U.S. patent application number 14/396465 was filed with the patent office on 2015-04-02 for wood pulp for glass plate-interleaving paper and glass plate-interleaving paper.
This patent application is currently assigned to Tokushu Tokai Paper Co., Ltd.. The applicant listed for this patent is TOKUSHU TOKAI PAPER CO., LTD.. Invention is credited to Shinichi Akahori, Yasuhiko Asai, Tomoki Hirasawa, Yoshiaki Tomotake.
Application Number | 20150090413 14/396465 |
Document ID | / |
Family ID | 51021261 |
Filed Date | 2015-04-02 |
United States Patent
Application |
20150090413 |
Kind Code |
A1 |
Asai; Yasuhiko ; et
al. |
April 2, 2015 |
WOOD PULP FOR GLASS PLATE-INTERLEAVING PAPER AND GLASS
PLATE-INTERLEAVING PAPER
Abstract
The present invention relates to wood pulp for glass
plate-interleaving paper in which an amount of silicone contained
in the wood pulp is 0.5 ppm or less with respect to an absolute dry
mass of the pulp, as well as relates to interleaving paper for
glass plates of which a raw material is the wood pulp, in which an
amount of silicone contained in paper is 0.5 ppm or less with
respect to the absolute dry matter of paper. The interleaving paper
for glass plates formed from the wood pulp of the present
invention, as well as interleaving paper for glass plates of the
present invention are able to remarkably control contamination of
silicone to the surface of glass plates for use as substrate
material for flat panel displays for which a high degree of
cleanliness and high quality are required.
Inventors: |
Asai; Yasuhiko; (Shizuoka,
JP) ; Akahori; Shinichi; (Shizuoka, JP) ;
Hirasawa; Tomoki; (Shizuoka, JP) ; Tomotake;
Yoshiaki; (Shizuoka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TOKUSHU TOKAI PAPER CO., LTD. |
Shimada-shi, Shizuoka |
|
JP |
|
|
Assignee: |
Tokushu Tokai Paper Co.,
Ltd.
Shimada-shi,
JP
|
Family ID: |
51021261 |
Appl. No.: |
14/396465 |
Filed: |
December 26, 2013 |
PCT Filed: |
December 26, 2013 |
PCT NO: |
PCT/JP2013/084874 |
371 Date: |
October 23, 2014 |
Current U.S.
Class: |
162/72 ;
162/158 |
Current CPC
Class: |
B65G 2249/02 20130101;
C03B 40/033 20130101; B65G 57/005 20130101; D21H 11/04 20130101;
Y02P 40/57 20151101; D21H 21/12 20130101; D21H 17/59 20130101; B65G
57/02 20130101; D21H 17/13 20130101; D21H 27/10 20130101 |
Class at
Publication: |
162/72 ;
162/158 |
International
Class: |
D21H 17/59 20060101
D21H017/59 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 27, 2012 |
JP |
2012-285315 |
Apr 18, 2013 |
JP |
2013-087570 |
Claims
1. Wood pulp for glass plate-interleaving paper wherein an amount
of silicone contained in the wood pulp is 0.5 ppm or less with
respect to an absolute dry mass of the wood pulp.
2. The wood pulp for glass plate-interleaving paper according to
claim 1, wherein an amount of silicone contained in wood pulp is
0.1 ppm or less with respect to an absolute dry mass of the wood
pulp.
3. The wood pulp for glass plate-interleaving paper according to
claim 1, wherein said silicone is a silicone oil.
4. The wood pulp for glass plate-interleaving paper according to
claim 3, wherein said silicone oil is a dimethylpolysiloxane.
5. The wood pulp for glass plate-interleaving paper according to
claim 1, wherein said glass plate is for use in a display.
6. The wood pulp for glass plate-interleaving paper according to
claim 5, wherein said display is a TFT liquid crystal display or an
organic EL display.
7. Glass plate-interleaving paper formed from the wood pulp for
glass plate-interleaving paper recited in claim 1.
8. Interleaving paper for glass plates, of which a raw material is
wood pulp, wherein an amount of silicone contained in paper is 0.5
ppm or less with respect to an absolute dry matter of paper.
9. The interleaving paper for glass plates according to claim 8,
wherein an amount of silicone contained in paper is 0.1 ppm or less
with respect to an absolute dry matter of paper.
10. The interleaving paper for glass plates according to claim 8,
wherein said silicone is a silicone oil.
11. The interleaving paper for glass plates according to claim 10,
wherein said silicone oil is a dimethylpolysiloxane.
12. The interleaving paper for glass plates according to claim 8,
wherein said glass plate if for use in a display.
13. The interleaving paper for glass plates according to claim 12,
wherein said display is a TFT liquid crystal display or an organic
EL display.
14. A laminate of glass plates and the glass plate-interleaving
paper as recited in claim 7.
15. Use of the wood pulp as claimed in claim 1 for the manufacture
of glass plate-interleaving paper.
Description
TECHNICAL FIELD
[0001] The present invention relates to package paper for packaging
glass plates and interleaving paper to be inserted between glass
plates, used in the process of storing and transporting glass
plates for use in flat panel displays such as liquid crystal
displays, plasma displays, organic electroluminescence (organic EL)
displays and the like, in a laminated state, as well as relates to
wood pulp for use in manufacturing paper mentioned above.
