come close to each other. For
example, the pulp paper material is dehydrated using a manual
paper-making machine and then its water content before press dry
treatment is adjusted to 30% to 70% using a wet press apparatus or
the like, thereby forming a sheet of raw paper. Then, at a drying
temperature from 100.degree. C. to 200.degree. C., a press dry
treatment is performed on the raw paper, specifically, on a side
(of the raw paper whose water content is adjusted) to be formed
with an image-recording layer.
[0088] Water content of the raw paper (wet paper) before the press
drying treatment is preferably 30% to 70%, more preferably 40% to
60%.
[0089] The water content of the raw paper after the press drying
treatment is not particularly limited, and may be suitably selected
according to the object, preferably it is 10% or less, and more
preferably 3% to 8%.
[0090] The drying temperature on the raw paper's side to be formed
with the image-recording layer is preferably from 100.degree. C. to
200.degree. C., more preferably from 110.degree. C. to 180.degree.
C. When the above drying temperature is lower than 100.degree. C.,
a sufficient amount of water does not evaporate and bonding among
fibers becomes weak, which sometimes results in unfavorable paper
force. When it is higher than 200.degree. C., sizing property and
planarity may become insufficient due to the relationship with
additives.
[0091] The pressure of the press dry treatment is preferably from
0.05 MPa to 1.5 MPa, and more preferably from 0.05 MPa to 0.5
MPa.
[0092] The pressure of the press dry treatment less than 0.05 MPa
may make the planarity insufficient due to reduced fluidity of the
resin, while more than 1.5 MPa may cause partly uneven density.
[0093] The density of the raw paper after the press dry treatment
is preferably 0.85 g/cm.sup.3 to 1.05 g/cm.sup.3, and more
preferably 0.9 g/cm.sup.3 to 1.05 g/cm.sup.3. The above density of
the raw paper less than 0.85 g/cm.sup.3 may make the planarity
insufficient.
[0094] The apparatus with which the press dry treatment is
performed is not particularly limited and may be suitably selected
according to the object. For example, a press dry treatment
apparatus 100 based on Condebelt drying technique as shown in FIG.
1 is preferable as an apparatus which is not incorporated in a
production line and oriented towards laboratory use.
[0095] The press dry treatment apparatus 100 has an upper plate 42,
a lower plate 43, a jacket 44 provided between the upper plate 42
and the lower plate 43, and one or more other members when
necessary.
[0096] Drying with the press dry treatment apparatus 100 is
performed by placing a sheet of wet paper (not shown) which has
been prepared by dehydrating pulp paper material with a manual
paper-making machine and a wet press apparatus or the like in a
jacket 44 which is impermeable to air; and thermally drying and
pressuring the sheet with the upper plate 42 and lower plate 43 the
temperatures of which are each controlled by electrically heated
oil 47. During pressure drying, water vapor and the like which are
generated at the wet paper are removed by a vacuum tank 49.
Pressuring is performed by applying pressure to the lower plate 43
with a pressing unit 48 using hydraulic oil 45. Further, during
pressure drying, cooling water 46 is configured to flow through the
apparatus.
[0097] For example, STATIC CONDEBELT (manufactured by VALMET) which
is a static press dry equipment may be used as one of such press
dry treatment apparatuses.
[0098] On the other hand, when the press dry treatment is to be
incorporated into a production line so that it can be performed
continuously, a press dry treatment apparatus 200 as shown in FIG.
2 is preferable.
[0099] Referring to FIG. 2, the press dry treatment apparatus 200
includes a first endless belt 38 and a second endless belt 39 which
are impermeable to air and conduct heat well, a first set of
turning rollers 51 and 52 around which the first endless belt 38 is
arranged to turn, and a second set of turning rollers 53 and 54
around which the second endless belt 39 is arranged to turn.
[0100] The first endless belt 38 and the second endless belt 39 are
arranged in such a way that they run part of the way parallel with
each other so that they form a drying zone between themselves.
[0101] A heating chamber 55 heats the first endless belt 38, and a
cooling chamber 56 cools the second endless belt 39.
[0102] Then, dehydrated wet paper 40 and at least one fabric 41
which forms an endless loop are introduced between the first
endless belt 38 and the second endless belt 39 in such a way that
the dehydrated wet paper 40 is in contact with the heated first
endless belt 38 and the fabric 41 is positioned between the
dehydrated wet paper 40 and both of the cooled second endless belt
39 and guide rollers and accordingly the wet paper 40 is pressure
dried.
[0103] The details of the press dry treatment apparatus 200 are
described in JP-A No. 2000-500536.
[0104] According to this press dry treatment apparatus, it is
possible to achieve a good press dry result more efficiently than
with conventional ones.
[0105] By the press dry treatment described above, the sheet of raw
paper has better density, elasticity modulus, tensile strength,
strength and the like so as to provide an image-recording material
support which is excellent in dimension stability and planarity and
with which curl is less likely to occur. Accordingly, by using the
above image-recording material support, it is possible to provide
high-quality images.
[0106] To a cast coat layer which is provided on the raw paper
after the press dry treatment, when necessary, a calender treatment
by means of a super calender and the like may be carried out.
--Calender Treatment--
[0107] The paper is preferred to be subjected to the calender
treatment after the press dry treatment.
[0108] The calender treatment is not particularly limited, and can
be suitably selected according to the object. In this case,
however, a high temperature soft calender treatment is preferred,
and temperature of the surface of the metal roll is preferably
110.degree. C. or more, more preferably 150.degree. C. or more, and
still more preferably 250.degree. C. or more. An upper limit of the
temperature is for example 300.degree. C.
[0109] Carrying out the calender treatment can obtain paper having
high gloss.
[0110] As described above, the paper under the present invention
has high planarity and excellent gloss, and can be used for various
applications. Particularly, the paper is preferably to be used for
the image-recording material support described below.
(Image-Recording Material Support)
[0111] Under the present invention, an image-recording material
support according to its first aspect comprises a paper which
comprises a raw paper. The paper satisfies at least one of the
following conditions (i) and (ii): (i) the paper has an inner
bonding strength of 160 mJ or more specified in Japan Technical
Association of the Pulp and Paper Industry No. 54, and an average
center surface roughness on at least one face of the paper is 0.9
.mu.m or less at a cutoff wavelength of 0.3 mm to 0.4 mm, and (ii)
an Oken type smoothness S (second) on the at least one face of the
paper, and a density .rho. (g/cm.sup.3) of the paper satisfy an
expression S.sup.1/2/.rho..sup.3.gtoreq.15.
[0112] As described above, the image-recording material support
according to its first aspect is preferably to be subjected to at
least one of the press dry treatment and the calender
treatment.
[0113] Under the present invention, an image-recording material
support according to its second aspect comprises a raw paper
subjected to a press dry treatment to thereby form a press-dried
face; and a coat layer. The coat layer is made by subjecting the
press-dried face of the raw paper to a surface treatment using a
member with a smooth surface.
[0114] Moreover, the image-recording material support according to
its second aspect comprises another layer, when necessary.
--Formation of Coat Layer and Transfer of Surface Appearance--
[0115] For formation of coat layer and transfer of surface
appearance, a method is proposed of abutting the coat layer to a
smooth surface of a member, to thereby transfer the surface
appearance. In this case, the smooth surface of the member is
preferred to be a mirror face of a metal drum.
[0116] The method for transferring the surface appearance of the
smooth surface to the coat layer is not particularly limited, and
can be suitably selected according to the object. For example, a
cast coat method is preferable. In the cast coat method, a cast
coating solution is to be applied to the raw paper which was
subjected to the press dry treatment, then, in a state that the
entire coat layer or the surface of the coat layer is wet or
plastic, the coat layer is to be crimped to a heated finished
surface of the metal cast drum. With this, drying the coat layer
and the photographing of the finished surface can be simultaneously
achieved.
[0117] The cast coast method is not particularly limited, and can
be suitably selected according to the object, examples including
wet cast method, gelatinization cast method, rewet cast method and
the like. Each of the above methods is common in that photographing
of the surface appearance of the cast drum with the mirror face can
obtain a high-gloss surface of the coat layer. The above methods
have the following characteristics, respectively, up to a process
that the cast coating solution applied to the raw paper is crimped
to the cast drum.
[0118] In FIG. 3, the wet cast method (direct method) is shown. In
a state that the cast coating solution applied to the raw paper
(which was subjected to the press dry treatment) is not dried at
all, the cast coating solution is crimped to a cast drum 10 (with a
mirror face), to thereby transfer the surface appearance of the
cast drum 10.
[0119] In FIG. 4, the gelatinization cast method is shown. The cast
coating solution applied to the raw paper (which was subjected to
the press dry treatment) is treated with a coagulation liquid, then
the cast coating solution is gelatinized (free from fluidity) and
is crimped to the cast drum 10 (with the mirror face), to thereby
transfer the surface appearance of the cast drum 10.
[0120] In FIG. 5, the rewet cast method is shown. The cast coating
solution applied to the raw paper (which was subjected to the press
dry treatment) is dried in advance, then a rewet liquid having a
main component of water is applied to a dried coat face to thereby
make a coat material swelled or plasticized, then the cast coat
liquid is crimped to the cast drum 10 (with the mirror face) and is
dried, to thereby obtain cast coat paper which is smooth and highly
glossy. Compared with the wet cast method and the gelatinization
cast method, the rewet cast method is good in that the productivity
is high.
[0121] In each of the wet cast method, the gelatinization cast
method and the rewet cast method, the cast drum is the one that is
made of metal having a cylindrical outer periphery mirror-machined,
and ordinarily is heated at 80.degree. C. to 150.degree. C. for
use.
[0122] The coat layer to be disposed at least a first face of the
raw paper which was subjected to the press dry treatment is
obtained by applying thereto the cast coating solution (including
at least a pigment and a binder) and drying it.
[0123] The pigment is not particularly limited, and can be suitably
selected according to the object. Examples of the pigments include
silica, alumina, calcium carbonate, magnesium carbonate, barium
sulfate, aluminum hydroxide, kaolin, talc, clay, titanium dioxide,
zinc oxide, various plastic pigments and the like, to be used
either alone or in combination of two ore more.
[0124] The binder is not particularly limited, and can be suitably
selected according to the object. Examples of the binder include
starches such as oxidized starch, esterified starch and the like;
cellulose derivatives such as carboxymethyl cellulose, hydroxyethyl
cellulose and the like; proteins such as gelatin, casein, soybean
albumin and the like; polyvinyl alcohol, polyvinyl pyrrolidone,
acrylic resin, styrene-acrylic resin, vinyl acetate resin, vinyl
chloride resin, urea resin, urethane resin, alkyd resin, polyester
resin, polycarbonate resin, styrene-butadiene latex and derivatives
thereof. The above binders can be used either alone or in
combination of two or more. Use of a plural types of the binders in
combination may have proper variations according to property of the
cast coating solution, prescription, application of the cast coat
paper and the like.
[0125] A content of the binder is preferably 1% by mass to 10% by
mass (solid conversion) to the entire amount of the coating
solution, and more preferably 3% by mass to 8% by mass.
[0126] Blend ratio of the pigment to the binder (P/B=dry blend mass
part number of pigment/dry blend mass part number of binder) is not
particularly limited, and can be suitably selected according to the
object, preferably 1.5 to 15, and more preferably 3 to 7. Greater
blend ratio may lose the smoothness.
[0127] To the cast coating solution, the following assistants can
be applied when necessary: known assistants such as pigment
dispersant, water holding agent, thickener, antifoaming agent,
preservative, colorant, waterproof agent, wetting agent,
plasticizer, fluorescent paint, ultraviolet absorber, oxidation
inhibitor, cationic high molecular electrolyte and the like.
[0128] Examples of coaters for the cast coating solution include
blade coater, air knife coater, roll coater, comma coater (made by
Kobayashi Engineering Works, Ltd.), brush coater, squeeze coater,
curtain oater, kiss coater, bar coater, gravure coater and the
like.
[0129] The amount of the cast coating solution (solid conversion)
is preferably 2 g/m.sup.2 to 50 g/m.sup.2, more preferably 3
g/m.sup.2 to 30 g/m.sup.2.
[0130] Examples of the methods for drying the coat layer include
air floating drier, infrared drier, cylinder drier and the
like.
[0131] In the case that a cast coat layer is formed by the rewet
cast method, examples of the additives of rewet liquids include
ammonium salt, polyamide resin, phosphor compound such as
hexametaphosphate, amide compound, fluoride, zinc sulfate, calcium
formate, and the like.
[0132] In the case that the cast coat layer is to be formed by the
coagulation method, examples of coagulants added to the coagulation
liquid include salts such as formic acid, acetic acid, citric acid,
tartaric acid, lactic acid, hydrochloric acid, sulfuric acid,
carbonic acid with calcium, zinc, magnesium, sodium, potassium,
barium, lead, cadmium, ammonium, and the like; boric acids such as
borax; and the like. The above coagulants can be used either alone
or in combination of two or more.
[0133] The cast coat layer can be formed on one side of the raw
paper, or on both sides of the raw paper. The number of cast coat
layers is not limited to one, instead, a multiple-layer structure
is allowed.
[0134] The image-recording material support under the present
invention is, as described above, so constituted that the coat
layer is formed at least on the side (of the raw paper which was
subjected to the press dry treatment) to be formed with the
image-recording layer, and the coat layer is allowed to abut on the
smooth surface to thereby transfer the surface appearance. With
this, the image-recording material support is excellent in surface
smoothness and is extremely excellent in gloss.
[0135] The average center surface roughness (SRa) on the side (of
the image-recording material support) to be formed with the
image-recording layer is preferably 0.5 .mu.m or less at a cutoff
wavelength of 5 mm to 6 mm, more preferably 0.1 .mu.m to 0.4 .mu.m.
The average center surface roughness (SRa) over 0.5 .mu.m may cause
an insufficient planarity after the coating.
[0136] Herein, the average center surface roughness (SRa) can be
obtained by scanning three-dimensionally a plane having a certain
roughness, and therefore is different from an average center line
roughness (Ra) that can be obtained by scanning a linear roughness
of a plane. For example, SURFCOM 570A-3DF (made by Tokyo Seimitsu)
can be used for measuring the average center surface roughness
(SRa) at the cutoff wavelength of 5 mm to 6 mm, based on the
following measuring condition and analysis condition.
--Measuring Condition and Analysis Condition--
[0137] Scanning direction: MD direction of sample.
[0138] Measuring length: Machining paper direction (X-direction) 50
mm, and perpendicular direction (Y-direction) thereto 30 mm.
[0139] Measuring pitch: X-direction 0.1 mm, Y-direction 0.1 mm.
[0140] Scanning speed: 30 mm/sec.
[0141] Band pass filter: 5 mm to 6 mm.
[0142] In terms of surface smoothness and gloss of the
image-recording material support: specifically, 20% or more at
20-degree gloss is preferable, and 40% or more at 20-degree gloss
is more preferable. The gloss less than 20% may cause an
insufficient gloss after the image formation.
[0143] The above 20-degree gloss can be measured based on JIS
Z8741.
[0144] In terms of waterproof of the image-recording material
support: specifically, Cobb sizing water absorbency (30 sec) is
preferred to be 10 g/m.sup.2 or less, more preferably 5 g/m.sup.2
or less, and still more preferably 4 g/m.sup.2 or less.
[0145] The above Cobb sizing water absorbency can be obtained by
measuring the amount of water absorbency when a pure water has a
contact with a sample for 30 seconds pursuant to JIS P8140.
(Image-Recording Material)
[0146] The image-recording material under the present invention
includes at least a support and an image-recording layer formed on
the support. The above support is the image-recording material
support under the present invention.
[0147] The image-recording material differs with the use and type
thereof, and examples include an electrophotographic material, heat
sensitive material, inkjet-recording material, sublimation transfer
material, silver salt photographic material, heat transfer material
and the like.
<Electrophotographic Material>
[0148] An electrophotographic material includes an image-recording
material support and at least one toner image-receiving layer which
is disposed on at least one surface of this support under the
present invention. When necessary, the electrophotographic material
may further include other layers which may be suitably selected.
Examples of the other layers include a surface protection layer, an
intermediate layer, an underlayer, a cushion layer, a static
control (prevention) layer, a reflection layer, a color tone
adjusting layer, a storage property improvement layer, an antistick
layer, an anticurl layer, a smoothing layer and the like. These
layers may have a single-layer structure or a laminated
structure.
