U.S. patent application number 13/375965 was filed with the patent office on 2012-05-10 for method for producing inorganic particle composite body.
This patent application is currently assigned to SUMITOMO CHEMICAL COMPANY, LIMITED. Invention is credited to Makiko Hara, Makoto Nagata, Naoko Sakaya, Taiichi Sakaya.
Application Number | 20120114518 13/375965 |
Document ID | / |
Family ID | 43297845 |
Filed Date | 2012-05-10 |
United States Patent
Application |
20120114518 |
Kind Code |
A1 |
Hara; Makiko ; et
al. |
May 10, 2012 |
Method for Producing Inorganic Particle Composite Body
Abstract
A method for producing an inorganic particle composite body
formed of a mixture of a plastically deformable metal, and
inorganic particles that do not plastically deform under a
condition under which the metal plastically deforms, wherein the
method comprises: a step of preparing an inorganic particles
structural body that is formed of a mixture of the metal and the
inorganic particles and that contains a vacant space therein, and a
step of plastically deforming the metal in the structural body.
Inventors: |
Hara; Makiko; (Chiba,
JP) ; Nagata; Makoto; (Chiba, JP) ; Sakaya;
Taiichi; (Chiba, JP) ; Sakaya; Naoko; (Chiba,
JP) |
Assignee: |
SUMITOMO CHEMICAL COMPANY,
LIMITED
Chuo-ku, Tokyo
JP
|
Family ID: |
43297845 |
Appl. No.: |
13/375965 |
Filed: |
June 4, 2010 |
PCT Filed: |
June 4, 2010 |
PCT NO: |
PCT/JP2010/059895 |
371 Date: |
January 25, 2012 |
Current U.S.
Class: |
419/66 |
Current CPC
Class: |
C22C 1/1094 20130101;
B29C 70/606 20130101; B29C 70/64 20130101; B29K 2033/12 20130101;
Y10T 428/24942 20150115; B29K 2105/16 20130101; B29K 2023/12
20130101; B29K 2995/0087 20130101; C22C 32/001 20130101; B29K
2995/007 20130101; B05D 1/30 20130101; B29K 2509/00 20130101; B29K
2995/0024 20130101; C22C 29/12 20130101; C22C 1/1026 20130101; B29K
2067/003 20130101; B29K 2995/0093 20130101; B29C 43/003
20130101 |
Class at
Publication: |
419/66 |
International
Class: |
B22F 3/02 20060101
B22F003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 5, 2009 |
JP |
2009-135913 |
Aug 31, 2009 |
JP |
2009-199765 |
Aug 31, 2009 |
JP |
2009-199766 |
Aug 31, 2009 |
JP |
2009-199767 |
Aug 31, 2009 |
JP |
2009-199768 |
Aug 31, 2009 |
JP |
2009-199769 |
Aug 31, 2009 |
JP |
2009-199770 |
Aug 31, 2009 |
JP |
2009-199771 |
Aug 31, 2009 |
JP |
2009-199772 |
Claims
1. A method for producing an inorganic particle composite body
formed of a mixture of a plastically deformable metal, and
inorganic particles that do not plastically deform under a
condition under which the metal plastically deforms, wherein the
method comprises: a step of preparing an inorganic particles
structural body that is formed of a mixture of the metal and the
inorganic particles and that contains a vacant space therein, and a
step of plastically deforming the metal in the structural body.
2. The method according to claim 1, wherein the volume of the
inorganic particles is larger than the volume of the metal in the
inorganic particle structural body.
3. The method according to claim 1, wherein the step of plastically
deforming the metal is a step of plastically deforming the metal by
pressurizing the inorganic particle structural body.
4. The method according to claim 1, wherein the step of plastically
deforming the metal is a step of plastically deforming the metal by
applying an electromagnetic wave to the inorganic particle
structural body.
5. The method according to claim 1, wherein the method further
comprises a step of applying hydrophilization to the surface of the
structural body produced by carrying out the step of plastically
deforming the metal.
6. The method according to claim 1, wherein the method further
comprises a step that is a step of applying hydrophilization to the
surface of the inorganic particle structural body and that is
carried out before carrying out the step of plastically deforming
the metal.
7. The method according claim 1, wherein the method further
comprises a step of applying hydrophobization to the surface of the
structural body produced by carrying out the step of plastically
deforming the metal.
8. The method according to claim 1, wherein the method further
comprises a step that is a step of applying hydrophobization to the
surface of the inorganic particle structural body and that is
carried out before carrying out the step of plastically deforming
the metal.
9. The method according to claim 1, wherein the method further
comprises a step of applying antireflecting treatment to the
surface of the structural body produced by carrying out the step of
plastically deforming the metal.
10. The method according to claim 1, wherein the method further
comprises a step that is a step of applying antireflecting
treatment to the surface of the inorganic particle structural body
and that is carried out before carrying out the step of plastically
deforming the metal.
11. The method according to claim 1, wherein the method further
comprises a step of giving a glass layer to the surface of the
structural body produced by carrying out the step of plastically
deforming the metal.
12. The method according to claim 1, wherein the method further
comprises a step is that is a step of giving a glass layer to the
surface of the inorganic particle structural body and that is
carried out before carrying out the step of plastically deforming
the metal.
Description
TECHNICAL FIELD
[0001] The present invention relates to a method for producing an
inorganic particle composite body made of metal and inorganic
particles.
BACKGROUND ART
[0002] Front panels of flat panel displays, displays of portable
instruments such as cellular phones, and the like have been
provided with treatment to increase surface hardness for the
purpose of prevention of scratching, more specifically, treatment
to form a hardcoat layer. Conventionally known technologies to form
a hardcoat layer on a substrate includes a method comprising
applying a mixture of inorganic particles, an ultraviolet-curable
resin, and so on to a substrate and then ultraviolet curing it, and
a method comprising laminating a coating material made of only a
silica precursor or a mixture of a silica precursor and inorganic
particles on a substrate and the curing the coating material by the
sol-gel method (see JP 2008-150484 A and JP 2007-529588 T). In the
above-described conventional technologies, however, since a
hardcoat layer containing inorganic particles is different from a
substrate in properties (e.g., modulus of elasticity and
coefficient of linear expansion) , the higher the surface hardness
of a hardcoat layer is made, the more liable to peel off the
hardcoat layer is.
When a film made of only a hardcoat layer is formed by removing a
substrate, the harder the film is, the more brittle it is. In
addition, surface hardness decreases as the brittleness of a film
is reduced.
DISCLOSURE OF THE INVENTION
[0003] An object of the present invention is to provide an
inorganic particle composite body having reduced brittleness or
reduced ease in peeling while having surface hardness derived from
inorganic particles. The present invention provides the following
[1] through [12] .
[0004] [1] A method for producing an inorganic particle composite
body formed of a mixture of a plastically deformable metal, and
inorganic particles that do not plastically deform under a
condition under which the metal plastically deforms, wherein the
method comprises: a step of preparing an inorganic particles
structural body that is formed of a mixture of the metal and the
inorganic particles and that contains a vacant space therein, and a
step of plastically deforming the metal in the structural body.
[0005] [2] The method according to [1] , wherein the volume of the
inorganic particles is larger than the volume of the metal in the
inorganic particle structural body.
[0006] [3] The method according to [1] or [2], wherein the step of
plastically deforming the metal is a step of plastically deforming
the metal by pressurizing the inorganic particle structural
body.
[0007] [4] The method according to [1] or [2], wherein the step of
plastically deforming the metal is a step of plastically deforming
the metal by applying an electromagnetic wave to the inorganic
particle structural body.
[0008] [5] The method according to any one of [1] to [4], wherein
the method further comprises a step of applying hydrophilization to
the surface of the structural body produced by carrying out the
step of plastically deforming the metal.
[0009] [6] The method according to any one of [1] to [4], wherein
the method further comprises a step that is a step of applying
hydrophilization to the surface of the inorganic particle
structural body and that is carried out before carrying out the
step of plastically deforming the metal.
[0010] [7] The method according to any one of [1] to [4], wherein
the method further comprises a step of applying hydrophobization to
the surface of the structural body produced by carrying out the
step of plastically deforming the metal.
[0011] [8] The method according to any one of [1] to [4], wherein
the method further comprises a step that is a step of applying
hydrophobization to the surface of the inorganic particle
structural body and that is carried out before carrying out the
step of plastically deforming the metal.
[0012] [9] The method according to any one of [1] to [4], wherein
the method further comprises a step of applying antireflecting
treatment to the surface of the structural body produced by
carrying out the step of plastically deforming the metal.
[0013] [10] The method according to any one of [1] to [4], wherein
the method further comprises a step that is a step of applying
antireflecting treatment to the surface of the inorganic particle
structural body and that is carried out before carrying out the
step of plastically deforming the metal.
[0014] [11] The method according to any one of [1] to [4], wherein
the method further comprises a step of giving a glass layer to the
surface of the structural body produced by carrying out the step of
plastically deforming the metal.
[0015] [12] The method according to any one of [1] to [4], wherein
the method further comprises a step is that is a step of giving a
glass layer to the surface of the inorganic particle structural
body and that is carried out before carrying out the step of
plastically deforming the metal.
[0016] According to the method of the present invention, it is
possible to obtain an inorganic particle composite body having
reduced brittleness or reduced ease in peeling while having surface
hardness derived from inorganic particles.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a schematic diagram of an inorganic particle
structural body 3a.
[0018] FIG. 2 is a schematic diagram of an inorganic particle
composite body 4a obtained by pressurizing the inorganic particle
structural body 3a.
[0019] FIG. 3 is a schematic diagram of an inorganic particle
structural body 3b.
[0020] FIG. 4 is a schematic diagram of an inorganic particle
composite body 4b obtained by pressurizing the inorganic particle
structural body 3b.
[0021] FIG. 5 is a schematic diagram of an inorganic particle
structural body 3c.
[0022] FIG. 6 is a schematic diagram of an inorganic particle
composite body 4c obtained by pressurizing the inorganic particle
structural body 3c.
[0023] FIG. 7 is a schematic diagram of an inorganic particle
structural body 3d.
[0024] FIG. 8 is a schematic diagram of inorganic particle
composite body 4d obtained by pressurizing the inorganic particle
structural body 3d.
[0025] FIG. 9 is a schematic diagram of an inorganic particle
structural body 3e.
[0026] FIG. 10 is a schematic diagram of an inorganic particle
composite body 4e obtained by pressurizing the inorganic particle
structural body 3e.
[0027] FIG. 11 is a schematic diagram of a hydrophilic inorganic
particle composite body 5a obtained by applying hydrophilization to
the surface of the composite body 4a illustrated in FIG. 2.
[0028] FIG. 12 is a schematic diagram of a hydrophilic inorganic
particle composite body 5b obtained by applying hydrophilization to
the surface of the composite body 4b illustrated in FIG. 4.
[0029] FIG. 13 is a schematic diagram of a hydrophobic inorganic
particle composite body 7a obtained by applying hydrophobization to
the surface of the composite body 4a illustrated in FIG. 2.
[0030] FIG. 14 is a schematic diagram of a hydrophobic inorganic
particle composite body 7b obtained by applying hydrophobization to
the surface of the composite body 4b illustrated in FIG. 4.
[0031] FIG. 15 is a schematic diagram of an antireflective
inorganic particle composite body 7a obtained by applying
antireflecting treatment to the surface of the composite body 4a
illustrated in FIG. 2.
[0032] FIG. 16 is a schematic diagram of an antireflective
inorganic particle composite body 7b obtained by applying
antireflecting treatment to the surface of the composite body 4b
illustrated in FIG. 4.
[0033] FIG. 17 is a schematic diagram of an inorganic particle
composite body 11a obtained by giving a glass layer to the surface
of the composite body 4a illustrated in FIG. 2.
[0034] FIG. 18 is a schematic diagram of an inorganic particle
composite body 11b obtained by giving a glass layer to the surface
of the composite body 4b illustrated in FIG. 4.
[0035] FIG. 19 is a schematic diagram of the inorganic particle
structural body 3a.
[0036] FIG. 20 is schematic diagram 4a of an inorganic particle
composite molded article obtained by molding the inorganic particle
structural body 3a.
[0037] FIG. 21 is a schematic diagram of the inorganic particle
structural body 3b.
[0038] FIG. 22 is schematic diagram 4b of an inorganic particle
composite molded article obtained by molding the inorganic particle
structural body 3b.
[0039] FIG. 23 is a schematic diagram of the process for molding
(press molding) the composite body 4a illustrated in FIG. 2.
[0040] FIG. 24 is a schematic diagram concerning a method of
determining a volume fraction V (%) of the metal with which an
inorganic particle layer has been filled.
[0041] FIG. 25 is a TEM photograph of a cross section of the
inorganic particle composite body produced in Example 1.
[0042] FIG. 26 is a TEM photograph of a cross section of the
inorganic particle composite body produced in Comparative Example
1.
[0043] FIG. 27 is a TEM photograph of a cross section of the
inorganic particle composite body produced in Example 2.
[0044] In the drawings, 1, 1a, 1b, 1c, 1d: inorganic particle; 2:
metal; 3a, 3b, 3c, 3d, 3e : inorganic particle structural body; 4a,
4b, 4c, 4d, 4e : inorganic particle composite body; 5a, 5b:
hydrophilic inorganic particle composite body; 6: hydrophilized
layer; 7a, 7b: hydrophobic inorganic particle composite body; 8:
hydrophobized layer; 9a, 9b: antireflective inorganic particle
composite body; 10: antireflection treatment layer; 11a, 11b:
inorganic particle composite body with a glass layer; 12: glass
layer; 13: pressing mold; 14: inorganic particle existing
region.