BACKGROUND ART
[0002] In general, during the course of storage of glass plates for
flat panel displays in a laminated state, or during the course of
distribution of transporting them by trucks and the like, paper
which is so-called interleaving paper has been inserted between
glass plates in order to prevent occurrences of abrasion by
contacting glass plates on impact or prevent contamination of the
surface of glass plates.
[0003] Glass plates for flat panel displays are used for
high-definition displays, which are different from common
architectural glass plates, vehicular glass plates, and the like.
For this reason, the surface of glass plates for flat panel
displays requires maintaining a clean surface so that contamination
of the glass surface due to impurities contained on the surface of
paper is extremely reduced, and requires having a superior flatness
for a fast-response property or wide viewing angle.
[0004] Some types of interleaving paper for such a usage, for
example, interleaving paper in which cracking of glass plates or
surface abrasion can be prevented, and interleaving paper in which
the surface of glass plates is not contaminated, have been
proposed. For example, Patent Document 1 discloses a method of
forming a fluorine coating film on the surface of interleaving
paper. In addition, Patent Document 2 discloses interleaving paper
to which a foamed sheet made of a polyethylene-based resin and a
film made of a polyethylene-based resin are applied. Patent
Document 3 discloses interleaving paper for glass plates, which is
formed from pulp containing 50% by mass or more of bleached
chemical pulp, and includes a specific alkylene oxide adduct and a
water-soluble polyether-modified silicone. In addition, Patent
Document 4 discloses interleaving paper for glass plates in which a
resin content in paper is specified, and a raw material selected in
view of contamination of the surface of glass is used.
PRIOR ART DOCUMENTS
Patent Documents
[0005] Patent Document 1: Japanese Unexamined Patent Application,
First Publication No. 2012-188785 [0006] Patent Document 2:
Japanese Unexamined Patent Application, First Publication No.
2010-242057 [0007] Patent Document 3: Japanese Unexamined Patent
Application, First Publication No. 2008-208478 [0008] Patent
Document 4: Japanese Unexamined Patent Application, First
Publication No. 2006-44674
DISCLOSURE OF INVENTION
Technical Problems
[0009] However, the interleaving paper mentioned above could not
completely prevent contamination of the surface of glass plates for
flat panel displays. In some cases, a failure rate of glass plates
may be actually increased due to contamination of the surface of
glass plates for some reasons.
[0010] In particular, in view of profitability, recently an
increased yield is required in the process of manufacturing flat
panel displays and the like, and how to prevent contamination of
the surface of glass plates for flat panel displays is
important.
[0011] The present invention has an object to provide interleaving
paper which can remarkably prevent contamination on the surface of
glass plates for use as substrate materials for flat panel displays
for which a high degree of cleanliness and high quality without
damages are required, as well as provide wood pulp for the
interleaving paper mentioned above.
Technical Solution
[0012] For example, it is known that if the surface of a glass
plate is contaminated at the time of manufacturing a color filter
substrate in an array process which is one of processes of
manufacturing TFT liquid crystal displays, a problem such as
disconnection or the like occurs. A color filter substrate is
manufactured by forming a thin film such as a semiconductor film,
an ITO film (transparent conductive film), an insulating film, an
aluminum metal film or the like on a glass plate by means of
sputtering, vacuum deposition method or the like. If contaminants
exist on the surface of a glass plate, disconnection occurs in a
circuit pattern formed from a thin film or short circuit caused by
defects of an insulating film occurs. In addition, during
manufacture of a color filter substrate, a pattern is formed on a
glass plate by means of photolithography. If contaminants are
present on the surface of the glass plate at the time of resist
application in the aforementioned process, a pinhole is formed on
the resist film after exposure or development, and as a result,
disconnection or short circuit occurs. The same problems as
described above are confirmed in the manufacture of organic EL
displays. An organic EL display is manufactured by forming a thin
film such as an ITO positive electrode, an organic emitting layer,
a negative electrode and the like on a glass plate by means of
sputtering, vapor deposition, printing or the like. For this
reason, if a contaminant inhibiting the formation of a thin film
exists on the surface of a glass plate, a problem of becoming
non-luminescent occurs. It was difficult to specify a causality of
such a contamination of a glass plate. It was first revealed in
verification carried out by the inventors of the present
application that the causality is silicone contained in the
interleaving paper for glass plates.
[0013] The inventors of the present application discovered that the
problems mentioned above can be overcome by setting an amount of
silicone contained in wood pulp which is used in the manufacture of
interleaving paper for glass plates (hereinafter, also referred to
as "glass plate-interleaving paper") to a specified amount or less,
and setting an amount of silicone contained in interleaving paper
for glass plates to a specified amount or less, thus completing the
present invention.
[0014] That is, a first mode of the present invention relates to
wood pulp for glass plate-interleaving paper in which an amount of
silicone contained in wood pulp is 0.5 ppm or less with respect to
the absolute dry mass of the wood pulp.
[0015] The amount of a silicone contained in wood pulp is
preferably 0.1 ppm or less with respect to the absolute dry mass of
the wood pulp.
[0016] The silicone mentioned above is preferably a silicone
oil.
[0017] The silicone oil mentioned above is preferably a
dimethylpolysiloxane.
[0018] The glass plate mentioned above is preferably one for use in
a display, and in particular, the display is preferably a TFT
liquid crystal display or an organic EL display.
[0019] A second mode of the present invention relates to
interleaving paper for glass plates, of which a raw material is
wood pulp, and in which the amount of silicone contained in paper
is 0.5 ppm or less with respect to the absolute dry matter of
paper.