[Toner Image-Receiving Layer]
[0149] The toner image-receiving layer receives a color toner or a
black toner and forms an image. The toner image-receiving layer has
a function to receive toner which forms an image from a developing
drum or an intermediate transfer by (static) electricity or
pressure in a transferring step, and to fix the image by heat or
pressure in a fixing step.
[0150] The material of the toner image-receiving layer contains at
least a polymer, when necessary, and various additives to be added
for improving thermodynamic properties of the toner image-receiving
layer. Examples of the additives include releasing agent,
plasticizer, filler, cross-linking agent, charge control agent,
emulsifier, dispersant and the like.
--Polymer For Toner Image-Receiving Layer--
[0151] Polymer for toner image-receiving layer is not particularly
limited, and can be suitably selected according to the object,
examples thereof including (1) polyolefin resin, (2) polystyrene
resin, (3) acrylic resin, (4) polyvinyl acetate or derivatives
thereof, (5) polyamide resin, (6) polyester resin, (7)
polycarbonate resin, (8) polyether resin (or acetal resin), (9)
other resins. The above polymers may be used either alone or in
combination of two or more. Among the above, in terms of embedding
of the toner, preferably used are styrene resin, acrylic resin, and
polyester resin which have high coagulation energy.
[0152] Examples of (1) polyolefin resins include polyolefin resins
such as polyethylene, polypropylene and the like; copolymer resins
of olefins (such as ethylene, propylene and the like) with other
vinyl monomers; and the like. Examples of the above copolymer
resins of olefins with other vinyl monomers include ethylene-vinyl
acetate copolymer; an ionomer resin which is a copolymer of olefins
with acrylic acid or methacrylic acid; and the like. Herein,
examples of the derivatives of the polyolefin include chlorinated
polyethylene, chlorosulfonated polyethylene and the like.
[0153] Examples of (2) polystyrene resins include polystyrene
resin, styrene-isobutylene copolymer, acrylonitrile-styrene
copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer
(ABS resin), polystyrene-maleic anhydride resin and the like.
[0154] Examples of (3) acrylic resins include polyacrylic acid or
esters thereof, polymethacrylic acid or esters thereof,
polyacrylonitrile, polyacrylamide and the like.
[0155] Examples of esters of polyacrylic acid include homopolymer
or polytypic copolymer of acrylic acid. Examples of esters of
acrylic acid include methyl acrylate, ethyl acrylate, acrylic acid
n-butyl, isobutyl acrylate, dodecyl acrylate, acrylic acid n-octyl,
acrylic acid 2-ethylhexyl, acrylic acid 2-chloroethyl, phenyl
acrylate, .alpha.-chloroacrylic acid methyl and the like.
[0156] Examples of esters of polymethacrylic acid include
homopolymer or polytypic copolymer of methacrylic acid. Examples of
esters of methacrylic acid include methyl methacrylate, ethyl
methacrylate, butyl methacrylate and the like.
[0157] Examples of (4) polyvinyl acetates or derivatives thereof
include polyvinyl acetate and polyvinyl alcohol which is obtained
by saponifying polyvinyl acetate, polyvinyl acetal resin obtained
by reacting polyvinyl alcohol with aldehyde (for example,
formaldehyde, acetaldehyde, butylaldehyde and the like), and the
like.
[0158] Examples of (5) polyamide resins include polycondensation of
diamine with dibasic acid such as 6-nylon, 6,6-nylon and the
like.
[0159] (6) polyester resin is produced by polycondensation of acid
composition with alcohol composition. The acid composition is not
particularly limited, and can be suitably selected according to the
object. Examples of (6) polyester resins include maleic acid,
fumaric acid, citraconic acid, itaconic acid, glutaconic acid,
phthalic acid, terephthalic acid, isophthalic acid, succinic acid,
adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenyl
succinate, isododecenyl succinate, n-dodecyl succinate, isododecyl
succinate, n-octenyl succinate, n-octyl succinate, isooctenyl
succinate, isooctyl succinate, trimellitic acid, pyromellitic acid,
acid anhydrides thereof, low alcohol esters thereof, and the
like.
[0160] The above alcohol composition is not particularly limited,
and can be suitably selected according to the object. Diatomic
alcohol is preferable. Examples of fatty series diols include
ethylene glycol, diethylene glycol, triethylene glycol,
1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol,
neopentyl glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol,
1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol,
polypropylene glycol, polytetramethylene glycol and the like.
Examples of alkylene oxide adducts of bisphenol A include
polyoxypropylene, (2.2)-2,2-bis (4-hydroxyphenyl)propane,
polyoxypropylene (3.3)-2,2-bis (4-hydroxyphenyl)propane,
polyoxyethylene (2.0)-2,2-bis (4-hydroxyphenyl)propane,
polyoxypropylene (2.0)-polyoxyethylene
(2.0)-2,2-bis(4-hydroxyphenyl)propylene, polyoxypropylene
(6)-2,2-bis(4-hydroxyphenyl)propane and the like.
[0161] A general example of (7) polycarbonate resin is
polycarbonate ester which is obtained by bisphenol A and
phosgene.
[0162] Examples of (8) polyether resins (or acetal resin) include
polyether resins such as polyethylene oxide, polypropylene oxide
and the like; acetal resins such as polyoxymethylene as
ring-opening polymerization and the like; and the like.
[0163] Examples of (9) other resins include polyurethane resin of
polyaddition.
[0164] As the polymer for the toner image-receiving layer, those
satisfying toner image-receiving layer properties (to be described
afterward) are preferable in a state that the toner image-receiving
layer is formed. Those satisfying the above properties alone are
more preferable. Use of two or more resins with different toner
image-receiving layer properties (to be described afterward) is
also preferable.
[0165] As the polymer for the toner image-receiving layer, those
having greater molecular weight are preferable than the
thermoplastic resin used for the toner. The relative molecular
weight is, however, not limited to the above, in view of
thermodynamic properties of the thermoplastic resin used for the
toner relative to the polymer for the toner image-receiving layer.
For example, when the polymer for the toner image-receiving layer
is higher in terms of softening temperature than the thermoplastic
resin used for the toner, preferably, the molecular weight is equal
or as the case may be the polymer for the toner image-receiving
layer has smaller molecular weight.
[0166] As the polymer for the toner image-receiving layer, it is
preferable to use a mixture of resins which have the same
composition and have different average molecular weights from each
other. Japanese Patent Application Laid-Open (JP-A) No. 08-334915
discloses a preferable relation, in terms of molecular weight,
between the polymer for the toner image-receiving layer and the
thermoplastic resin used for the toner.
[0167] In terms of distribution of molecular weights, the polymer
for the toner image-receiving layer is preferably wider than the
thermoplastic resin used for the toner.
[0168] Preferably, the polymer for the toner image-receiving layer
has properties disclosed in JP-A No. 05-127413, JP-A No. 08-194394,
JP-A No. 08-334915, JP-A No. 08-334916, JP-A No. 09-171265 and JP-A
No. 10-221877.
[0169] The polymer for the toner image-receiving layer is excellent
in environmental property and workability since no organic solvent
is discharged at coating-drying step (i). Many releasing agents
such as wax are unlikely to be solved in solvent at room
temperature, and are often dispersed, prior to usage, in solvent
(water and organic solvent). Water dispersing form is more stable
and is more adaptive to production steps. Moreover, an aqueous
coating is more likely to cause bleeding of wax on the surface in
the process of coating-drying, thus making it easier to obtain the
effect of the releasing agent (antioffset property, adhesive
resistance and the like). For the above reasons, aqueous resins
such as water-dispersible polymer, water-soluble polymer and the
like are preferably used.
[0170] The above aqueous resins, provided that they are either the
water-dispersible polymer or the water-soluble polymer, are not
particularly limited in terms of composition, bonding structure,
molecular structure, molecular weight, molecular weight
distribution, form and the like, and can be suitably selected
according to the object. Examples of aqueous group of the above
polymers include sulfonic group, hydroxyl group, carboxylic group,
amino group, amide group, ether group and the like.
[0171] The above water-dispersible polymer can be made, for
example, by suitably selecting from the following and combining two
or more of them: i) resins made by dispersing in water the polymers
for toner image-receiving layer numbered by (1) to (9) above, ii)
emulsions made by dispersing in water the polymers for toner
image-receiving layer numbered by (1) to (9) above, iii) copolymer
thereof, iv) mixture thereof, and v) cationic modified product.
[0172] The water-dispersible polymer can be suitably synthesized
for use, or those commercially available are usable. Examples of
commercial products of the water-dispersible polymers include
polyester resins such as Vylonal series by Toyobo Co., Ltd.,
Pesresin A series by Takamatsu Oil & Fat Co., Ltd., Tuftone UE
series by Kao Corp., Nichigo Polyester WR series by Nippon
Synthetic Chemical Industry Co., Ltd., Elitel series by Unitika
Ltd. and the like; and acrylic resins such as Hiros XE, KE, and PE
series by Seiko Chemical Industries Co., Ltd., Jurymer ET series by
Nihon Junyaku Co., Ltd. and the like.
[0173] The water-dispersible emulsion can be any suitable emulsion
that preferably has a volume-average particle diameter of 20 nm or
more. Examples of such emulsions are water-dispersible polyurethane
emulsions, water-dispersible polyester emulsions, chloroprene
emulsions, styrene-butadiene emulsions, nitrile-butadiene
emulsions, butadiene emulsions, vinyl chloride emulsions,
vinylpyridine-styrene-butadiene emulsions, polybutene emulsions,
polyethylene emulsions, vinyl acetate emulsions, ethylene-vinyl
acetate emulsions, vinylidene chloride emulsions, and methyl
methacrylate-butadiene emulsions. Among them, water-dispersible
polyester emulsions are preferred.
[0174] The water-dispersible polyester emulsions are preferably
self-dispersible aqueous polyester emulsions, of which
self-dispersible aqueous carboxyl-containing polyester emulsions
are typically preferred. The "self-dispersible aqueous polyester
emulsion" herein means an aqueous emulsion containing a polyester
resin that is self-dispersible in an aqueous solvent without the
use of an emulsifier and the like. The "self-dispersible aqueous
carboxyl-containing polyester emulsion" means an aqueous emulsion
containing a polyester that contains carboxyl groups as hydrophilic
groups and is self-dispersible in an aqueous solvent.
[0175] The self-dispersible aqueous polyester emulsion preferably
satisfies the following requirements (1) to (4). This type of
polyester resin emulsion is self-dispersible requiring no
surfactant, is low in moisture absorbency even in an atmosphere at
high humidity, exhibits less decrease in its softening point due to
moisture and can thereby avoid offset in image-fixing and failures
due to adhesion between sheets during storage. The emulsion is
water-based and is environmentally friendly and excellent in
workability. In addition, the polyester resin used herein readily
takes a molecular structure with high coagulation energy.
Accordingly, the resin has sufficient hardness (rigidity) during
its storage but is melted with low elasticity and low viscosity
during an image-fixing process for electrophotography, and the
toner is sufficiently embedded in the toner-image-receiving layer
to thereby form images having sufficiently high quality.
(1) The number-average molecular weight Mn is preferably from 5000
to 10000 and more preferably from 5000 to 7000.
(2) The molecular weight distribution (Mw/Mn) is preferably 4 or
less, and more preferably 3 or less, wherein Mw is the
weight-average molecular weight.
(3) The glass transition temperature Tg is preferably from
40.degree. C. to 100.degree. C. and more preferably from 50.degree.
C. to 80.degree. C.
(4) The volume average particle diameter is preferably from 20 nm
to 200 nm and more preferably from 40 nm to 150 nm.
(5) The content of the water-dispersible emulsion in the
toner-image receiving layer is preferably from 10 percent to 90
percent by weight, and more preferably from 10 percent to 70
percent by weight.
[0176] The water-soluble polymer is not particularly limited,
provided that the weight average molecular weight (Mw) is 400,000
or less, and can be suitably selected according to the object. The
water-soluble polymer can be suitably synthesized for use, or
commercially available product thereof can be used. Examples of the
water-soluble polymers include polyvinyl alcohol, carboxy-modified
polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose,
cellulose sulfate, polyethylene oxide, gelatin, cationic starch,
casein, sodium polyacrylate, sodium styrene-maleic acid anhydride
copolymer: styrene-maleic acid anhydride copolymer), sodium
polystyrene sulfonate and the like. Among the above, polyethylene
oxide is preferable.
[0177] Examples of commercial products of water-soluble polymer
include various Plascoat products by Goo Chemical Co., Ltd.,
Finetex ES series by Dainippon Ink and Chemicals Inc. and the like;
and those of water-soluble acrylic resins include Jurymer AT series
by Nihon Junyaku Co., Ltd., Finetex 6161 and K-96 by Dainippon Ink
and Chemicals Inc., Hiros NL-1189 and BH-997 by Seiko Chemical
Industries Co., Ltd. and the like.
[0178] Examples of the water-soluble resins are given on page 26 of
Research Disclosure No. 17,643, page 651 of Research Disclosure No.
18,716, pp. 873-874 of Research Disclosure No. 307,105, and JP-A
No. 64-13546.
[0179] A content of the water-soluble polymer in the toner
image-receiving layer is not particularly limited, and can be
suitably selected according to the object, preferably 0.5 g/m.sup.2
to 2 g/m.sup.2.
[0180] The polymer for the toner image-receiving layer can be used
in combination with other polymer materials, in this case, however,
the polymer for the toner image-receiving layer is to be greater in
content than the other polymer materials.
[0181] In the toner image-receiving layer, the content of polymer
for the toner image-receiving layer is preferably 10% by mass or
more, more preferably 30% by mass or more, still more preferably
50% by mass or over, and particularly preferably 50% by mass to 90%
by mass.
--Releasing Agent--
[0182] The releasing agent can be blended to the toner
image-receiving layer in order to prevent offset of the toner
image-receiving layer. Various types of the releasing agent can be
used and may be suitably selected according to the object as long
as it is able to form a layer of the releasing agent on a surface
of the toner image-receiving layer by being heated and melted at a
fixing temperature so as to deposit and to remain on the surface of
the toner image-receiving layer, and by being cooled and solidified
so as to form a layer of the releasing agent, thereafter.
[0183] The releasing agent can be at least one of silicone
compounds, fluorine compounds, waxes, and matting agents.
[0184] The releasing agent may be a compound described in
Kaitei--Wakkusu no seishitsu to ouyou "Properties and Applications
of Wax (Revised)" by Saiwai Publishing, or in the Silicone Handbook
published by THE NIKKAN KOGYO SHIMBUN. Also, the silicone
compounds, fluorine compounds and wax in the toners mentioned in
Japanese Patent Application Publication (JP-B) No. 59-38581,
Japanese Patent Application Publication (JP-B) No. 04-32380,
Japanese Patent (JP-B) No. 2838498, JP-B No. 2949558, Japanese
Patent Application Laid-Open (JP-A) No. 50-117433, No. 52-52640,
No. 57-148755, No. 61-62056, No. 61-62057, No. 61-118760, and JP-A
No. 02-42451, No. 03-41465, No. 04-212175, No. 04-214570, No.
04-263267, No. 05-34966, No. 05-119514, No. 06-59502, No.
06-161150, No. 06-175396, No. 06-219040, No. 06-230600, No.
06-295093, No. 07-36210, No. 07-43940, No. 07-56387, No. 07-56390,
No. 07-64335, No. 07-199681, No. 07-223362, No. 07-287413, No.
08-184992, No. 08-227180, No. 08-248671, No. 08-248799, No.
08-248801, No. 08-278663, No. 09-152739, No. 09-160278, No.
09-185181, No. 09-319139, No. 09-319143, No. 10-20549, No.
10-48889, No. 10-198069, No. 10-207116, No. 11-2917, No. 11-44969,
No. 11-65156, No. 11-73049 and No. 11-194542 may be used. These
compounds can also be used in combination of two or more.
[0185] Examples of the silicone compounds include silicone oil,
silicone rubber, silicone fine-particle, silicone-modified resin,
reactive silicone compound and the like.
[0186] Such silicone oils include, for example, unmodified silicon
oil, amino-modified silicone oil, carboxy-modified silicone oil,
carbinol-modified silicone oil, vinyl-modified silicone oil,
epoxy-modified silicone oil, polyether-modified silicone oil,
silanol-modified silicone oil, methacrylic-modified silicone oil,
mercapto-modified silicone oil, alcohol-modified silicone oil,
alkyl-modified silicone oil, and fluorine-modified silicone
oil.