Mode for Carrying Out the Invention
[0045] In one aspect the present invention is a method for
producing an inorganic particle composite body formed of a mixture
of a plastically deformable metal, and inorganic particles that do
not plastically deform under a condition under which the metal
plastically deforms, wherein the method comprises: a step of
preparing an inorganic particles structural body that is formed of
a mixture of the metal and the inorganic particles and that
contains a vacant space therein, and a step of plastically
deforming the metal in the structural body.
[0046] The metal contained in the inorganic particle structural
body is not particularly restricted if it is a metal capable of
being plastically deformed, in other words, if it has plasticity.
The plasticity as referred to herein is a property to deform
continuously with generation of permanent strain when a stress has
exceeded the limit of elasticity. That a metal plastically deforms
means that a stress exceeding the limit of elasticity is applied to
a metal and, as a result, a permanent strain is produced, so that
the metal is deformed and the metal is brought into a state that
the deformed condition is maintained even if the stress is removed.
Examples of such a metal include metals such as platinum, gold,
palladium, silver, copper, nickel, zinc, aluminum, iron, cobalt,
rhodium, ruthenium, tin, lead, bismuth, tungsten, and indium,
alloys and solders composed of two or more metals. The metal may be
in any shape, e.g., a particulate shape, a tabular shape, and a
fibrous shape. As to the metal, a single kind of metal may be used,
or two or more kinds of metals may be used in combination.
[0047] When the metal is in a particulate shape, the particle
diameter thereof can be measured in the same way used in the
particle diameter measurement of inorganic particles described
later. Although the particle diameter of metal particles is not
limited, the particle diameter is from 1 to 500 nm, preferably from
1 to 200 nm, and more preferably from 2 to 100 nm when the aspect
ratio is 2 or less.
[0048] Examples of the inorganic particles contained in an
inorganic particle structural body include: metal oxides, such as
iron oxide, magnesium oxide, aluminum oxide, silicon oxide (silica)
, titanium oxide, cobalt oxide, copper oxide, zinc oxide, cerium
oxide, yttrium oxide, indium oxide, silver oxide, tin oxide,
holmium oxide, bismuth oxide, and indium tin oxide; metal complex
oxides such as indium tin oxide; metal salts such as calcium
carbonate and barium sulfate; and inorganic layered compounds such
as clay minerals and carbon-based intercalation compounds.
Inorganic particles do not include metal particles.
[0049] As an inorganic layered compound, an inorganic layered
compound having a property that it is swollen and cleaved by a
solvent is used preferably from a viewpoint that a large aspect
ratio can be used easily. As such an inorganic layered compound
having a property that it is swollen and cleaved by a solvent, a
clay mineral that exhibits swellability and cleavability in a
solvent is used particularly preferably. Clay minerals are
generally classified into a type having a two-layer structure
having, on a silica tetrahedral layer, an octahedral layer
containing aluminum, magnesium or the like as a central metal, and
a type having a three-layer structure in which an octahedral layer
containing aluminum, magnesium or the like as a central metal is
sandwiched on its both sides by silica tetrahedral layers. Examples
of the former type include kaolinite series, antigorite series, and
so on, whereas examples of the latter type include smectite series,
vermiculite series, mica series, and so on depending on the number
of interlayer cations. Clay minerals are minerals containing
silicate minerals having a layered crystal structure as their
primary ingredients. Examples thereof include kaolinite series,
antigorite series, smectite series, vermiculite series, and mica
series. Specific examples include kaolinite, dickite, nacrite,
halloysite, antigorite, chrysotile, pyrophyllite, montmorillonite,
hectorite, tetrasilylic mica, sodium taeniolite, muscovite,
margarite, talc, vermiculite, phlogopite, xanthophyllite, and
chlorite. As to the inorganic particle, only a single kind of
inorganic particles may be used, or two or more kinds of inorganic
particles may be used in combination. It is also possible to form
an inorganic particle structural body by combining particles
differing in average particle diameter.
[0050] When inorganic particles constituting an inorganic particle
layer are hydrophilic, since the inorganic particle composite body
has a portion with superior hydrophilicity, it has antifouling
property (self-cleaning property), by which dirt can be removed by
water, and property of difficult attachment or easy detachment of
snow or ice (prevention of snow/ice attachment) in addition to
property to prevent surface scratching, it is suited as building
components such as a roof of a dome stadium, a roof of a stadium, a
roof of a carport, roofs of other types of buildings, an awning, a
wall of a building, a window, a traffic display, and acoustical
insulation boards for roads or buildings; agricultural components
such as a film for agricultural houses, a film for tunnels, a film
for curtains, a mulch film, a sprinkling hose, sprinkling
materials, and a seed and seedling box; components of instruments
for transportation such as skirt parts, exterior boards, and
windows of trains and exterior boards, windows, bumpers, and
mirrors of cars; furniture members such as mirrors, floorings,
table tops, chairs, and sofas; household appliances such as
television, personal computers, washing machines, and
refrigerators; electric members such as electric wires, cables,
antennas, steel towers for electric wires and cables, and lighting
surfaces of solar cells.
[0051] Moreover, taking advantage of antistatic property that a
hydrophilic particles film easily exerts, it is suitable also as
antistatic members, such as an antistatic film, a film for
packaging, a film for removing electricity, a material for
packaging electronic components, and a material for food packaging.
Examples of hydrophilic inorganic particles include particles of
metal oxides. Inorganic particles to which hydrophilization has
been applied can also be used.
[0052] The shape of inorganic particles may be any shape, such as
spherical shape, needle-like shape, scaly shape, and fibrous shape.
In the present invention, the particle diameter of such particles
refers to an average particle diameter measured by the dynamic
light scattering method, the Sears method, or the laser diffraction
scattering method or a spherical equivalent diameter calculated
from a BET specific surface area. In the case of a fibrous shape,
it means a diameter of a section thereof . The Sears method, which
is disclosed in Analytical Chemistry, Vol. 28, p. 1981-1983, 1956,
is an analytical method to be applied to the measurement of the
average particle diameter of silica particles; it is a method in
which the surface area of silica particles is determined from the
amount of NaOH to be consumed for making a colloidal silica
dispersion liquid from pH=3 to pH=9 and then a sphere equivalent
diameter is calculated from the determined surface area. When
inorganic particles have an aspect ratio of up to 2, the average
particle diameter thereof can be determined also from an image
observed using an optical microscope, a laser microscope, a
scanning electron microscope, a transmission electron microscope,
an atomic force microscope, or the like. The particle diameter of
inorganic particles is preferably from 1 to 10000 nm from the
viewpoint of interaction force between particles, such as atomic
force and van der Waals force. When the inorganic particles have an
aspect ratio of 2 or less, the particle diameter is from 1 to 500
nm, preferably from 1 to 200 nm, and more preferably from 2 to 100
nm. When the inorganic particles are an inorganic layered compound,
the particle diameter is from 10 to 3000 nm, preferably from 20 to
2000 nm, and more preferably from 100 to 1000 nm.
[0053] While inorganic particles that do not plastically deform
under conditions under which metal plastically deforms are used in
the method of the present invention, the fact that inorganic
particles that do not plastically deform under conditions under
which metal plastically deforms can be confirmed by heating or
pressurizing the inorganic particles under operation conditions
under which metal plastically deforms and checking the change in
shape or property of the inorganic particles.
[0054] In the case that the inorganic particle structural body is
formed from a mixture of inorganic particles and metal particles,
the mixing ratio of both particles is arbitrary, but from the
viewpoint of keeping surface hardness, it is preferred that the
volume fraction of the inorganic particles in the inorganic
particle structural body be larger than the volume fraction of the
metal particles.
[0055] In the present invention, a substrate refers to a material
that supports an inorganic particle structural body. The substrate
is not particularly restricted if it can support metal or an
inorganic particle structural body. Specifically, metal, resin,
glass, ceramics, paper, cloth, and the like are used in a form
(tabular form such as film form and sheet form, rod form, fibrous
form, spherical form, three-dimensional structural form, etc.), if
necessary.
[0056] The inorganic particle structural body to be used in the
present invention is a structural body that has vacant spaces in at
least a part thereof, and representative examples of the structure
thereof are shown in FIG. 1 and FIG. 3. As illustrated in these
drawings, the inorganic particle structural body suitable for the
present invention usually has a porous structure, and it is
preferred that at least some of the pores interconnect. The
interconnection of pores in a structural body allows vacant spaces
in the structural body to be filled easily with metal plastically
deformed by pressuring the structural body.
[0057] Methods for producing an inorganic particle structural body
include the following, for example.
[0058] Method 1: a method that comprises applying a coating liquid
containing inorganic particles, particulate metal, and a liquid
dispersion medium to a substrate, and then removing the liquid
dispersion medium from the applied coating liquid (in other words,
drying the coating liquid) to form an inorganic particle structural
body.
[0059] FIG. 1 is a schematic diagram of an inorganic particle
structural body 3a formed by the above-described Method 1 (a
substrate is omitted). This example is a case that the shape of
inorganic particles is a sphere. An inorganic particle structural
body formed of spherical inorganic particles and metal particles
has vacant spaces between the particles. By pressurizing the
structural body 3a, the metal part in the structural body 3a
plastically deforms and fills the vacant spaces in the structural
body 3a gradually. It is conceivable that an inorganic particle
composite body produced by the method of the present invention is
formed as a result of moving the plastically deformed metal to at
least some of the vacant spaces in the structural body 3a and
filling them. An inorganic particle composite body in the case of
having filled up all vacant spaces with metal is the composite body
4a illustrated in FIG. 2.
[0060] In the method of the present invention, by plastically
deforming metal existing in a structural body, the plastically
deformed metal is filled into vacant spaces in the structural body.
In some cases, however, some vacant spaces among many vacant spaces
in the structural body are filled up with metal but the other
remain unfilled with metal, or in some cases a vacant space is
partially filled with metal. Of course, all vacant spaces may be
completely filled up with metal. The degree of plastic deformation
of metal or filling of metal into vacant spaces varies depending
upon the intended function of an inorganic particle composite
body.
[0061] FIG. 3 is a schematic diagram of an inorganic particle
structural body 3b formed by the above-described Method 1. This
example is a case that the shape of inorganic particles is
plate-like. The structural body formed of plate-like inorganic
particles and metal particles has vacant spaces between these
particles. By pressurizing the structural body 3b, the metal part
in the structural body 3b plastically deforms and fills the vacant
spaces in the structural body 3b gradually. It is conceivable that
an inorganic particle composite body produced by the method of the
present invention is formed as a result of moving the plastically
deformed metal to at least some of the vacant spaces in the
structural body 3b and filling them. An inorganic particle
composite body in the case of having filled up all vacant spaces
with metal is the composite body 4b illustrated in FIG. 4.
[0062] FIG. 5 is a schematic diagram of a stacked structure body 3c
produced by forming an inorganic particle structural body by the
above-described Method 1, then plastically deforming the metal
contained in the structural body to form a hybridized inorganic
particle structural body, and subsequently further forming thereon
a layer made of a mixture of metal and inorganic particles. This
example shows the case that inorganic particles are spherical and
metal is in the form of spherical particles. The stacked structural
body 3c formed of spherical inorganic particles and spherical metal
particles has vacant spaces between these particles.
[0063] First, an inorganic particle structural body made of
inorganic particles and metal particles by the above-described
Method 1 using a mixture of the inorganic particles and the metal
particles. This inorganic particle structural body is hereinafter
referred to as an "initial inorganic particle structural body."
Subsequently, the metal particles in the initial inorganic particle
structural body are plastically deformed and thereby the inorganic
particles in the initial structural body are rearranged to pack in
a higher density, so that the volume of the vacant spaces in the
structural body decreases. The resulting structural body is called
a "hybridized inorganic particle structural body." Next, on the
hybridized inorganic particle structural body is formed a layer
made of a mixture of metal particles and inorganic particles
differing in composition from the above-described mixture used for
the preparation of the initial inorganic particle structural body.
Consequently, a stacked structure body 3c comprising the hybridized
inorganic particle structural body and a newly formed layer is
formed. The aforementioned layer newly formed also contains vacant
spaces because it is made of particles. Next, the metal in the
stacked structural body, that is, the metal particles in the
aforementioned newly formed layer and the plastically deformed
metal and the remaining metal particles in the hybridized inorganic
particle structural body, is plastically deformed. As a
consequence, the inorganic particles in the stacked structural body
are rearranged and packed in a higher density. The volume of vacant
spaces of the stacked structural body decreases. Thus, an inorganic
particle composite body 4c illustrated in FIG. 6 is formed.
[0064] FIG. 7 illustrates a stacked structural body produced using
plate-like inorganic particles; the stacked structural body is
basically the same of the stacked structural body illustrated in
FIG. 5 except that the inorganic particles contained are not
spherical but plate-like. Using the stacked structural body
illustrated in FIG. 7, the metal contained therein, that is, the
metal already plastically deformed and the remaining metal
particles in the hybridized inorganic particle structural body and
the metal particles contained in the layer formed on the hybridized
inorganic particle structural body, is plastically deformed. As a
result, inorganic particles in the stacked structural body are
rearranged and packed in a higher density. Thus, the volume of
vacant spaces in the stacked structural body 4d decreases, so that
an inorganic particle composite body illustrated in FIG. 8 is
formed.
