JPH0771630B2 - Multi-layer fine structure - Google Patents

Description

TECHNICAL FIELD The present invention relates to a multi-layer structure fine article in which an adhesive epoxy resin layer is provided on the surface of solid particles, and more specifically, a gap material for a liquid crystal display cell, Gap material for electrochromic display cell, conductive or insulating spacer for electrode plate,
Alternatively, the present invention relates to a film, a sheet, a spacer for maintaining a gap between blocks, a multi-layered fine structure used for forming fine projections on a flat surface or a concave surface for optical and other purposes, for other uses than the above. .

(Prior Art) A case where a multi-layered structure fine material is used as a gap material for a liquid crystal display cell will be described.

Generally, in a liquid crystal display device, since it is necessary to keep a constant gap between two translucent glass substrates or plastic substrates, a gap material for a liquid crystal display cell having a substantially constant diameter is provided between both substrates so that an appropriate gap is maintained. It will be placed in advance.

As conventional gap materials, resin microspheres made of a green polymer having no crosslinked structure, resin microspheres having a crosslinked structure, glass microspheres, or glass short fibers have been proposed. However, since these are not fixed to the substrate, the following problems occur.

In the process of assembling the liquid crystal display cell, when air is blown onto or sucked onto the substrate, the gap material once placed on the substrate scatters and disappears.

Same as above, in the process of injecting liquid crystal into the cell, the gap material moves, and the gap material is unevenly arranged.

While driving the liquid crystal display cell, the gap material moves due to electric and hydrodynamic forces.

Therefore, the gap material arranged between the liquid crystal display cells is required to be fixed to the substrate.

Conventionally, when a resin microsphere made of a linear polymer not having the above-mentioned cross-linking structure is used as a gap material, it becomes impossible to maintain its shape by melting it when heated on a substrate. , Can not be heated. It is also conceivable to coat the surface of solid particles such as resin microspheres, glass microspheres, or glass short fibers having a crosslinked structure that is not easily melted by heating with a resin having adhesiveness to the substrate.

(Problems to be Solved by the Invention) However, when the solid particles are coated with the adhesive resin as described above, there is a drawback that the adhesive resin is easily separated from the surface of the solid particles. In addition, since the wettability between the surface of the solid particles and the adhesive resin is poor, it is necessary to coat the adhesive resin in a relatively large amount, and there is also a drawback that the prepared gap materials aggregate.

The present invention solves the above drawbacks, and its purpose is to:
For example, it is to provide a fine multi-layer structure product that can be adhesively fixed to a substrate in a state where a desired adhesiveness with the substrate is obtained when used as a gap material for a liquid crystal display cell. Another object of the present invention is to provide a fine multi-layer structure product in which the adhesive resin does not separate from the surface of the solid particles and does not aggregate.

(Means for Solving the Problem) The multilayer structure fine product of the present invention has a titanium oxide layer formed by treating an organic titanate compound on the surface of solid particles, and adheres to the surface of the titanium oxide layer. Is provided with a conductive epoxy resin layer, which achieves the above object.

As the material and shape of the solid particles according to the present invention, the following ones can be used.

[Material]

Polyethylene, polypropylene, polymethylpentene,
Linear or crosslinked polymers such as polyvinyl chloride, polytetrafluoroethylene, polystyrene, polymethylmethacrylate, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyimide, polysulfone, polyphenylene oxide, polyacetal; epoxy resin, phenol resin, melamine resin , Unsaturated polyester resin, divinylbenzene polymer, divinylbenzene-styrene copolymer, divinylbenzene-acrylic acid ester copolymer, diallylphthalate polymer, triallyl isocyanurate polymer, benzoguanamine polymer network structure With a resin.

Among the above solid particles, particularly preferred are dizenylbenzene copolymer, divinylbenzene-styrene copolymer, divinylbenzene-acrylic acid ester copolymer,
It is a resin having a network structure such as a diallyl phthalate polymer. As the inorganic material, silicate glass, borosilicate glass, lead glass, soda lime glass, alumina, alumina silicate or the like can be used. Of these,
Particularly preferred are silicate glass and borosilicate glass.

〔shape〕

The shape of the solid particles is not limited, for example,
A spherical shape, an elliptic shape, or a cylindrical shape having the following dimensions can be used.