[0187] Examples of the silicone-modified resins are
silicone-modified resins derived from olefinic resins, polyester
resins, vinyl resins, polyamide resins, cellulose resins, phenoxy
resins, vinyl chloride-vinyl acetate resins, urethane resins,
acrylic resins, styrene-acrylic resins, or copolymers comprising at
least one of these constitutive monomers.
[0188] The fluorine compound is not particularly limited, and can
be suitably selected according to the object. Examples of the
fluorine compounds include fluorine oil, fluoro rubber,
fluorine-modified resin, fluorine sulfonic acid compound,
fluorosulfonic acid, fluorine acid compound or salt thereof,
inorganic fluoride and the like.
[0189] The above waxes are largely classified into two, that is,
natural wax and synthetic wax.
[0190] The natural wax is preferably at least one wax selected from
vegetable wax, animal wax, mineral wax, and petroleum wax, among
which vegetable wax is particularly preferable. The natural wax is
also preferably a water-dispersible wax, from the viewpoint of
compatibility and the like when an aqueous resin is used as the
polymer for the toner image-receiving layer.
[0191] The vegetable wax is not particularly limited, and can be
suitably selected from those known in the art. The vegetable wax
may be a commercial product, or suitably synthesized.
[0192] Examples of the vegetable waxes include carnauba wax, castor
oil, rapeseed oil, soybean oil, Japan tallow, cotton wax, rice wax,
sugarcane wax, candellila wax, Japan wax, jojoba oil, and the
like.
[0193] Examples of commercial product of the carnauba wax include
EMUSTAR AR-0413 from Nippon Seiro Co., Ltd., and Cellusol 524 from
Chukyo Yushi Co., Ltd, and the like.
[0194] Examples of commercial product of the castor oil include
purified castor oil from Itoh Oil Chemicals Co., Ltd.
[0195] Of these, carnauba wax having a melting point of 70.degree.
C. to 95.degree. C. is particularly preferable from the viewpoint
of providing an electrophotographic image-receiving paper sheet
which is excellent in antioffset properties, adhesive resistance,
paper transporting properties, gloss, is less likely to cause crack
and splitting, and is capable of forming high-quality image.
[0196] The animal wax is not particularly limited, and can be
suitably selected from those known in the art. Examples of the
animal waxes include bees wax, lanolin, spermaceti, whale oil, wool
wax and the like.
[0197] The mineral wax is not particularly limited, and can be
suitably selected from those known in the art. The mineral wax may
be commercial product, or suitably synthesized.
[0198] Examples of the mineral waxes include montan wax, montan
ester wax, ozokerite, ceresin and the like. Of these, montan wax
having a melting point of 70.degree. C. to 95.degree. C. is
particularly preferable from the viewpoint of providing an
electrophotographic image-receiving paper sheet which is excellent
in antioffset properties, adhesive resistance, paper transporting
properties, gloss, is less likely to cause crack and splitting, and
is capable of forming high-quality image.
[0199] The petroleum wax is not particularly limited, and can be
suitably selected from those known in the art. The petroleum wax
may be commercial product, or suitably synthesized.
[0200] Examples of the petroleum waxes include paraffin wax, a
microcrystalline wax, and petrolatum and the like.
[0201] A content of the natural wax in the toner image-receiving
layer (a surface) is preferably 0.1 g/m.sup.2 to 4 g/m.sup.2, and
more preferably 0.2 g/m.sup.2 to 2 g/m.sup.2.
[0202] When the content is less than 0.1 g/m.sup.2, the antioffset
properties and the adhesive resistance may deteriorate. When the
content is more than 4 g/m.sup.2, the quality of an image may
deteriorate because of the excessive amount of wax.
[0203] The melting point of the natural wax is preferably
70.degree. C. to 95.degree. C., and more preferably 75.degree. C.
to 90.degree. C., from the viewpoint of antioffset properties and
paper transporting properties.
[0204] The synthetic waxes are classified into synthetic
hydrocarbon, modified wax, hydrogenated wax, and other grease
synthetic wax. The synthetic wax is preferably a water-dispersible
wax, from the viewpoint of compatibility when an aqueous
thermoplastic resin is used as the thermoplastic resin in the toner
image-receiving layer.
[0205] Examples of the synthetic hydrocarbons include
Fischertropsch wax, polyethylene wax and the like.
[0206] Examples of the grease synthetic waxes include an acid amide
compound (specifically, stearic acid amide and the like), an acid
imide compound (specifically, anhydrous phthalic acid imide and the
like) and the like.
[0207] The modified wax is not particularly limited, and can be
suitably selected according to the object. Examples of the modified
waxes include amine-modified wax, acrylic acid-modified wax,
fluorine-modified wax, olefin-modified wax, urethane wax, alcohol
wax and the like.
[0208] The hydrogenated wax is not particularly limited, and can be
suitably selected according to the object. Examples of the
hydrogenated waxes include cured castor oil, castor oil
derivatives, stearic acid, lauric acid, myristic acid, palmitic
acid, behenic acid, sebacic acid, undecylenic acid, heptyl acids,
maleic acid, high grade maleic oils and the like.
[0209] The matting agent can be selected from any known matting
agents. Solid particles used as the matting agent can be classified
into inorganic particles and organic particles. Specifically, the
inorganic matting agents may be oxides (for example, silicon
dioxide, titanium oxide, magnesium oxide, and aluminum oxide),
alkaline earth metal salts (for example, barium sulfate, calcium
carbonate, and magnesium sulfate), silver halides (for example,
silver chloride, and silver bromide), glass and the like.
[0210] Examples of the inorganic matting agents can be found in
West German Patent No. 2529321, the U.K. Patent Nos. 760775,
1260772, and the U.S. Pat. Nos. 1,201,905, 2,192,241, 3,053,662,
3,062,649, 3,257,206, 3,322,555, 3,353,958, 3,370,951, 3,411,907,
3,437,484, 3,523,022, 3,615,554, 3,635,714, 3,769,020, 4,021,245
and 4,029,504.
[0211] Materials of the organic matting agent include starch,
cellulose ester (for example, cellulose-acetate propionate),
cellulose ether (for example, ethyl cellulose) and a synthetic
resin. It is preferred that the synthetic resin is insoluble or
difficult to become solved. Examples of synthetic resins that are
insoluble or of low solubility in water include poly(meth)acrylates
(for example, polyalkyl(meth)acrylate,
polyalkoxyalkyl(meth)acrylate, polyglycidyl(meth)acrylate),
poly(meth) acrylamide, polyvinyl ester (for example, polyvinyl
acetate), polyacrylonitrile, polyolefins (for example,
polyethylene), polystyrene, benzoguanamine resin, formaldehyde
condensation polymer, epoxy resin, polyamide, polycarbonate,
phenolic resin, polyvinyl carbazole, polyvinylidene chloride and
the like.
[0212] Copolymers, that is, a combination of monomers used in the
above polymers may also be used.
[0213] In the case of the copolymers, a small amount of hydrophilic
repeating units may be included. Examples of monomers which
constitute these hydrophilic repeating units include acrylic acid,
methacrylic acid, .alpha.,.beta.-unsaturated dicarboxylic acid,
hydroxyalkyl(meth)acrylate, sulfoalkyl(meth)acrylate, styrene
sulfonic acid and the like.
[0214] Examples of the organic matting agents can be found in the
U.K. Patent No. 1055713, the U.S. Pat. Nos. 1,939,213, 2,221,873,
2,268,662, 2,322,037, 2,376,005, 2,391,181, 2,701,245, 2,992,101,
3,079,257, 3,262,782, 3,443,946, 3,516,832, 3,539,344, 3,591,379,
3,754,924 and 3,767,448, and JP-A Nos. 49-106821, and 57-14835.
[0215] Also, two or more types of solid particles may be used in
combination. The average particle size of the solid particles may
suitably be, for example, 1 .mu.m to 100 .mu.m, and is more
preferably 4 .mu.m to 30 .mu.m. The usage amount of the solid
particles may suitably be 0.01 g/m.sup.2 to 0.5 g/m.sup.2, and is
more preferably 0.02 g/m.sup.2 to 0.3 g/m.sup.2.
[0216] The melting point (.degree. C.) of the releasing agent is
preferably 70.degree. C. to 95.degree. C., and more preferably
75.degree. C. to 90.degree. C., from the viewpoint of antioffset
properties and paper transport properties.
[0217] The release agent under the present invention which is added
to a toner image-receiving layer may also use derivatives, oxides,
refined products, or mixtures of these. These may also have
reactive substituents.
[0218] The content of the releasing agent, based on the mass of the
toner image-receiving layer, is preferably 0.1% by mass to 10% by
mass, more preferably 0.3% by mass to 8.0% by mass, and still more
preferably 0.5% by mass to 5.0% by mass.
[0219] The content less than 0.1% by mass may make the antioffset
property and adhesion resistance insufficient, while more than 10%
by mass may deteriorate the image quality due to too large an
amount of releasing agent.
--Plasticizers--
[0220] The plasticizers known in the art may be used without any
particular limitation. These plasticizers have the effect of
adjusting the fluidity or softening of the toner image-receiving
layer due to one of heat and pressure during toner fixing.
[0221] The plasticizer may be selected by referring to Kagaku
binran "Chemical Handbook" (ed. The Chemical Society of Japan,
Maruzen), Kasozai--Sono riron to ouyou "Plasticizers--Theory and
Application" (ed. Koichi Murai, Saiwai Shobo), Kasozai no
kenkyu--jou "The Study of Plasticizers, Part 1" and Kasozai no
kenkyu--ge "The Study of Plasticizers, Part 2" (ed. Polymer
Chemistry Association), or Binran--Gomu purasuchikku haigou yakuhin
"Handbook of Rubber and Plastics Blending Agents" (ed. Rubber
Digest Co.), or the like.
[0222] Examples of the plasticizers include esters (for example,
phthalic esters, phosphate esters, aliphatic acid esters, abiethyne
acid ester, abietic acid ester, sebacic acid esters, azelinic
ester, benzoates, butylates, epoxy aliphatic acid esters, glycolic
acid esters, propionic acid esters, trimellitic acid esters,
citrates, sulfonates, carboxylates, succinic acid esters, maleates,
fumaric acid esters, phthalic acid esters, stearic acid esters and
the like); amides (for example, aliphatic acid amides and
sulfoamides and the like); ethers; alcohols; lactones;
polyethyleneoxy; and the like (See JP-A Nos. 59-83154, 59-178451,
59-178453, 59-178454, 59-178455, 59-178457, 62-174754, 62-245253,
61-209444, 61-200538, 62-8145, 62-9348, 62-30247, 62-136646, and
02-235694 and the like).
[0223] The above plasticizers can be mixed into a resin for
use.
[0224] The plasticizers may be polymers having relatively low
molecular weight. In this case, it is preferred that the molecular
weight of the plasticizer is lower than the molecular weight of the
binder resin to be plasticized. Preferably, plasticizers have a
molecular weight of 15000 or less, or more preferably 5000 or less.
When a polymer plasticizer is used as the plasticizer, the kind of
the polymer of the polymer plasticizer is preferably the same as
that of the binder resin to be plasticized. For example, when the
polyester resin is plasticized, polyester having low molecular
weight is preferable. Further, oligomers may also be used as
plasticizers.
[0225] Apart from the compounds mentioned above, there are
commercial products such as, for example, Adecasizer PN-170 and
PN-1430 (from Asahi Denka Co., Ltd.); PARAPLEX-G-25, G-30 and G40
(from C. P. Hall); and, rosin ester (ester gum) 8 L-JA, ester R-95,
pentalin 4851, FK 115, 4820, 830, Ruizol 28-JA, Picolastic A75,
Picotex LC and Cristalex 3085 (from Rika Hercules, Inc) and the
like.
[0226] The plasticizer can be used as desired to relax stress and
distortion (physical distortions such as elasticity and viscosity,
and distortions of mass balance in molecules, binder main chains or
pendant portions) which are produced when toner particles are
embedded in the toner image-receiving layer.
[0227] The plasticizer may be dispersed in micro in the toner
image-receiving layer. The plasticizer may also be dispersed in
micro, in a state of sea-island, in the toner image-receiving
layer. The plasticizer may present in the toner image-receiving
layer in a state of sufficiently mixed with other components such
as binder or the like.
[0228] The content of plasticizer in the toner image-receiving
layer is preferably 0.001% by mass to 90% by mass, more preferably
0.1% by mass to 60% by mass, and still more preferably 1% by mass
to 40% by mass.
[0229] The plasticizer may be used for the purpose of adjusting
slidability (improvement of transportability by reducing friction),
improving fixing part offset (release of toner or layer to the
fixing part), adjusting curl balance, adjusting charge control
(formation of a toner electrostatic image), and the like.
--Colorant--
[0230] The colorant is not particularly limited, and can be
suitably selected according to the object. Examples of colorants
include fluorescent whitening agents, white pigments, colored
pigments, dyes and the like.
[0231] The fluorescent whitening agent has absorption in the
near-ultraviolet region, and is a compound which emits fluorescence
at 400 nm to 500 nm. Various fluorescent whitening agents known in
the art may be used without any particular limitation. Examples of
the fluorescent whitening agents include the compounds described in
The Chemistry of Synthetic Dyes Volume V, Chapter 8 edited by K.
VeenRataraman. The fluorescent whitening agent can be suitably
synthesized for use, or those commercially available are usable.
Specific examples of the fluorescent whitening agents include
stilbene compounds, coumarin compounds, biphenyl compounds,
benzo-oxazoline compounds, naphthalimide compounds, pyrazoline
compounds, carbostyryl compounds and the like. Examples of the
commercial fluorescent whitening agents include WHITEX PSN, PHR,
HCS, PCS, and B (from Sumitomo Chemicals), UVITEX-OB (from
Ciba-Geigy, Co., Ltd.), and the like.
[0232] The white pigment is not particularly limited, and can be
suitably selected from those known in the art according to the
object. Examples of the white pigments include the inorganic
pigments such as titanium oxide, calcium carbonate and the
like.
[0233] The colored pigment is not particularly limited, and can be
suitably selected from those known in the art according to the
object. Examples of the colored pigments include various pigments
described in JP-A No. 6344653, azo pigments, polycyclic pigments,
condensed polycyclic pigments, lake pigments, carbon black and the
like.
[0234] Examples of the azo pigments include azo lakes (such as
carmine 6B, red 2B and the like), insoluble azo compounds (such as
monoazo yellow, disazo yellow, pyrazolo orange, Balkan orange and
the like), condensed azo pigments (such as chromophthal yellow and
chromophthal red), and the like.
[0235] Examples of the polycyclic pigments include phthalocyanines
such as copper phthalocyanine blue, copper phthalocyanine green,
and the like.
[0236] Examples of the condensed polycyclic pigments include
dioxazines (such as dioxazine violet), isoindolinones (such as
isoindolinone yellow), threne pigments, perylene pigments, perinon
pigments, thioindigo pigments, and the like.
[0237] Examples of the lake pigments include malachite green,
rhodamine B, rhodamine G, Victoria blue B and the like.
[0238] Examples of the inorganic pigments include oxide (titanium
dioxide, iron oxide red and the like), sulfate (settling barium
sulfate and the like), carbonate (settling calcium carbonate and
the like), silicate (hydrous silicate, silicic anhydride and the
like), metal powder (aluminum powder, bronze powder, zinc powder,
chrome yellow, iron blue and the like) and the like.
[0239] The above pigments can be used either alone or in
combination of two or more.
[0240] The dye is not particularly limited, and can be suitably
selected from those known in the art according to the object.
Examples of the dyes include anthraquinone compounds, azo compounds
and the like. These can be used either alone or in combination of
two or more.
[0241] Examples of water-insoluble dyes include architecture dye,
disperse dye, oil-soluble dye and the like.
[0242] Examples of the architecture dyes include vat dyes such as
C. I. Vat violet 1, C. I. Vat violet 2, C. I. Vat violet 9, C. I.
Vat violet 13, C. I. Vat violet 21, C. I. Vat blue 1, C. I. Vat
blue 3, C. I. Vat blue 4, C. I. Vat blue 6, C. I. Vat blue 14, C.
I. Vat blue 20, C. I. Vat blue 35 and the like. Examples of the
disperse dyes include C. I. disperse violet 1, C. I. disperse
violet 4, C. I. disperse violet 10, C. I. disperse blue 3, C. I.
disperse blue 7, C. I. disperse blue 58 and the like. Examples of
the oil-soluble dyes include C. I. solvent violet 13, C. I. solvent
violet 14, C. I. solvent violet 21, C. I. solvent violet 27, C. I.
solvent blue 11, C. I. solvent blue 12, C. I. solvent blue 25, C.