[0065] FIG. 9 is a schematic diagram of another stacked structural
body 3e. This stacked structural body 3e is formed by performing
the operations described below: an inorganic particle structural
body is formed by the above-described Method 1;
subsequently, the metal contained in the inorganic particle
structural body is plastically deformed to form a hybridized
inorganic particle structural body; then, a layer made of a mixture
of metal and inorganic particles is further formed on the
hybridized inorganic particle structural body to form a first
stacked structural body; next, a layer made of a mixture of metal
and inorganic particles is further formed on the first stacked
structural body to form a second stacked structural body;
subsequently, a layer made of a mixture of metal and inorganic
particles is further formed on the first stacked structural body to
form a third stacked structural body; next, the metal contained in
the third stacked structural body is plastically deformed and
thereby the inorganic particles contained in the stacked structural
body are rearranged to pack in a higher density. This example shows
the case that inorganic particles are spherical and metal is in the
form of spherical particles. The stacked structural body 3e formed
of spherical inorganic particles and spherical metal particles has
vacant spaces between these particles.
[0066] First, an inorganic particle structural body made of
inorganic particles and metal particles by the above-described
Method 1 using a mixture of inorganic particles and metal
particles. This inorganic particle structural body is hereinafter
referred to as an "initial inorganic particle structural body."
Subsequently, the metal particles in the initial inorganic particle
structural body are plastically deformed and thereby the inorganic
particles in the initial structural body are rearranged to pack in
a higher density, so that the volume of the vacant spaces in the
structural body decreases. The resulting structural body is called
a "hybridized inorganic particle structural body." Next, on the
hybridized inorganic particle structural body is formed a layer
made of a mixture of metal particles and inorganic particles
differing in composition from the above-described mixture used for
the preparation of the initial inorganic particle structural body.
Consequently, a stacked structure body 3c composed of the
hybridized inorganic particle structural body and a newly formed
layer is formed. Moreover, a layer made of a mixture of metal
particles and inorganic particles is stacked in the similar way.
These newly formed layers also contain vacant spaces because they
are made of particles. Next, the metal in the stacked structural
body, that is, the metal particles in the aforementioned newly
formed layer and the plastically deformed metal and the remaining
metal particles in the hybridized inorganic particle structural
body, is plastically deformed. As a consequence, the inorganic
particles in the stacked structural body are rearranged and packed
in a higher density. The volume of vacant spaces of the stacked
structural body decreases. Thus, an inorganic particle composite
body 4e illustrated in FIG. 10 is formed.
[0067] The inorganic particle composite body illustrated in FIG. 10
has four inorganic particle layers and the voidages of the
inorganic particle layers become smaller stepwise from the part
derived from the inorganic particle structural body formed first
(hereinafter referred to as "initial inorganic particle
layer-derived part") toward the part derived from the layer formed
last (hereinafter referred to as "last inorganic particle
layer-derived part"). The last inorganic particle layer-derived
part has almost no vacant spaces. An inorganic particle composite
body can be produced by stacking a plurality of inorganic particle
layers so that the voidage may vary stepwise to produce a stacked
inorganic particle structural body and then plastically deforming
the metal contained in the stacked inorganic particle structural
body. The voidage of an inorganic particle layer can be adjusted by
changing the particle diameter of the inorganic particles that
constitute the layer. By filling up from the initial inorganic
particle layer-derived part to the last inorganic particle
layer-derived part with metal, the inorganic particle composite
body 4e of FIG. 10 is formed. The resulting inorganic particle
composite body has both a region where the property of the metal is
dominant and a region where the property of the inorganic particles
is dominant. If the combination of inorganic particles and metal is
optimized, completely different properties can be given to one
inorganic particle composite body.
[0068] Now, consideration is made to the initial inorganic particle
layer-derived part, which has the highest voidage, and the last
inorganic particle layer-derived part, which has the lowest
voidage. When all the vacant spaces of a portion derived from the
initial inorganic particle layer, which is highest in voidage, have
been filled up with metal, the presence ratio of the metal to the
inorganic particles in this layer is high, so that this layer has a
property that is a combination of the property of the inorganic
particles and the property of the metal.
[0069] On the other hand, when the metal has been filled in the
vacant spaces of a portion derived from the last inorganic particle
layer, which is lowest in voidage, this layer has a property the
same as that of the inorganic particles because the presence ratio
of the metal to the inorganic particles in this layer is very low
and therefore this layer is hardly influenced by the property of
the metal.
[0070] Usually, if substances differing in property have been
united, adhesiveness will become poor because of the difference in
properties between the substances. For example, a laminate of glass
and a resin film easily delaminates because the coefficient of
linear expansion of an interface between glass and resin is
different. However, as illustrated in FIG. 10, in an inorganic
particle composite body in which the voidage is varied stepwise and
thereby properties of respective layers are varied stepwise,
adhesiveness between layers is high since a property varies
gradually within the composite body. As a result, completely
different properties can be imparted to an inorganic particle
composite body while keeping the adhesiveness between layers good.
It is preferred to fill at least some of the vacant spaces of the
stacked inorganic particle layer by plastically deforming the
metal.
[0071] FIG. 11 is a schematic diagram of a hydrophilic inorganic
particle composite body 5a obtained by applying hydrophilization to
the surface of a structural body obtained by performing a step of
plastically deforming metal (this corresponds to the inorganic
particle composite body 4a illustrated in FIG. 2). Preferred
methods of hydrophilization include a method comprising stacking a
layer containing a hydrophilizing agent onto at least a part of the
surface of a structural body and/or a method comprising reacting a
hydrophilizing agent to at least a part of the surface of a
structural body.
[0072] FIG. 12 is a schematic diagram of a hydrophilic inorganic
particle composite body 5b obtained by applying hydrophilization to
the surface of a structural body obtained by performing a step of
plastically deforming metal (this corresponds to the inorganic
particle composite body 4b illustrated in FIG. 4). Preferred
methods of hydrophilization include a method comprising stacking a
layer containing a hydrophilizing agent onto at least a part of the
surface of a structural body and/or a method comprising reacting a
hydrophilizing agent to at least a part of the surface of a
structural body.
[0073] FIG. 13 is a schematic diagram of a hydrophobic inorganic
particle composite body 7a obtained by applying hydrophobization to
the surface of a structural body obtained by performing a step of
plastically deforming metal (this corresponds to the inorganic
particle composite body 4a illustrated in FIG. 2). Preferred
methods of hydrophobization include a method comprising stacking a
layer containing a hydrophobizing agent onto at least a part of the
surface of a structural body and/or a method comprising reacting a
hydrophobizing agent to at least apart of the surface of a
structural body.
[0074] FIG. 14 is a schematic diagram of a hydrophobic inorganic
particle composite body 7b obtained by applying hydrophobization to
the surface of a structural body obtained by performing a step of
plastically deforming metal (this corresponds to the inorganic
particle composite body 4b illustrated in FIG. 4). Preferred
methods of hydrophobization include a method comprising stacking a
layer containing a hydrophobizing agent onto at least a part of the
surface of a structural body and/or a method comprising reacting a
hydrophobizing agent to at least a part of the surface of a
structural body.
[0075] FIG. 15 is a schematic diagram of an antireflective
inorganic particle composite body 9a obtained by applying
antireflecting treatment to the surface of a structural body
obtained by performing a step of plastically deforming metal (this
corresponds to the inorganic particle composite body 4a illustrated
in FIG. 2). A preferred method of antireflection treatment is a
method comprising providing an antireflecting agent to the surface
of a structural body by wet coating and/or dry coating (i.e., vapor
deposition).
[0076] FIG. 16 is a schematic diagram of an antireflective
inorganic particle composite body 9b obtained by applying
antireflecting treatment to the surface of a structural body
obtained by performing a step of plastically deforming metal (this
corresponds to the inorganic particle composite body 4b illustrated
in FIG. 4). A preferred method of antireflection treatment is a
method comprising providing an antireflecting agent to the surface
of a structural body by wet coating and/or dry coating (i.e., vapor
deposition).
[0077] FIG. 17 is a schematic diagram of a glass-coated inorganic
particle composite body 11a obtained by giving a glass layer to the
surface of a structural body obtained by performing a step of
plastically deforming metal (this corresponds to the inorganic
particle composite body 4a illustrated in FIG. 2). Preferred
methods of giving a glass layer include a method comprising bonding
a glass sheet and a structural body together via an adhesive, a
method comprising coating the surface of a structural body with a
glass precursor and then converting the glass precursor into glass,
and a method comprising extrusion-laminating molten glass to a
structural body.
[0078] FIG. 18 is a schematic diagram of a glass-coated inorganic
particle composite body 11b obtained by giving a glass layer to the
surface of a structural body obtained by performing a step of
plastically deforming metal (this corresponds to the inorganic
particle composite body 4b illustrated in FIG. 4). Preferred
methods of providing a glass layer include a method comprising
bonding a glass sheet and a structural body together via an
adhesive, a method comprising coating the surface of a structural
body with a glass precursor and then converting the glass precursor
into glass, and a method comprising extrusion-laminating molten
glass to a structural body.
[0079] FIG. 19 is a schematic diagram of an inorganic particle
structural body 3a formed by the above-described Method 1. By
forming the structural body 3a, a metal portion in the structural
body 3a deforms plastically and this gradually fills vacant spaces
in the structural body 3a and, simultaneously, the
three-dimensional shape of the surface of a molding machine in
contact with the structural body is transferred to the surface of
the structural body, so that the three-dimensional shape is given
to the surface of the structural body. When all vacant spaces have
been filled up, an inorganic particle composite molded article 4a
of FIG. 20 is formed. To leave some vacant spaces unfilled is
preferred because it is easy to perform painting treatment or the
like later.
[0080] FIG. 21 is a schematic diagram of an inorganic particle
structural body 3b formed by the above-described Method 1. By
forming the structural body 3b, a metal portion in the structural
body 3b deforms plastically and this gradually fills vacant spaces
in the structural body 3b and, simultaneously, the
three-dimensional shape of the surface of a molding machine in
contact with the structural body is transferred to the surface of
the structural body, so that the three-dimensional shape is given
to the surface of the structural body. When all vacant spaces have
been filled up, an inorganic particle composite molded article 4b
of FIG. 22 is formed. To leave some vacant spaces unfilled is
preferred because it is easy to perform painting treatment or the
like later.
[0081] FIG. 23 is a schematic diagram of the process (press
molding) for producing the composite body 4a illustrated in FIG. 2.
It is also permitted to preheat the inorganic particle structural
body before press molding or to heat or cool it in a mold during
press molding.
[0082] In the practice of the above-described Method 1, a coating
liquid containing inorganic particles, a particulate metal, and a
liquid dispersion medium is prepared., Although the liquid
dispersion medium may be any one having a function to disperse
particles and water and volatile organic solvents can be used,
water is preferred because it is easy to handle. In order to
improve the dispersibility to the solvent, it is permitted to apply
surface treatment to particles and also permitted to add a
dispersion medium electrolyte, a dispersion aid, and the like. When
dispersing particles colloidally in a coating liquid, it is
permitted to perform pH adjustment or add an electrolyte or a
dispersing agent, if necessary. In order to disperse particles
uniformly, it is permitted to use techniques, such as stirring with
a stirrer, ultrasonic dispersion, and super high pressure
dispersion (super high pressure homogenizer), if necessary.
Although the particle concentration of a coating liquid is not
particularly limited, it is preferably from 1 to 50% by weight for
maintaining the stability of the particles in the solution. When
the inorganic particles are made of alumina and the coating liquid
is in a colloidal state, it is preferred to add an anion, such as
chloride ion, sulfate ion, and acetate ion, to the coating liquid.
When the inorganic particles are made of silica and the coating
liquid is in a colloidal state, it is preferred to add a cation,
such as ammonium ion, alkali metal ion, and alkaline earth metal
ion, to the coating liquid. To the coating liquid may be added
additives, such as surfactant, polyhydric alcohols, soluble resins,
dispersibility resins, and organic electrolytes, for the purpose of
stabilizing the dispersion of particles.
[0083] When the coating liquid contains a surfactant, the content
thereof is usually 0.1 parts by weight or less based on 100 parts
by weight of the liquid dispersion medium. The surfactant to be
used is not particularly restricted and examples thereof include
anionic surfactants, cationic surfactants, nonionic surfactants,
and ampholytic surfactants. Examples of the anionic surfactants
include alkali metal salts of carboxylic acids and specifically
include sodium caprylate, potassium caprylate, sodium decanoate ,
sodium caproate, sodium myristate, potassium oleate,
tetramethylammonium stearate, and sodium stearate. Especially,
alkali metal salts of carboxylic acids with alkyl chains having
from 6 to 24 carbon atoms are preferred. Examples of the cationic
surfactants include cetyltrimethylammonium chloride,
dioctadecyldimethylammonium chloride, N-octadecylpyridinium
bromide, and cetyltriethylphosphonium bromide. Examples of the
nonionic surfactants include sorbitan esters of fatty acids and
glycerol esters of fatty acids. Examples of the ampholytic
surfactants include
2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, lauric
acid amidopropyl betaine, and the like.
[0084] When the coating liquid contains a polyhydric alcohol, the
content thereof is preferably 10 parts by weight or less, more
preferably 5 parts by weight or less based on 100 parts by weight
of the liquid dispersion medium. Addition of a small amount of a
polyhydric alcohol can improve the antistatic property of an
inorganic particle composite body. The polyhydric alcohol to be
used is not particularly restricted, and examples thereof include
glycol type polyhydric alcohols, such as ethylene glycol,
diethylene glycol, polyethylene glycol, propylene glycol,
dipropylene glycol, and polypropylene glycol, glycerol type
polyhydric alcohols, such as glycerol, diglycerol, and
polyglycerol, and methylol type polyhydric alcohols, such as
pentaerythritol, dipentaerythritol, and tetramethylolpropane.
