WO2006006612A1

WO2006006612A1 - Method for forming spacer, spacer and display element

Info

Publication number: WO2006006612A1
Application number: PCT/JP2005/012877
Authority: WO
Inventors: Shigekazu Teranishi; Michio Doi; Yutaka Sakai; Koji Tanabe
Original assignee: Natoco Co., Ltd.
Priority date: 2004-07-09
Filing date: 2005-07-06
Publication date: 2006-01-19
Also published as: KR100938165B1; KR20070029738A; TW200624963A; CN100529920C; CN1997933A; JPWO2006006612A1

Abstract

A method for printing and forming a structure of resin and spacer particles on a substrate by a plate-type printing method employing an intaglio, in which the ratio of a resin structure where the spacer particle does not exist is reduced and variation in height of the structure is reduced. A structure containing spacer particles (27) and resin (26) is formed on a substrate (20) by printing ink (24) containing the spacer particles (27) and resin (26) on the substrate (20) by a plate-type printing method employing an intaglio. Aperture diameter W of a recess (19) in the intaglio is 2.1-9.0 times as large as the particle size D of the spacer particles (27) and the depth K of the recess (19) in the intaglio is 0.85-1.7 times as large as the particle size D of the spacer particles (27).

Description

Specification

Spacer forming method, spacer and display element TECHNICAL FIELD

The present invention relates to a spacer forming method used for a liquid crystal display panel or the like, a spacer, and a display element.

Background art

Japanese Patent Application Laid-Open No. 2000-35582 discloses a spacer forming method by gravure offset printing. Claims 2 and 3 of Japanese Patent Application Laid-Open No. 2000-35582 use an ink in which 20 to 60% by weight of a spherical spacer is blended in a resin having a viscosity of 200 to 250 cps. In the examples, 5 // resin spacer particles and polyester resin are shown. Furthermore, it is described that the spacer particles are spherical, the cell opening diameter of the intaglio is 1 to 2 times the spacer particle size, and the cell depth of the intaglio is 0.5 to 2 times the particle size. Yes. Disclosure of the invention

Based on this disclosure, the present inventor made the spacer particles spherical, the cell opening diameter of the intaglio was 1 to 2 times the spacer particle diameter, and the cell depth of the intaglio was 0.5 to 2 times the particle diameter. The spacers were gravure offset printed on the substrate. However, as a result, a large number of resin-only structures containing no spacer particles were present on the printed substrate. A resin-only structure that does not contain spacer particles does not have a gap control function as the originally planned spacer. Therefore, if there are a large number of resin-only structures that do not contain spacer particles, the substrate spacing cannot be maintained uniformly, and display unevenness is likely to occur. In addition, according to the method described in Japanese Patent Application Laid-Open No. 2000-35582, after supplying ink onto the intaglio, the ink is scraped off with a scraping blade. However, at this time, if the cell depth of the intaglio is close to 0.5 times the spacer particle diameter, the spacer particles that have entered the recess are scraped off by the ink scraping blade. In some cases, spacer particles did not remain in the recess. Or, even if the spacer particles remain in the recess, the spacer particles move in the recess toward the moving direction of the scraping blade, and only in one direction in the recess. There was sometimes a bias. As a result, there are a large number of resin-only structures that do not contain spacer particles on the printed substrate, or spacer particles are biased only partially in the structure. For this reason, the original gap-up control function of the spacer could not be demonstrated.

Alternatively, when the indentation depth of the intaglio plate was close to twice the particle diameter of the spacer, the spacer particles sometimes accumulated in the recess after scraping off excess ink with the ink scraping blade. In other words, spacer particles were stacked in each structure, and particles that did not touch the substrate were observed. In this case as well, the proper gap cannot be maintained over the entire surface of the printed board, resulting in gap unevenness and display unevenness.

