JPH0725150B2 - Multi-layer fine structure - Google Patents

Description

TECHNICAL FIELD The present invention relates to a microstructure having a multilayer structure in which a hot-melt type adhesive resin layer is provided on the surface of solid particles, and more specifically, a gap for a liquid crystal display cell. Materials, gap materials for electro-display cells, conductive or insulating spacers for electrode plates, films for other applications than the above, sheets, spacers for maintaining gaps between blocks, flat or concave surfaces for optical and other applications The present invention relates to a multi-layer structure fine article used for forming fine protrusions or the like on top.

(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 the gap between two translucent glass substrates or plastic substrates constant, a gap material for a liquid crystal display cell having a substantially constant diameter is appropriately disposed between both substrates. Will be placed.

As conventional gap materials, resin microspheres made of a linear 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 have occurred.

In the process of assembling the liquid crystal display cell, the gap material once arranged on the substrate scatters and disappears at the time of blowing or sucking air onto the substrate.

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

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 does not melt easily 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 a relatively large amount of the adhesive resin, and since the adhesive resin has tackiness, it is created. There is also the drawback that the gap materials will aggregate. This tendency is particularly remarkable when a polyolefin resin is used as the adhesive resin.

The present invention solves the above drawbacks, and its purpose is to:
For example, when used as a gap material for a liquid crystal display cell, it is to provide a fine multi-layer structure product that can be adhesively fixed to a substrate in a state where desired adhesiveness with the substrate is obtained.
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 Problems) In the multilayer structure fine product of the present invention, a titanium oxide layer obtained by hydrolyzing an organic titanate compound is formed on the surface of solid particles, and the surface of the titanium oxide layer is formed. Is characterized in that a hot-melt type adhesive resin layer is provided in
Thereby, the above object is achieved.

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, polyethyleneterephthalate, polybutyleneterephthalate, polyamide, polyimide, polysulfone, polyphenyleneoxide, polyacetal; epoxy resin, phenolic resin, melamine Network structure of resins, unsaturated polyester resins, divinylbenzene polymers, divinylbenzene-styrene copolymers, divinylbenzene-acrylic acid ester copolymers, diacrylic phthalate polymers, triallyl isocyanurate polymers, benzoguanamine polymers, etc. With a resin.

Among the above solid particles, particularly preferable are resins having a network structure such as divinylbenzene copolymer, divinylbenzene-styrene copolymer, divinylbenzene-acrylic acid ester copolymer, and diacrylic phthalate polymer. is there.

As inorganic materials, silicate glass, borosilicate glass,
Lead glass, soda-lime glass, alumina, alumina silicate or the like can be used. Of these, silicate glass and borosilicate glass are particularly preferable.

〔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.

For solid spherical solid particles, the diameter is 0.1μm to 1000μ
It is preferably in the range of m, and a particularly preferred range is 1 μm to 100 μm.

In the case of ellipsoidal solid particles, the minor axis is 0.1 μm to 1000
The range is preferably μm, and the particularly preferred range is 1 μm.
Or 100 μm. The ratio of major axis to minor axis is 1 to 10
The range of 1 to 5 is particularly preferable, and the range of 1 to 5 is particularly preferable.
Is.

For cylindrical solid particles, the diameter is 0.5μm to 1000μ
The range is preferably m, and the particularly preferred range is 3 μm to 100 μm. Cylinder length to diameter ratio is 1 to 5
A range of 0 is preferable, and a particularly preferable range is 1 to 1.
The range is 0.

[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 T
i (OC ₄ H ₉ ) ₄ , tetrapentoxytitanium Ti (OC
₅ H ₁₁ ) ₄ , tetrahexoxy 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 (triethanolaminato) titanium Ti
(OC ₄ H ₉ ) ₂ [OC ₂ H ₄ N (C ₂ H ₄ OH) ₂ ] ₂ , dihydroxybis (lacto) titanium Ti (OH) ₂ [OCH (CH ₃ ) COO
H] ₂ , titanium propoxyoctylene glycolate Ti [OCH ₂ CH (C ₂ H ₅ ) CH (C ₃ H ₇ ) OH] _{4 and the} like are used. Among them, tetrapropoxy titanium is particularly preferable. Tetrabutoxy titanium, tetrakis (2-ethylhexoxy) titanium, dipropoxy bis (acetylacenato) titanium, and dibutoxy bis (triethanolaminato) titanium.

As a method of 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 is dissolved in the solvent. A method of immersing the particles and evaporating the solvent while mixing them sufficiently is preferable. After evaporating the solvent, it is preferable to heat at 60 ° C to 100 ° C, but this heating step may be omitted.