In the case of spherical solid particles, the diameter should be in the range of 0.1 μm to 1000 μm, and the particularly preferable range is 1 μm to 100 μm.
μm.

In the case of ellipsoidal solid particles, the minor axis is 0.1 μm to 1000 μm
The range is preferably 1 μm to 10 μm.
It is 0 μm. The ratio of the major axis to the minor axis is preferably in the range of 1-10, particularly preferably 1-5.

In the case of cylindrical solid particles, the diameter should be in the range of 0.5 μm to 1000 μm, and the particularly preferable range is 3 μm to 100 μm.
μm. The length-to-diameter ratio of the cylinders should be in the range of 1-50, with a particularly preferred range of 1-10.

[Method of forming titanium oxide layer]

The method of forming the titanium oxide layer on the surface of the solid particles as described above can be performed, for example, by the following method. After applying the organic titanate compound to the surface of the solid particles, the organic titanate compound is hydrolyzed to form a titanium oxide layer.

Examples of the organic titanate compound used here include tetraethoxy titanium Ti (OC ₂ H ₅ ) ₄ , tetrapropoxy titanium Ti (OC ₃ H ₇ ) ₄ , tetrabutoxy titanium Ti (O
C ₄ H ₉ ) ₄ , tetrapentoxytotitanium Ti (OC ₅ H ₁₁ ) ₄ ,
Tetra hexoxyphenyl titanium _{Ti (OC 6 H 13) 4} , tetrakis (2-ethylhexoxy) titanium Ti _{[OCH 2 CH (C 2 H 5} ) C 4
H ₉ ] ₄ , Tetradodecylalkoxy titanium Ti (OC
₁₂ H ₂₅ ) ₄ , tetrastearoxytitanium Ti (OC
₁₇ H ₃₅ ) ₄ , dipropoxy bis (acetylacetonato) titanium Ti (OC ₃ H ₇ ) ₂ [OC. (CH ₃ ) CHCOCH ₃ ] ₂ ,
Dibutoxy bis (triethanolaminat) titanium Ti
(OC ₄ H ₉ ) ₂ [OC ₂ H ₄ N (C ₂ H ₄ OH) ₂ ] ₂ , dividroxy bis (lactato) titanium Ti (OH) ₂ [OCH (CH ₃ ) COO
H] ₂ , titanium propoxythiooctylene glycolate Ti [OCH ₂ CH (C ₂ H ₅ ) CH (C ₃ H ₇ ) OH] _{4 and the} like are used. Among them, tetrapropoxy is particularly preferable. Titanium, tetrabutoxy titanium, tetrakis (2-ethylhexoxy) titanium, dipropoxy bis (acetylacenato) titanium, and dibutoxy bis (triethanolaminato) titanium.

As a method for applying the above-mentioned organic titanate compound to the surface of solid particles, the organic titanate compound is dissolved in a solvent such as n-hexane, cyclohexane, benzene, toluene, trichlene, Freon-113 and the like, and the solid particles are dissolved in the solvent. A method in which the solvent is evaporated and the solvent is evaporated while sufficiently mixing is preferable. After evaporating the solvent, 60 ℃ ~ 100
It is preferable to heat at 0 ° C, but this heating step may be omitted.

It is considered that the organic titanate compound formed on the surface of the solid particles through the above steps reacts with moisture in the air and is hydrolyzed to form, for example, a titanium oxide layer having the following structure. .

[Regarding the Amount of Titanium Oxide Layer] The amount of the titanium oxide layer formed in a thin film on the surface of the solid particles is, in terms of titanium, determined in the range of 0.01 mg to 500 mg per 1 m ² of surface area of the solid particles. Is preferred. A more preferable amount of titanium oxide layer is 0.1 mg to 100 mg.
If the amount of titanium oxide is less than 0.01 mg per 1 m ² of surface area of the solid particles in terms of titanium, the adhesiveness between the solid particles and the adhesive epoxy resin is not exhibited. On the other hand, if the amount of the titanium oxide layer is more than 500 mg per 1 m ² of surface area of the solid particles in terms of titanium, unfavorable results such as a decrease in electric resistance value are brought about.

[Adhesive epoxy resin]

The solid particles having the titanium oxide layer formed on the surface are coated with the adhesive epoxy resin. In the present invention, the adhesive epoxy resin is usually composed of an epoxy resin and a curing agent.