An object of the present invention is to reduce the proportion of resin structures in which spacer particles are not present in a method of printing and forming a structure of resin and spacer particles on a substrate by a plate-type printing method using an intaglio. It is also to reduce the variation in the height of each structure. ·

The present invention forms a structure containing spacer particles and a resin on a substrate by printing an ink containing spacer particles and a resin on the substrate by a plate printing method using an intaglio. The indentation opening diameter of the intaglio is 2.;! To 9.0 times the particle diameter of the spacer particles, and the indentation depth of the intaglio is It is characterized by being 0.85 to 1.7 times the particle diameter of the spacer particles. The present invention also relates to a spacer, wherein the spacer is formed on the substrate by the method. Furthermore, the present invention relates to a display element characterized by having this spacer.

Contrary to the disclosure of Japanese Laid-Open Patent Publication No. 2000-35582, the present inventor increased the diameter of the concave opening of the intaglio plate to 2.1 times or more of the particle diameter of the spacer particles, so that We have found that the ratio of resin-only structures that do not contain spacer particles can be significantly reduced, and that the gap control function required to maintain a uniform substrate spacing can be fulfilled.

From this point of view, the concave opening diameter of the intaglio is preferably 2.2 times or more of the particle diameter of the spacer particles, more preferably 2.7 times or more,

4.2 Most preferably, it is 2 times or more.

Here, the upper limit of the recess opening diameter of the intaglio is not more than 9.0 times the particle diameter of the spacer particles. If this exceeds 9.0 times, the number of spacer particles entering the recesses will be too large, and it will be difficult to maintain the shape during transfer, resulting in particle stacking and inability to contact the substrate. Particles are generated, and gap unevenness due to structures tends to occur.

It has also been found that the indentation depth of the intaglio must be between 0.85 and 1.7 times the particle size of the spacer particles. By setting the cell depth of the intaglio to 0.85 times or more (preferably 1.0 times or more) of the spacer particle diameter, a resin-only structure without spacer particles on the printed substrate In addition, the unevenness of the spacer particles in the structure can be prevented. The height of the structure can be made uniform by setting the indentation depth of the intaglio to be 1.7 times or less of the spacer particle diameter. Brief Description of Drawings FIG. 1 is a schematic diagram showing a printing apparatus that can be used for the Sgreen printing method. FIG. 2 is a schematic diagram showing the transfer of the ink 24 onto the substrate 20.

Fig. 3 is a diagram schematically showing each process of screen printing.

FIG. 4 is a schematic diagram showing a state where the ink on the intaglio is scratched by the blade 2.

FIG. 5 is a plan view schematically showing the structure 29 on the substrate 20. BEST MODE FOR CARRYING OUT THE INVENTION

The plate-type printing ink used in the present invention includes spacer particles and a thermosetting resin composition in which the spacer particles are dispersed. If necessary, it contains a solvent, a viscosity modifier and other additives. Each of these elements will be described in turn.

(Plate printing method)

This means a printing method using intaglio, and intaglio printing or gravure printing (transfer method, offset method, pad method) can be exemplified.

(Spacer particles)

The material of the spacer particles is not particularly limited, and examples thereof include resins, organic substances, inorganic substances, and compounds and mixtures thereof. The resin is not particularly limited. For example, polyethylene, polypropylene, polymethylpentene, polychlorinated vinyl, polytetrafluoroethylene, polystyrene, polymethyl methacrylate, polyethylene terephthalate, polypropylene terephthalate. , Polyamide, Polyimide, Polysulfone, Polyphenylene oxide, Polyacetal and other linear or cross-linked polymer; Epoxy resin, phenol resin, melamine resin, benzoguanamine resin, unsaturated polyester resin, divinylbenzene heavy , Divinylbenzene-styrene copolymer, divinylbenzene-acrylic acid ester copolymer, Examples thereof include resins having a bridge structure such as diallyl phthalate polymer and triallyl isocyanurate polymer.