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

[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 surface area 1 m ² of the solid particles. Is preferred.
A more preferable amount of titanium oxide layer is 0.1 mg to 100 mg.
mg. If the amount of titanium oxide layer is less than 0.01 mg per surface area 1 m ² of the solid particles in terms of titanium equivalent,
Adhesion between the solid particles and the hot melt olefin resin is not exhibited. On the contrary, the amount of the titanium oxide layer is 5 in terms of titanium equivalent weight per 1 m ² of the surface area of the solid particles.
When it is more than 00 mg, it causes unfavorable results such as reduction of electric resistance value.

[Hot melt adhesive resin]

The solid particles having the titanium oxide layer formed on the surface are coated with the hot-melt adhesive resin shown below. Examples of the hot melt type adhesive resin used in the present invention are shown below.

(1) Olefin-based adhesive resin Polyethylene wax, polyethylene wax oxide, low-density polyethylene, high-density polyethylene, polyethylene oxide, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-carbon monoxide three-dimensional copolymer, Ethylene
Acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-vinyl acetate-acrylic acid three-dimensional copolymer and other carboxyl group-containing ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-vinyl alcohol three-dimensional copolymer Polymer, ethylene-oxide ion copolymer, sulfonated polyethylene, ethylene-propyne copolymer, polypropylene, hydrogenated polybutadiene, hydrogenated polyisoprene,
Hydrogenated polybutadiene-styrene block copolymer, hydrogenated polyisoprene-styrene block copolymer and oxides thereof.

(2) Other adhesive resins Polymethyl acrylate, polyethyl acrylate, polybutyl acrylate, polybutadiene, polyisoprene, polyamide, polyurethane, polyester, polyimide, acetalized polyvinyl alcohol, butyralized polyvinyl alcohol, butadiene-styrene random copolymer , Butadiene-styrene block copolymer,
Isoprene-styrene block copolymer and the like.

Among the resins shown in (1) and (2) above, the preferred adhesive resin is the polyolefin shown in (1), and the particularly preferred adhesive resin is polyethylene wax and its oxide, ethylene-vinyl acetate Polymers and their oxides, carboxyl group-containing ethylene vinyl acetate copolymers. Since these resins have relatively low melting points or softening temperatures, they easily melt or soften at relatively low temperatures. Therefore, when the produced fine particles having a multilayer structure are used as, for example, a gap material for a liquid crystal display cell, desired adhesiveness to a substrate is easily obtained. Further, the resin has a low adhesiveness as compared with a resin such as polyamide, but has a low polarity, and therefore has an advantage of not disturbing the alignment of the liquid crystal when the fine multi-layered structure is used as a gap material for a liquid crystal display cell. Have.

The requirement that the hot-melt adhesive resin should have is that it is softened or melted by heating at a temperature lower than the softening temperature and the decomposition temperature of the solid particles.
The desirable softening or melting temperature range of the adhesive resin is 85 ° C to 200 ° C, and the particularly preferred temperature range is 90 ° C to 1 ° C.
70 ° C.

[Coating method of hot melt adhesive resin]

The hot-melt adhesive resin is dissolved in a solvent, the solution is applied to the surface of the solid particles, and then the solvent is evaporated to coat the surface of the solid particles with the hot-melt adhesive resin. You can After coating the hot-melt adhesive resin on the surface of the solid particles, it is preferable to post-crosslink the resin by means such as irradiation with radiation or heating, but this step may be omitted in particular.

[Aspect of Hot Melt Type Adhesive Resin Layer]

The thickness of the hot melt adhesive 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 10.10 μm average particle size composed of divinylbenzene polymer,
For 10 g of resin microspheres having a standard deviation of 0.40 μm, tetrapropoxy titanium (manufactured by Nippon Soda Co., Ltd., product surface A-1)
A solution prepared by dissolving 15 g of n-hexane in 15 ml was added, and the mixture was thoroughly mixed with a spatula, and then n-hexane was evaporated. Then, this product was thoroughly crushed in a mortar to eliminate lumps.

On the other hand, polyethylene wax (manufactured by Sanyo Kasei Co., Ltd., trade name Sun Wax) is used as a hot melt adhesive resin.
(151-P) (2.6 g) was added to toluene (10 cc) and dissolved in a 80 ° C warm bath. The resin microspheres treated with the above organic titanate compound were added to this solution, dispersed until it became completely milky, and then dried by heating at 90 ° C. under a reduced pressure of 300 mmHg.

Thus, the resin microspheres coated with the hot melt type resin are obtained as a lump. Next, 20 ml of glycerin was added to this lump, and the lump was thoroughly crushed in a mortar and passed through a three-roll mill to completely loosen the lump.