[0085] When the coating liquid contains a soluble resin, the
content thereof is preferably 1 part by weight or less, more
preferably 0.1 parts by weight or less based on 100 parts by weight
of the liquid dispersion medium. Addition of a small amount of a
soluble resin can make the formation of an inorganic particle
structural body easier and can impart a function of the soluble
resin. The soluble resin to be used here is not particularly
restricted if it is soluble in the liquid dispersion medium, and
example thereof include polyvinyl alcohol type resins, such as
polyvinyl alcohol, ethylene-vinyl alcohol copolymers, and
copolymers containing vinyl alcohol units, and polysaccharides,
such as cellulose, methylcellulose, hydroxymethylcellulose, and
carboxymethylcellulose.
[0086] When the coating liquid contains a resin dispersable in a
solution, the content thereof is usually 10 parts by weight or
less, preferably 5 parts by weight or less based on 100 parts by
weight of the liquid dispersion medium. Addition of a small amount
of a dispersable resin can make the formation of an inorganic
particle structural body easier and can impart a function of the
dispersable resin. The weight ratio of the inorganic particles to
the dispersable resin, which is not particularly limited, is
preferably 50/50<(weight fraction of inorganic
particles)/(weight fraction of dispersable resin)<99.9/0.1, more
preferably 90/10<(weight fraction of inorganic
particles)/(weight fraction of dispersable resin)<99.5/0.5, and
even more preferably 95/5<(weight fraction of inorganic
particles)/(weight fraction of dispersable resin)<99/1. The
dispersable resin to be used here is not particularly restricted
with respect to the type of resin as far as it can be dispersed,
and a wide variety of resins can be used. As to the existence form
of a resin in a solution, a resin dispersable in the form of
particles called suspension or emulsion in a medium is preferably
used. Examples thereof include a fluororesin-based particle
dispersion liquid, a silicone resin-based particle dispersion
liquid, an ethylene-vinyl acetate copolymer resin-based particle
dispersion liquid, and a polyvinylidene chloride resin-based
particle dispersion liquid. Specific examples of the
fluororesin-based particle dispersion liquid include PTFE
dispersion 31-JR, 34-JR produced by Du Pont-Mitsui Fluorochemicals
Co., Ltd. and FluonPTFE dispersion AD911L, AD912L, and AD938L
produced by Asahi Glass Co., Ltd.
[0087] When the coating liquid contains an organic electrolyte, the
content thereof is usually 10 parts by weight or less, preferably 1
part by weight or less based on 100 parts by weight of the liquid
dispersion medium. Addition of a small amount of an organic
electrolyte can make the formation of an inorganic particle
structural body easier and can impart a function of the organic
electrolyte. The organic electrolyte to be used here is not
particularly restricted if it is soluble in a liquid dispersion
medium, and examples thereof include combinations of inorganic
anions, such as BO.sub.3.sup.3-, F.sup.-, PF.sub.6.sup.-,
BF.sub.4.sup.-, AsF.sub.6.sup.-SbF.sub.6.sup.-, ClO.sub.4.sup.-,
AlF.sub.4.sup.-, AlCl.sub.4.sup.-, TaF.sub.6.sup.-,
NbF.sub.6.sup.-, SiF.sub.6.sup.2-, CN.sup.-, and F (HF).sup.n-,
wherein n represents a number of from 1 to 4, with organic cations
described below, combinations of organic anions with organic
cations described below, and combinations of organic anions with
inorganic cations, such as lithium ion, sodium ion, potassium ion,
and hydrogen ion. Organic cations are cationic organic compounds,
examples of which include organic quaternary ammonium cations and
organic quaternary phosphonium cations. Organic quaternary ammonium
cations are quaternary ammonium cations having hydrocarbon groups
selected from the group consisting of alkyl groups (having 1 to 20
of carbon atoms) cycloalkyl groups (having 6 to 20 of carbon atoms)
, aryl groups (having 6 to 20 of carbon atoms) , and aralkyl groups
(having 7 to 20 of carbon atoms) , and organic quaternary
phosphonium cations are quaternary phosphonium cations having
hydrocarbon groups like those described above. The aforementioned
hydrocarbon groups may have a hydroxyl group, an amino group, a
nitro group, a cyano group, a carboxyl group, an ether group, an
aldehyde group, and so on. Organic anions are anions containing
hydrocarbon groups that may have a substituent, and examples
thereof include anions selected from the group consisting of N
(SO.sub.2Rf) .sup.2-, C (SO.sub.2Rf).sup.3-, RfCOO.sup.-, and
RfSO.sup.3-(Rf represents a perfluoroalkyl group having 1 to 12
carbon atoms), and anions resulting from removal of active hydrogen
atoms from organic acids, such as carboxylic acids, organic
sulfonic acids, and organic phosphorus acids, or phenol.
[0088] A coagulant may be added, if necessary, when obtaining a
coating liquid. By the addition of a coagulant, an inorganic
particle structural body with controlled structure can be obtained.
Examples of such a coagulant include an acidic substance such as
hydrochloric acid or its aqueous solution, an alkaline substance
such as sodium hydroxide or its aqueous solution, isopropyl
alcohol, and ionic liquids.
[0089] The coating liquid can be applied by wet coating methods
such as gravure coating, reverse coating, brush roll coating, spray
coating, kiss coating, die coating, dipping, and bar coating. By
using such methods as ink jet printing, screen printing,
flexographic printing, and gravure printing, arbitrary patterns can
be given to an inorganic particle layer. Although the number of
times of applying a coating liquid and the amount of the coating
liquid to be applied in one application are arbitrary, the amount
to be applied in one application is preferably from 0.5 g/m.sup.2
to 40 g/m.sup.2 for applying in a uniform thickness. In the method
of removing the liquid dispersion medium from the applied coating
liquid, that is, the drying method, the pressure and the
temperature of an atmosphere may be chosen appropriately depending
upon the inorganic particles, the metal, and the liquid dispersion
medium to be used. For example, when the liquid dispersion medium
is water, the liquid dispersion medium can be removed at 25.degree.
C. to 60.degree. C. under ordinary pressure.
[0090] In one embodiment of the method of the present invention, an
inorganic particle composite body can be obtained through the
following steps (1) to (3) using an inorganic particle structural
body:
(1) a step of plastically deforming the metal contained in the
structural body, (2) a step of stacking a layer made of inorganic
particles differing in composition from the inorganic particles
contained in the structural body, (3) a step of plastically
deforming the metal contained in the inorganic particle structural
body on which the inorganic particle layer has been stacked.
[0091] By practicing the step (1), the plastically deformed metal
is filled into vacant spaces in the structural body. In some cases,
however, some vacant spaces among many vacant spaces in the
structural body are filled up with metal but the other remain
unfilled with metal, or in some cases a vacant space is partially
filled with metal. Of course, all vacant spaces may be completely
filled up with metal. The degree of plastic deformation of metal or
filling of metal into vacant spaces varies depending upon the
intended function of an inorganic particle composite body.
[0092] There is no limitation on the means for plastically
deforming the metal. Examples thereof include a method comprising
pressurizing an inorganic particle structural body, a method
comprising heating the structural body, a method comprising
irradiating the structural body with an electromagnetic wave, and
methods using these. It is preferred to adopt a method comprising
at least pressurizing as means for plastically deforming metal.
[0093] The aforementioned step (2) is a step of stacking a layer
made of metal and/or inorganic particles differing in composition
from the metal and/or inorganic particles contained in the
inorganic particle structural body. Now, the "metal and/or
inorganic particles differing in composition from the metal and/or
inorganic particles contained in the inorganic particle structural
body" is described.
[0094] First, as to the metal and the inorganic particles contained
in an inorganic particle structural body, the kind and the
proportion thereof are specified. For example, suppose that there
is a structural body including 10% by weight of silver having an
average particle diameter of 5 nm, 60% by weight of silica having
an average particle diameter of 70 nm, 20% by weight of silica
having an average particle diameter of 5 nm, and 10% by weight of
fluororesin having an average particle diameter of 10 nm as an
inorganic particle structural body. In this case, the metal
contains silver having an average particle diameter of 5 nm and the
proportion thereof is 12.5% by weight. Two kinds of silica, i.e. ,
the silica having an average particle diameter of 70 nm and the
silica having an average particle diameter of 5 nm are contained as
inorganic particles; as to the proportions thereof, the former is
75% by weight and the latter is 12.5% by weight. The metal and/or
inorganic particles differing in composition from the metal and/or
inorganic particles contained in the structural body include the
following:
(i) mixed particles failing to contain at least one of silica
having an average particle diameter of 70 nm and silica having an
average particle diameter of 5 nm, (ii) mixed inorganic particles,
a mixture of silica having an average particle diameter of 70 nm
that is the same as the silica having an average particle diameter
of 70 nm contained in the inorganic particle structural body and
silica that is the same as the silica having an average particle
diameter of 5 nm contained in the structural body, wherein the
mixed proportion of the former is not 75% by weight and the mixed
proportion of the latter is not 12.5% by weight, (iii) mixed
particles containing 75% by weight of inorganic particles having an
average particle diameter of 70 nm and 12.5% by weight of inorganic
particles having an average particle diameter of 5 nm, wherein at
least one of them is not silica.
[0095] Examples of the method of stacking, to an inorganic particle
structural body, a layer made of metal and/or inorganic particles
differing in composition from the metal and/or inorganic particles
contained in the structural body include the following methods:
Method 1: a method comprising applying a coating liquid containing
metal and/or inorganic particles and a liquid dispersion medium to
the surface of the inorganic particle structural body and removing
the liquid dispersion medium from the applied coating liquid,
Method 2: a method comprising stacking a plate-shaped material
containing metal and/or inorganic particles to the surface of an
inorganic particle structural body.
[0096] Specifically, wet coating methods, such as a reverse coating
method, a die coating method, a dip coating method, a gravure
coating method, a flexographic coating method, an ink jet coating
method, and a screen printing method, and dry coating methods, such
as a sputtering method, a CVD method, a plasma CVD method, a plasma
polymerization method, and a vacuum deposition method, are
preferably used. These may be used singly or two or more of them
may be used in combination. Step (2) and step (3) each may be
performed two or more times.
[0097] According to the method including the above-described steps
(1) to (3), an inorganic particle composite body can be obtained in
which interlayer adhesion force has been improved while the
property derived from each layer is exerted. Moreover, the
inorganic particle composite body of the present invention can
develop various properties depending upon the kind of inorganic
particles or a metal. In particular, when the same metal has been
filled throughout a plurality of layers as illustrated in FIGS. 5
through 10, the interface between the metal and an inorganic
particle portion of each functional layer is a continuous phase of
the metal, and this probably reduces brittleness or susceptibility
of delamination. When metal fills vacant spaces of an inorganic
particle structural body in a very high filling ratio as
illustrated in FIG. 6, FIG. 8, and FIG. 10, it becomes possible to
form an inorganic particle composite body superior also in
substance barrier property.
[0098] In the step of plastically deforming metal in the method of
the present invention, the inorganic particle structural body is
irradiated with an electromagnetic wave and the metal contained in
the structural body is plastically deformed. An electromagnetic
wave is preferred as means for plastically deforming the metal
because it can be applied selectively to the metal in the
structural body. By applying an electromagnetic wave to an
inorganic particle structural body, it is possible to plastically
deform metal selectively and fill it into at least some of the
vacant spaces contained in the structural body without softening or
melting inorganic particles contained in the structural body. The
electromagnetic wave is preferably at least one selected from the
group consisting of proton beam, electron beam, neutron beam, gamma
rays, X-rays, ultraviolet rays, visible rays, infrared rays,
microwaves, low frequency waves, high frequency waves, and laser
beams thereof. The optimal values of application conditions, such
as the wavelength, output, and application time of an
electromagnetic wave, to be used when an electromagnetic wave is
applied to an inorganic particle structural body vary depending
upon the electromagnetic wave absorbing characteristics of the
inorganic particle structural body, the inorganic particles, and
the metal. By applying an electromagnetic wave within a wavelength
range in which there is a small absorption due to inorganic
particles and there is a large absorption due to metal, it is
possible to plastically deform the metal efficiently without
damaging inorganic particles, an inorganic particle structural
body, or an inorganic particle composite body to be formed.
[0099] In addition to electromagnetic wave irradiation, an
auxiliary method may be used in order to make plastic deformation
of the metal easier. Examples of such an auxiliary method include a
method comprising adding heat to soften metal, a method comprising
applying a chemical to soften metal, and a method comprising
increasing the affinity or slipping property at the interface of
metal and a vacant space; among these the method comprising adding
heat to soften metal is preferably used. Examples of the method of
heating the whole of an inorganic particle structural body to
soften metal include a method comprising feeding the structural
body into a heating atmosphere using an oven, a heater, or the like
and a method comprising bringing the structural body into contact
with a heat medium, such as a heated metal plate or roll.
[0100] In one preferred embodiment of the method of the present
invention, the surface of the structural body obtained by
practicing the step of plastically deforming metal is
hydrophilized, and in another preferred embodiment of the method of
the present invention, a step of hydrophilizing the surface of the
inorganic particle structural body is carried out prior to the
execution of the step of plastically deforming metal. The
hydrophilization may be performed to either a part of the surface
of an inorganic particle structural body or the whole of the
surface. The hydrophilization in the present invention is not
particularly restricted if it is a treatment to improve the
hydrophilicity of the surface of an inorganic particle structural
body. Preferable examples include a method comprising coating the
surface of an inorganic particle structural body with a
hydrophilizing agent, and cleaning of the surface of a structural
body with a solvent, or the like. Hydrophilic inorganic particles
may be used as the hydrophilizing agent for coating the surface of
an inorganic particle structural body. A hydrophilic inorganic
particle is a particle that has a hydrophilic group and is high in
affinity to water and examples thereof include calcium carbonate,
titanium dioxide, talc, aluminum silicate, calcium silicate,
alumina silica trihydrate, alumina, zirconia, ceria, silica,
calcium sulfate, and glass microspheres.