[0020] The amount of silicone contained in interleaving paper for
glass plates is preferably 0.1 ppm or less with respect to the
absolute dry matter of paper.
[0021] The silicone mentioned above is preferably a silicone
oil.
[0022] The silicone oil mentioned above is preferably a
dimethylpolysiloxane.
[0023] The glass plate mentioned above is preferably for a display,
and in particular, the display is preferably a TFT liquid crystal
display or an organic EL display.
[0024] In addition, the present invention also relates to a
laminate of glass plates, and the aforementioned glass
plate-interleaving paper formed from the aforementioned wood pulp
according to the first mode and/or the aforementioned interleaving
paper for glass plates according to the second mode.
[0025] Furthermore, the present invention also relates to use of
the aforementioned wood pulp according to the first mode of the
present invention for the manufacture of glass plate-interleaving
paper, and in particular, glass plate-interleaving paper according
to the second mode of the present invention.
Effects of the Invention
[0026] The glass plate-interleaving paper formed from wood pulp of
the present invention, as well as interleaving paper for glass
plates of the present invention can control or inhibit the transfer
of silicone to glass plates. By controlling or inhibiting the
transfer of silicone to glass plates as described above, circuit
disconnection of a color film or the like in a process of
manufacturing a TFT liquid crystal display and the like can be
prevented.
MODES FOR CARRYING OUT THE INVENTION
[0027] When interleaving paper is used for glass plates, the
silicone contained in interleaving paper tends to be transferred to
glass plates. In particular, it has been clarified at present that
if interleaving paper formed from wood pulp in which an amount of
silicone exceeds 0.5 ppm, or interleaving paper in which an amount
of silicone exceeds 0.5 ppm is used, the amount of the silicone
transferred to glass plates is extremely increased, and as a
result, this causes a problem at the time of forming a panel.
Therefore, in the wood pulp for glass plate-interleaving paper of
the present invention, an amount of silicone contained in wood pulp
is 0.5 ppm or less with respect to the absolute dry mass of wood
pulp. Thereby, the amount of silicone contained in glass
plate-interleaving paper formed from wood pulp of the present
invention can be set to 0.5 ppm or less. In addition, the
interleaving paper for glass plates of the present invention is
interleaving paper for glass plates formed from wood pulp, in which
an amount of silicone contained in paper is 0.5 ppm or less with
respect to the absolute dry matter of paper. Term "absolute dry"
matter in the present invention means a state in which after drying
an object to be dried, moisture does not substantially exist in the
object. For example, a weight change per hour at room temperature
(25.degree. C.) of an object in an "absolute dry" state is 1% or
less, preferably 0.5% or less, and more preferably 0.1% by
less.
[0028] In general, silicone is contained in wood pulp in many
cases. This may be caused by frequently using a silicone-based
defoamer as a defoamer used in order to prevent the reduction of a
cleansing ability due to generation of foam during a process of
manufacturing wood pulp, and in particular, during a cleansing
process. Silicone originated from the silicone-based defoamer
mentioned above remains in pulp. A silicone-based defoamer is
produced by, for example, mixing a modified silicone, a surfactant
and the like in a mixture of a silicone oil and a hydrophobic
silica.
[0029] Therefore, in order to set an amount of silicone contained
in glass plate-interleaving paper to 0.5 ppm or less, in
particular, it is important that wood pulp as a raw material of
interleaving paper does not contain a large amount of silicone. In
the first mode of the present invention, although means for setting
the amount of silicone contained in wood pulp as a raw material of
interleaving paper to 0.5 ppm or less is not particularly limited,
a non-silicone-based defoamer is preferably used as a deformer used
during the manufacture of wood pulp.
[0030] Examples of a non-silicone-based defoamer include, for
example, an inorganic oil-based defoamer, a higher alcohol-based
defoamer, a fatty acid-based defoamer, a fatty acid ester-based
defoamer, an amide-based defoamer, an amine-based defoamer, a
phosphoric ester-based defoamer, a metallic soap-based defoamer, a
sulfonic ester-based defoamer, a polyether-based defoamer, and a
plant oil-based defoamer.
[0031] Examples of an inorganic oil-based defoamer include, for
example, an inorganic oil such as a hydrocarbon oil or the like, an
inorganic wax, and the like.
[0032] Examples of a higher alcohol-based defoamer include, for
example, octyl alcohol, hexadecyl alcohol, and the like.
[0033] Examples of a fatty acid-based defoamer include, for
example, palmitic acid, oleic acid, stearic acid, and the like.
[0034] Examples of a fatty acid ester-based defoamer include, for
example, isoamyl stearate, glycerol monolicinolate, sorbitol
monolaurate, sorbitol trioleate, and the like.
[0035] Examples of an amide-based defoamer include, for example,
acrylate polyamine and the like.
[0036] Examples of an amine-based defoamer include, for example,
diallylamine and the like.
[0037] Examples of a phosphoric ester-based defoamer include, for
example, tributyl phosphate, sodium octylphosphate, and the
like.
[0038] Examples of a metallic soap-based defoamer include, for
example, aluminum stearate, calcium stearate, potassium oleate, and
the like.
[0039] Examples of a sulfonic ester-based defoamer include, for
example, sodium laurylsulfonate, sodium dodecylsulfonate, and the
like.