Next, this was washed on a glass filter with 1 of ethanol, and then suspended in 1 of an ethanol / Freon 113 mixed solution (volume ratio 2: 1). Then
In this state, the mixture was allowed to stand for 15:00, and the supernatant was decanted to remove fine particles of polyethylene wax. This was filtered again on a glass filter and then washed with Freon 113. This was heated and dried at 60 ° C. in a gear oven to obtain a fine multi-layer structure product.

Coulter counter ZB / C
As a result of measurement with a −1000 type particle size measuring device, the average particle size is
The results were 10.42 μm and standard deviation 0.43 μm. From this result, it was revealed that the polyethylene wax was formed on the surface of the resin microspheres with an average thickness of 0.16 μm. Moreover, as a result of observing the surface of the multi-layered structure fine substance with a scanning electron microscope, it was found that the surface of the resin microsphere was uniformly coated with polyethylene wax 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, each of the fine particles having a multi-layered structure did not aggregate and showed good single particle dispersibility. After this glass plate was left in a heating furnace at 110 ° C for 10 minutes, the adhesion part of the glass plate and the fine multi-layered structure was observed with a magnifying glass of 200 times. As a result, the polyethylene wax layer melted and the polyethylene wax layer was melted. Was sufficiently interposed between the glass plate and the resin microspheres, and it was confirmed that the resin microspheres adhered to the glass plate.

Example 2 Made of silicate glass and having a particle size of 7.30 μm and a standard deviation of 0.32 μm.
Tetrabutoxy titanium (manufactured by Nippon Soda Co., Ltd., trade name B-1) 0.35 for 10 g of inorganic microspheres having a particle size distribution of m.
A solution prepared by dissolving g in 15 ml of n-hexane was added, mixed well with a spatula, and then n-hexane was evaporated. Then, this product was thoroughly crushed in a mortar to eliminate lumps.

On the other hand, as the hot-melt adhesive resin, 2.9 g of a carboxyl group-containing ethylene-vinyl acetate copolymer (Takeda Pharmaceutical Co., Ltd., trade name Dumilan C-2280) 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 7.58 μm, and the standard deviation is 0.
It was found to be 43 μm, and the average thickness of the carboxy group-containing ethylene-vinyl acetate copolymer layer was 0.14 μm. Further, by spraying in the same manner as in Example 1, good single-particle dispersion of fine particles having a multilayer structure was obtained on the glass plate.
It was confirmed that by leaving this glass plate in a heating furnace at 120 ° C. for 10 minutes, good adhesion was brought between the microspheres and the glass plate.

Example 3 In Example 1, short glass fibers made of borosilicate glass having an average diameter of 9.05 μm and an average length of 15.1 μm were used as solid particles, and tetrakis (2-ethylhexoxy) was used for 10 g of the glass short fibers. Titanium (Nippon Soda Co., Ltd.)
A solution prepared by dissolving 0.3 g of trade name TOT) in 15 ml of n-hexane was added, mixed well with a spatula, and then n-hexane was evaporated. Then, this product was thoroughly crushed in a mortar to eliminate lumps.

On the other hand, as the hot melt adhesive resin, 2.5 g of polyethylene wax oxide (Sun Wax E-300 manufactured by Sanyo Chemical Industry Co., Ltd.) 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 particles having a multilayer structure was 9.31 μm. From this result,
It was found that the hot melt adhesive resin layer was formed on the glass short fibers with an average thickness of 0.13 μm.

(Effect of the invention) As described above, according to the present invention, since the hot-melt adhesive resin layer is provided on the surface of the solid particles, the hot-melt adhesive resin is kept at a predetermined interval by the solid particles. By heating and melting the layer, the fine particles having a multilayer structure can be adhered to the substrate. Therefore, when the multi-layered structure fine substance of the present invention is used, for example, as a gap material for a liquid crystal display cell, 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, is provided on the surface of the solid particles, and the hot-melt type adhesive resin layer is provided on the surface of the titanium oxide layer. The adhesive resin can be formed in a thin film state with good adhesiveness. Therefore, as the adhesive resin, it is not particularly necessary to use a resin having excellent adhesiveness to solid particles, and a resin having poor polarity such as a polyolefin-based resin can be used. When using it as a gap material for display cells,
The adhesive resin does not cause any problems such as disturbing the alignment of the liquid crystal. Further, it becomes possible to use a resin having a low melting point or a low softening temperature, which can improve the productivity and the adhesion of the gap material to the substrate. Moreover, since the adhesive resin has a good leak property with respect to the titanium oxide layer, it suffices to coat only a monomolecular layer of the adhesive resin, and there is no fear that the fine particles having a multilayer structure will aggregate.

Claims (1)

[Claims] 1. A titanium oxide layer obtained by hydrolyzing an organic titanate compound is formed on the surface of solid particles, and a hot-melt adhesive resin layer is provided on the surface of the titanium oxide layer. Fine multi-layered structure characterized by.