[0101] The mechanism of coating the surface of an inorganic
particle structural body with a hydrophilizing agent is not
particularly restricted; it is permitted to make the surface of the
inorganic particle structural body adsorb the hydrophilizing agent
physically and also permitted to react the surface of the inorganic
particle structural body with the hydrophilizing agent (chemical
adsorption). The method of coating the surface of an inorganic
particle structural body with a hydrophilizing agent is not
particularly restricted, and wet coating methods, such as a reverse
coating method, a die coating method, a dip coating method, a
gravure coating method, a flexographic coating method, an ink jet
coating method, and a screen printing method, and dry coating
methods, such as a sputtering method, a CVD method, a plasma CVD
method, a plasma polymerization method, and a vacuum deposition
method, are preferably used. The thickness of the layer of a
hydrophilizing agent to be provided, which is not particular
limited, is preferably from 1 to about 50 nm; if the layer is
excessively thick, it becomes difficult to develop surface
hardness, whereas if it is thinner than 1 nm, hydrophilicity may
not be developed enough. The thickness is more preferably from 2 to
30 nm, particularly preferably from 3 to about 10 nm.
[0102] The cleaning method, which is one option of the
hydrophilization of the present invention is not particularly.
restricted; contact cleaning methods such as solvent cleaning
treatment and adhesive roll dust removing treatment, and
non-contact cleaning methods such as UV irradiation, corona
treatment, plasma treatment, flame plasma treatment, and ultrasonic
dust removing treatment, are preferably used. Two or more
techniques may be used together as hydrophilization.
[0103] In an embodiment of the present invention where
hydrophilization is applied, it is preferred to use an inorganic
particle structural body, at least a part of the surface of which
is constituted of an inorganic particle layer. This is because
inorganic particle layers are easy to apply hydrophilization
thereto since inorganic particles have been exposed. The
hydrophilic inorganic particle composite body of the present
invention is an object in a state that some of inorganic particles
have been bonded together chemically and/or physically via
metal.
[0104] In one preferred embodiment of the method of the present
invention, the surface of the structural body obtained by
practicing the step of plastically deforming metal is
hydrophobized, and, in another preferred embodiment of the method
of the present invention, a step of hydrophilizing the surface of
the inorganic particle structural body is carried out prior to the
execution of the step of plastically deforming metal.
[0105] The method of hydrophobizing the surface of an inorganic
particle structural body is not particularly restricted.
[0106] Preferred is a method comprising stacking a layer containing
a hydrophobilizing agent to the surface of a structural body and a
method comprising reacting a hydrophobizing agent. The
hydrophobization may be performed to either a part of the surface
of an inorganic particle structural body or the whole of the
surface.
[0107] As a method for stacking a layer containing a hydrophobizing
agent, wet coating methods, such as a reverse coating method, a die
coating method, a dip coating method, a gravure coating method, a
flexographic coating method, an ink jet coating method, and a
screen printing method, and dry coating methods (i.e., vapor
deposition methods), such as a sputtering method, a CVD method, a
plasma CVD method, a plasma polymerization method, and a vacuum
deposition method, are preferably used. The thickness of the
hydrophobizing agent layer to be formed on the surface of an
inorganic particle structural body, which is not particularly
limited, is preferably from 1 to about 50 nm; if it is excessively
thick, surface hardness becomes difficult to develop, whereas if it
is less than 1 nm, hydrophobicity is poor. The thickness is more
preferably from 2 to 30 nm, particularly preferably from 3 to about
10 nm.
[0108] As such a hydrophobizing agent, compounds that contain a
fluorine atom and that have low surface energy and low interfacial
energy are preferred, examples of which compounds include silicone
compounds having a fluorinated hydrocarbon group and polymers
containing a fluorinated hydrocarbon group. A fluorine-containing
surface-antifouling agent, OPTOOL DSX produced by Daikin
Industries, Ltd., and so on can be obtained as commercially
available products.
[0109] Examples of other preferred hydrophobizing agent include
fluorine-containing silicon compounds having two or more silicon
atoms such as those disclosed in JP 2009-53591 A. In the case that
an inorganic particle structural body is coated with this type of
compound, the chemical adsorption to the inorganic particle
structural body does not differ from the case that only one silicon
atom is contained because silicon atoms bond each other to form a
long chain. Even if, however, the inorganic particle structural
body forms almost no bond with silicon atoms, the silicon atoms
bond together to form a long chain to adsorb to the structural body
physically, so that a film that is relatively highly resistant to
wiping can be formed. For this reason, fluorine-containing silicon
compounds having two or more silicon atoms bonded to reactive
functional groups are suitable.
[0110] Specific examples of the fluorine-containing silicon
compound having two or more silicon atoms bonded to a reactive
functional group include
[0111]
(CH.sub.3O).sub.3SiCH.sub.2CH.sub.2CH.sub.2OCH.sub.2CF.sub.2CF.sub.-
2O (CF.sub.2CF.sub.2CF.sub.2O)
pCF.sub.2CF.sub.2CH.sub.2OCH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.3).sub.3,
[0112]
(CH.sub.3O).sub.2CH.sub.3SiCH.sub.2CH.sub.2CH.sub.2OCH.sub.2CF.sub.-
2CF.sub.2O (CF.sub.2CF.sub.2CF.sub.2O)
pCF.sub.2CF.sub.2CH.sub.2OCH.sub.2CH.sub.2CH.sub.2SiCH.sub.3
(OCH.sub.3).sub.2,
[0113]
(CH.sub.3O).sub.3SiCH.sub.2CH.sub.2CH.sub.2OCH.sub.2CF.sub.2(OC.sub-
.2F.sub.4)q(OCF.sub.2)rOCF.sub.2CH.sub.2OCH.sub.2CH.sub.2CH.sub.2Si(OCH.su-
b.3).sub.3,
[0114] (CH.sub.3O)
.sub.2CH.sub.3SiCH.sub.2CH.sub.2CH.sub.2OCH.sub.2CF.sub.2(0C.sub.2F.sub.4-
) q (OCF.sub.2)
rOCF.sub.2CH.sub.2OCH.sub.2CH.sub.2CH.sub.2SiCH.sub.3(OCH.sub.3).sub.2,
[0115]
(C.sub.2H.sub.5O).sub.3SiCH.sub.2CH.sub.2CH.sub.2OCH.sub.2CF.sub.2(-
OC.sub.2F.sub.4)q(OCF.sub.2)rOCF.sub.2CH.sub.2OCH.sub.2CH.sub.2CH.sub.2Si(-
OC.sub.2H.sub.5).sub.3,
[0116]
(CH.sub.3O).sub.3SiCH.sub.2C(.dbd.CH.sub.2)CH.sub.2CH.sub.2CH.sub.2-
OCH.sub.2CF.sub.2CF.sub.2O(CF.sub.2CF.sub.2CF.sub.2O)pCF.sub.2CF.sub.2CH.s-
ub.2OCH.sub.2CH.sub.2CH.sub.2(CH.sub.2.dbd.)
CCH.sub.2Si(OCH.sub.3).sub.3,
[0117] (CH.sub.3O).sub.3SiCH.sub.2C
(.dbd.CH.sub.2)CH.sub.2CH.sub.2CH.sub.2OCH.sub.2CF.sub.2(OC.sub.2F.sub.4)-
q(OCF.sub.2)rOCF.sub.2CH.sub.2OCH.sub.2CH.sub.2CH.sub.2(CH.sub.2.dbd.)CCH.-
sub.2Si(OCH.sub.3).sub.3, and
[0118]
(CH.sub.3O).sub.2CH.sub.3SiCH.sub.2C(.dbd.CH.sub.2)CH.sub.2CH.sub.2-
CH.sub.2OCH.sub.2CF.sub.2(OC.sub.2F.sub.4)q(OCF.sub.2)rOCF.sub.2CH.sub.2OC-
H.sub.2CH.sub.2CH.sub.2(CH.sub.2.dbd.)
CCH.sub.2SiCH.sub.3(OCH.sub.3).sub.2. It is noted that p is an
integer of from 1 to 50, q is an integer of from 1 to 50, r is an
integer of from 1 to 50, q+r is an integer of from 10 to 100, and
the sequence of the repeating units in the formulae is random.
[0119] Although the contact angle with pure water of the surface of
the hydrophobic inorganic particle composite body to be produced by
the method of the present invention is not particularly limited, it
is preferred, from the viewpoint of water proofing property and
antifouling property, to be 100.degree. or more and the contact
angle with oleic acid is preferably 70.degree. or more. Besides the
above, a method comprising forming a monomolecular film possessing
a water-repellent function like those disclosed in JP 2008-273784
A, JP 2008-7365 A, and JP 2006-223957 A, a method comprising
forming a functional organic thin film like that disclosed in JP
2006-188487 A, and a method comprising forming a fractal surface
structure like those disclosed in WO2005/027611 and JP 8-323280 A
may be used as a method for hydrophobilizing at least a part of the
surface of a structural body or a composite body.
[0120] There is no particular limitation on the shape of
hydrophobic inorganic particle composite bodies to be produced by
the method of the present invention and a shape according to a
required function and an intended application is used. Examples
thereof include a tabular shape such as film and sheet, a rod-like
shape, a fibrous shape, a spherical shape, and a three-dimensional
structure shape. In the case that the intended application is a
flat-panel display, a flexible display, or the like, it is
preferred that the shape of a hydrophobic inorganic particle
composite body be a film-like shape. An inorganic particle
structural body to be used preferably has an inorganic particle
layer on its surface. In this case, the thickness of the inorganic
particle layer, which is not particularly limited, is 100 .mu.m or
less, preferably 10 .mu.m or less, more preferably 5 .mu.m or less,
and particularly preferably 1 .mu.m or less. In the case that
flexibility or the like is further required, the thickness of the
inorganic particle layer is 5 .mu.m or less, preferably 1 .mu.m or
less, more preferably 0.5 .mu.m or less, and particularly
preferably 0.2 .mu.m or less. When the thickness of an inorganic
particle layer is greater than 100 .mu.m, the layer tends to become
brittle, whereas when it is 0.01 .mu.m or less, hardness tends to
be difficult to develop.
[0121] According to the method of the present invention, it is
possible to obtain a hydrophobic inorganic particle composite body
having reduced brittleness or reduced ease in peeling while having
surface hardness derived from inorganic particles. Moreover, a
hydrophobic inorganic particle composite body to be produced by the
method of the present invention can develop various properties
depending upon the kind of hydrophobization, inorganic particles or
metal. When metal fills vacant spaces of an inorganic particle
structural body in a very high filling ratio as illustrated in FIG.
2 and FIG. 4, it becomes possible to form a hydrophobic inorganic
particle composite body superior also in substance barrier
property.
[0122] In one preferred embodiment of the method of the present
invention, the surface of the structural body obtained by
practicing the step of plastically deforming metal is subjected to
an antireflecting treatment, and in another preferred embodiment of
the method of the present invention, a step of applying an
antireflecting treatment to the surface of the inorganic particle
structural body is carried out prior to the execution of the step
of plastically deforming metal.
[0123] Representative schematic diagrams of an antireflective
inorganic particle composite body are shown in FIGS. 15 and 16, but
the present invention is not restricted to these. Moreover, a
product in which some of the composite bodies illustrated in these
representative schematic diagrams have been combined can also be
used.
[0124] The inorganic particle composite body obtained through the
steps of the present invention may be an inorganic particle
composite body obtained by using an inorganic particle structural
body having an inorganic particle layer in at least part of the
surface thereof among the above-described inorganic particle
structural bodies, plastically deforming the metal contained in the
inorganic particle structural body, thereby filling the metal into
at least some of the vacant spaces contained in the inorganic
particle structural body and oozing the metal to the surface of the
inorganic particle structural body. That is, the inorganic particle
composite body has been covered on at least part of its surface
with the metal contained in the inorganic particle structural body
used. It is preferred in the present invention to obtain an
inorganic particle composite body having, in at least part of its
surface, a layer where inorganic particles derived from an
inorganic particle structural body has been exposed. Such an
inorganic particle composite body is easy to apply antireflecting
treatment. The method of stacking an antireflecting agent on the
surface of an inorganic particle composite body is not particularly
restricted. Preferably used are a method comprising applying a
coating liquid containing an antireflecting agent to the surface of
an inorganic particle structural body and then drying it, wet
coating methods, such as a reverse coating method, a die coating
method, a dip coating method, a gravure coating method, a
flexographic coating method, an ink jet coating method, and a
screen printing method, and dry coating methods (i.e., vapor
deposition) , such as a sputtering method, a CVD method, a plasma
CVD method, a plasma polymerization method, and a vacuum deposition
method. These may be used singly or two or more of them may be used
in combination.
[0125] A layer to be stacked and made of an antireflecting agent is
designed in consideration of various factors, such as the
wavelength of the light to be antireflected, the index of
refraction of the inorganic particle composite body to be used, and
the index of refraction of the atmosphere in which an
antireflective inorganic particle composite body is used. The
antireflective layer to be stacked may have either a single layer
or multiple layers. In the case of a single layer, a composition
that affords a low refractive index is used. In the case of
multiple layers, the refractive index and the thickness of each
layer are determined depending upon optical design. A multilayer is
better in antireflecting property, whereas a single layer is better
in cost. For example, in the case of preventing the reflection of a
visible radiation by a single-layer antireflective layer, it is
preferred to adjust the thickness of the antireflective layer to
from 50 to 150 nm, more preferably from 80 to 130 nm. As to an
optical design method, "Characteristics and optimum design of
antireflection film/film formation technology"(2001, Technical
Information Institute Co., Ltd.), "Optical practical materials -
with an eye to various application development--" (2006, Johokiko
Co., Ltd.), and "Characteristics and optimum design of
antireflection film/film formation technology"(2001, edited by
Technical Information Institute Co., Ltd.) can be referred to.