Further, the coating material of the spacer particles is not particularly limited, and examples thereof include resins and low melting point metals. Examples of the resin include, but are not limited to, for example, polyolefins such as polyethylene, ethylene / vinyl acetate copolymer, and ethylene / acrylic acid ester copolymer; polymethyl (meth) acrylate, polyethyl (meth) alkyl. (Meth) acrylate polymers or copolymers such as relate, polybutyl (meth) acrylate; polystyrene, styrene / acrylic acid ester copolymer, SB type styrene / butylene block copolymer, SBS type styrene / Butadiene block copolymers, block polymers such as these water additives, thermoplastic resins such as vinyl polymers or copolymers, thermosetting resins such as epoxy resins, phenol resins, melamine resins, mixtures thereof, etc. But it ’s not just physically attached, it ’s chemically bonded. Preference is.

In a preferred embodiment, in the spacer particle, the particle surface and the polymer constituting the adhesive layer are bonded by a covalent bond. Examples of the method include a graft polymerization method and a polymer reaction method. In the graft polymerization method, a polymerizable vinyl group is introduced into the particle surface, the monomer is polymerized starting from the vinyl group, a polymerization initiator is introduced into the particle surface, and the initiator is used. Two methods for polymerizing the above monomers are conceivable. (Resin)

Resins that can be used in the present invention are not limited. Polyester resin, acrylic resin, epoxy resin, reaction product of polyester resin and acid anhydride, lactone-modified phenoxy resin, lactone-modified butyral, vinyl resin, phenol Examples thereof include resins and melamine resins.

(solvent) The plate-type printing ink of the present invention may contain a solvent.

The following can be illustrated as this solvent.

(1) Low boiling point solvent with a boiling point of 120 ° C or lower

n-hexane, n-heptane, aliphatic hydrocarbons such as rubber volatile oil, etc .; aromatic hydrocarbons such as cyclohexane, toluene, methylcyclohexane, etc .; methyl alcohol, ethyl alcohol, n_propyl alcohol, isopropanol Alcohols such as pill alcohol, n-butyl alcohol, sec-butyl alcohol, and isobutyl alcohol; esters such as methyl acetate, ethyl acetate, isopropyl acetate, and n-propyl acetate; acetone, methyl ethyl ketone, methyl isobutyl ketone, etc. Ketones.

(2) Boiling point 1 2 0 ~ 2 30 ° C medium boiling solvent

Aliphatic hydrocarbons such as mineral spirits; aromatic hydrocarbons such as xylene, solvent naphtha, tetralin and dipentene; alcohols such as cyclohexyl alcohol and 2-methylcyclohexyl alcohol; esters such as butylacetate; Hexanone, methylcyclohexanone, diacetone alcohol, ketone such as isophorone, glycol such as ethylene glycol, propylene glycol, etc .; Ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene Glycol ethers such as glycol monobutyl ether; ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol Over monomethyl E chill ether § cetearyl one bets like glycol ethers Es ether

(3) High boiling point solvent with boiling point of 2 30 to 3 20 ° C

Aliphatic hydrocarbons such as ink oil; alcohols such as tridecyl alcohol; diethylene glycol, triethylene glycol, dipropylene Glycol such as glycol; glycol ether such as jetylene glycol monobutyl ether; glycol ether ester such as diethylene glycol monobutyl ether acetate

Examples of these solvents are listed in Table 2.8 on page 43, for example, “Introduction to Printing Ink Supplement” (Jiro Aihara, Printing Society Press).

In addition, a viscosity modifier may be used for the ink of the present invention in order to adjust the ink viscosity to be suitable for printing. For example, as an example of a viscosity modifier, ultra fine silica (for example, Nippon Aerosil Co., Ltd., trade name Aerosil, Mizusawa Chemical Co., Ltd., trade name Mizukasil, Fuji Sirisya Chemical Co., Ltd., trade name Silica, Silo Hovic, Fuso Chemical Industry) Trade names such as Quo Tron Co., Ltd.).