[0040] Examples of a polyether-based defoamer include, for example,
a polyoxyalkylene such as a (poly)oxyethylene (poly)oxypropylene
adduct, or the like; a (poly)oxyalkylene alkyl ether such as
diethylene glycol heptyl ether, polyoxyethylene oleyl ether,
polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene
2-ethylhexyl ether, an oxyethylene oxypropylene adduct to a higher
alcohol having 8 or more carbon atoms or a secondary alcohol having
12 to 14 carbon atoms, or the like; a (poly)oxyalkylene (alkyl)
aryl ether such as polyoxypropylene phenyl ether, polyoxyethylene
nonyl phenyl ether or the like; an acetylene ether obtained by
subjecting an acetylene alcohol such as
2,4,7,9-tetramethyl-5-decyne-4,7-diol,
2,5-dimethyl-3-hexyne-2,5-diol, 3-methyl-1-butyne-3-ol or the like
to alkylene oxide-addition polymerization; a (poly)oxyalkylene
fatty acid ester such as diethylene glycol oleic ester, diethylene
glycol lauric ester, ethylene glycol distearic ester or the like; a
(poly)oxyalkylene sorbitan fatty acid ester such as polyoxyethylene
sorbitan monolaurate, polyoxyethylene sorbitan trioleate, or the
like; a (poly)oxyalkylene alkyl(aryl)ether sulfuric ester salt such
as sodium polyoxypropylene methyl ether sulfate, sodium
polyoxyethylene dodecyl phenol ether sulfate or the like; a
(poly)oxyalkylene alkyl phosphoric ester such as (poly)oxyethylene
stearyl phosphoric ester or the like; a (poly)oxyalkylene
alkylamine such as polyoxyethylene laurylamine or the like;
polyoxyalkylene amide and the like.
[0041] Examples of a plant oil-based defoamer include, for example,
plant oils such as soybean oil, corn oil, coconut oil, linseed oil,
rape seed oil, cotton seed oil, sesame oil, castor oil and the
like.
[0042] In addition, a non-silicone-based defoamer can include
inorganic particles such as hydrophobic silica and the like. As a
hydrophobic silica, a hydrophobically treated silica obtained by
replacing a silanol group of a hydrophilic silica with an alkyl
group such as a methyl group, is preferably used.
[0043] A non-silicone-based defoamer can also contain a surfactant
and the like, if necessary. Therefore, a non-silicone-based
defoamer may be in the form of an emulsion.
[0044] Wood pulp usable in the present invention is wood pulp such
as nadelholz bleached kraft pulp (NBKP), laubholz bleached kraft
pulp (LBKP), nadelholz bleached sulfite pulp (NBSP), laubholz
bleached sulfite pulp (LBSP), thermomechanical pulp (TMP) or the
like, alone or in combination thereof. Non-wood pulp formed from
marijuana, bamboo, straw, kenaf, paper mulberry, paper birch,
cotton or the like, modified pulp such as cationated pulp,
mercerized pulp or the like, synthetic fiber or chemical fiber such
as rayon, vinylon, nylon, acryl, polyester or the like, or
microfibrillated pulp can be blended alone or in combination
thereof into the aforementioned wood pulp as a main component.
However, if a large amount of a resin component is contained in
pulp, the resin component mentioned above may exhibit an adverse
effect such as contamination of the surface of glass plates or the
like. For this reason, chemical pulp with a reduced amount of a
resin component as possible, such as nadelholz bleached kraft pulp,
is preferably used alone. In addition, high yield pulp such as
ground wood pulp contains a large amount of a resin component, and
therefore, this is not preferable. When synthetic fiber or chemical
fiber is mixed together therewith, a cutting property is improved
and an operation property during forming interleaving paper into a
flat plate form is improved. However, it should be noted that the
recycling property in view of treatment of waste is impaired in
this case.
[0045] In addition, an adhesive, an antifungal agent, various
loading materials for making paper, a wet paper strengthening
agent, a dry paper strengthening agent, a sizing agent, a coloring
agent, a fixing agent, a yield improver, slime controller, and the
like may be added to fiber for making paper which contains the
aforementioned wood pulp as a main component, within a scope which
does not impair the performance of the present invention, if
necessary. Subsequently, the mixture can be subjected to making
paper by means of a conventionally known Fourdrinier paper machine,
cylinder paper machine, tanmo machine, combination machine between
Fourdrinier paper machine and cylinder paper machine, or the like.
It requires scrupulous care to prevent contamination of insects or
contaminants during addition of the aforementioned chemicals.
[0046] If beating of pulp is carried out, when the wood pulp of the
present invention is manufactured, an effect of increasing strength
between paper layers can be expected. However, if due to carrying
out beating of pulp, microfiber in the wood pulp increases, paper
powder may be generated during use as interleaving paper. For this
reason, increasing the beating degree to a more than necessary
degree is not preferable. Therefore, a preferable beating degree in
the present invention ranges from 300 to 650 ml c.s.f.
[0047] In the present invention, the amount of silicone contained
in wood pulp or in glass plate-interleaving paper formed from the
aforementioned wood pulp is preferably 0.4 ppm or less, more
preferably 0.3 ppm or less, even more preferably 0.2 ppm or less,
and in particular, preferably 0.1 ppm or less, with respect to the
absolute dry matter of wood pulp or paper. If silicone is present
in an amount exceeding 0.1 ppm, in the case of needing a very
high-definition display for a mobile terminal and the like, the
parts with circuit disconnection of a color film caused by a trace
amount of silicone transferred onto glass may be highly visible
because of high definition, and therefore, the display may be
judged to be poor in quality.