[0126] Although the method disclosed in JP 2006-327187 A is
described in detail below as one example of antireflecting
treatment, the antireflecting treatment in the present invention is
not limited thereto.
[0127] The mixed inorganic particle dispersion liquid to be used as
an antireflecting agent is prepared using inorganic particle chains
(A) each composed of three or more particles with a particle
diameter of 10 to 60 nm connected in a chain form, inorganic
particles (B) with an average particle diameter of 1 to 20 nm, and
a liquid dispersion medium and satisfies the following formulae (1)
and (2).
0.55.ltoreq.RVa.ltoreq.0.90 (1)
0.10.ltoreq.RVb.ltoreq.0.45 (2)
wherein RVa is the ratio of the volume of the inorganic particle
chains (A) to the total volume of the inorganic particle chains (A)
and the inorganic particles (B) in the dispersion liquid, and RVb
is the ratio of the volume of the inorganic particles (B) to the
total volume of the inorganic particle chains (A) and the inorganic
particles (B) in the dispersion liquid.
[0128] The chemical composition of the inorganic particle chains
(A) may be either the same as or different from the chemical
composition of the inorganic particles (B). Examples of inorganic
particles which are used as the inorganic particle chains (A) or
the inorganic particles (B) include silicon oxide (i.e., silica),
titanium oxide, aluminum oxide, zinc oxide, tin oxide, Calcium
carbonate, barium sulfate, talc, and kaolin. The inorganic particle
chains (A) and the inorganic particles
[0129] (B) are preferably made of silica because particles thereof
are high in dispersibility in a solvent, low in refractive index,
and easy to obtain a powder being small in particle size
distribution. An inorganic particle chain (A) is a chain in which
three or more inorganic particles with a particle diameter of 10 to
60 nm are connected in a chain form. As such inorganic particle
chains can be used commercially available products, examples of
which include SNOWTEX (registered trademark) PS-S, PS-SO, PS-M, and
PS-MO produced by Nissan Chemical Industries, Ltd., which are
silica sols containing water as a dispersion medium, and IPA-ST-UP
produced by Nissan Chemical Industries, Ltd., which is silica sol
containing isopropanol as a dispersion medium. The particle
diameter of the particles forming inorganic particle chains and the
shape of the inorganic particle chain can be determined through
observation using a transmission electron microscope. The
expression "connected in a chain form" as used herein is an
expression opposite to "connected in a circular form" and
encompasses not only particles connected in a straight form but
also particles connected in a bent form.
[0130] The average particle diameter of the inorganic particles (B)
is from 1 to 20 nm. The average particle diameter of the inorganic
particles (B) is determined by the dynamic light scattering method
or the Sears method. Measurement of the average particle diameter
by the dynamic light scattering method can be performed by using a
commercially available particle size distribution analyzer. The
Sears method, which is disclosed in Analytical Chemistry, Vol. 28,
p. 1981-1983, 1956, is an analytical method to be applied to the
measurement of the average particle diameter of silica particles;
it is a method in which the surface area of particles is determined
from the amount of NaOH to be consumed for adjusting a colloidal
silica dispersion liquid from pH=3 to pH=9 and then a sphere
equivalent diameter is calculated from the determined surface area.
A spherical equivalent diameter determined in the above way is
defined an average particle diameter.
[0131] Typically, the mixed inorganic particle dispersion liquid
can be prepared by, for example, any of the following methods [1]
through [5], but the preparation is not limited to these
methods.
[1] A method comprising adding a powder of inorganic particle
chains (A) and a powder of inorganic particles (B) simultaneously
to a common liquid dispersion medium and then dispersing them. [2]
A method comprising dispersing inorganic particle chains (A) in a
first liquid dispersion medium to prepare a first dispersion
liquid, separately dispersing inorganic particles (B) in a second
liquid dispersion medium to prepare a second dispersion liquid, and
then mixing the first and the second dispersion liquids. [3] A
method comprising dispersing inorganic particle chains (A) in a
liquid dispersion medium to prepare a dispersion liquid, and then
adding a powder of inorganic particles (B) to the dispersion liquid
to disperse. [4] A method comprising dispersing inorganic particles
(B) in a liquid dispersion medium to prepare a dispersion liquid,
then adding a powder of inorganic particle chains (A) to the
dispersion liquid to dispersed. [5] A method comprising performing
grain growth in a dispersion medium to prepare a first dispersion
liquid containing inorganic particle chains (A), separately
performing grain growth in a dispersion medium to prepare a second
dispersion liquid containing an inorganic particles (B), and then
mixing the first and second dispersion liquids.
[0132] By applying strong dispersion means, such as ultrasonic
dispersion and ultrahigh pressure dispersion, it is possible to
disperse inorganic particles particularly uniformly in a mixed
inorganic particle dispersion liquid. In order to achieve
dispersion with higher uniformity, it is preferred that inorganic
particles in the dispersion liquid of inorganic particle chains (A)
and the dispersion liquid of inorganic particles (B) to be used for
the preparation of a mixed inorganic particle dispersion liquid and
in a mixed inorganic particle dispersion liquid to be obtained
finally be in a colloidal state. Water and a volatile organic
solvent can be used as a dispersion medium.
[0133] In the aforementioned method [2], [3], [4], or [5], when the
dispersion liquid of the inorganic particle chains (A) , the
dispersion liquid of the inorganic particles (B) , or both the
dispersion liquid of the inorganic particle chains (A) and the
dispersion liquid of the inorganic particles (B) are colloidal
alumina, it is preferred to add an anion, such as chlorine ion,
sulfate ion, and acetate ion, as a counter anion, to the colloidal
alumina in order to stabilize alumina particles to be positively
charged. Although the colloidal alumina is not particularly limited
with respect to pH, it preferably has a pH of 2 to 6 from the
viewpoint of the stability of a dispersion liquid. Moreover, also
in the aforementioned method [1] , when at least one of the
inorganic particle chains (A) and the inorganic particles (B) is
alumina and the mixed inorganic particle dispersion liquid is in a
colloidal state, it is preferred to add an anion, such as chlorine
ion, sulfate ion, and acetate ion, to the mixed inorganic particle
dispersion liquid.
[0134] In the aforementioned method [2], [3], [4], or [5], when the
dispersion liquid of the inorganic particle chains (A) , the
dispersion liquid of the inorganic particles (B) , or both the
dispersion liquid of the inorganic particle chains (A) and the
dispersion liquid of the inorganic particles (B) are colloidal
silica, it is preferred to add a cation, such as ammonium ion,
alkali metal ion, and alkaline earth metal ion, as a counter
cation, to the colloidal silica in order to stabilize silica
particles to be negatively charged. Although the colloidal silica
is not particularly limited with respect to pH, it preferably has a
pH of 8 to 11 from the viewpoint of the stability of a dispersion
liquid. Moreover, also in the aforementioned method [1], when at
least one of the inorganic particle chains (A) and the inorganic
particles (B) is silica and the mixed inorganic particle dispersion
liquid is in a colloidal state, it is preferred to add a cation,
such as ammonium ion, alkali metal ion, and alkaline earth metal
ion, to the mixed inorganic particle dispersion liquid.
[0135] The mixed inorganic particle dispersion liquid satisfies the
following formulae (1) and (2):
0.55.ltoreq.RVa.ltoreq.0.90 (1)
0.10.ltoreq.RVb.ltoreq.0.45 (1)
wherein RVa is the ratio of the volume of the inorganic particle
chains (A) to the total volume of the inorganic particle chains (A)
and the inorganic particles (B) in the dispersion liquid, and RVb
is the ratio of the volume of the inorganic particles (B) to the
total volume of the inorganic particle chains (A) and the inorganic
particles (B) in the dispersion liquid. In other words, RVa and RVb
in the above formulae are equivalent to the volume fraction of the
inorganic particle chains (A) and the volume fraction of the
inorganic particles (B), respectively. If the inorganic particle
chains (A) and the inorganic particles (B) are of the same chemical
species, the volume fractions (RVa and RVb) of the inorganic
particle chains (A) and the inorganic particles (B) are generally
equal to the weight fractions of the inorganic particle chains (A)
and the inorganic particles (B). Although the amount of the
inorganic particle chains (A) and the inorganic particles (B)
contained in the mixed inorganic particle dispersion liquid is not
particularly limited, it is preferably from 1 to 20% by weight and
more preferably from 3 to 10% by weight from the viewpoint of
application property and dispersibility.
[0136] Additives, such as a surfactant and an organic electrolyte,
may be added to the mixed inorganic particle dispersion liquid for
the purpose of stabilization of the dispersion of inorganic
particles, and so on. When the mixed inorganic particle dispersion
liquid contains a surfactant, the content thereof is usually 0.1
parts by weight or less to 100 parts by weight of the dispersion
medium. The surfactant to be used is not particularly restricted
and examples thereof include anionic surfactants, cationic
surfactants, nonionic surfactants, and ampholytic surfactants. The
compounds provided below as examples can be used as the
surfactant.
[0137] Surfactants include cationic surfactants, anionic
surfactants, amphoteric surfactants, and nonionic surfactants, and
there are no particular limitations. From the viewpoint of
compatibility with resin and thermal stability, nonionic
surfactants are preferably used.
[0138] Specific examples include: sorbitan based surfactants such
as sorbitan fatty acid esters, e.g., sorbitan monopalmitate,
sorbitan monostearate, sorbitan monopalmitate, sorbitan
monomontanate, sorbitan monooleate, and sorbitan dioleate, and
alkylene oxide adducts thereof; glycerol-based surfactants such as
glycerol fatty acid esters, e.g. glycerol monopalmitate, glycerol
monostearate, diglycerol distearate, triglycerol monostearate,
tetraglycerol dimontanate, glycol monooleate, diglycerol
monooleate, diglycerol sesquioleate, tetraglycerol monooleate,
hexaglycerol monooleate, hexaglycerol trioleate, tetraglycerol
trioleate, tetraglycerol monolaurate and hexaglycerol monolaurate,
and their alkylene oxide adducts; polyethylene glycol-based
surfactants such as polyethylene glycol monopalmitate and
polyethylene glycol monostearate; alkylene oxide adducts of
alkylphenols; esters of sorbitan/glycerol condensates with organic
acids; polyoxyethylene alkylamines, such as polyoxyethylene (2 mol)
stearylamine, polyoxyethylene (4 mol) stearylamine, polyoxyethylene
(2 mol) stearylamine monostearate, polyoxyethylene (4 mol)
laurylamine monosterarate, and their fatty acid esters. Other
examples include fluorine compounds having a perfluoroalkyl group,
an .omega.-hydrofluoroalkyl group, or the like (especially,
fluorine-containing surfactants), and silicone type compounds
having an alkylsiloxane group (especially, silicone type
surfactants). Specific examples of fluorine-containing surfactants
include UNIDYNE DS-403, DS-406, DS-401 (trade names) produced by
Daikin Industries, Ltd., and SURFLON KC-40 (trade name) produced by
SEIMI CHEMICAL Co., Ltd. Examples of silicone type surfactants
include SH-3746 (trade name) produced by Toray Dow Corning Silicone
Co.
[0139] When the mixed inorganic particle dispersion liquid contains
an organic electrolyte, the content thereof is usually 0.01 parts
by weight or less based on 100 parts by weight of the liquid
dispersion medium. The compounds provided below as examples can be
used as the organic electrolyte. The organic electrolyte to be used
here is not particularly restricted if it has been dissolved in a
liquid, and examples thereof include combinations of inorganic
anions, such as BO.sub.3.sup.3-, F.sup.-, PF.sub.6.sup.-,
BF.sub.4.sup.-, AsF.sub.6.sup.-, SbF.sub.6.sup.-, ClO.sub.4.sup.-,
AlF.sub.4.sup.-, AlCl.sub.4.sup.-, TaF.sub.6.sup.-,
NbF.sub.6.sup.-, SiF.sub.6.sup.2-, CN.sup.-, and F(HF).sup.n-,
wherein n represents a number of from 1 to 4, with organic cations
described below, combinations of organic anions with organic
cations described below, and combinations of organic anions with
inorganic cations, such as lithium ion, sodium ion, potassium ion,
and hydrogen ion.
[0140] Organic cations are cationic organic compounds, examples of
which include organic quaternary ammonium cations and organic
quaternary phosphonium cations. Organic quaternary ammonium cations
are quaternary ammonium cations having hydrocarbon groups selected
from the group consisting of alkyl groups (having 1 to 20 of carbon
atoms), cycloalkyl groups (having 6 to 20 of carbon atoms), aryl
groups (having 6 to 20 of carbon atoms), and aralkyl groups (having
7 to 20 of carbon atoms), and organic quaternary phosphonium
cations are quaternary phosphonium cations having hydrocarbon
groups like those described above. The aforementioned hydrocarbon
groups may have a hydroxyl group, an amino group, a nitro group, a
cyano group, a carboxyl group, an ether group, an aldehyde group,
and so on.
[0141] Organic anions are anions containing hydrocarbon groups that
may have a substituent, and examples thereof include anions
selected from the group consisting of N(SO.sub.2Rf).sup.2-,
C(SO.sub.2Rf).sup.3-, RfCOO.sup.-, and RfSO.sup.3- (Rf represents a
perfluoroalkyl group having 1 to 12 carbon atoms), and anions
resulting from removal of active hydrogen atoms from organic acids,
such as carboxylic acids, organic sulfonic acids, and organic
phosphorus acids, or phenol.