The plate-type printing ink of the present invention can be used to form a spacer on a glass substrate for a liquid crystal panel by a printing method disclosed in JP-A-2000-35582. It is desirable to mix the spacer particles in the resin by 20 to 60% by weight. From the standpoint of suitability and printing accuracy for the silicone blanket used in this printing method, as a solvent, an alcohol having 11 or more carbon atoms (for example, trade name “Dianal” manufactured by Mitsubishi Chemical Corporation), boiling point 1 2 0 An aliphatic hydrocarbon solvent having a boiling point of 120 ° C or higher and an aromatic hydrocarbon solvent having a boiling point of 120 ° C or higher are preferred (reference: Jiro Aihara, Printing Printing Introductory Edition).

This preferred printing method will be mainly described.

Preferably, when supplying ink to the plate, two blades are used: an ink supply blade for the intaglio plate and an ink contact blade. When transferring the resin from the surface of the intaglio to the filter substrate, a silicon bracket is used as the transfer sheet. In addition to the silicon bracket, a resin relief printing plate may be used as the transfer sheet. In the printing machine schematically shown in Fig. 1, the main body frame 10 is provided with a height-adjustable printing plate surface plate 1 1 provided with an intaglio 9 and a work surface plate 1 2 provided with a filter substrate 2 0. . A bogie frame 13 is provided on the main body frame 10.

The dolly frame 1 3 moves on each surface plate. A transfer cylinder 1 4 is supported on the carriage frame 1 3 and can be moved up and down. The transfer sheet 3 is mounted on the outer peripheral surface of the transfer cylinder 14. The carriage frame 13 is provided with an ink supply device 15, an ink supply blade 1 that is supported and fixed to an elevating air cylinder 1, and an ink removing blade 2.

The method for producing the printing intaglio 9 is not particularly limited, and can be produced by a known etching method. The recess opening width of the intaglio can be controlled by controlling the opening width of the exposure mask. The depth of the recess can be controlled by selecting the opening width, etching time and material.

The manufacturing method will be described with reference to FIGS. As shown in Fig. 2, set the intaglio 9 on the printing platen 11 and attach the silicon blanket 3 to the transfer cylinder 14. Ink 2 4 is dropped on the intaglio 9 from the ink supply device 1 5 (Fig. 3a). Scatter the excess ink with the ink scraper blade 2 while smoothing the ink with the ink supply blade 1 while moving the carriage frame 1 3 (mouth), transfer the transfer cylinder 1 4 onto the intaglio 9 and transfer the ink 2 4 Transfer to the third side of the sheet (C) and transfer the ink on the third side of the transfer sheet to the 20th side of the substrate (2). 2 2 is a non-pixel portion.

Here, for example, as shown in FIG. 4, by increasing the opening diameter W of the recesses 19 of the intaglio plate to be 2.1 times or more the particle diameter D of the spacer particles, a certain number of the recesses 19 are obtained. As a result, the proportion of resin-only structures that do not contain spacer particles can be significantly reduced on the printed circuit board. The opening diameter W of the intaglio depression 9 is the particle diameter D of the spacer particle 2. By making it 7 times or more, the ratio of the resin-free structure containing only the spacer particles can be made 10% or less.

As shown in FIG. 5, according to the present invention, a large number of resin structures 29 including a resin 30 and a predetermined number of spacer particles 27 can be printed and transferred on a substrate 20. Is possible. In other words, the proportion of the resin structure not including the spacer particles 27 can be reduced to, for example, 30% or less, further 10% or less.

However, if the concave opening diameter W of the intaglio increases and exceeds 9.0 times the particle diameter D of the spacer particles, the number of spacer particles 2 7 that enter the concave portion 19 becomes too large, and the transfer Sometimes it becomes difficult to maintain the shape, and the accumulation of particles occurs, or particles that cannot contact the substrate are generated, and the gap unevenness due to the structure is likely to occur.