[0048] Glass plate-interleaving paper, and in particular, glass
plate-interleaving paper of the present invention can be obtained
by using wood pulp of the present invention in accordance with a
conventional method. During and/or after manufacture of glass
plate-interleaving paper, a processing treatment such as a calender
treatment, a super calender treatment, a softnip calender
treatment, an emboss treatment or the like may be carried out. By
carrying out a processing treatment, a surface property or the
thickness can be adjusted.
[0049] As examples of silicone in the present invention, a silicone
oil may be mentioned. A silicone oil is hydrophobic, and the
molecular structure thereof may be in any form of a cyclic form, a
linear form, or a branched form. A kinetic viscosity of a silicone
oil at 25.degree. C. usually ranges from 0.65 to 100,000
mm.sup.2/s, and may range from 0.65 to 10,000 mm.sup.2/s.
[0050] Examples of a silicone oil include, for example, a linear
organopolysiloxane, a cyclic organopolysiloxane, and a branched
organopolysiloxane.
[0051] Examples of a linear organopolysiloxane, a cyclic
organopolysiloxane, and a branched organopolysiloxane include, for
example, organopolysiloxanes represented by the following general
formulae (1), (2) and (3):
##STR00001##
(wherein each R.sup.1 is independently a hydrogen atom, a hydroxyl
group, or a group selected from a substituted or unsubstituted
monovalent hydrocarbon group and an alkoxy group; a is an integer
ranging from 0 to 1,000; b is an integer ranging from 3 to 100; and
c is an integer ranging from 1 to 4, and is preferably an integer
ranging from 2 to 4).
[0052] The substituted or unsubstituted monovalent hydrocarbon
group is typically a monovalent saturated hydrocarbon group having
1 to 30 carbon atoms, preferably having 1 to 10 carbon atoms, and
more preferably having 1 to 4 carbon atoms, which may be
substituted or unsubstituted; a monovalent unsaturated hydrocarbon
group having 2 to 30 carbon atoms, preferably having 2 to 10 carbon
atoms, and more preferably having 2 to 6 carbon atoms, which may be
substituted or unsubstituted; and a monovalent aromatic hydrocarbon
group having 6 to 30 carbon atoms, and more preferably having 6 to
12 carbon atoms, which may be substituted or unsubstituted.
[0053] Examples of a monovalent saturated hydrocarbon group having
1 to 30 carbon atoms include, for example, a linear or branched
alkyl group such as a methyl group, an ethyl group, a n-propyl
group, an isopropyl group, a n-butyl group, an isobutyl group, a
sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group,
a heptyl group, an octyl group, a nonyl group, a decyl group or the
like, as well as a cycloalkyl group such as a cyclopentyl group, a
cyclohexyl group, a cycloheptyl group, a cyclooctyl group or the
like.
[0054] Examples of a monovalent unsaturated hydrocarbon group
having 2 to 30 carbon atoms include, for example, a linear or
branched alkenyl group such as a vinyl group, a 1-propenyl group,
an allyl group, an isopropenyl group, a 1-butenyl group, a
2-butenyl group, a pentenyl group, a hexenyl group or the like; a
cycloalkenyl group such as a cyclopentenyl group, a cyclohexenyl
group or the like; a cycloalkenylalkyl group such as a
cyclopentenylethyl group, a cyclohexenylethyl group, a
cyclohexenylpropyl group, or the like; and an alkynyl group such as
an ethynyl group, a propargyl group or the like.
[0055] Examples of a monovalent aromatic hydrocarbon group having 6
to 30 carbon atoms include, for example, an aryl group such as a
phenyl group, a tolyl group, a xylyl group, a mesityl group or the
like. A phenyl group is preferable. The aromatic hydrocarbon group
in the specification of the present application includes a group in
which an aromatic hydrocarbon and an aliphatic saturated
hydrocarbon are combined, in addition to a group consisting of only
an aromatic hydrocarbon. Examples of a group in which an aromatic
hydrocarbon and an aliphatic saturated hydrocarbon are combined
include, for example, an aralkyl group such as a benzyl group, a
phenethyl group or the like.
[0056] The hydrogen atoms on the aforementioned monovalent
hydrocarbon group may be substituted by one or more substituents.
The aforementioned substituents can be selected from, for example,
a halogen atom (a fluorine atom, a chlorine atom, a bromine atom,
and an iodine atom), a hydroxyl group, and an organic group
containing a carbinol group, an epoxy group, a glycidyl group, an
acyl group, a carboxyl group, an amino group, a methacryl group, a
mercapto group, an amide group, an oxyalkylene group, and the like.
More particularly, examples thereof include a 3,3,3-trifluoropropyl
group, a 3-chloropropyl group, a 3-hydroxypropyl group, a
3-(2-hydroxyethoxy)propyl group, a 3-carboxypropyl group, a
10-carboxydecyl group, a 3-isocyanatepropyl group, and the
like.
[0057] As an alkoxy group, examples thereof include a methoxy
group, an ethoxy group, a propoxy group and the like. A methoxy
group or an ethoxy group is preferable, and a methoxy group is more
preferable.