I. solvent blue 55 and the like.
[0243] Colored couplers used in silver halide photography may also
be preferably used.
[0244] A content of the colorant in the toner image-receiving layer
(surface) is preferably 0.1 g/m.sup.2 to 8 g/m.sup.2, and more
preferably 0.5 g/m.sup.2 to 5 g/m.sup.2.
[0245] When the content of colorant is less than 0.1 g/m.sup.2, the
light transmittance in the toner image-receiving layer becomes
high. When it is more than 8 g/m.sup.2, handling becomes more
difficult, due to crack and adhesive resistance.
[0246] Among the colorants, the amount of the added pigment is,
based on the mass of the thermoplastic resin constituting the toner
image-receiving layer, preferably 40% by mass, more preferably 30%
by mass or less, and still more preferably 20% by mass or less.
[0247] The filler may be an organic or inorganic filler.
Reinforcers for binder resins, bulking agents and reinforcements
known in the art may be used. The filler may be selected, referring
to "Handbook of Rubber and Plastics Additives" (ed. Rubber Digest
Co.), "Plastics Blending Agents--Basics and Applications" (New
Edition) (Taisei Co.), "The Filler Handbook" (Taisei Co.), or the
like.
[0248] As the filler, various inorganic fillers or inorganic
pigments can be used suitably. Examples of inorganic fillers or
inorganic pigments include silica, alumina, titanium dioxide, zinc
oxide, zirconium oxide, micaceous iron oxide, white lead, lead
oxide, cobalt oxide, strontium chromate, molybdenum pigments,
smectite, magnesium oxide, calcium oxide, calcium carbonate,
mullite and the like. Of these, silica and alumina are particularly
preferred. These may be used either alone, or in combination of two
or more. It is preferred that the filler has a small particle
diameter. When the particle diameter is large, the surface of the
toner image-receiving layer tends to become rough.
[0249] Examples of the silicas include spherical silica and
amorphous silica. The silica may be synthesized by the dry method,
wet method or aerogel method. The surface of the hydrophobic silica
particles may also be treated by trimethylsilyl groups or silicone.
Colloidal silica is preferred. The silica is preferably porous.
[0250] The alumina includes anhydrous alumina and hydrated alumina.
Examples of crystallized anhydrous aluminas which may be used are
.alpha., .beta., .gamma., .delta., .zeta., .eta., .theta., .kappa.,
.rho., or .chi.. Hydrated alumina is preferred to anhydrous
alumina. The hydrated alumina may be a monohydrate or trihydrate.
Monohydrates include pseudo-boehmite, boehmite and diaspore.
Trihydrates include gibbsite and bayerite. Porous alumina is
preferred.
[0251] The alumina hydrate can be synthesized by the sol-gel
method, in which ammonia is added to an aluminum salt solution to
precipitate alumina, or by hydrolysis of an alkali aluminate.
Anhydrous alumina can be obtained by dehydrating alumina hydrate by
the action of heat.
[0252] The amount of filler to be added is preferably from 5 parts
by mass to 2000 parts by mass relative to 100 parts by mass of the
dry mass of the binder of the toner image-receiving layer.
[0253] A cross-linking agent can be added in order to adjust the
storage stability or thermoplastic properties of the toner
image-receiving layer. Examples of the cross-linking agents include
compounds containing two or more reactive groups in the molecule,
such as an epoxy group, an isocyanate group, an aldehyde group, an
active halogen group, an active methylene group, an acetylene group
and other reactive groups known in the art.
[0254] The cross-linking agent may also be a compound having two or
more groups capable of forming bonds such as hydrogen bonds, ionic
bonds, coordinate bonds, or the like.
[0255] Examples of the cross-linking agents include a coupling
agent for resin, curing agent, polymerizing agent, polymerization
promoter, coagulant, film-forming agent, film-forming assistant, or
the like. Examples of the coupling agents include chlorosilanes,
vinylsilanes, epoxysilanes, aminosilanes, alkoxyaluminum chelates,
titanate coupling agents and the like. The examples further include
other agents known in the art such as those mentioned in
Binran--Gomu purasuchikkusu no haigou yakuhin "Handbook of Rubber
and Plastics Additives" (ed. Rubber Digest Co.).
[0256] The charge control agent is preferably added to adjust toner
transfer, adhesion or the like to the toner image-receiving layer,
and to prevent charge adhesion of the toner image-receiving
layer.
[0257] The charge control agent may, without limitation, be any
charge control agent known in the art. Examples of the charge
control agents include surfactants such as a cationic surfactant,
an anionic surfactant, an amphoteric surfactant, a nonionic
surfactant, or the like; polymer electrolytes, conductive metal
oxides; and the like. Examples include cationic charge inhibitors
such as quaternary ammonium salts, polyamine derivatives,
cation-modified polymethylmethacrylate, cation-modified
polystyrene, or the like; anionic charge inhibitors such as alkyl
phosphates, anionic polymers, or the like; and nonionic charge
inhibitors such as aliphatic ester, polyethylene oxide, or the
like. The examples are not limited thereto, however.
[0258] When the toner has a negative charge, it is preferred that
the charge control agent blended with the toner image-receiving
layer is, for example, cationic or nonionic.
[0259] Examples of the conductive metal oxides include ZnO,
TiO.sub.2, SnO.sub.2, Al.sub.2O.sub.3, In.sub.2O.sub.3, SiO.sub.2,
MgO, BaO, MoO.sub.3 and the like. These conductive metal oxides may
be used alone, or may be used in combination of two or more.
Moreover, the conductive metal oxide may contain (dope) other
elements. For example, ZnO may contain Al, In, or the like,
TiO.sub.2 may contain Nb, Ta, or the like, and SnO.sub.2 may
contain Sb, Nb, halogen elements, or the like.
--Other Additives--
[0260] The materials used for the toner image-receiving layer may
also contain various additives to improve image stability when
output, or to improve stability of the toner image-receiving layer
itself. Examples of the additives include various known
antioxidants, age resistors, degradation inhibitors, ozone
degradation inhibitors, ultraviolet ray absorbers, metal complexes,
light stabilizers, preservatives, fungicide and the like.
[0261] The antioxidant is not particularly limited, and can be
suitably selected according to the object. Examples of the
antioxidants include chroman compounds, coumarane compounds, phenol
compounds (for example, hindered phenols), hydroquinone
derivatives, hindered amine derivatives, spiroindan compounds and
the like. The antioxidants can be found in JP-A No. 61-159644.
[0262] Examples of age resistors include those found in
Binran--Gomu purasuchikku haigou yakuhin--kaitei dai 2 han
"Handbook of Rubber and Plastics Additives, Second Edition" (1993,
Rubber Digest Co.), pp. 76-121.
[0263] The ultraviolet ray absorber is not particularly limited,
and can be suitably selected according to the object. Examples of
the ultraviolet ray absorbers include benzotriazol compounds
(described in the U.S. Pat. No. 3,533,794), 4-thiazolidone
compounds (described in the U.S. Pat. No. 3,352,681), benzophenone
compounds (described in JP-A No. 46-2784), ultraviolet ray
absorbing polymers (described in JP-A No. 62-260152).
[0264] The metal complex is not particularly limited, and can be
suitably selected according to the object. Examples of the metal
complexes include those described in U.S. Pat. Nos. 4,241,155,
4,245,018, 4,254,195, JP-A Nos. 61-88256, 62-174741, 63-199248,
01-75568, 01-74272 and the like.
[0265] The ultraviolet ray absorbers and light stabilizers found in
Binran--Gomu purasuchikku haigou yakuhin--kaitei dai 2 han
"Handbook of Rubber and Plastics Additives, Second Edition" (1993,
Rubber Digest Co.), pp. 122-137 are preferably used.
[0266] Additives for photography known in the art may also be added
to the material used for the toner image-receiving layer as
described above. Examples of the photographic additives can be
found in the Journal of Research Disclosure (hereinafter referred
to as RD) No. 17643 (December 1978), No. 18716 (November 1979) and
No. 307105 (November 1989). The relevant sections are shown.
TABLE-US-00001 TABLE 1 Type of additive RD17643 RD18716 RD307105 1.
Whitener p. 24 p. 648 right p. 868 column 2. Stabilizer pp. 24-25
p. 649 right pp. 868-870 column 3. Light absorber pp. 25-26 p. 649
right pp. 873 (Ultraviolet ray absorber) column 4. Colorant image
p. 25 p. 650 right p. 872 stabilizer column 5. Film hardener p. 26
p. 651 left column p. 874-875 6. Binder p. 26 p. 651 left column p.
873-874 7. Plasticizer, lubricant p. 27 p. 650 right p. 876 column
8. Auxiliary application pp. 26-27 p. 650 right pp. 875-876 agent
column (Surfactant) 9. Antistatic agent p. 27 p. 650 right p.
876-877 column 10. Matting agent pp. 878-879
[0267] The toner image-receiving layer under the present invention
is formed by applying with a wire coater and the like the coating
solution (containing thermoplastic resin for the toner
image-receiving layer) to the support and by drying it. The minimum
film-forming temperature (MFT) of the thermoplastic resin under the
present invention is preferably the room temperature or higher,
from the viewpoint of pre-print storage, and preferably 100.degree.
C. or lower, from the viewpoint of fixing toner particles.
[0268] The toner image-receiving layer under the present invention
preferably has the application mass after drying in a range from 1
g/cm.sup.2 to 20 g/cm.sup.2, more preferably 4 g/cm.sup.2 to 15
g/cm.sup.2.
[0269] Thickness of the toner image-receiving layer is not
particularly limited, and can be suitably selected according to the
object. For example, the thickness is preferably from 1 .mu.m to 50
.mu.m, more preferably from 1 .mu.m to 30 .mu.m, still more
preferably 2 .mu.m to 20 .mu.m, and particularly preferably 5 .mu.m
to 15 .mu.m.
--Physical Properties of Toner Image-Receiving Layer--
[0270] The 180.degree. separation strength of the toner
image-receiving layer at the temperature for fixing with the fixing
member is preferably 0.1 N/25 mm or less, and more preferably 0.041
N/25 mm or less. The 180.degree. separation strength can be
measured based on the method described in JIS K6887 using the
surface material of the fixing member.
[0271] It is preferred that the toner image-receiving layer has a
high degree of whiteness. This whiteness is measured by the method
specified in JIS P 8123, and is preferably 85% or more. It is
preferred that the spectral reflectance is 85% or more in the
wavelength range of 440 nm to 640 nm, and that the difference
between the maximum spectral reflectance and the minimum spectral
reflectance in this wavelength range is within 5%. Further, it is
more preferred that the spectral reflectance is 85% or more in the
wavelength range from 400 nm to 700 nm, and that the difference
between the maximum spectral reflectance and the minimum spectral
reflectance in the wavelength is within 5%.
[0272] Specifically, for the whiteness, the value of L* is
preferably 80 or more, more preferably 85 or more, and still more
preferably 90 or more in a CIE 1976 (L*a*b*) color space. The color
tint of the white color is preferably as neutral as possible.
Regarding the color tint of the whiteness, the value of
(a*).sup.2+(b*).sup.2 is preferably 50 or less, more preferably 18
or less, and still more preferably 5 or less in the (L*a*b*)
space.
[0273] It is preferred that the toner image-receiving layer has a
high surface gloss after being formed. The 45.degree. gloss luster
is preferably 60 or more, more preferably 75 or more, and still
more preferably 90 or more, over the whole range from white where
there is no toner, to black where toner is densed at maximum.
[0274] However, the gloss luster is preferably 110 or less. When it
is more than 110, the image has a metallic luster which is
undesirable.
[0275] Gloss luster may be measured by JIS Z 8741.
[0276] It is preferred that the toner image-receiving layer has
high smoothness after fixing. The arithmetic average roughness (Ra)
is preferably 3 .mu.m or less, more preferably 1 .mu.m or less, and
still more preferably 0.5 .mu.m or less, over the whole range from
white where there is no toner, to black where toner is densed at
maximum.
[0277] Arithmetic average roughness may be measured by JIS B 0601,
JIS B 0651, and JIS B 0652.
[0278] It is preferred that the toner image-receiving layer has one
of the following physical properties, more preferred that the toner
image-receiving layer has several of the following physical
properties, and most preferred that the toner image-receiving layer
has all of the following physical properties.
(1) T.sub.m (melting temperature of toner image-receiving layer) is
preferably 30.degree. C. or more, and more preferably equal to or
less than T.sub.m (melting temperature of toner)+20.degree. C.
(2) The temperature at which the viscosity of the toner
image-receiving layer is 1.times.10.sup.5 cp is preferably
40.degree. C. or higher, and more preferably lower than the
corresponding temperature for the toner.
(3) At a fixing temperature of the toner image-receiving layer, the
storage elasticity modulus (G') is preferably 1.times.10.sup.2 Pa
to 1.times.10.sup.5 Pa, the loss elasticity modulus (G'') is
preferably from 1.times.10.sup.2 Pa to 1.times.10.sup.5 Pa.
(4) The loss tangent (G''/G'), which is the ratio of the loss
elasticity modulus (G'') to the storage elasticity modulus (G') at
a fixing temperature of the toner image-receiving layer, is
preferably from 0.01 to 10.
(5) The storage elasticity modulus (G') at a fixing temperature of
the toner image-receiving layer is preferably from -50 to +2500,
relative to the storage elasticity modulus (G') at a fixing
temperature of the toner.
(6) The inclination angle on the toner image-receiving layer of the
molten toner is preferably 50.degree. or less, and more preferably
40.degree. or less.
[0279] The toner image-receiving layer preferably satisfies the
physical properties described in Japanese Patent No. 2788358, and
JP-A Nos. 07-248637, 08-305067 and 10-239889.
[0280] It is preferred that the surface electrical resistance of
the toner image-receiving layer is 1.times.10.sup.6
.OMEGA./cm.sup.2 to 1.times.10.sup.15 .OMEGA./cm.sup.2 (under
conditions of 25.degree. C., 65% RH).
[0281] When the surface electrical resistance is less than
1.times.10.sup.6 .OMEGA./cm.sup.2, the toner amount transferred to
the toner image-receiving layer is insufficient, and the density of
the toner image obtained may be too low. On the other hand, when
the surface electrical resistance is more than 1.times.10.sup.15
.OMEGA./cm.sup.2, more charge than necessary is produced during
transfer. Therefore, toner is transferred insufficiently, image
density is low and static electricity develops, thus causing dust
to adhere during handling of the electrophotographic
image-receiving paper sheet. Moreover in this case, misfeed,
overfeed, discharge marks, toner transfer dropout and the like may
occur during the copying.
[0282] The surface electrical resistances are measured based on JIS
K 6911. The sample is left with air-conditioning for 8 hours or
more at a temperature of 20.degree. C. and the humidity of 65% for
humidity adjustment. Measurements are made using an R8340 produced
by Advantest Ltd., under the same environmental conditions after
giving an electric current for 1 minute at an applied voltage of
100 V.
--Other Layers--
[0283] Other layers of the toner image-receiving layer may include,
for example, a surface protective layer, back layer, intermediate
layer, contact improving layer, undercoat, cushion layer, charge
control (inhibiting) layer, reflecting layer, tint adjusting layer,
preservability improving layer, anti-adhering layer, anti-curl
layer, smoothing layer and the like. These layers may have a
single-layer structure or may be formed of two or more layers.
[0284] The surface protective layer is formed on the surface of the
toner image-receiving layer for the purpose of protecting the
surface, improving preservability, improving handling property,
giving writing property, improving machine passing property, giving
antioffset property and the like of the electrophotographic
image-receiving paper sheet. The surface protective layer may have
a single-layer structure or may be formed of two or more layers. As
a binder, various kinds of thermoplastic resins, thermosetting
resins and the like may be used for the surface protective layer.
Resins of the binder and the toner image-receiving layer are
preferably of the same kind. In this case, however, the surface
protective layer and the toner image-receiving layer do not need to
be the same in terms of thermodynamic property, electrostatic
property and the like. Those properties can be optimized.
[0285] The surface protective layer can be blended with the various
additives described above that are usable for the toner
image-receiving layer. Particularly, the surface protective layer
can be blended with the releasing agent used under the present
invention, and other additives such as matting agent and the like.
Various known matting agents are named.
[0286] The top surface layer of the electrophotographic
image-receiving paper sheet (for example, the surface protective
layer when formed) is preferred to have compatibility with the
toner in terms of fixation property. Specifically, the top surface
layer preferably has a contact angle with the melted toner in a
range from 0.degree. to 40.degree..