In addition, if the cell depth K of the intaglio is less than 0.85 times the spacer particle diameter D, when the excess ink 24 on the intaglio 9 is scraped off by the blade 2, it does not enter the recess. Along with the spacer particles 2 8, the particles 2 7 contained in the recesses to some extent are also easily scraped off. As a result, it was found that many resin-only structures without spacer particles are likely to occur on the printed substrate.

In addition, when the indentation depth K of the intaglio exceeds 1.7 times the spacer particle diameter D, the spacer particles are likely to enter the recess in a state where two or more stages are stacked. It has been found that when the spacer particles are stacked in the recess 19, the spacer particles overlap in the structure, resulting in a variation in the height of the structure. Such a problem can be solved by the present invention.

As described above, according to the present invention, as shown in FIG. 5, a large number of resin structures 29 including resin 30 and a predetermined number of spacer particles 27 are printed and transferred on a substrate 20. Is possible. Example

Crosslinked polymer particles (a) and a resin composition (liquid) (b) were mixed to prepare an ink. The proportion of the crosslinked polymer particles (a) in the total ink was set to 25% by weight.

In this example, the crosslinked polymer particles (a) were prepared as described in JP-A No. 2 03-3-1 1 7 5 4 6.

In other words, a 2 L separable flask was charged with 400 g of polyvinylpyrrolidone 3.5% methanol solution, 42 g of styrene, 63 g of p-trimethylsilylstyrene, and gently stirred under a nitrogen stream. While heating to 60 ° C. Add 4 g of azobisisoptylonitrile and allow to react for 12 hours. After completion of the reaction, the mixture was cooled to room temperature, and 20 g of a 5% aqueous solution of potassium hydroxide was added, followed by stirring at 60 ° C. for 2 hours for hydrolysis and crosslinking reaction. The obtained particles were washed to obtain particles A. To 20 g of particle A, add 20 g of toluene solution in which 10 g of interpenetrating polymer network-forming compound (2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane) is dissolved. Epoxy was impregnated. Subsequently, the epoxy-impregnated particles were heated at 200 ° C. for 16 hours and then washed to obtain crosslinked polymer particles B having a hydroxyl group derived from an epoxy group on the particle surface 4a. The average particle size of particles B was 4.2 mm, and the coefficient of variation was 3%.

The resin composition was prepared as follows.

“Placcel 4 1 0 D” (Poly-Strength Prolacton Tetraol, manufactured by Daicel Chemical Industries, Ltd.) 4 5 parts by weight, carboxylic acid-containing poly-strength triol (poly-strength prolacton triol and tetrahydrofuran phthalic anhydride) And 1: 1 molar ratio adduct) 20 parts by weight, "Cymel 300" (Melamine resin, Mitsui Cytec Co., Ltd.) 3 5 parts by weight, "Dianar 1 3 5" (dissolved) Medium: Higher alcohol mixture having 13 and 15 carbon atoms (Mitsubishi Chemical Co., Ltd.) 25 parts by weight were mixed and reacted at 120 to 125 ° C for 6 to 7 hours. Furthermore, 100 parts by weight of the above resin solution (total amount), “Aerosil 3 00 CF” (viscosity modifier: porous silica, manufactured by Nippon Aerosil Co., Ltd.) 1 2 parts by weight, “Dianar 1 3 5 ”(Solvent) 2 5 parts by weight were premixed and dispersed with a roll to obtain an ink resin composition.

The intaglio was produced by the method described in Examples of JP 2000-35582 A, using a glass intaglio. The shape of the recess was a cylindrical shape, and the recess opening diameter and opening depth were changed as shown in Table 1. For the opening diameter and depth of the recess, an ultra-deep color 3D shape measurement microscope “V K- 9 5 0 0” manufactured by Keyence Corporation was used. The openings were arranged in a lattice pattern.