[0058] More particularly, examples of a linear organopolysiloxane
include a dimethylpolysiloxane in which both terminals of the
molecular chain are capped with trimethylsiloxy groups (from a
dimethylsilicone with a low viscosity such as 2 mPas, 6 mPas or the
like, to a dimethylsilicone with a high viscosity such as 1,000,000
mPas or the like), an organohydrogenpolysiloxane, a
methylphenylpolysiloxane in which both terminals of the molecular
chain are capped with trimethylsiloxy groups, a copolymer of
methylphenylsiloxane and dimethylsiloxane in which both terminals
of the molecular chain are capped with trimethylsiloxy groups, a
diphenylpolysiloxane in which both terminals of the molecular chain
are capped with trimethylsiloxy groups, a copolymer of
diphenylsiloxane and dimethylsiloxane in which both terminals of
the molecular chain are capped with trimethylsiloxy group,
trimethylpentaphenyltrisiloxane, phenyl(trimethylsiloxy)siloxane, a
methylalkylpolysiloxane in which both terminals of the molecular
chain are capped with trimethylsiloxy groups, a copolymer of
methylaklylsiloxane and dimethylpolysiloxane in which both
terminals of the molecular chain are capped with trimethylsiloxy
groups, a copolymer of methyl(3,3,3-trifluoropropyl)siloxane and
dimethylsiloxane in which both terminals of the molecular chain are
capped with trimethylsiloxy groups, an
.alpha.,.omega.-dihydroxypolydimethylsiloxane, an
.alpha.,.omega.-diethoxypolydimethylsiloxane,
1,1,1,3,5,5,5-heptamethyl-3-octamethyltrisiloxane,
1,1,1,3,5,5,5-heptamethyl-3-dodecyltrisiloxane,
1,1,1,3,5,5,5-heptamethyl-3-hexadecyltrisiloxane,
tristrimethylsiloxymethylsilane, a tristrimethylsiloxyalkylsilane,
tetrakistrimethylsiloxysilane, tetramethyl-1,3-dihydroxydisiloxane,
octamethyl-1,7-dihydroxytetrasiloxane,
hexamethyl-1,5-diethoxytrisiloxane, hexamethyldisiloxane,
octamethyltrisiloxane, a higher alkoxy-modified silicone, a higher
fatty acid-modified silicone, dimethiconol, and the like.
[0059] Examples of a cyclic organopolysiloxane includes
hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4),
decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane
(D6), 1,1-diethylhexamethylcyclotetrasiloxane,
phenylheptamethylcyclotetrasiloxane,
1,1-diphenylhexamethylcyclotetrasiloxane,
1,3,5,7-tetravinyltetramethylcyclotetrasiloxane,
1,3,5,7-tetramethylcyclotetrasiloxane,
1,3,5,7-tetracyclohexyltetramethylcyclotetrasiloxane,
tris(3,3,3-trifluoropropyl)trimethylcyclotrisiloxane,
1,3,5,7-tetra(3-methacryloxypropyl)tetramethylcyclotetrasiloxane,
1,3,5,7-tetra(3-acryloxypropyl)tetramethylcyclotetrasiloxane,
1,3,5,7-tetra(3-carboxypropyl)tetramethylcyclotetrasiloxane,
1,3,5,7-tetra(3-vinyloxypropyl)tetramethylcyclotetrasiloxane,
1,3,5,7-tetra(p-vinylphenyl)tetramethylcyclotetrasiloxane,
1,3,5,7-tetra[3-(p-vinylphenyl)propyl]tetramethylcyclotetrasiloxane,
1,3,5,7-tetra(N-acryloyl-N-methyl-3-aminopropyl)tetramethylcyclotetrasilo-
xane,
1,3,5,7-tetra(N,N-bis(lauroyl)-3-aminopropyl)tetramethylcyclotetrasi-
loxane, and the like.
[0060] Examples of a branched organopolysiloxane include
methyltristrimethylsiloxysilane, ethyltristrimethylsiloxysilane,
propyltristrimethylsiloxysilane, tetrakistrimethylsiloxysilane,
phenyltristrimethylsiloxysilane, and the like.
[0061] As a silicone oil in the present invention,
dimethylpolysiloxane, diethylpolysiloxane,
methylphenylpolysiloxane, a polydimethyl polydiphenylsiloxane
copolymer, polymethyl-3,3,3-trifluoropropylsiloxane and the like
are preferable. As a silicone in the present invention,
dimethylpolysiloxane is typically used.
[0062] A silicone oil in the present invention may be a modified
silicone oil. Examples of a modified silicone oil include, for
example, a polyoxyalkylene-modified silicone oil.
[0063] A polyoxyalkylene-modified silicone oil is a silicone oil in
which a polyoxyalkylene group is bonded via a silicon-carbon bond
in a molecule, preferably exhibits a water-solubility at 25.degree.
C., and is more preferably a nonion-based one.
[0064] A polyoxyalkylene-modified silicone oil is, in particular, a
copolymer between a polyoxyalkylene and a silicone oil formed from
a linear or branched siloxane, for example. There are various types
thereof. In particular, the silicone oils represented by the
following formula (4) are preferable.
R.sup.2.sub.3SiO--(R.sup.1.sub.2SiO).sub.d--(R.sup.1ASiO).sub.e--SiR.sup-
.2.sub.3 (4)
(wherein each R.sup.1 is independently the same as described above,
each R.sup.2 is independently R.sup.1 or A, each A is independently
a group represented by R.sup.3G, in which R.sup.3 is a substituted
or unsubstituted divalent hydrocarbon group, and G represents a
polyoxyalkylene group containing at least one type of an alkylene
oxide having 2 to 5 carbon atoms such as ethylene oxide, propylene
oxide or the like, d represents an integer ranging from 1 to 500,
and e represents an integer ranging from 1 to 50).