The epoxy resin used in the present invention includes a bisphenol A type epoxy resin (formula I) obtained by reacting bisphenol A with epichlorohydrin, and a bisphenol F type epoxy resin (II) obtained by reacting bisphenol F with epichlorohydrin. Formula), bisphenol
Bisphenol AD type epoxy resin obtained by reaction of AD with epichlorohydrin (formula III), epoxy resin obtained by reaction of bisphenol compound represented by formulas IV to VII with epiclohydrin, phenol novolac type epoxy resin (formula VIII) And cresol volac type epoxy resin (IX type).

In the epoxy resin represented by the above formulas (I) to (IX), n is in the range of 0 to 50, and the preferable range of n is 1
~ 6. When n is 7 or more, the viscosity at the time of heating and melting becomes extremely high, and therefore when the fine particles having a multi-layered structure obtained are placed on a glass plate and heated, the adhesive resin layer is difficult to melt and flow down. There is a problem that it is difficult to obtain the desired adhesiveness. Further, when n is 0, it is liquid at room temperature, or when the viscosity is too low when heated, the adhesive resin layer in the fine multi-layer structure has tackiness or is used on a glass plate. Causes a problem that the adhesive resin layer spreads too much on the plate.

The epoxy resins represented by the above formulas I to IX may be used alone or in combination of two or more. Among the epoxy resins represented by the above formulas I to IX, bisphenol A type epoxy resin (formula I), phenol novolac type epoxy resin (formula VIII) and cresol novolac type epoxy resin (formula IX) are particularly preferable.

In the present invention, the following curing agents are used in combination with the above epoxy resins.

(1) Amine-based curing agent ... Aliphatic amine compounds such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, menthenediamine, isophoronediamine, bis (4-amino-3-methylmicrohexyl) methane; Phenylenediamine, methylenedianiline, benzyldimethylamine, 2-
Aromatic amine compounds such as (dimethylaminomethylphenol) (2) Polyaminoamide-based curing agent ... Ethylenediamine,
A condensation compound of a polyethyleneamine such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenetetramine and an organic carboxylic acid is used as a polyaminoamide-based curing agent. Here, as the organic carboxylic acid, polymerized fatty acid epoxidized unsaturated fatty acid obtained by heat treatment of unsaturated fatty acid such as linoleic acid or linolenic acid, anikenyl succinic acid, and amino acid compound are used.

(3) Acid anhydride curing agent: Dodecenyl succinic anhydride, polyadipic anhydride, phthalic anhydride, methylhexahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, etc. are used as acid anhydride curing agents. To be done.

(4) Basic active hydrogen compound type curing agent: dicyandiamide, adipic acid dihydrazide, eicosane diacid dihydrazide, 7,11-octadecadiene-1,18-dicarbohydrazide, 1,3-bis (hydrazinocarboethyl) -5-Isopropylhydantoin and the like are used.

(5) Imidazole-based curing agent 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-n-alkylimidazole, 2-phenylimidazole, 2-phenyl-2-methylimidazole, 2-ethylimidazole, 1-
Cyanoethyl-2-methyl-imidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2,4-diamino-6- (2'-methylimidazolyl) ethyl-1,3,5
-Triazine, 2,4-diamino-6- (2'-ethyl-4'-
Methylimidazolyl) ethyl-1,3,5-triazine, 2,4
-Diamino-6- (2'-n-undecylimidazolyl)
Ethyl-1,3,5-triazine, 2-phenylimidazole-4,5-diyldimethanol, (5-methyl-2-phenyl-4-imidazolyl) methanol and the like are used as the imidazole-based curing agent.

(6) Tertiary amine curing agent: Tris (dimethylaminomethyl) phenol, dimethylbenzylamine, 1,8-diazabicyclo (5,4,0) undecane, etc. are used as the tertiary amine curing agent.

(7) Others Lewis acid salts such as monoethylamine salt of boron trifluoride, piperidine salt of boron trifluoride, monoethylamine salt of trifluoromethanesulfonic acid, diphenyliodonium salt of hexafluorohisoic acid, and Bronsted acid salt Etc. are used as a curing agent.