[0287] The back layer of the electrophotographic image-receiving
paper sheet is preferably formed on an opposite side of the toner
image-receiving layer with respect to the support, for the purpose
of giving a backface output property, improving output image
quality of the backface, improving curl balance, improving machine
passing property and the like.
[0288] Color of the back layer is not particularly limited. In the
case of both-side output type image-receiving paper sheet forming
the image also on the backface, however, the color of the back
layer is also preferred to be white. Like the surface, the back
layer is preferred to have whiteness of 85% or more and spectral
reflectance of 85% or more.
[0289] Moreover, for improving both-side output property, the back
layer may have a structure same as that of the toner
image-receiving layer side. The back layer may use the various
kinds of additives as explained above. Examples of the blended
additives include matting agent, charge control agent and the like.
The back layer may have a single-layer structure or may be formed
of two or more layers.
[0290] When a mold-releasing oil is used for a fixing roller and
the like for preventing offset during the fixing, the back layer
may have oil absorbing property.
[0291] In the electrophotographic image-receiving paper sheet, the
above contact improving layer is preferred to be formed for
improving the contact of the support and the toner image-receiving
layer. The contact improving layer may be blended with various
additives described above, particularly the cross-linking agent.
Moreover, the electrophotographic image-receiving paper sheet is
preferred to have a cushion layer and the like between the contact
improving layer and the toner image-receiving layer, for improving
receptivity of the toner.
[0292] The intermediate layer may be formed, for example, between
the support and the contact improving layer, between the contact
improving layer and the cushion layer, between the cushion layer
and the toner image-receiving layer, between the toner
image-receiving layer and the preservability improving layer and
the like. In the case of the electrophotographic image-receiving
paper sheet that is formed with the support, the toner
image-receiving layer, and the intermediate layer, the intermediate
layer can be formed, for example, between the support and the toner
image-receiving layer.
<Toner>
[0293] The electrophotographic image-receiving paper sheet under
the present invention is used by allowing the toner image-receiving
layer to receive the toner during printing or copying.
[0294] The toner includes at least biding resin and colorant, when
necessary, releasing agent and the like.
--Toner's Binder Resin--
[0295] The binder resin is not particularly limited, and can be
selected, according to the object, from those ordinarily used for
the toner. Examples of the binder resin include vinyl monopolymer
of: styrenes such as styrene, parachlorostyrene, or the like; vinyl
esters such as vinyl naphthalene, vinyl chloride, vinyl bromide,
vinyl fluoride, vinyl acetate, vinyl propioniate, vinyl benzoate,
vinyl butyrate, or the like; methylene aliphatic carboxylates such
as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl
acrylate, dodecyl acrylate, n-octyl acrylate, 2-chloroethyl
acrylate, phenyl acrylate, .alpha.-methyl chloroacrylate, methyl
methacrylate, ethyl methacrylate, butyl acrylate, or the like;
vinyl nitriles such as acryloniotrile, methacrylonitrile,
acrylamide, or the like; vinyl ethers such as vinyl methyl ether,
vinyl ethyl ether, vinyl isobutyl ether, or the like; N-vinyl
compounds such as N-vinyl pyrrole, N-vinylcarbazole, N-vinyl
indole, N-vinyl pyrrolidone, or the like; and vinyl carboxylic
acids such as methacrylic acid, acrylic acid, cinnamic acid, or the
like. These vinyl monomers may be used either alone, or copolymers
thereof may be used. Further, various polyesters may be used, and
various waxes may be used in combination.
[0296] Among these resins, it is preferable to use a resin of the
same type as the resin used for the toner image receiving layer of
the present invention.
--Toner's Colorant--
[0297] The colorant is not particularly limited, and can be
selected according to the object from those used ordinarily for the
toner. Examples of the colorants include various kinds of pigments
such as carbon black, chrome yellow, Hansa yellow, Benzidine
Yellow, threne yellow, quinoline yellow, permanent orange GTR,
pyrazolone orange, Balkan orange, watch young red, permanent red,
brilliant carmine 3B, brilliant carmine 6B, dippon oil red,
pyrazolone red, lithol red, rhodamine B lake, lake red C, Rose
Bengale, aniline blue, ultramarine blue, chalco oil blue, methylene
blue chloride, phthalocyanine blue, phthalocyanine green, malachite
green oxalate and the like. Other examples include various kinds of
dyes such as acridine dyes, xanthene dyes, azo dyes, benzoquinone
dyes, azine dyes, anthraquinone dyes, thioindigo dyes, dioxazine
dyes, thiazine dyes, azomethine dyes, indigo dyes, phthalocyanine
dyes, aniline black dyes, polymethine dyes, triphenyl methane dyes,
diphenyl methane dyes, thiazine dyes, thiazole dyes, xanthene dyes
and the like.
[0298] The above colorants may be used alone or in combination of
two or more.
[0299] A content of the colorant is not particularly limited, and
can be suitably selected according to the object, preferably 2% by
mass to 8% by mass. The content of the colorant less than 2% by
mass may weaken tinting strength, while more than 8% by mass may
lose transmittance.
--Toner's Releasing Agent--
[0300] The releasing agent may be in principle any of the waxes
known in the art. Polar waxes containing nitrogen such as highly
crystalline polyethylene wax having relatively low molecular
weight, Fischertropsch wax, amide wax, urethane wax, and the like
are particularly effective.
[0301] For polyethylene wax, it is particularly effective when the
molecular weight is 1000 or less, and is more preferable when the
molecular weight is 300 to 1000.
[0302] Since the compounds containing urethane bonds tend to stay
in a solid state due to the strength of the coagulation force of
the polar groups even if the molecular weight is lower, and since
the melting point may be set higher in view of the molecular
weight, such compounds are suitable in general. The preferred
molecular weight is 300 to 1000. The raw materials may be selected
from various combinations such as a diisocyanic acid compound with
a mono-alcohol, a monoisocyanic acid with a mono-alcohol, dialcohol
with mono-isocyanic acid, tri-alcohol with a monoisocyanic acid,
and a triisocyanic acid compound with mono-alcohol. However, in
order to prevent the molecular weight from becoming too large, it
is preferable to combine a compound having multiple functional
groups with another compound having one functional group, and it is
important that the amount of functional groups be equivalent.
[0303] Examples of the monoisocyanic acid compounds include dodecyl
isocyanate, phenyl isocyanate and derivatives thereof, naphthyl
isocyanate, hexyl isocyanate, benzil isocyanate, butyl isocyanate,
allyl isocyanate, and the like.
[0304] Examples of the diisocyanic acid compounds include tolylene
diisocyanate, 4,4' diphenylmethane diisocyanate, toluene
diisocyanate, 1,3-phenylene diisocyanate, hexamethylene
diisocyanate, 4-methyl-m-phenylene diisocyanate, isophorone
diisocyanate, and the like.
[0305] Examples of the monoalcohols include methanol, ethanol,
propanol, butanol, pentanol, hexanol, heptanol, and the like.
[0306] Examples of the dialcohols include various glycols such as
ethylene glycol, diethylene glycol, triethylene glycol,
trimethylene glycol, and the like.
[0307] Examples of the trialcohols include trimethylol propane,
triethylol propane, trimethanol ethane, and the like.
[0308] Like an ordinary releasing agent, the above urethane
compounds can be mixed with resin or colorant, to be used as
mixed-pulverized type toner. When used for the toner of the
emulsion polymerization melting method, the urethane compound is to
be dispersed in water in combination with the ion surfactant or
high molecular electrolyte (such as high molecular acid or high
molecular base), and then heated to the melting point or more, then
subjected to a strong shearing caused by homogenizer or pressure
discharge type dispersing apparatus for forming fine-particles, to
thereby prepare releasing agent particle-containing dispersing
liquid (particle: 1 .mu.m or less) which can be used in combination
with the resin particle-containing dispersing liquid, the
colorant-containing dispersing liquid and the like.
--Other Components of Toner--
[0309] The toner can be blended with other components such as inner
additive, charge control agent, inorganic fine-particle, and the
like. Examples of the inner additives include metals such as
ferrite, magnetite, reduced iron, cobalt, nickel, manganese and the
like; alloy; magnetic bodies such as compounds including the above
metals; and the like.
[0310] Examples of charge control agents include those ordinarily
used such as quaternary ammonium salts, nigrosine compounds, dyes
made of complexes (such as aluminum, iron, chrome, and the like),
triphenyl methane pigments, and the like. It is preferable that the
charge control agent is unlikely to be soluble in water, from the
view point of controlling ion strength which may cause an effect on
stability during coagulation or meting, and the viewpoint of
reducing waste water pollutant.
[0311] Examples of the inorganic fine-particles include all
ordinary outer additives on the toner surface such as silica,
alumina, titania, calcium carbonate, magnesium carbonate,
tricalcium phosphate and the like. The above particles are
preferably used by dispersing with ion surfactant, high molecular
acid, and high molecular base.
[0312] Surfactants may also be used for emulsion polymerization,
seed polymerization, pigment dispersion, resin particle dispersion,
releasing agent dispersion, coagulation or stabilization thereof.
For example, it is effective to use, in combination, anionic
surfactants such as sulfuric acid ester salts, sulfonic acid salts,
phosphoric acid esters, soaps, or the like; cationic surfactants
such as amine salts, quaternary ammonium salts, or the like; or
non-ionic surfactants such as polyethylene glycols, alkylphenol
ethylene oxide adducts, polybasic alcohols, or the like. These may
generally be dispersed by a rotary shear homogenizer or a ball
mill, sand mill, dyno mill, or the like, all of which contain the
media.
[0313] When necessary, the toner may be added by an outer additive.
Examples of the outer additives include inorganic particle or
organic particle. Examples of the inorganic particles include
SiO.sub.2, TiO.sub.2, Al.sub.2O.sub.3, CuO, ZnO, SnO.sub.2,
Fe.sub.2O.sub.3, MgO, BaO, CaO, K.sub.2O, Na.sub.2O, ZrO.sub.2,
CaO.SiO.sub.2, K.sub.2O.(TiO.sub.2).sub.n, Al.sub.2O.sub.3,
2SiO.sub.2, CaCO.sub.3, MgCO.sub.3, BaSO.sub.4, MgSO.sub.4 and the
like. Examples of the organic particles include fatty acids or
derivatives thereof, powders of the above meal salts and the like,
resin particles (such as fluorine resin, polyethylene resin,
acrylic resin and the like), and the like.
[0314] Average particle diameter of the above is preferably from
0.01 .mu.m to 5 .mu.m, more preferably from 0.1 .mu.m to 2
.mu.m.
[0315] There is no particular limitation on the process of
manufacturing the toner, but it is preferably manufactured by a
process comprising the steps of (i) forming coagulation particles
in a dispersion of resin particles to manufacture a coagulation
particle dispersion, (ii) adding a fine particle dispersion to the
coagulation particle dispersion so that the fine particles adhere
to the coagulation particles, thus forming adhesion particles, and
(iii) heating the adhesion particles which melt to form toner
particles.
--Physical Properties of Toner--
[0316] The toner preferably has a volume average particle diameter
of 0.5 .mu.m to 10 .mu.m. Lower than the above range may cause a
harmful effect on toner's handling (supplying property,
cleanability, fluidity and the like), and may decrease particle
productivity. Larger than the above range may cause harmful effect
on image and resolution attributable to granulariness and
transferability.
[0317] It is preferable that the toner under the present invention
satisfies the above range of volume average particle diameter and
has a distribution index of volume average particle diameter (GSDv)
of 1.3 or less.
[0318] The ratio (GSDv/GSDn) of the distribution index of volume
average particle diameter (GSDv) to a distribution index of number
average particle diameter (GSDn) is preferably 0.95 or more.
[0319] It is preferable that the toner under the present invention
satisfies the above range of volume average particle diameter and
has an average (1.00 to 1.50) of configuration indexes given by the
following expression. Configuration
index=(.pi..times.L.sup.2)/(4.times.S) (where L denotes the maximum
length of toner particle, and S denotes projected area of toner
particle)
[0320] The toner satisfying the above conditions can bring about an
effect on image, particularly granulariness and resolution.
Moreover in this case, dropout or blur which may be caused by
transfer is unlikely to occur, and handling may be unlikely to be
influenced even when the average particle diameter becomes
small.
[0321] From the viewpoint of improving image quality and preventing
offset during the fixing step, it is preferable that the toner in
itself has storage elasticity modulus G' (measured at angle
frequency of 10 rad/sec) of 1.times.10.sup.2 Pa to 1.times.10.sup.5
Pa at 150.degree. C.
<Silver Salt Photographic Material>
[0322] The silver salt photographic material has, for example, a
configuration in which an image-recording layer which develops at
least yellow, magenta, and cyan (YMC) is disposed on an
image-recording material support under the present invention. It is
generally used in, for example, silver halide photography in which
an exposed and printed silver halide photographic sheet is soaked
in several treatment baths one after another so as to perform color
developing, bleaching and fixing, washing with water, and
drying.
<Inkjet-Recording Material>
[0323] The inkjet-recording material includes, for example, a
colorant-receiving layer disposed on an image-recording material
support under the present invention, where the colorant-receiving
layer is capable of receiving a liquid ink such as an aqueous ink
(using a pigment or dye as the colorant), an oil ink and the like;
a solid ink which is solid at room temperature and which is melted
and liquefied when used for a print; and the like.
<Heat Transfer Material>
[0324] The heat transfer material has, for example, a configuration
in which at least a heat-melting ink layer as an image-recording
layer is disposed on an image-recording material support under the
present invention. It is generally used in, for example, a method
in which a heat sensitive head heats the heat-melting ink layer so
as to melt and transfer the ink to a heat transfer sheet.
<Heat Sensitive Material>
[0325] The heat sensitive material has, for example, a
configuration in which at least a heat-coloring layer is disposed
on an image-recording material support under the present invention.
Examples thereof include, but are not limited to, heat sensitive
material and the like used in thermo-autochrome method (TA method)
in which a repetition of heating by a heat sensitive head and
fixing by ultraviolet light forms an image.
<Sublimation Transfer Material>
[0326] The sublimation transfer material has, for example, a
configuration in which at least an ink layer containing a
heat-diffusion pigment (subliming pigment) is disposed on an
image-recording material support under the present invention. It is
generally used in, for example, a sublimation transfer method in
which a heat sensitive head heats an ink layer so as to transfer
the heat-diffusion pigment to a sublimation transfer sheet.
<Printing Paper>
[0327] The image-recording material support is preferably used as
printing paper. In this case, the support is preferred to have high
mechanical strength since the ink is to be applied by means of a
printing machine.
[0328] The raw materials used as the image-receiving material
support preferably include filling material, softener, an inner
additive assistant for paper, and the like. The filling materials
ordinarily used are usable, whose examples including inorganic
filling materials such as clay, firing clay, diatom earth, talc,
kaolin, firing kaolin, delaminated kaolin, heavy calcium carbonate,
soft calcium carbonate, magnesium carbonate, barium carbonate,
titanium carbonate, zinc oxide, silicon oxide, amorphous silica,
aluminum hydroxide, calcium hydroxide, magnesium hydroxide, zinc
hydroxide and the like; organic filling materials such as
urea-formalin resin, polystyrene resin, phenol resin, minor hollow
particle, and the like; and the like. The above filling materials
may be used alone or in combination of two or more.
[0329] Examples of the inner additive assistants for paper-making
include those conventionally used such as various kinds of yield
promoters which are nonionic, cationic, and anionic; freeness
promoter; paper force promoter; inner additive sizing agent; and
the like. Specific examples include basic aluminum compounds such
as aluminum sulfate, aluminum chloride, sodium aluminate, basic
aluminum chloride, basic poly(aluminum hydroxide)s; polyvalent
metal compounds such as ferrous sulfate, ferric sulfate, and the
like; water soluble high polymers such as starch, modified starch,
polyacrylamide, urea resin, melamine resin, epoxy resin, polyamide
resin, polyamine resin, polyamine, polyethylene imine, plant gum,
polyvinyl alcohol, latex, polyethylene oxide, and the like; various
compounds such as hydrophilic cross-linking agent polymer particle
dispersion, derivatives thereof, and modified product thereof; and
the like. The above materials have several functions at the same
time as inner additive assistants for the paper-making.
[0330] Examples of materials having a remarkable function as inner
sizing agent include alkyl ketene dimer compounds, alkenyl succinic
anhydride compound, styrene-acrylic compound, higher fatty acid
compound, petroleum resin sizing agent, rosin sizing agent, and the
like.