[0142] An inorganic particle layer is formed on an inorganic
particle composite body by applying a mixed inorganic particle
dispersion liquid prepared using the aforementioned inorganic
particle chains (A) , inorganic particles (B) , and dispersion
liquid medium onto the inorganic particle composite body, and
subsequently removing the liquid dispersion medium by suitable
means from the applied mixed inorganic particle dispersion liquid.
An antireflective inorganic particle composite body is thereby
formed because that inorganic particle layer has an antireflecting
function. The thickness of the inorganic particle layer with such
an antireflecting function is not particularly limited. In the
production of an antireflective inorganic particle composite body
suitable for use as a surface layer of a display in order to
effectively prevent the reflection of extraneous light inside the
display, the thickness of the inorganic particle layer in the
antireflective inorganic particle composite body is adjusted
preferably to 50 to 150 nm and more preferably to 80 to 130 nm. The
thickness of the inorganic particle layer can be adjusted by
changing the amounts of the inorganic particle chains (A) and the
inorganic particles (B) in the mixed inorganic particle dispersion
liquid and the applied amount of the mixed inorganic particle
dispersion liquid.
[0143] The method of applying the mixed inorganic particle
dispersion liquid to the surface of the inorganic particle
composite body is not particularly restricted, and the liquid can
be applied by a wet coating method, such as gravure coating,
reverse coating, brush roll coating, spray coating, kiss coating,
die coating, dipping, and bar coating.
[0144] It is preferred to apply pretreatment, such as corona
treatment, ozonization, plasma treatment, flame treatment, electron
beam treatment, anchor coat treatment, and rinsing, to the surface
of the inorganic particle composite body prior to the application
of the mixed inorganic particle dispersion liquid to the inorganic
particle composite body.
[0145] By removing the liquid dispersion medium from the mixed
inorganic particle dispersion liquid applied to the inorganic
particle composite body, an inorganic particle layer is formed on
the inorganic particle composite body. The removal of the liquid
dispersion medium can be executed, for example, by heating
performed under normal pressure or reduced pressure. The pressure
and the heating temperature to be used in the removal of the liquid
dispersion medium may be chosen appropriately according to the
materials to be used (that is, the inorganic particle chains (A),
the inorganic particles (B), and the liquid dispersion medium). For
example, when the dispersion medium is water, drying may be done at
50 to 80.degree. C., preferably at about 60.degree. C. By using the
method of JP 2006-327187 A, it is possible to form an inorganic
particle layer having an antireflection function and being superior
in hardness on an inorganic particle composite body without
performing treatment at high temperature higher than 200.degree. C.
This probably is because the formed inorganic particle layer has a
structure in which the inorganic particles (B) are located in the
gaps of the inorganic particle chains (A) and the inorganic
particle chains (A) are bound via the inorganic particles (B) .
[0146] To an antireflective inorganic particle composite body to be
produced by the method of the present invention may be applied
antifouling treatment, antistatic treatment, etc., if necessary.
Antifouling treatment is a treatment for preventing fingerprint
attachment or the like or making it easy to wipe away fingerprint
soil and it can be done by coating the surface of an antireflective
inorganic particle composite body with a hydrophobizing agent or
the like or reacting a hydrophobizing agent to the surface of the
composite body. By doing antistatic treatment, it is possible to
prevent dusts from attaching for securing visibility and to prevent
optical elements from being broken by discharge caused by
electrification. Addition and lamination of the aforementioned
surfactant or a conducting material is often done as antistatic
treatment.
[0147] Although the contact angle with pure water of the surface of
the antireflective inorganic particle composite body to be produced
by the method of the present invention is not particularly limited,
it is preferred, from the viewpoint of water proofing property and
antifouling property, to be 100.degree. or more and the contact
angle with oleic acid is preferably 70.degree. or more.
[0148] In one preferred embodiment of the method of the present
invention, a glass layer is given to the surface of the structural
body obtained by practicing the step of plastically deforming
metal, and in another preferred embodiment of the method of the
present invention, a step of giving a glass layer to the surface of
the inorganic particle structural body is carried out prior to the
execution of plastically deforming metal. Schematic diagrams of
representative embodiments of an inorganic particle composite body
with glass stacked are shown in FIGS. 17 and 18, but the present
invention is not restricted to these. Moreover, a product in which
some of the composite bodies illustrated in these representative
schematic diagrams have been combined may also be used.
[0149] The inorganic particle composite body to be produced by the
method of the present invention may be an inorganic particle
composite body obtained by using an inorganic particle structural
body having an inorganic particle layer in at least part of the
surface thereof, plastically deforming the metal contained in the
inorganic particle structural body, thereby filling the metal into
at least some of the vacant spaces contained in the inorganic
particle structural body without allowing the metal to ooze out to
the surface of the inorganic particle structural body. That is, the
inorganic particle composite body has, in at least part of the
surface thereof, an inorganic particle layer derived from an
inorganic particle structural body.
[0150] The inorganic particle composite body to be produced by the
method of the present invention may be an inorganic particle
composite body obtained by using an inorganic particle structural
body having an inorganic particle layer in at least part of the
surface thereof, plastically deforming the metal contained in the
inorganic particle structural body, thereby filling the metal into
at least some of the vacant spaces contained in the inorganic
particle structural body and oozing the metal to the surface of the
inorganic particle structural body. That is, the inorganic particle
composite body has been covered on at least part of its surface
with the metal contained in the inorganic particle structural body
used.
[0151] It is preferred in the present invention to obtain an
inorganic particle composite body having, in at least part of its
surface, an inorganic particle layer derived from an inorganic
particle structural body. Such an inorganic particle composite body
is easy to stack with a glass layer. Although the method of
stacking an inorganic particle composite body with glass is not
particularly restricted, a method comprising bonding an inorganic
particle composite body to glass via an adhesive, a method
comprising coating an inorganic particle composite body with a
glass precursor and then converting the glass precursor into glass,
and a method comprising extrusion-laminating molten glass to an
inorganic particle composite body are preferred as described
below.
[0152] Examples of the method comprising bonding an inorganic
particle composite body to glass via an adhesive include a method
comprising applying an adhesive to a surface of the inorganic
particle composite body, and then curing the adhesive with the
applied portion stacked on glass, a method comprising applying an
adhesive to glass, and then curing the adhesive with the applied
portion stacked on the surface of an inorganic particle composite
body, and a method comprising applying an adhesive to both glass
and an inorganic particle composite body, and then curing the
adhesive with their applied portions kept in contact with each
other. The kind of the adhesive is not particularly restricted.
Ceramics, water glass, rubber-based adhesives, epoxy type
adhesives, acrylic adhesives, urethane type adhesives, and the like
can be used. Use of a water-soluble adhesive is preferred in ease
to handle. Examples of the water-soluble adhesive include glue,
starch, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide,
and acrylamide-diacetone acrylamide copolymers. Moreover, the
adhesive can contain additives such as a tackifier, a plasticizer,
a filler, an antioxidant, a stabilizer, a pigment, diffusion
particles, a curing agent, and a solvent. The thickness of the
adhesive layer, which is not particularly limited, is preferably up
to 100 nm.
[0153] The composition, the production method and so on of glass
that can be used are not particularly restricted. Soda glass,
crystal glass, borosilicate glass, quartz glass, aluminosilicate
glass, borate glass, phosphate glass, alkali-free glass, composite
glass with ceramics, and the like can be used.
[0154] The method comprising coating an inorganic particle
composite body with a glass precursor and then converting the glass
precursor into glass is not particularly restricted. Examples
thereof include heating by an oven or the like and local heating of
the glass precursor by electromagnetic wave radiation or the like.
Silane compounds, metal alkoxides, water glass, glass paste, and so
on can be used as the glass precursor. Example of the silane
compounds include tetramethoxysilane, tetraethoxysilane,
methyltrimetoxysilane, phenyltrimethoxysilane,
vinyltrimethoxysilane, 3-glycidoxypropyltrimetoxysilane,
p-styryltrimethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane,
3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane,
3-chloropropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane,
and 3-isocyanatopropyltriethoxysilane. Examples of the metal
alkoxides include alkoxides of titanium (e.g.,
tetraisopropoxytitanium), alkoxides of zirconium (e.g.,
tetra-n-butoxyzirconium), alkoxides of aluminum (e.g.,
tri-sec-butoxyaluminum), and condensates thereof. Such a condensate
may be either a condensate of a single kind of compound or a
complex condensate of two or more compounds. Silane compounds and
metal alkoxides may be used in the form of a solution. The method
of coating an inorganic particle composite body with a glass
precursor is not particularly restricted. Wet coating methods, such
as a reverse coating method, a die coating method, a dip coating
method, a gravure coating method, a flexographic coating method, an
ink jet coating method, and a screen printing method, are
preferably used.
[0155] The method of extrusion-laminating molten glass to an
inorganic particle composite body is not particularly
restricted.
[0156] While the inorganic particle composite body to be produced
by the method of the present invention is not particularly limited
with respect to its voidage, the voidage is preferably 90% by
volume or less, more preferably 50% by volume or less, even more
preferably 30% by volume or less, particularly 10% by volume or
less, and most preferably 5% by volume or less or 1% by volume or
less.
[0157] When the voidage is higher than 90% by volume, strength as
an inorganic particle composite body tends to be short. An
inorganic particle composite body increases in strength as it
decreases in voidage, and ideally, it preferably has no vacant
spaces. When the shape of the inorganic particles of the inorganic
particle composite body of the present invention is spherical, the
voidage is 30% by volume or less, preferably 10% by volume or less,
more preferably 5% by volume or less, and particularly preferably
1% by volume or less. When the shape of the inorganic particles of
the inorganic particle composite body of the present invention is
layer-form, the voidage is 50% by volume or less, preferably 30% by
volume or less, more preferably 10% by volume or less, particularly
preferably 5% by volume or less, and most preferably 1% by volume
or less.
[0158] In place of the voidage, a volume fraction of a part in
which vacant spaces have been filled with metal, calculated when
the volume of a region where there are inorganic particles is
defined as 100, is represented by V (%), which is used as a measure
of voidage. The larger the V, the less the vacant spaces in an
inorganic particle layer, whereas the smaller the V, the more the
vacant spaces. The range of Vis 0<V<100, preferably
1<V<99, more preferably 10<V<95, and particularly
preferably 50<V<90. Although there is no limitation on the
method of determining V, V can be calculated by the following
method when an inorganic particle structural body composed of a
plate-shaped metal with plasticity and an inorganic particle layer
stacked together has been hybridized to form an inorganic particle
composite body as illustrated in FIG. 24.
[0159] While a region 14 (having a thickness D) of an inorganic
particle composite body, in which inorganic particles are present,
is etched gradually from a surface ds in which inorganic particles
are present to a part de in which there is only metal,
[0160] the amount A (d) of element A derived from the inorganic
particles and the amount B (d) of element B derived from the metal
are measured at several points (for example, five points of ds, d1,
d2, d3, and de in the depth direction). Taking d1, d2, and d3 on an
abscissa and B (d)/A (d) on an ordinate, the depth d0 at which B
(d)/A (d) becomes zero is determined by extrapolation.
V can be expressed by Formula (1) using d0 and D.
V=100.times.(D-d0)/D Formula (1)
[0161] There is no limitation on the means for plastically
deforming the metal. Examples thereof include a method of
pressurizing an inorganic particle structural body and a method of
heating an inorganic particle structural body; these may be used
together. For example, there can be mentioned a method that
comprises heating an inorganic particle structural body to
plastically deform metal and then pressurizing the metal to further
plastically deform, a method that comprises pressurizing an
inorganic particle structural body to plastically deform metal and
then heating the metal to further plastically deform, a method that
comprises performing heating and pressurizing simultaneously to
plastically deform metal in an inorganic particle structural body.
As a method of plastically deforming metal, a method of at least
pressurizing an inorganic particle structural body is preferred.
Examples of the pressurizing method include a pressing method
comprising pressurizing an inorganic particle structural body while
sandwiching it between plates, a roll pressing method by which it
can be pressurized continuously while nipping it between rolls, and
a method comprising applying a static pressure while placing it in
a liquid. The pressure is not limited as far as it is higher than
the atmospheric pressure, and it depends on the degree of the
plasticity of the metal. That is, a low pressure can be used when
softening progresses and a large permanent strain is produced by a
low stress, whereas a high pressure is needed when a high stress is
needed. The pressure is for example 0.1 kgf/cm.sup.2 or more,
preferably 1 kgf/cm.sup.2 or more, more preferably 10 kgf/cm.sup.2
or more, and particularly preferably 100 kgf/cm.sup.2 or more. The
number of times of pressurization is arbitrary and pressurizing
operations under two or more conditions may be combined.
[0162] Examples of the method of heating an inorganic particle
structural body to plastically deform metal include a method
comprising heating the whole of the inorganic particle structural
body, and a method comprising locally heating the metal in the
inorganic particle structural body. Examples of the method of
heating the whole include a method comprising feeding a structural
body into a heating atmosphere using an oven, a heater, or the
like, a method comprising bringing a structural body into contact
with a heat medium, such as a heated metal plate, a method
comprising bringing a structural body into contact with a hot roll
and then pressurizing it, and a method comprising bringing it into
contact with a hot roll, and examples of the method of locally
heating metal include a method comprising heating it by irradiation
with an electromagnetic wave, such as an infrared radiation, a
laser, a microwave, irradiation in a high quantity of light in a
very short time (the flash-annealing method), and radiation, such
as electron beam, and a method comprising keeping only an arbitrary
portion of an inorganic particle structural body into contact with
a heat medium and simultaneously cooling other portion. For metal,
induction heating using a magnetic force line and the
aforementioned irradiation with an electromagnetic wave are
preferably used. The temperature, pressure, and time of pressing
are not particularly limited because they vary depending upon the
property of metal, and conditions suitable for the metal to be
filled into vacant space portions are used. There is no limitation
also on a pressurizing condition and it is determined according to
the property of metal. That is, it is preferred to take conditions
of pressurizing time, pressurizing temperature, pressure and means
of pressurization under and by which inorganic particles
substantially fail to plastically deform and metal plastically
deforms and can fill vacant spaces of an inorganic particle
structural body or an inorganic particle structural body with an
inorganic particle layer stacked. The temperature of heating an
inorganic particle structural body is not particularly limited
because it varies depending upon the property of metal, and
conditions suitable for the metal to be filled into vacant space
portions are used.