The above-mentioned curing agents (1) to (7) are directly mixed with an epoxy resin or used in a microencapsulated form. These are heated in a state of being mixed with an epoxy resin to cause a curing reaction. The heating temperature that causes curing varies depending on the type of curing agent, but is in the range of 50 ° C to 250 ° C. A particularly preferred range is 90 ° C to 200 ° C or less.

The amount of the curing agent added is 0.5 per 100 parts by weight of the epoxy resin.
It can be used in the range of 100 parts by weight to 100 parts by weight, but a particularly preferred range is 5 parts by weight to 50 parts by weight or less.

Among the above-mentioned ones, particularly preferable as the curing agent that can be used in the present invention are the basic active hydrogen compound-based curing agent (4) and the imidazole-based curing agent (5). When these are mixed with epoxy resin, they have no activity to cause a curing reaction at room temperature, so they have a long pot life and can be stored for a long time, but they should be cured quickly by heating above a certain temperature. You can

Although all of the above-mentioned curing agents are of the heat curing type, the following UV curing agents can be used in the present invention.

(A) Aromatic diazonium salt (B) Aromatic sulfonium salt (C) Aromatic iodonium salt These UV curing agents are 0.1 parts per 100 parts by weight of epoxy resin.
It is preferably used in the range of 10 parts by weight to 10 parts by weight.

[Method of coating adhesive epoxy resin]

After the epoxy resin is dissolved in a solvent such as acetone, tetrahydrofuran, methyl ethyl ketone, benzene, and toluene, solid particles having a titanium oxide layer formed on the surface and a curing agent are added to the solution and mixed and dispersed. Although the amount of the solvent used may be arbitrary, it is preferable that the concentration of the epoxy resin is in the range of 3% by weight to 30% by weight.

The adhesive epoxy resin is coated on the surface of the solid particles to form an adhesive epoxy resin layer by evaporating the solvent by means such as decompression while stirring the solution. Addition of a small amount of precipitant or surfactant that dissolves in but not soluble in epoxy resin can prevent the particles from coalescing and agglomerating with each other due to solvent evaporation. . Water is particularly effective as the precipitant.

[Aspect of Adhesive Epoxy Resin Layer] The thickness of the adhesive epoxy resin layer formed on the surface of the solid particles is preferably in the range of 0.01 μm to 100 μm.

(Example) Below, the Example of this invention is described in detail.

Example 1 Tetrapropoxy titanium (manufactured by Nippon Sozo Co., Ltd., trade name A-1) 0.15 g per 10 g of resin microspheres composed of a divinylbenzene polymer and having an average particle size of 9.90 μm and a standard deviation of 0.36 μm.
Was added to 15 ml of hexane, mixed well with a spatula, and hexane was evaporated. Then, this was thoroughly ground in a mortar to eliminate lumps.

On the other hand, the epoxy resin has an epoxy equivalent of 480 and a softening point of
2 g of solid epoxy (produced by Yuka Shell Epoxy Co., Ltd., trade name Epicoat 1001) at 68 ° C. was added to 40 ml of acetone and dissolved, and then 6 ml of water, 10 g of the above microspheres and 2
Ethyl-4-methylimidazole (Shikoku Chemicals Co., Ltd.)
(Trade name, Cureazole 2E4MZ), 0.4 g, was added and mixed thoroughly, and then acetone was evaporated with stirring. The dried product was ground in a mortar to completely loosen the lump.

The particle size of the multi-layered fine particles thus obtained was measured with a Coulter Counter ZB / C-1000 type particle size measuring device, and the average particle size was 10.32 μm and the standard deviation was 0.46 μm. It was From this result, the thickness of the adhesive epoxy resin layer is
It was found that 0.21 μm was formed on the surface of the resin microspheres. Further, the surface of the multi-layered structure microscopic object was observed by a scanning electron microscope, and it was found that the surface of the resin microsphere was uniformly covered with the epoxy resin layer without gaps.

A spray solution prepared by suspending the fine particles having a multilayer structure in Freon 113 was sprayed from a nozzle onto a glass plate. On the glass plate, the fine particles of the multi-layer structure did not aggregate and showed good single particle dispersibility. After this glass plate was left in a heating furnace at 130 ° C for 20 minutes, the adhesion part of the glass plate and the multi-layered structure microscopic object was observed with a scanning electron microscope at a magnification of 2000 times. As a result, the adhesive epoxy resin layer melted. It was observed that the glass plate and the resin microspheres were sufficiently interposed. or,
After sticking an adhesive tape on the glass plate to which the fine multi-layer structure is adhered and then peeling off the tape three times, the number of particles remaining on the glass plate is counted and the residual ratio of the particles is counted. As a result, it was 0.95, and it was confirmed that the bonding was sufficiently performed.