[0331] Other examples of the inner sizing agents include those for
paper-making such as dye, fluorescent whitening agent, pH
regulator, defoaming agent, pitch control agent, slime control
agent, and the like.
[0332] The printing paper is particularly preferable for offset
printing paper. The other applications include relief printing,
gravure printing, electrophotography, and the like.
[0333] The image-receiving material under the present invention has
high-quality image and high gloss after image-forming, and causes a
small curl. Therefore, the image-receiving material under the
present invention is preferably used for electrophotographic
material, heat sensitive material, inkjet-recording material,
sublimation transfer material, silver salt photographic material,
heat transfer material, and the like.
EXAMPLES
[0334] Hereafter, the present invention will be described by means
of examples, but it will be understood that the invention is not
construed as being limited thereto.
Example A-1
Preparation of Image-Recording Material Support
[0335] Broad-leaf (hardwood) tree bleached kraft pulp (LBKP) was
beaten to a Canadian Standard Freeness (C. S. F.) of 280 ml using a
disk refiner, to thereby prepare a pulp paper material having fiber
length of 0.60 mm.
[0336] To this pulp paper material, the following additives were
added based on the pulp mass: cation starch 1.6% by mass, alkyl
ketene dimer (AKD) 0.4% by mass, anion polyacrylamide 0.3% by mass,
epoxidized fatty acid amide (EFA) 0.2% by mass, and polyamide
polyamine epichlorohydrine 0.2% by mass. An alkyl part of the above
alkyl ketene dimer originates from a fatty acid having a main
component of behenic acid. A fatty acid part of the epoxidized
fatty acid amide originates from a fatty acid having a main
component of behenic acid.
[0337] Thereafter, the pulp paper material was treated with a
manual paper-making machine to make wet paper having an absolute
dry weight of 140 g/m.sup.2 and water content of 68%.
[0338] Both sides of the wet paper thus obtained were covered with
filter paper and dehydrated using a wet press apparatus to adjust
water content to 47%.
[0339] The dehydrated wet paper was then dried with a press dry
treatment apparatus similar to the one shown in FIG. 1 (Static
Condebelt available from VALMET) to prepare raw paper with water
content of 7.0% after drying. The press dry treatment was performed
in a condition where the temperature of an upper plate which was in
contact with the raw paper on the side (surface) where an
image-recording layer was to be formed was set at 150.degree. C.,
the temperature of a lower plate which was in contact with the raw
paper on the side (backface) where no image-recording layer was to
be formed was set at 85.degree. C., pressure was set at 0.4 MPa,
and drying time was set at 1 second.
[0340] The press-dry-treated raw paper was then calendered using a
soft calender apparatus under the following conditions. The paper
was passed through so that a metal roller having a surface
temperature of 250.degree. C. was in contact with the side
(surface) of the raw paper on which an image-recording layer was to
be formed, while allowing a resin roll on the opposite side to have
a set surface temperature of 40.degree. C. The thus obtained paper
as the image-recording material support has a density of 0.96
g/cm.sup.3.
[0341] In this specification, including the claims, the terms
"calender," "calender apparatus," and "calendering apparatus," when
referring to a machine used for calendering, mean the same.
Example A-2 to Example A-4 and Comparative Example A-1 to
Comparative Example A-6
[0342] Various conditions for the paper-making process were set as
shown in Table 2. In the same manner as that in Example A-1,
image-recording material supports of Example A-2 to Example A-4 and
Comparative Example A-1 to Comparative Example A-6 were prepared.
TABLE-US-00002 TABLE 2 Density Dry Pulp (g/cm.sup.3) Example A-1
Press dry LBKP = 100 0.87 Example A-2 Press dry LBKP = 100 0.98
Example A-3 Press dry LBKP/NBKP = 75/25 0.93 Example A-4 Press dry
LBKP/NBKP = 75/25 1.05 Comparative Press dry LBKP/NBKP = 25/75 0.87
Example A-1 Comparative Cylinder dry LBKP = 100 0.86 Example A-2
Comparative Cylinder dry LBKP = 100 0.99 Example A-3 Comparative
Cylinder dry LBKP/NBKP = 75/25 0.97 Example A-4 Comparative
Cylinder dry LBKP/NBKP = 75/25 1.12 Example A-5 Comparative
Cylinder dry LBKP/NBKP = 50/50 0.97 Example A-6
[0343] Next, the thus obtained paper (image-recording material
support) from Example A-1 to Example A-4 and Comparative Example
A-1 to Comparative Example A-6 was subjected to an evaluation of
inner bonding strength and planarity. The results are shown in
Table 3.
<Evaluation of Inner Bonding Strength>
[0344] Inner bonding strength was measured based on JAPAN TAPPI No.
54.
<Evaluation of Planarity>
[0345] A surface configuration measuring apparatus SURFCOM 570A-3DF
(made by Tokyo Seimitsu) was used for measuring the average center
surface roughness (SRa) on the side (of the image-recording
material support) to be formed with the image-recording layer, at
the cutoff wavelength of 0.3 mm to 0.4 mm.
--Measuring Condition and Analysis Condition--
[0346] Scanning direction: MD direction of sample.
[0347] Measuring length: Machining paper direction (X-direction) 50
mm, and perpendicular direction (Y-direction) thereto 30 mm.
[0348] Measuring pitch: X-direction 0.1 mm, Y-direction 0.1 mm.
[0349] Scanning speed: 30 mm/sec.
[0350] Band pass filter: 0.3 mm to 0.4 mm
[Evaluation Standards]
[0351] A: Very good (SRa is 0.8 .mu.m or less).
[0352] B: Good (SRa is 0.8 .mu.m to less than 0.95 .mu.m).
[0353] C: Mediocre (SRa is 0.95 .mu.m to less than 1.1 .mu.m).
[0354] D: Poor (SRa is 1.1 .mu.m or more). TABLE-US-00003 TABLE 3
Inner bonding Smoothness strength Evaluation SRa (.mu.m) Example
A-1 218 mJ B 0.85 Example A-2 228 mJ A 0.73 Example A-3 268 mJ B
0.84 Example A-4 270 mJ A 0.75 Comparative 368 mJ C 0.97 Example
A-1 Comparative 149 mJ C 0.99 Example A-2 Comparative 151 mJ B 0.91
Example A-3 Comparative 192 mJ C 1.09 Example A-4 Comparative 198
mJ B 0.93 Example A-5 Comparative 240 mJ D 1.21 Example A-6
Example A-5 to Example A-8 and Comparative Example A-7 to
Comparative Example A-12
[0355] The paper sheets (image-recording material supports) of
Example A-1 to Example A-4 and Comparative Example A-1 to
Comparative Example A-6 were used for preparing the
electrophotographic image-receiving paper sheets, respectively, of
Example A-5 to Example A-8 and Comparative Example A-7 to
Comparative Example A-12, in the following methods.
--Titanium Dioxide Dispersion Solution--
[0356] The following components were blended and dispersed using an
NBK-2 non-bubbling kneader (available from Nippon Seiki) to prepare
a titanium dioxide dispersion solution (titanium dioxide pigment:
40% by mass). TABLE-US-00004 Titanium dioxide 40.0 g (TIPAQUE
(registered Trademark) A-220, available from Ishihara Sangyo
Kaisha, Ltd.) Polyvinyl alcohol 2.0 g (PVA102, available from
Kuraray Co., Ltd.) Ion exchange water 58.0 g
--Preparation of Coating Solution for Toner Image-Receiving
Layer--
[0357] The following components were mixed and stirred to prepare
the coating solution for toner image-receiving layer.
TABLE-US-00005 Aforementioned titanium dioxide dispersion 15.5 g
solution Carnauba wax dispersion solution 15.0 g (Cellosol 524,
available from Chukyo Yushi Co., Ltd.) Polyester resin aqueous
dispersion 100.0 g (solids 30% by mass, KZA-7049, Unitika Ltd.)
Thickener (Alcox E30, MEISEI CHEMICAL 2.0 g WORKS, LTD) Anionic
surfactant (AOT) 0.5 g Ion exchange water 80 ml
[0358] The thus obtained coating solution for toner image-receiving
layer had a viscosity of 40 mPas and a surface tension of 34
mN/m.
--Preparation of Back Layer Coating Solution--
[0359] The following components were mixed and stirred to prepare a
back layer coating solution. TABLE-US-00006 Acrylate resin aqueous
dispersion 100.0 g (solids 30% by mass, High-Loss XBH-997L,
available from Seiko Chemicals) Matting agent 5.0 g (Techpolymer
MBX-12, available from Sekisui Plastics Co., Ltd.) Releasing agent
(Hydrin D337, Chukyo Yushi Co., Ltd.) 10.0 g Thickener (CMC) 2.0 g
Anionic surfactant (AOT) 0.5 g Ion exchange water 80 ml
[0360] The thus obtained back layer coating solution had a
viscosity of 35 mPas and a surface tension of 33 mN/m.
--Coating of Back Layer and Toner Image-Receiving Layer--
[0361] To the backface (namely, the side not to be formed with the
toner image-receiving layer) of the image-recording material
support of each of Example A-1 to Example A-4 and Comparative
Example A-1 to Comparative Example A-6, the back layer coating
solution was applied with a bar coater, such that the coating
amount was 9 g/m.sup.2 in dry mass, to thereby form the back layer.
Then, to the surface of the image-recording material support, the
coating solution for toner image-receiving layer was applied with a
bar coater in the same manner as the back layer, such that the
coating amount was 12 g/m.sup.2 in dry mass, to thereby form the
toner image-receiving layer. The content of the pigment in the
toner image-receiving layer was 5% by mass, relative to the mass of
the thermoplastic resin.
[0362] After the back layer coating solution and the toner
image-receiving layer coating solution were coated, they were dried
by hot air, online. Airflow and temperature for drying were
adjusted, so that both the back layer and the toner image-receiving
layer were dried within 2 minutes after the coating. The point of
dryness was determined when the surface temperature of the coating
was equal to the wet-bulb temperature of the airflow for
drying.
[0363] After the drying, a calender treatment was performed. A
gloss calender was used for the calender treatment in which the
temperature of a metal roller was maintained at 40.degree. C. and a
nip pressure was set at 14.7 kN/m.sup.2 (15 kgf/cm.sup.2).
[0364] Each of the thus obtained electrophotographic
image-receiving paper sheets was cut to A4 size, and an image was
printed thereon. The printer used here was a color laser printer
(DocuColor 1250-PF) produced by Fuji Xerox Co., Ltd., excluding
that a fixing belt apparatus 1 shown in FIG. 6 was installed.
[0365] Specifically, in the fixing belt apparatus 1 as shown in
FIG. 6, a fixing belt 2 is suspended around a heating roller 3 and
a tension roller 5. A cleaning roller 6 is provided via the fixing
belt 2 above the tension roller 5, and a pressurizing roller 4 is
further provided via the fixing belt 2 below the heating roller 3.
In FIG. 6, starting from the right-hand side, the
electrophotographic image-receiving paper sheet carrying a toner
latent image was introduced between the heating roller 3 and the
pressurizing roller 4, was fixed and then transported on the fixing
belt 2. Thereafter, in this process, the electrophotographic
image-receiving paper sheet was cooled by a cooling device 7, and
the fixing belt 2 was finally cleaned by a cleaning roller 6.
[0366] In the fixing belt apparatus 1, the transport speed at the
fixing belt 2 is 30 mm/sec, the nip pressure between the heating
roller 3 and the pressurizing roller 4 was 0.2 MPa (2
kgf/cm.sup.2), and the temperature of the heating roller 3 was
150.degree. C. which corresponded to the fixing temperature. The
temperature of the pressurizing roller 4 was set at 120.degree.
C.
[0367] For each electrophotographic print thus obtained, image
quality, gloss and curl were evaluated in the following manner. The
results are shown in Table 4.
<Evaluation of Image Quality>
[0368] The image quality of each electrophotographic print was
visually observed and was evaluated. The print with the best image
quality was assigned A, followed by B, C, D and E on the following
basis.
[Evaluation Standards]
[0369] A: Very good (Effective for high image quality recording
material).
[0370] B: Good (Effective for high image quality recording
material).
[0371] C: Mediocre (Ineffective for high image quality recording
material).
[0372] D: Poor (Ineffective for high image quality recording
material).
[0373] E: Very poor (Ineffective for high image quality recording
material).
<Evaluation of Gloss>
[0374] The gloss of each electrophotographic print was visually
observed and was evaluated. The print with the best gloss was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0375] A: Very good (Effective for high image quality recording
material).
[0376] B: Good (Effective for high image quality recording
material).
[0377] C: Mediocre (Ineffective for high image quality recording
material).
[0378] D: Poor (Ineffective for high image quality recording
material).
[0379] E: Very poor (Ineffective for high image quality recording
material).
<Evaluation of Curl>
[0380] The curl of each electrophotographic print was visually
observed and was evaluated. The print with the least curl was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0381] A: No curl is found (Effective for high image quality
recording material).
[0382] B: A small curl is found, but not problematical (Effective
for high image quality recording material).
[0383] C: Curl is found (Ineffective for high image quality
recording material).
[0384] D: A large curl is found (Ineffective for high image quality
recording material). TABLE-US-00007 TABLE 4 Image Curl Support
Gloss quality property Example A-5 Example A-1 A A A Example A-6
Example A-2 A A A Example A-7 Example A-3 A A A Example A-8 Example
A-4 A A B Comparative Comparative B C A Example A-7 Example A-1
Comparative Comparative C C B Example A-8 Example A-2 Comparative
Comparative C B C Example A-9 Example A-3 Comparative Comparative C
C B Example Example A-4 A-10 Comparative Comparative C B C Example
Example A-5 A-11 Comparative Comparative C D A Example Example A-6
A-12
Example A-9 to Example A-12 and Comparative Example A-13 to
Comparative Example A-18
Preparation of Photographic Printing Paper
[0385] With the image-recording material supports prepared in
Example A-1 to Example A-4 and Comparative Example A-1 to
Comparative Example A-6, gelatin 0.1 g/m.sup.2 was applied to the
side (surface) to be formed with the image-recording layer. The
thus obtained gelatin coat face was further coated with the
overlapping coatings in the following order of: i) silver halide
gelatin emulsion layer (10 g/m.sup.2) for yellow coloring
photograph, ii) gelatin intermediate layer, iii) silver halide
gelatin emulsion layer (10 g/m.sup.2) for magenta coloring
photograph, iv) gelatin intermediate layer, v) silver halide
gelatin emulsion layer (10 g/m.sup.2) for cyanogen coloring
photograph, and vi) gelatin protective layer, to thereby prepare
the photographic printing paper sheets, respectively, of Example
A-9 to Example A-12 and Comparative Example A-13 to Comparative
Example A-18.
[0386] The photographic printing papers thus obtained were exposed
and developed to prepare photographic prints. For each photographic
print, surface smoothness (small-scale irregularity (1 mm or less)
and large-scale irregularity (5 mm to 6 mm)) was evaluated in the
following manner. The results are shown in Table 5.
<Surface Smoothness (Small-Scale Irregularity (1 mm or
Less))>
[0387] The surface appearance of each photographic print was
visually observed and was evaluated. The print with the best
surface smoothness (small-scale irregularity (1 mm or less)) was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0388] A: Very good (Effective for high image quality recording
material).
[0389] B: Good (Effective for high image quality recording
material).
[0390] C: Mediocre (Ineffective for high image quality recording
material).
[0391] D: Poor (Ineffective for high image quality recording
material).
[0392] E: Very poor (Ineffective for high image quality recording
material).
<Surface Smoothness (Large-Scale Irregularity (5 mm to 6
mm))>
[0393] The surface appearance of each photographic print was
visually observed and was evaluated. The print with the best
surface smoothness (large-scale irregularity (5 mm to 6 mm)) was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0394] A: Very good (Effective for high image quality recording
material).
[0395] B: Good (Effective for high image quality recording
material).
[0396] C: Mediocre (Ineffective for high image quality recording
material).
[0397] D: Poor (Ineffective for high image quality recording
material).