[0065] Examples of a substituted or unsubstituted divalent
hydrocarbon group include, for example, a linear or branched
divalent hydrocarbon group, examples of which include a linear or
branched alkylene group having 1 to 30 carbon atoms such as a
methylene group, a dimethylene group, a trimethylene group, a
tetramethylene group, a pentamethylene group, a hexamethylene
group, a heptamethylene group, an octamethylene group, or the like;
an alkenylene group having 2 to 30 carbon atoms such as a vinylene
group, an allylene group, a butenylene group, a hexenylene group,
an octenylene group, or the like; an arylene group having 6 to 30
carbon atoms such as a phenylene group, a diphenylene group or the
like; an alkylene arylene group having 7 to 30 carbon atoms such as
a dimethylene phenylene group or the like; and a group in which
hydrogen atoms binding to carbon atoms of the aforementioned groups
are at least partially substituted with a halogen atom such as a
fluorine atom or the like, a hydroxyl group, or an organic group
containing a carbinol group, an epoxy group, a glycidyl group, an
acyl group, a carboxyl group, an amino group, a methacryl group, a
mercapto group, an amide group, an oxyalkylene group or the like.
The divalent hydrocarbon group is preferably an alkylene group
having 1 to 30 carbon atoms, preferably an alkylene group having 1
to 6 carbon atoms, and more preferably an alkylene group having 3
to 5 carbon atoms.
[0066] For example, as examples of a polyoxyalkylene-modified
silicone oil, the following compounds can be mentioned.
##STR00002##
(wherein x ranges from 20 to 160, y ranges from 1 to 25, and a
value of x/y ranges from 50 to 2, A is, for example,
--(CH.sub.2).sub.3O--(CH.sub.2CH.sub.2O).sub.m--(CH.sub.2CH.sub.2CH.sub.2-
O).sub.n--R.sup.4, m ranges from 7 to 40, n ranges from 0 to 40, a
value of m+n is at least 1, A may be a graft-polymerized one or a
random-polymerized one, and R.sup.4 represents a hydrogen atom or
the aforementioned substituted or unsubstituted monovalent
hydrocarbon group. Preferably, m ranges from 7 to 30 and n ranges
from 0 to 30).
[0067] In addition, as an example of a modified silicone oil, for
example, an aminoalkyl-modified silicone oil may be mentioned.
[0068] An aminoalkyl-modified silicone oil is a silicone oil in
which an aminoalkyl group is bonded to the molecule via a
silicon-carbon bond, and preferably exhibits a viscosity ranging
from 10 to 100,000 cs at room temperature, and in particular,
25.degree. C.
[0069] As the aforementioned aminoalkylsilicone oil, one in which G
is substituted by a formula:
--(NR.sup.4CH.sub.2CH.sub.2).sub.zNR.sup.4.sub.2 (wherein each
R.sup.4 independently the same as described above, and z is a
number of 0.ltoreq.z.ltoreq.4) in the aforementioned formula (4)
may be mentioned.
[0070] Interleaving paper obtained from the wood pulp of the
present invention, and in particular, glass plate-interleaving
paper of the present invention is used by being inserted between
glass plates. For example, the aforementioned glass
plate-interleaving paper is typically inserted between two glass
plates, and a plurality of glass plates with the glass
plate-interleaving paper inserted form a laminate as a whole. The
laminate mentioned above is to be stored and transported. In
addition, interleaving paper formed from the wood pulp of the
present invention, and in particular, the glass plate-interleaving
paper of the present invention may be used for packaging a single
glass plate or the laminate of glass plates mentioned above.
[0071] The glass plates are not particularly limited, but are
preferably glass plates for flat panel displays such as plasma
display panels, liquid crystal display panels (in particular, TFT
liquid crystal display panels), organic EL display panels and the
like. Microelectrodes, bulkheads and the like are formed on the
surface of the glass plates for flat panel displays. By using glass
plate-interleaving paper formed from wood pulp of the present
invention, and in particular, glass plate-interleaving paper of the
present invention, the transfer of silicone to glass plates can be
controlled or inhibited. For this reason, even if microelectrodes,
bulkheads and the like are formed on the surface of the glass
plates, problems caused by silicone can be controlled and
inhibited. As a result, defects of displays can be controlled and
inhibited.
[0072] In particular, in accordance with growing in size of
displays, the size and weight of the glass plates for flat panel
displays increase. The glass plate-interleaving paper formed from
the wood pulp of the present invention, and in particular, glass
plate-interleaving paper of the present invention can well protect
the surface of such glass plates with a large size and a large
weight. In particular, the glass plate-interleaving paper formed
from the wood pulp of the present invention, and in particular,
glass plate-interleaving paper of the present invention has an
extremely reduced amount of silicone. For this reason, even if
pressure is exerted on interleaving paper by glass plates with a
large weight, the transfer of silicone to glass plates can be
controlled and inhibited. Therefore, glass plate-interleaving paper
formed from the wood pulp of the present invention, and in
particular, glass plate-interleaving paper of the present invention
can be suitably used for glass plates for flat panel displays in
which cleanliness of the surface is particularly required.
EXAMPLES
[0073] Hereinafter, the present invention is described in detail
with reference to Examples and Comparative Examples. It should be
understood that the scope of the present invention is not limited
to these Examples.
[0074] (1) Quantitative Measurement of Silicone
[0075] Interleaving paper was cut into an about 1 cm square, and
subjected to soxhlet extraction with hexane for about 3.5 hours.