[0163] In order to plastically deform metal more easily, auxiliary
means may be added. The auxiliary means referred to herein means a
method of increasing the plasticity of the metal having plasticity.
Examples of the method of increasing the plasticity of metal having
plasticity include a method comprising softening the metal using a
chemical substance and a method comprising increasing the affinity
or the slipping property at the interface of metal and a vacant
space.
[0164] There is no particular limitation on the shape of inorganic
particle composite bodies to be produced by the method of the
present invention and a shape according to a required function and
an intended application is used. Examples thereof include a tabular
shape such as film and sheet, a rod-like shape, a fibrous shape, a
spherical shape, and a three-dimensional structure shape. In the
case that the intended application is a flat-panel display, a
flexible display, or the like, it is preferred that the shape of
the inorganic particle composite body of the present invention also
be a film-like shape. In this case, the thickness of the inorganic
particle composite body, which is not particularly limited, is 100
.mu.m or less, preferably 10 .mu.m or less, more preferably 5 .mu.m
or less, and particularly preferably 1 .mu.m or less. In the case
that flexibility or the like is further required, the thickness of
the inorganic particle composite body is 5 .mu.m or less,
preferably 1 .mu.m or less, more preferably 0.5 .mu.m or less, and
particularly preferably 0.2 .mu.m or less. When the thickness of an
inorganic particle composite body is greater than 100 .mu.m, the
composite body tends to become brittle, whereas when it is 0.01
.mu.m or less, hardness tends to be difficult to develop. It is
also permitted to further stack a resin layer or a metal thin film
on the inorganic particle composite body to be produced by the
method of the present invention. The inorganic particle composite
body of the present invention can develop various properties
depending upon the kind of inorganic particles or metal. When metal
fills vacant spaces of an inorganic particle structural body in a
very high filling ratio, it becomes possible to form an inorganic
particle composite body superior in substance barrier property.
EXAMPLES
[0165] The present invention will be described in detail below with
reference to Examples, to which the present invention is not
limited.
[0166] Main materials used are as follows.
[Inorganic Particle]
[0167] SNOWTEX (registered trademark) ST-XS (colloidal silica
produced by Nissan Chemical Industries, Ltd.; average particle
diameter: 4 to 6 nm; solid concentration: 20% by weight) , which is
hereinafter referred to as "ST-XS."
[0168] Kunipia G (registered trademark) (inorganic layered compound
produced by KUNIMINE INDUSTRIES CO., LTD.; average particle
diameter: 300 nm)
[0169] SNOWTEX (registered trademark) 20 (colloidal silica produced
by Nissan Chemical Industries, Ltd.; average particle diameter: 20
nm; solid concentration: 20% by weight)
[0170] ALUMINASOL (registered trademark) 520 (colloidal alumina
produced by Nissan Chemical Industries, Ltd.; average particle
diameter: 20 nm; solid concentration: 20% by weight)
[0171] Sumecton SA (registered trademark) (inorganic layered
compound produced by KUNIMINE INDUSTRIES CO., LTD.; average
particle diameter: 20 nm)
[Metal]
[0172] Silver particles (silver colloid "MG-101" produced by
[0173] Ishihara Sangyo Kaisha, Ltd.; average particle diameter: 10
nm; solid concentration: 50 wt %)
[Substrate]
[0174] Teonex (registered trademark) (polyethylenenaphthalate film
produced by Teijin DuPont Limited; thickness: 125 .mu.m)
[Coating Liquid A]
[0175] A coating liquid prepared by mixing and stirring MG-101 (3.6
g) in a 3 wt % aqueous solution (12 g) of Kunipia G.
[Coating Liquid B]
[0176] A coating liquid prepared by mixing and stirring MG-101 (0.6
g) in a 3 wt % aqueous solution (4 g) of Kunipia G.
[Coating Liquid C]
[0177] A coating liquid prepared by mixing and stirring ion
exchange water (79.584 g), a 1 wt % Smecton SA solution (9.0 g),
ALUMINASOL 520 (9.000 g) and SNOWTEX 20 (2.4 g), sodium caprylate
(0.014 g), and sodium p-toluenesulfonate (0.002 g).
[Coating Liquid D]
[0178] A coating liquid prepared by mixing and stirring MG101 (4.0
g), ST-XS (4.0 g), and pure water (2.0 g).
[Coating Liquid E]
[0179] A coating liquid prepared by mixing and stirring pure water
(15 g) and glycerol (5.0 g).
[Coating Liquid F]
[0180] A coating liquid prepared by mixing and stirring an
antifouling coating (OPTOOL (registered trademark) DSX; produced by
Daikin Industries, Ltd.) (1.0 g), and fluorine oil (DEMNUM
(registered trademark) SOLVENT; produced by Daikin Industries,
Ltd.) (199.0 g).
[0181] The methods of evaluating properties are as follows.
[Degree of Scratch Resistance]
[0182] Using steel wool (#0000, produced by Nippon Steel Wool Co.,
Ltd.), the surface of an inorganic particle composite body was
rubbed ten strokes under a load of 125 to 500 gf/cm.sup.2 and then
the presence of scratches was checked visually. The case that there
were 10 or less scratches was judged as Level 1, the case that
there were more than 10 but not more than 20 scratches was judged
as Level 2, and the case that there were more than 20 scratches was
judged as Level 3.
[Electron Microscopic Observation]
[0183] Samples were subjected to FIB cutting, and then observation
by a transmission electron microscope (manufactured by Hitachi,
Ltd., model: H900) was carried out for Examples 1, 2, and
Comparative Example 1.
[Oxygen Permeability]
[0184] Oxygen permeability was measured by using an oxygen
permeability analyzer OX-TRAN manufactured by MOCON (measurement
conditions: 23.degree. C., 0% RH).
Example 1
[0185] Coating liquid A was applied to a substrate by using a bar
coater (manufactured by Dai-ichi Rika Co., Ltd., wire gage: #8) and
was dried at 23.degree. C., so that inorganic particle structural
body (1) was obtained. The structural body was sandwiched between a
dielectric heat processor and an iron plate and a weight of 1 kg
was placed thereon. Then, pressurizing treatment was applied with
the portion of MG101 locally heated (dielectric heating conditions:
1000 W, 15 minutes), so that inorganic particle composite body (1)
was obtained. The oxygen permeability of the inorganic particle
structural body (1) was 4 cc/m.sup.2/Day and the oxygen
permeability of the inorganic particle composite body was 0.5
cc/m.sup.2/Day; therefore oxygen barrier property was developed
with a particle film by hybridization. Observation by TEM of a
section of the film confirmed that there was a structure such that
there were inorganic particle portions and metal particles in the
inorganic particle structural body and vacant spaces had been
filled up with metal portions melted and plastically deformed
through local heating and pressurization. When the inorganic
particle composite body (1) was rubbed ten strokes with a wiping
cloth (commercial name: KIMTOWEL produced by NIPPON PAPER CRECIA
Co., LTD.). There was no collapsed composite body. A section of the
inorganic particle composite body (1) is shown in FIG. 25.
Comparative Example 1
[0186] When the inorganic particle structural body (1) was rubbed
ten strokes with KIMTOWEL, part of the structural body collapsed
and the substrate surface was exposed. A sectional TEM photograph
of the inorganic particle structural body (1) is shown in FIG.
26.
Example 2
[0187] Coating liquid B was applied to a substrate by using a bar
coater (manufactured by Dai-ichi Rika Co., Ltd., wire gage: #4) and
was dried at 23.degree. C., so that inorganic particle structural
body (2) was obtained. The thickness of the inorganic particle
structural body is 0.2 .mu.m. The inorganic particle structural
body (2) was preheated at 160.degree. C. for 3 minutes by using a
compression molding machine and then pressed under a certain
condition, i.e., primary compression: at 160.degree. C., 370
kgf/cm.sup.2, for 3 minutes, secondary compression: at 30.degree.
C., 370 kgf/cm.sup.2 for 3 minutes, so that inorganic particle
composite body (2) was obtained. The oxygen permeability of the
inorganic particle structural body (2) was 4 cc/m.sup.2/Day and the
oxygen permeability of the inorganic particle composite body (2)
was 0.9 cc/m.sup.2/Day; therefore oxygen barrier property was
developed with a particle film by hybridization. Observation by TEM
of a section of the film confirmed that there was a structure such
that there were inorganic particle portions and metal particles in
the inorganic layered compound and vacant spaces had been filled up
with metal portions melted and plastically deformed. A sectional
TEM photograph of the inorganic particle composite body (2) of
Example 2 is shown in FIG. 27.
Example 3
[0188] The inorganic particle structural body (1) was subjected to
pressurizing treatment while applying local heating treatment
(dielectric heating conditions: 1400 W, 9 minutes) to silver
portions in the same manner as in Example 1, so that inorganic
particle composite body (3) was obtained. The oxygen permeability
of the inorganic particle composite body (3) was 0.3 cc/m.sup.2/Day
and therefore oxygen barrier property was developed with a particle
film by hybridization. When the inorganic particle composite body
(3) was rubbed ten strokes with KIMTOWEL, no collapse of the
composite body was observed.
Example 4
[0189] Coating liquid C was applied to a support by using a bar
coater (manufactured by Dai-ichi Rika Co., Ltd., wire gage: #4) and
was dried at 23.degree. C., so that inorganic particle structural
body (3) was obtained. Coating liquid D was applied to the
inorganic particle structural body (3) by using a bar coater
(manufactured by Dai-ichi Rika Co., Ltd., wire gage: #1) and was
dried at 23.degree. C., so that inorganic particle structural body
(4) was obtained. The inorganic particle structural body (4)
obtained above was pressed by using a compression molding machine
(manufactured by SHINTO Metal Industries Corporation) under a
certain condition, i.e., primary compression: at 200.degree. C., 70
kgf/cm.sup.2, for 5 minutes, secondary compression: at 30.degree.
C., 70 kgf/cm.sup.2 for 5 minutes, so that inorganic particle
composite body (4) was obtained. The inorganic particle composite
body (4) had a degree of scratch resistance under a 30 g load of
Level 1 and a water contact angle of 29.degree..
Comparative Example 2
[0190] The inorganic particle structural body (4) had a degree of
scratch resistance under a 30 g load of Level 3 and a water contact
angle of 20.degree..
Example 5
[0191] After applying corona treatment to the inorganic particle
composite body (4) , coating liquid E was applied by using a bar
coater (manufactured by Dai-ichi Rika Co., Ltd., wire gage: #1), so
that inorganic particle composite body (5) was obtained. The
inorganic particle composite body (5) had a degree of scratch
resistance under a 30 g load of Level 1 and a water contact angle
of 4.degree..
Example 6
[0192] The inorganic particle composite body (4) was immersed in
coating liquid F and was dried at 23.degree. C. , so that inorganic
particle composite body (6) was obtained. The inorganic particle
composite body (6) obtained above had a degree of scratch
resistance under a 30 g load of Level 1 and a water contact angle
of 103.degree..
INDUSTRIAL APPLICABILITY
[0193] The method of the present invention is superior as a method
for producing a metal-inorganic particle composite body superior in
strength and hardness in which metal having plasticity has been
filled in vacant space portions. It can exhibit various
characteristics depending upon the kinds of the inorganic particles
and the metal. For example, when the metal having plasticity is
metal, such effects as electrical conductivity, paramagnetism,
ferromagnetism, light reflexibility, light absorptivity by plasmon
resonance, rigidity, low linear expansion, ductility, heat
resistance, thermal conductivity, chemistry activity, and/or
catalytic activity are exhibited. Because of this, when an
inorganic particle composite body is formed on a film-shaped
substrate or into a film, it is possible to be applied to
antistatic films, electric conduction films, transparent electric
conduction films, electromagnetic wave shielding films, magnetic
films, reflection films, ultraviolet shielding films, light
diffusing films, antireflection films, antiglare films, hardcoat
films, polarizing films, retardation films, light diffusing films,
front plates of flat panel displays, windows of portable displays
(e.g., cellular phones), films for flexible transparent substrates,
gas barrier films, heat conduction films, heat radiation films,
antibacterial films, catalyst support films, capacitor electrode
films, electrode films of secondary batteries, electrode films of
fuel cells, and so on. Moreover, when the inorganic particles are
made of a clay mineral, the composite body is extremely superior in
substance barrier property due to a maze effect caused by a high
aspect ratio of the clay mineral. For this reason, the inorganic
particle composite body is expected to have properties like those
of transparent metal foil when it has been formed on a film-shaped
substrate or into a film and, therefore, it is particularly useful
for films for flexible transparent substrates, gas barrier films,
transparent electric conduction films, and the like. Because of
superior in hardness, an inorganic particle composite body that is
produced by the method of the present invention is used for optical
information media such as a read only optical disk, an optical
recording disk, and a magneto-optical recording disk, and display
medium members and optical members such as a display screen of a
personal computer, a flexible display, an electronic paper, and a
contact lens for the purpose of preventing a surface from
scratching.
* * * * *