Example 2 Made of silicate glass, having a particle size of 7.30 μm and a standard deviation of 0.32 μm
0.35 g of tetrabutoxytitanium (manufactured by Nippon Sozo Co., Ltd., trade name B-1) per 10 g of inorganic microspheres having a particle size distribution of
A solution dissolved in 5 ml of hexane was added, mixed well with a spatula, and then hexane was evaporated.

Then, this was thoroughly ground in a mortar to eliminate lumps.

As a curing agent, dicyanamide (Yukaka Shell Epoxy Co., Ltd., trade name DICY-7) 0.2 g and 2-phenylimidazole-4,5-diyldimethanol (Shikoku Chemicals Co., Ltd., trade name 2PHZ) 0.2 g was used.

A multi-layer structure fine product was obtained by the same operation as in Example 1 except for the above.

The particle size of this multi-layer structure fine particle is 7.76 μm, standard deviation is 0.35 μm
It was found that the thickness of the adhesive epoxy resin was 0.23 μm. Further, by spraying in the same manner as in Example 1, it was confirmed that fine particles having a fine multilayer structure were dispersed on the glass plate. After this glass plate was left in a heating furnace at 150 ° C. for 30 minutes, the particle residual ratio obtained by peeling the tape in the same manner as in Example 1 was obtained, and the result was 0.90, confirming that the adhesiveness was good.

Example 3 In Example 1, short glass fibers composed of borosilicate glass as the solid particles and having an average particle size of 9.05 μm and an average length of 45.3 μm were used, and tetrakis (2-ethylhexoxy) was added to 10 g of the glass short fibers. A solution prepared by dissolving 0.3 g of titanium (trade name: TOT manufactured by Nippon Soda Co., Ltd.) in 15 ml of hexane was added, mixed well with a spatula, and then hexane was evaporated. Then, this was thoroughly ground in a mortar to eliminate lumps.

1-Cyanoethyl-2-ethyl-4-methylimidazole as a curing agent (Shikoku Chemicals Co., Ltd., trade name 2E4M
Z-CN) 0.4 g was used.

A multi-layer structure fine product was obtained by the same operation as in Example 1 except for the above.

As a result of observation with a scanning electron microscope, the diameter of the fine multi-layer structure product was 9.40 μm, and the thickness of the adhesive epoxy resin layer was 0.17 μm.
It was found to be 5 μm. In addition, it was confirmed that the fine particles of fine multi-layer structure fine particles were dispersed on the glass plate by the same spraying as in Example 1.

After this glass plate was left in a heating furnace at 110 ° C. for 30 minutes, the particle residual ratio by tape peeling similar to that in Example 1 was calculated to be 1.0, which indicates that peeling of the fine multi-layer structure from the glass plate was not observed at all. I couldn't do it.

(Effect of the Invention) As described above, according to the present invention, since the adhesive epoxy resin layer is provided on the surface of the solid particles, the adhesive epoxy resin layer is heated and melted while keeping a predetermined interval by the solid particles. By doing so, this multi-layered structure fine article can be adhered to the substrate. Therefore, when the multi-layered structure fine article of the present invention is used for a gap material for liquid crystal display cell, for example, the gap material does not scatter or move from the substrate surface, and the gap between the two translucent substrates is prevented. It can be ensured that it is kept almost constant to improve the quality.

Moreover, since the titanium oxide layer having good adhesiveness, which is presumed to be derived from the rough surface structure, etc., is provided on the surface of the solid particles, and the adhesive epoxy resin layer is provided on the surface of the titanium oxide layer, the adhesion is improved. The resin can be formed in a thin film with good adhesiveness. Therefore, it is not necessary to coat the adhesive epoxy resin in a large amount, and there is no fear that the fine particles of the multi-layer structure will aggregate.

Claims (1)

[Claims] 1. A titanium oxide layer obtained by treating an organic titanate compound on the surface of solid particles, and an adhesive epoxy resin layer provided on the surface of the titanium oxide layer. Multi-layered fine structure.