[0398] E: Very poor (Ineffective for high image quality recording
material). TABLE-US-00008 TABLE 5 Surface smoothness Small-scale
Large-scale irregularity irregularity Support (1 mm or less) (5 mm
to 6 mm) Example A-9 Example A-1 A A Example Example A-2 A A A-10
Example Example A-3 A A A-11 Example Example A-4 A A A-12
Comparative Comparative A C Example Example A-1 A-13 Comparative
Comparative D D Example Example A-2 A-14 Comparative Comparative C
B Example Example A-3 A-15 Comparative Comparative C C Example
Example A-4 A-16 Comparative Comparative C B Example Example A-5
A-17 Comparative Comparative C D Example Example A-6 A-18
Example B-1
Preparation of Image-Recording Material Support
[0399] Broad-leaf (hardwood) tree bleached kraft pulp (LBKP) was
beaten to a Canadian Standard Freeness (C. S. F.) of 300 ml using a
disk refiner, to thereby prepare a pulp paper material having fiber
length of 0.60 mm.
[0400] To this pulp paper material, the following additives were
added based on the pulp mass: cation starch 1.2% by mass, alkyl
ketene dimer (AKD) 0.5% by mass, anion polyacrylamide 0.2% by mass,
epoxidized fatty acid amide (EFA) 0.2% by mass, and polyamide
polyamine epichlorohydrine 0.3% by mass. An alkyl part of the above
alkyl ketene dimer originates from a fatty acid having a main
component of behenic acid. A fatty acid part of the epoxidized
fatty acid amide originates from a fatty acid having a main
component of behenic acid.
[0401] Thereafter, the pulp paper material was treated with a
manual paper-making machine to make wet paper having an absolute
dry weight of 160 g/m.sup.2 and water content of 68%.
[0402] Both sides of the wet paper were covered with filter paper
and dehydrated using a wet press apparatus to adjust water content
to 54%.
[0403] The dehydrated wet paper was then dried with a press dry
treatment apparatus similar to the one shown in FIG. 1 (Static
Condebelt available from VALMET) to prepare raw paper with water
content of 7.0% after drying. The press dry treatment was performed
in a condition where the temperature of an upper plate which was in
contact with the raw paper on the side (surface) where an
image-recording layer was to be formed was set at 150.degree. C.,
the temperature of a lower plate which was in contact with the raw
paper on the side (backface) where no image-recording layer was to
be formed was set at 85.degree. C., pressure was set at 0.4 MPa,
and drying time was set at 1 second.
[0404] The press-dry-treated raw paper was then calendered using a
soft calender apparatus under the following conditions. The paper
was passed through so that a metal roller having a surface
temperature of 250.degree. C. was in contact with the side
(surface) of the raw paper on which an image-recording layer was to
be formed, while allowing a resin roll on the opposite side to have
a set surface temperature of 40.degree. C.
[0405] With the image-recording material support, the Oken type
smoothness S (second) based on JAPAN TAPPI No. 5 method B was
measured on the side (surface) to be formed with the
image-recording layer. The Oken type smoothness S (second) was 251
seconds while a density .rho. (g/cm.sup.3) of the image-recording
material support was 0.95 g/cm.sup.3. From the above Oken type
smoothness S (second) and density .rho. (g/cm.sup.3), the H index
(obtained by the expression S.sup.1/2/.rho..sup.3) was measured to
be 18.4. The results are shown in Table 6.
Example B-2 to Example B-4 and Comparative Example B-1 to
Comparative Example B-5
[0406] Various conditions for the paper-making process were set as
shown in Table 6. In the same manner as that in Example B-1,
image-recording material supports of Example B-2 to Example B-4 and
Comparative Example B-1 to Comparative Example B-5 were prepared.
TABLE-US-00009 TABLE 6 .rho. Calen- (g/ H Dry der cm.sup.3)
.rho..sup.3 S S.sup.1/2 index Example B-1 Press Calen- 0.95 0.86
251 15.8 18.4 dry dered Example B-2 Press Not calen- 0.87 0.66 151
12.3 18.7 dry dered Example B-3 Press Calen- 0.98 0.94 295 17.2
18.3 dry dered Example B-4 Press Calen- 1.01 1.03 315 17.7 17.2 dry
dered Comparative Cylinder Calen- 0.81 0.53 50 7.07 13.3 Example
B-1 dry dered Comparative Cylinder Calen- 0.89 0.70 111 10.5 14.9
Example B-2 dry dered Comparative Cylinder Calen- 1.05 1.16 180
13.4 11.6 Example B-3 dry dered Comparative Cylinder Calen- 1.12
1.40 250 15.8 11.2 Example B-4 dry dered Comparative Cylinder Not
calen- 0.72 0.37 17 4.12 11.0 Example B-5 dry dered
[0407] Next, the thus obtained paper (image-recording material
support) from Example B-1 to Example B-4 and Comparative Example
B-1 to Comparative Example B-5 was subjected to an evaluation of
gloss, surface planarity, and rigidity (stiffness). The results are
shown in Table 7.
<Evaluation of Gloss>
[0408] The gloss of each image-recording material support was
visually observed and was evaluated. The support with the best
gloss was assigned A, followed by B, C, D and E on the following
basis. The results are shown in Table 7.
[Evaluation Standards]
[0409] A: Very good.
[0410] B: Good.
[0411] C: Mediocre.
[0412] D: Poor.
[0413] E: Very poor.
<Evaluation of Surface Roughness>
[0414] A surface configuration measuring apparatus SURFCOM 570A-3DF
(made by Tokyo Seimitsu) was used for measuring the average center
surface roughness (SRa) on the side (of the image-recording
material support) to be formed with the image-recording layer, at
the cutoff wavelength of 5 mm to 6 mm.
--Measuring Condition and Analysis Condition--
[0415] Scanning direction: MD direction of sample.
[0416] Measuring length: Machining paper direction (X-direction) 50
mm, and perpendicular direction (Y-direction) thereto 30 mm.
[0417] Measuring pitch: X-direction 0.1 mm, Y-direction 0.1 mm.
[0418] Scanning speed: 30 mm/sec.
[0419] Band pass filter: 5 mm to 6 mm
[Evaluation Standards]
[0420] A: Very good (SRa is 0.3 .mu.m or less).
[0421] B: Good (SRa is less than 0.5 .mu.m).
[0422] C: Mediocre (SRa is 0.5 .mu.m to less than 1.0 .mu.m).
[0423] D: Poor (SRa is 1.0 .mu.m to less than 2.0 .mu.m).
[0424] E: Very poor (SRa is 2.0 .mu.m or more).
<Evaluation of Rigidity (Stiffness)>
[0425] The rigidity (stiffness) of the image-recording material
support thus obtained was evaluated by hand-touch based on standard
1 to standard 5, where the greater the figure is the better the
rigidity (stiffness) is. The results are shown in Table 7.
TABLE-US-00010 TABLE 7 Surface Rigidity roughness Gloss (stiffness)
Example B-1 A A 4 Example B-2 A B 4 Example B-3 A A 4 Example B-4 A
A 3 Comparative D D 4 Example B-1 Comparative D C 3 Example B-2
Comparative B B 2 Example B-3 Comparative A A 1 Example B-4
Comparative E D 4 Example B-5
Example B-5 to Example B-8 and Comparative Example B-6 to
Comparative Example B-10)
[0426] The paper sheets (image-recording material supports) of
Example B-1 to Example B-4 and Comparative Example B-1 to
Comparative Example B-5 were used for preparing the
electrophotographic image-receiving paper sheets, respectively, of
Example B-5 to Example B-8 and Comparative Example B-6 to
Comparative Example B-10, in the following methods.
--Titanium Dioxide Dispersion Solution--
[0427] The following components were blended and dispersed using an
NBK-2 non-bubbling kneader (available from Nippon Seiki) to prepare
a titanium dioxide dispersion solution (titanium dioxide pigment:
40% by mass). TABLE-US-00011 Titanium dioxide 40.0 g (TIPAQUE
(registered Trademark) A-220, available from Ishihara Sangyo
Kaisha, Ltd.) Polyvinyl alcohol 2.0 g (PVA102, available from
Kuraray Co., Ltd.) Ion exchange water 58.0 g
--Preparation of Coating Solution for Toner Image-Receiving
Layer--
[0428] The following components were mixed and stirred to prepare
the coating solution for toner image-receiving layer.
TABLE-US-00012 Aforementioned titanium dioxide dispersion 15.5 g
solution Carnauba wax dispersion solution 15.0 g (Cellosol 524,
available from Chukyo Yushi Co., Ltd.) Polyester resin aqueous
dispersion 100.0 g (solids 30% by mass, KZA-7049, Unitika Ltd.)
Thickener (Alcox E30, MEISEI CHEMICAL 2.0 g WORKS, LTD) Anionic
surfactant (AOT) 0.5 g Ion exchange water 80 ml
[0429] The thus obtained coating solution for toner image-receiving
layer had a viscosity of 40 mPas and a surface tension of 34
mN/m.
--Preparation of Back Layer Coating Solution--
[0430] The following components were mixed and stirred to prepare a
back layer coating solution. TABLE-US-00013 Acrylate resin aqueous
dispersion 100.0 g (solids 30% by mass, High-Loss XBH-997L,
available from Seiko Chemicals) Matting agent 5.0 g (Techpolymer
MBX-12, available from Sekisui Plastics Co., Ltd.) Releasing agent
(Hydrin D337, Chukyo Yushi Co., Ltd.) 10.0 g Thickener (CMC) 2.0 g
Anionic surfactant (AOT) 0.5 g Ion exchange water 80 ml
[0431] The thus obtained back layer coating solution had a
viscosity of 35 mPas and a surface tension of 33 mN/m.
--Coating of Back Layer and Toner Image-Receiving Layer--
[0432] To the backface (namely, the side not to be formed with the
toner image-receiving layer) of the image-recording material
support of each of Example B-1 to Example B-4 and Comparative
Example B-1 to Comparative Example B-5, the back layer coating
solution was applied with a bar coater, such that the coating
amount was 9 g/m.sup.2 in dry mass, to thereby form the back layer.
Then, to the surface of the image-recording material support, the
coating solution for toner image-receiving layer was applied with a
bar coater in the same manner as the back layer, such that the
coating amount was 12 g/m.sup.2 in dry mass, to thereby form the
toner image-receiving layer. The content of the pigment in the
toner image-receiving layer was 5% by mass, relative to the mass of
the thermoplastic resin.
[0433] After the back layer coating solution and the toner
image-receiving layer coating solution were coated, they were dried
by hot air, online. Airflow and temperature for drying were
adjusted, so that both the back layer and the toner image-receiving
layer were dried within 2 minutes after the coating. The point of
dryness was determined when the surface temperature of the coating
was equal to the wet-bulb temperature of the airflow for
drying.
[0434] After the drying, a calender treatment was performed. A
gloss calender was used for the calender treatment in which the
temperature of a metal roller was maintained at 40.degree. C. and a
nip pressure was set at 14.7 kN/m.sup.2 (15 kgf/cm.sup.2).
[0435] Each of the thus obtained electrophotographic
image-receiving paper sheets was cut to A4 size, and an image was
printed thereon. The printer used here was a color laser printer
(DocuColor 1250-PF) produced by Fuji Xerox Co., Ltd., excluding
that a fixing belt apparatus 1 shown in FIG. 6 was installed.
[0436] Specifically, in the fixing belt apparatus 1 as shown in
FIG. 6, a fixing belt 2 is suspended around a heating roller 3 and
a tension roller 5. A cleaning roller 6 is provided via the fixing
belt 2 above the tension roller 5, and a pressurizing roller 4 is
further provided via the fixing belt 2 below the heating roller 3.
In FIG. 6, starting from the right-hand side, the
electrophotographic image-receiving paper sheet carrying a toner
latent image was introduced between the heating roller 3 and the
pressurizing roller 4, was fixed and then transported on the fixing
belt 2. Thereafter, in this process, the electrophotographic
image-receiving paper sheet was cooled by a cooling device 7, and
the fixing belt 2 was finally cleaned by a cleaning roller 6.
[0437] In the fixing belt apparatus 1, the transport speed at the
fixing belt 2 is 30 mm/sec, the nip pressure between the heating
roller 3 and the pressurizing roller 4 was 0.2 MPa (2
kgf/cm.sup.2), and the temperature of the heating roller 3 was
150.degree. C. which corresponded to the fixing temperature. The
temperature of the pressurizing roller 4 was set at 120.degree.
C.
[0438] For each electrophotographic print thus obtained, image
quality, gloss and rigidity (stiffness) were evaluated in the
following manner. The results are shown in Table 8.
<Evaluation of Image Quality>
[0439] The image quality of each electrophotographic print was
visually observed and was evaluated. The print with the best image
quality was assigned A, followed by B, C, D and E on the following
basis.
[Evaluation Standards]
[0440] A: Very good (Effective for high image quality recording
material).
[0441] B: Good (Effective for high image quality recording
material).
[0442] C: Mediocre (Ineffective for high image quality recording
material).
[0443] D: Poor (Ineffective for high image quality recording
material).
[0444] E: Very poor (Ineffective for high image quality recording
material).
<Evaluation of Gloss>
[0445] The gloss of each electrophotographic print was visually
observed and was evaluated. The print with the best gloss was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0446] A: Very good (Effective for high image quality recording
material).
[0447] B: Good (Effective for high image quality recording
material).
[0448] C: Mediocre (Ineffective for high image quality recording
material).
[0449] D: Poor (Ineffective for high image quality recording
material).
[0450] E: Very poor (Ineffective for high image quality recording
material).
<Evaluation of Rigidity (Stiffness)>
[0451] The rigidity (stiffness) of each electrophotographic print
thus obtained was evaluated by hand-touch based on standard 1 to
standard 5, where the greater the figure is the better the rigidity
(stiffness) is. TABLE-US-00014 TABLE 8 Image Rigidity Support Gloss
quality (stiffness) Example B-5 Example B-1 A A 4 Example B-6
Example B-2 A B 4 Example B-7 Example B-3 A A 4 Example B-8 Example
B-4 A A 4 Comparative Comparative D D 4 Example B-6 Example B-1
Comparative Comparative C D 4 Example B-7 Example B-2 Comparative
Comparative C B 2 Example B-8 Example B-3 Comparative Comparative B
A 2 Example B-9 Example B-4 Comparative Comparative D E 4 Example
Example B-5 B-10
Example B-9 to Example B-12 and Comparative Example B-11 to
Comparative Example B-15
Preparation of Photographic Printing Paper
[0452] With the image-recording material supports prepared in
Example B-1 to Example B-4 and Comparative Example B-1 to
Comparative Example B-5, gelatin 0.1 g/m.sup.2 was applied to the
side (surface) to be formed with the image-recording layer. The
thus obtained gelatin coat face was further coated with the
overlapping coatings in the following order of: i) silver halide
gelatin emulsion layer (10 g/m.sup.2) for yellow coloring
photograph, ii) gelatin intermediate layer, iii) silver halide
gelatin emulsion layer (10 g/m.sup.2) for magenta coloring
photograph, iv) gelatin intermediate layer, v) silver halide
gelatin emulsion layer (10 g/m.sup.2) for cyanogen coloring
photograph, and vi) gelatin protective layer, to thereby prepare
the photographic printing paper sheets, respectively, of Example
B-9 to Example B-12 and Comparative Example B-11 to Comparative
Example B-15.
[0453] The photographic printing papers thus obtained were exposed
and developed to prepare photographic prints. For each photographic
print, surface smoothness (small-scale irregularity (1 mm or less)
and large-scale irregularity (5 mm to 6 mm)) was evaluated in the
following manner. The results are shown in Table 9.
<Surface Smoothness (Small-Scale Irregularity (1 mm or
Less))>
[0454] The surface appearance of each photographic print was
visually observed and was evaluated. The print with the best
surface smoothness (small-scale irregularity (1 mm or less)) was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0455] A: Very good (Effective for high image quality recording
material).
[0456] B: Good (Effective for high image quality recording
material).
[0457] C: Mediocre (Ineffective for high image quality recording
material).
[0458] D: Poor (Ineffective for high image quality recording
material).
[0459] E: Very poor (Ineffective for high image quality recording
material).
<Surface Smoothness (Large-Scale Irregularity (5 mm to 6
mm))>
[0460] The surface appearance of each photographic print was
visually observed and was evaluated. The print with the best
surface smoothness (large-scale irregularity (5 mm to 6 mm)) was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0461] A: Very good (Effective for high image quality recording
material).
[0462] B: Good (Effective for high image quality recording
material).
[0463] C: Mediocre (Ineffective for high image quality recording
material).
[0464] D: Poor (Ineffective for high image quality recording
material).