Printing was performed as described above. However, a silicon blanket was used. After the ink was transferred and printed on the intaglio, it was dried at 220 ° C. for 1 hour in order to cure the ink. After the ink was transferred and printed on the substrate, the number of spacer particles in the ink transferred from one recess was observed with an optical microscope. For each example, data corresponding to 200 recesses was taken, and the average value of the number of particles in the structure and the abundance ratio of the locations where no particles exist are shown in Table 1.

In addition, for the uniformity of the height of the structure, 10 structures 29 having a large number of particles were arbitrarily selected, and the height of the structure 29 was measured. For this measurement, an ultra-deep color 3D shape measuring microscope “V K-9500” manufactured by Kiensence Co., Ltd. was used.

(Criteria for arrangement efficiency of structure 29)

◎: The presence rate of the part where particles are not present is 10% or less

○: The existence rate of the part where particles are not present is 10 to 30%

X: The presence rate of the part where particles are not present is 30% or more (Criteria for uniformity of height of structure 29)

○: The structure 29 whose height is 1.8 times the particle diameter or more could not be confirmed.

X: Structure 29 having a height of 1.8 times or more of the particle diameter was confirmed.

Table 1 Examples Examples Examples Examples Examples 1 2 3 4 5 Particle size used 4.2 3 1. 4. 8 5. 1 4. 4

(m) Concave opening diameter 2 5 2 5 2 5 2 5 1 5 (m) Concave depth-5 5 5 5 5.5

Concave opening diameter / 5.96 8.19 5.20 4.94 3.41 Used particle diameter Concave opening depth / 1.19 1.64 1.04 0.99 1.25 Used particle diameter Average number of particles 5.4 11.8 3. 5 3. 0 2. 0 Presence of particles No 0. 0 0, 0 1. 5 12.0 4. 0 Location rate

(%) Structure 2 9 ◎ ◎ ◎ ○ ◎ Placement efficiency Structure 2 9 ○ ○ ○ ○ ○ Uniformity of height Table 2

In Examples 2, 3, 4, 5, 6, and 7, the indentation opening diameter of the intaglio was set to 2.1 to 9.0 times the particle diameter of the spacer particle, and the indentation indentation depth was set to the spacer particle. The particle size of 0.85 to 1.7 times the particle size of the spacer particles The ratio of non-existing resin structures can be reduced, and the variation in height of each structure can be reduced. In Comparative Example 1, the indentation depth of the intaglio is 0.83 times the particle diameter of the spacer particles, but the proportion of the resin structure without the spacer particles is high. There are large variations in the height of structures. In Comparative Example 3, the recess opening diameter of the intaglio is set to 1.67 times the particle diameter of the spacer particles, but the arrangement efficiency of the structure 29 is low.

Although specific embodiments of the present invention have been described, the present invention is not limited to these specific embodiments and can be implemented with various changes and modifications without departing from the scope of the claims. .

Claims

The scope of the claims

1. A structure containing the spacer particles and the resin is formed on the substrate by printing the ink containing the spacer particles and the resin on the substrate using an intaglio plate by a plate-type printing method. A way to

The concave opening diameter of the intaglio is 2.1 to 9.0 times the particle diameter of the spacer particles, and the concave depth of the intaglio is 0.85 to 1.7 of the particle diameter of the spacer particles. Spacer forming method characterized by being doubled.

2. The method according to claim 1, wherein the concave opening diameter of the intaglio is at least 4.2 times the particle diameter of the spacer particles.

3. On the substrate, the spacer particles with respect to the total number of the structure including the spacer particles and the resin and the structure including the spacer particles and not including the spacer particles. The method according to claim 1 or 2, wherein a ratio of the number of the structures made of the resin is 30% or less.

4. A spacer formed on the substrate by the method according to any one of claims 1 to 3.

5. On the substrate, the spacer particles with respect to the total number of the structure including the spacer particles and the resin and the structure including the spacer particles and not including the spacer particles. 5. The spacer according to claim 4, wherein the proportion of the number of structures made of the resin is 30% or less.

6. A genealogy having the spacer according to claim 4 or 5.