The obtained extract was concentrated by means of a rotary
evaporator. The residue was re-dissolved in 1 mL of deuterated
chloroform and subjected to a .sup.1H-NMR measurement. The
quantitative determination was carried out according to an absolute
calibration curve method using a deuterated chloroform solution of
a polydimethylsiloxane as a standard product for forming a
reference standard. As an NMR device, AVANCE 500 model
(manufactured by Bruker BioSpin Co., Ltd.) was used.
[0076] (2) Transfer Test to Glass (Transportation Test)
[0077] Urethane foam was placed on a glass mount face on an
L-shaped mount frame made of aluminum at an angle of 75 degrees.
120 glass plates, each glass plate having a size of 680
mm.times.880 mm.times.0.7 mm, and glass plate-interleaving paper
inserted between every glass plates were set against a back face
which vertically extends from a rear end part of a mount face for
vertically mounting glass plates, so that the glass plates were set
parallel to the back face. The glass plates were fixed thereon by
putting a strip-shaped belt which was fixed to the mount frame,
along the whole periphery from the rear end part to the back face.
The mount frame to which glass plates had been set as described
above was completely covered with a packaging material in order to
prevent contamination of dust and the like from the outside.
Subsequently, transportation test by a truck was carried out. The
test was carried out under the transportation conditions of 1,000
km of transportation distance (stored for 5 days under the
circumstance of 40.degree. C..times.95% RH during transportation).
Subsequently, the presence or absence of the silicone on the
surface of glass plates was confirmed by means of a FT-IR
analysis.
[0078] Manufacture of Wood Pulp
[0079] In an apparatus for manufacturing nadelholz bleached kraft
pulp, comprising a digesting process, a cleaning process, an oxygen
delignification reaction process, and a multistage bleaching
process with chlorine dioxide and hydrogen peroxide, an appropriate
amount of an undiluted solution of "Pronal A 5044" (manufactured by
TOHO Chemical Industry Co., Ltd.) of an inorganic oil-based
defoaming agent which was a non-silicone-based defoaming agent was
continuously added as a defoaming agent in a cleansing solution of
a drum washer immediately after knots were removed after the
digesting process. In addition, an appropriate amount of "Pronal A
5044", which was the same as described above, was added as a
defoamer to be added in a wash press in the press cleansing
process. As described above, nadelholz bleached kraft pulp A was
obtained using a non-silicone-based defoamer during the
manufacturing processes.
[0080] In addition, nadelholz bleached kraft pulp B was obtained in
the same manner as described above, with the exception of using "SN
defoamer 551K" (manufactured by SAN NOPCO Limited) which was a
silicone-based defoamer, as a defoamer.
Example 1
[0081] As wood pulp, nadelholz bleached kraft pulp A in an amount
of 100 parts by weight was prepared, and disaggregated to prepare a
slurry having a beating degree of 520 ml c.s.f. Polyacrylamide
(product name: Polystron 1250, manufactured by Arakawa Chemical
Industries Ltd.) was added as a paper strengthening agent in an
amount of 0.4 parts by mass with respect to the total pulp mass.
Thereby, a pulp slurry with a 0.4% concentration was prepared. The
obtained pulp slurry was subjected to paper making by means of a
Fourdrinier paper machine. Thereby, glass plate-interleaving paper
with a base weight of 50 g/m.sup.2 was obtained.
Example 2
[0082] Glass plate-interleaving paper having a base weight of 50
g/m.sup.2 was obtained in the same manner as that of Example 1,
with the exception of using a mixture of 80 parts by weight of
nadelholz bleached kraft pulp A and 20 parts by weight of nadelholz
bleached kraft pulp B as wood pulp.
Comparative Example 1
[0083] Glass plate-interleaving paper having a base weight of 50
g/m.sup.2 was obtained in the same manner as that of Example 1,
with the exception of using 100 parts by weight of nadelholz
bleached kraft pulp B as wood pulp.
[0084] The amount of silicone contained in the glass
plate-interleaving paper obtained in each of the Examples and
Comparative Example is shown in Table 1. The amount of silicone
contained in the glass plate-interleaving paper also indicates the
amount of silicone contained in the wood pulp used in the
manufacturing the aforementioned interleaving paper.
TABLE-US-00001 TABLE 1 Amount of silicone contained (ppm) Example 1
<0.01 Example 2 0.4 Comparative 2.0 Example 1
[0085] As a result of confirming the transfer of the glass
plate-interleaving paper obtained in each of the Examples and
Comparative Example to the glass plates in the transportation test,
on the surface of the glass plates using the interleaving paper of
Example 1, no silicone was detected at all. On the surface of the
glass plates using the interleaving paper of Example 2, a very
small amount of silicone was detected, but disconnection of color
film was not observed when an array formation of a liquid crystal
panel was carried out using the aforementioned glass plates. On the
other hand, on the surface of glass plates using the interleaving
paper of Comparative Example 1, silicone contamination was
confirmed. When an array formation of a liquid crystal panel was
carried out using the aforementioned glass plates, disconnection of
color film was observed.
[0086] From the aforementioned results, it can be seen that since
an amount of silicone contained in wood pulp of the present
invention is 0.5 ppm or less with respect to the absolute dry mass
of wood pulp of the present invention, glass plate-interleaving
paper of the present invention formed from the wood pulp of the
present invention also contains an amount of silicone is 0.5 ppm or
less, and therefore, the transfer of silicone to glass plates from
the aforementioned glass plate-interleaving paper can be prevented,
and as a result, glass plates with which an array formation of a
liquid crystal panel can be suitably carried out can be
manufactured.
* * * * *