[0465] E: Very poor (Ineffective for high image quality recording
material). TABLE-US-00015 TABLE 9 Surface smoothness Small-scale
Large-scale irregularity irregularity Support (1 mm or less) (5 mm
to 6 mm) Example B-9 Example B-1 A A Example Example B-2 A A B-10
Example Example B-3 A A B-11 Example Example B-4 A A B-12
Comparative Comparative D D Example Example B-1 B-11 Comparative
Comparative C C Example Example B-2 B-12 Comparative Comparative C
C Example Example B-3 B-13 Comparative Comparative C B Example
Example B-4 B-14 Comparative Comparative D E Example Example B-5
B-15
--Preparation of Image-Recording Material Support--
[0466] Broad-leaf (hardwood) tree bleached kraft pulp (LBKP) was
beatens to a Canadian Standard Freeness (C. S. F.) of 300 ml using
a disk refiner, to thereby prepare a pulp paper material having
fiber length of 0.58 mm.
[0467] To this pulp paper material, the following additives were
added based on the pulp mass: cation starch 1.2% by mass, alkyl
ketene dimer (AKD) 0.5% by mass, anion polyacrylamide 0.3% by mass,
epoxidized fatty acid amide (EFA) 0.2% by mass, and polyamide
polyamine epichlorohydrine 0.3% by mass. An alkyl part of the above
alkyl ketene dimer originates from a fatty acid having a main
component of behenic acid. A fatty acid part of the epoxidized
fatty acid amide originates from a fatty acid having a main
component of behenic acid.
[0468] Thereafter, the pulp paper material was treated with a
manual paper-making machine to make wet paper having an absolute
dry weight of 160 g/m.sup.2 and water content of 68%.
[0469] Both sides of the wet paper thus obtained were covered with
filter paper and dehydrated using a wet press apparatus to adjust
water content to 50%.
[0470] The dehydrated wet paper was then dried with a press dry
treatment apparatus similar to the one shown in FIG. 1 (Static
Condebelt available from VALMET) to prepare raw paper with water
content of 7.1% after drying. The press dry treatment was performed
in a condition where the temperature of an upper plate which was in
contact with the raw paper on the side (surface) where an
image-recording layer was to be formed was set at 160.degree. C.,
the temperature of a lower plate which was in contact with the raw
paper on the side (backface) where no image-recording layer was to
be formed at 85.degree. C., pressure was set at 0.45 MPa, and
drying time was set at 1 second.
[0471] The press-dry-treated raw paper was then calendered using a
machine calender apparatus under the following conditions. The
paper was passed through so that a metal roller having a surface
temperature of 110.degree. C. was in contact with the side
(surface) of the raw paper on which an image-recording layer was to
be formed. The thus obtained raw paper has a density of 1.03
g/cm.sup.3.
--Cast Coating Solution A--
[0472] A cast coating solution A having solid density of 25% by
mass was prepared which solution including 100 mass part of an
amorphous silica (Fine seal X-37 made by Tokuyama) as a pigment,
and 20 mass part of a polyvinyl alcohol (PVA105 made by KURARAY
CO., LTD.) as a binder.
--Cast Coating Solution B--
[0473] A cast coating solution B having solid density of 25% by
mass was prepared which solution including 100 mass part of an
amorphous silica (Fine seal X-37 made by Tokuyama) as a pigment,
and 10 mass part of a polyvinyl alcohol (PVA105 made by KURARAY
CO., LTD.) as a binder.
--Cast Coating Solution C--
[0474] A cast coating solution C having solid density of 25% by
mass was prepared which solution including 100 mass part of an
amorphous silica (Fine seal X-37 made by Tokuyama) as a pigment,
and 65 mass part of a polyvinyl alcohol (PVA105 made by KURARAY
CO., LTD.) as a binder.
Example C-1
Preparation of Image-Recording Material Support
[0475] A blade coater was used for coating a first face of a raw
paper sheet with a cast coating solution A such that a dried amount
of the cast coast coating solution A becomes 15 g/m.sup.2. Then, a
coagulant (borax/water/surfactant (made by Dainippon Ink and
Chemicals Inc.)=97.8/2/0.2) was applied for performing coagulation
such that its solid mass becomes 0.5 g/m.sup.2. Then, while being
in a wet state, the thus obtained coat surface is pressed to a cast
drum having a surface temperature of 100.degree. C., to thereby
produce an image-recording material support of Example C-1.
Example C-2
Preparation of Image-Recording Material Support
[0476] Example C-1 was repeated, except that the cast coating
solution A was replaced with a cast coating solution B, to thereby
produce an image-recording material support of Example C-2.
Example C-3
Preparation of Image-Recording Material Support
[0477] Example C-1 was repeated, except that the cast coating
solution A was replaced with a cast coating solution C, to thereby
produce an image-recording material support of Example C-3.
Comparative Example C-1
Preparation of Image-Recording Material Support
[0478] Example C-1 was repeated, except that the cast coat
treatment using the cast coating solution A was not performed, to
thereby produce an image-recording material support of Comparative
Example C-1.
Comparative Example C-2
Preparation of Image-Recording Material Support
[0479] Example C-1 was repeated, except that the raw paper used was
not subjected to the press dry treatment, to thereby produce an
image-recording material support of Comparative Example C-2.
[0480] Then, the supports of Example C-1 to Example C-3 and
Comparative Example C-1 to Comparative Example C-2 were evaluated
in terms of gloss and surface roughness. The results are shown in
Table 10.
<Evaluation of Gloss>
[0481] The gloss of each support was visually observed and was
evaluated. The support with the best gloss was assigned A, followed
by B, C, D and E on the following basis.
[Evaluation Standards]
[0482] A: Very good.
[0483] B: Good.
[0484] C: Mediocre.
[0485] D: Poor.
[0486] E: Very poor.
<Evaluation of Surface Smoothness>
[0487] A surface configuration measuring apparatus SURFCOM 570A-3DF
(made by Tokyo Seimitsu) was used for measuring the average center
surface roughness (SRa) on the side (of the image-recording
material support) to be formed with the image-recording layer, at
the cutoff wavelength of 5 mm to 6 mm.
--Measuring Condition and Analysis Condition--
[0488] Scanning direction: MD direction of sample.
[0489] Measuring length: Machining paper direction (X-direction) 50
mm, and perpendicular direction (Y-direction) thereto 30 mm.
[0490] Measuring pitch: X-direction 0.1 mm, Y-direction 0.1 mm.
[0491] Scanning speed: 30 mm/sec.
[0492] Band pass filter: 5 mm to 6 mm
[Evaluation Standards]
[0493] A: Very good (SRa is 0.3 .mu.m or less).
[0494] B: Good (SRa is less than 0.5 .mu.m).
[0495] C: Mediocre (SRa is 0.5 .mu.m to less than 1.0 .mu.m).
[0496] D: Poor (SRa is 1.0 .mu.m to less than 2.0 .mu.m).
[0497] E: Very poor (SRa is 2.0 .mu.m or more). TABLE-US-00016
TABLE 10 Surface Gloss smoothness Example C-1 A A Example C-2 A B
Example C-3 B A Comparative D D Example C-1 Comparative C D Example
C-2
Example C-4 to Example C-6 and Comparative Example C-3 to
Comparative Example C-4
[0498] The paper sheets (image-recording material supports) of
Example C-1 to Example C-3 and Comparative Example C-1 to
Comparative Example C-2 were used for preparing the
electrophotographic image-receiving paper sheets, respectively, of
Example C-4 to Example C-6 and Comparative Example C-3 to
Comparative Example C-4, in the following methods.
--Titanium Dioxide Dispersion Solution--
[0499] The following components were blended and dispersed using an
NBK-2 non-bubbling kneader (available from Nippon Seiki) to prepare
a titanium dioxide dispersion solution (titanium dioxide pigment:
40% by mass). TABLE-US-00017 Titanium dioxide 40.0 g (TIPAQUE
(registered Trademark) A-220, available from Ishihara Sangyo
Kaisha, Ltd.) Polyvinyl alcohol 2.0 g (PVA102, available from
Kuraray Co., Ltd.) Ion exchange water 58.0 g
--Preparation of Coating Solution for Toner Image-Receiving
Layer--
[0500] The following components were mixed and stirred to prepare
the coating solution for toner image-receiving layer.
TABLE-US-00018 Aforementioned titanium dioxide dispersion 15.5 g
solution Carnauba wax dispersion solution 15.0 g (Cellosol 524,
available from Chukyo Yushi Co., Ltd.) Polyester resin aqueous
dispersion 100.0 g (solids 30% by mass, KZA-7049, Unitika Ltd.)
Thickener (Alcox E30, MEISEI CHEMICAL 2.0 g WORKS, LTD) Anionic
surfactant (AOT) 0.5 g Ion exchange water 80 ml
[0501] The thus obtained coating solution for toner image-receiving
layer had a viscosity of 40 mPas and a surface tension of 34
mN/m.
--Preparation of Back Layer Coating Solution--
[0502] The following components were mixed and stirred to prepare a
back layer coating solution. TABLE-US-00019 Acrylate resin aqueous
dispersion 100.0 g (solids 30% by mass, High-Loss XBH-997L,
available from Seiko Chemicals) Matting agent 5.0 g (Techpolymer
MBX-12, available from Sekisui Plastics Co., Ltd.) Releasing agent
(Hydrin D337, Chukyo Yushi Co., Ltd.) 10.0 g Thickener (CMC) 2.0 g
Anionic surfactant (AOT) 0.5 g Ion exchange water 80 ml
[0503] The thus obtained back layer coating solution had a
viscosity of 35 mPas and a surface tension of 33 mN/m.
--Coating of Back Layer and Toner Image-Receiving Layer--
[0504] To the backface (namely, the side not to be formed with the
toner image-receiving layer) of the image-recording material
support of each of Example C-1 to Example C-3 and Comparative
Example C-1 to Comparative Example C-2, the back layer coating
solution was applied with a bar coater, such that the coating
amount was 9 g/m.sup.2 in dry mass, to thereby form the back
layer.
[0505] Then, to the surface of the image-recording material
support, the coating solution for toner image-receiving layer was
applied with a bar coater in the same manner as the back layer,
such that the coating amount was 12 g/m.sup.2 in dry mass, to
thereby form the toner image-receiving layer. The content of the
pigment in the toner image-receiving layer was 5% by mass, relative
to the mass of the thermoplastic resin.
[0506] After the back layer coating solution and the toner
image-receiving layer coating solution were coated, they were dried
by hot air, online. Airflow and temperature for drying were
adjusted, so that both the back layer and the toner image-receiving
layer were dried within 2 minutes after the coating. The point of
dryness was determined when the surface temperature of the coating
was equal to the wet-bulb temperature of the airflow for
drying.
[0507] After the drying, a calender treatment was performed. A
gloss calender was used for the calender treatment in which the
temperature of a metal roller was maintained at 40.degree. C. and a
nip pressure was set at 14.7 kN/m.sup.2 (15 kgf/cm.sup.2).
[0508] Each of the thus obtained electrophotographic
image-receiving paper sheets was cut to A4 size, and an image was
printed thereon. The printer used here was a color laser printer
(DocuColor 1250-PF) produced by Fuji Xerox Co., Ltd., excluding
that the fixing belt apparatus 1 shown in FIG. 6 was installed.
[0509] Specifically, in the fixing belt apparatus 1 as shown in
FIG. 6, a fixing belt 2 is suspended around a heating roller 3 and
a tension roller 5. A cleaning roller 6 is provided via the fixing
belt 2 above the tension roller 5, and a pressurizing roller 4 is
further provided via the fixing belt 2 below the heating roller 3.
In FIG. 6, starting from the right-hand side, the
electrophotographic image-receiving paper sheet carrying a toner
latent image was introduced between the heating roller 3 and the
pressurizing roller 4, was fixed and then transported on the fixing
belt 2. Thereafter, in this process, the electrophotographic
image-receiving paper sheet was cooled by a cooling device 7, and
the fixing belt 2 was finally cleaned by a cleaning roller 6.
[0510] In the fixing belt apparatus 1, the transport speed at the
fixing belt 2 is 30 mm/sec, the nip pressure between the heating
roller 3 and the pressurizing roller 4 was 0.2 MPa (2
kgf/cm.sup.2), and the temperature of the heating roller 3 was
150.degree. C. which corresponded to the fixing temperature. The
temperature of the pressurizing roller 4 was set at 120.degree.
C.
[0511] For each electrophotographic print thus obtained, image
quality and gloss were evaluated in the following manner. The
results are shown in Table 11.
<Evaluation of Image Quality>
[0512] The image quality of each electrophotographic print was
visually observed and was evaluated. The print with the best image
quality was assigned A, followed by B, C, D and E on the following
basis.
[Evaluation Standards]
[0513] A: Very good (Effective for high image quality recording
material).
[0514] B: Good (Effective for high image quality recording
material).
[0515] C: Mediocre (Ineffective for high image quality recording
material).
[0516] D: Poor (Ineffective for high image quality recording
material).
[0517] E: Very poor (Ineffective for high image quality recording
material).
<Evaluation of Gloss>
[0518] The gloss of each electrophotographic print was visually
observed and was evaluated. The print with the best gloss was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0519] A: Very good (Effective for high image quality recording
material).
[0520] B: Good (Effective for high image quality recording
material).
[0521] C: Mediocre (Ineffective for high image quality recording
material).
[0522] D: Poor (Ineffective for high image quality recording
material).
[0523] E: Very poor (Ineffective for high image quality recording
material). TABLE-US-00020 TABLE 11 Image Support Gloss quality
Example C-4 Example C-1 A A Example C-5 Example C-2 A B Example C-6
Example C-3 B A Comparative Comparative D D Example C-3 Example C-1
Comparative Comparative C D Example C-4 Example C-2
Example C-7 to Example C-9 and Comparative Example C-5 to
Comparative Example C-6
--Preparation of Photographic Printing Paper--
[0524] With the image-recording material supports prepared in
Example C-1 to Example C-3 and Comparative Example C-1 to
Comparative Example C-2, gelatin 0.1 g/m.sup.2 was applied to the
side (surface) to be formed with the image-recording layer. The
thus obtained gelatin coat face was further coated with the
overlapping coatings in the following order of: i) silver halide
gelatin emulsion layer (10 g/m.sup.2) for yellow coloring
photograph, ii) gelatin intermediate layer, iii) silver halide
gelatin emulsion layer (10 g/m.sup.2) for magenta coloring
photograph, iv) gelatin intermediate layer, v) silver halide
gelatin emulsion layer (10 g/m.sup.2) for cyanogen coloring
photograph, and vi) gelatin protective layer, to thereby prepare
the photographic printing paper sheets, respectively, of Example
C-7 to Example C-9 and Comparative Example C-5 to Comparative
Example C-6.
[0525] The photographic printing papers thus obtained were exposed
and developed to prepare photographic prints. For each photographic
print, surface smoothness (small-scale irregularity (1 mm or less)
and large-scale irregularity (5 mm to 6 mm)) was evaluated in the
following manner. The results are shown in Table 12.
<Surface Smoothness (Small-Scale Irregularity (1 mm or
Less))>
[0526] The surface appearance of each photographic print was
visually observed and was evaluated. The print with the best
surface smoothness (small-scale irregularity (1 mm or less)) was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0527] A: Very good (Effective for high image quality recording
material).
[0528] B: Good (Effective for high image quality recording
material).
[0529] C: Mediocre (Ineffective for high image quality recording
material).
[0530] D: Poor (Ineffective for high image quality recording
material).
[0531] E: Very poor (Ineffective for high image quality recording
material).
<Surface Smoothness (Large-Scale Irregularity (5 mm to 6
mm))>
[0532] The surface appearance of each photographic print was
visually observed and was evaluated. The print with the best
surface smoothness (large-scale irregularity (5 mm to 6 mm)) was
assigned A, followed by B, C, D and E on the following basis.
[Evaluation Standards]
[0533] A: Very good (Effective for high image quality recording
material).
[0534] B: Good (Effective for high image quality recording
material).
[0535] C: Mediocre (Ineffective for high image quality recording
material).
[0536] D: Poor (Ineffective for high image quality recording
material).
[0537] E: Very poor (Ineffective for high image quality recording
material). TABLE-US-00021 TABLE 12 Surface smoothness Small-scale
Large-scale irregularity irregularity Support (1 mm or less) (5 mm
to 6 mm) Example C-7 Example C-1 A A Example C-8 Example C-2 A B
Example C-9 Example C-3 A A Comparative Comparative D C Example C-5
Example C-1 Comparative Comparative C D Example C-6 Example C-2
[0538] Under the present invention, an image-recording material
support can be provided which has high planarity and excellent
gloss. Moreover under the present invention, an image-recording
material can be provided which allows an image-recording face after
image-recording to have high-quality image and high gloss, and
cause a small curl.
* * * * *