JPH106473A - Screen printing plate and screen printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain printing liquid from flowing out of a squeezee sliding area in screen printing by furnishing liquid stopping dams for printing liquid at both ends of the squeezee sliding area in parallel with the squeezee sliding direction in the squeezee sliding surface. SOLUTION: On the screen printing plate 1, a squeezee sliding area 3 is formed in a state where each outer peripheral part 8 remains to have a constant width in order to enable a portion pressed by a sequeezee to be in close contact which a body to be printed during printing. In this sequeezee sliding area 3, the squeezee slides from a squeezee sliding initiation end 9 through a sequeezee sliding completion end 10. A number of printing liquid through-holes are made in the squeezee sliding area 3, and printing liquid is punt on a body to be printed via these through-holes during the squeezee sliding period. Thus, in such a screen printing plate 1, liquid stopping dams 13 are provided at both the ends 11, 12 of the seqeezee sliding area in parallel with the squeezee sliding direction in the squeezee sliding surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a screen printing plate and a screen printing method using the same.

[0002]

2. Description of the Related Art Screen printing is known as a method of printing a printing liquid such as ink on various printing materials. In this screen printing, as shown in FIG.
Screen printing plate 1 having printing liquid permeation holes called gauze
Is applied to the plate frame 2 with tension, a printing liquid 4 is supplied to one end of a squeegee sliding area 3 on a squeegee sliding surface of the screen printing plate, and then the printing liquid is supplied from one end to the other end. Squeegee 5
To slide the printing liquid over the entire squeegee sliding area while allowing the printing liquid to pass through the printing liquid transmission hole onto the printing medium 6 placed on the lower surface of the screen printing plate. It is done.

Here, usually, the squeegee 5 is provided with a printing liquid return 7, and after one sliding operation, the remaining printing liquid is removed when returning the squeegee 5 to its original end. It is general that the printing liquid is returned to the printing liquid return 7 by being sandwiched between the printing liquid return and the printing liquid return 7 again. As another method, there is a method of double squeegee printing in which a squeegee similar to the squeegee 5 is already mounted in place of the printing liquid return 7 and printing is performed in a reciprocating manner. Therefore, the sliding of the squeegee is repeated many times in one supply of the printing liquid, and a large number of printing materials are printed until the printing liquid is supplied again.

[0004]

However, in such screen printing, when the printing liquid is swept over the entire squeegee sliding area by the sliding of the squeegee, a part of the printing liquid is moved in a direction transverse to the sliding direction of the squeegee. The squeegee slides out of the squeegee sliding area. When the printing liquid flows out of the squeegee sliding area in this manner, in screen printing in which a plurality of printing media are printed by supplying the printing liquid once by repeatedly sliding the squeegee as described above, Unless the outflowing printing liquid is collected again in the squeegee sliding area or the printing liquid is not supplied frequently, it is impossible to print a desired number of printing materials.

When the spacer particles are provided on one of the electrode substrates for adjusting the distance between the electrode substrates in the manufacturing process of the liquid crystal display device, the present inventors first performed screen printing to install the spacer particles. We developed a technology that utilizes it (Japanese Patent Application No. 7-262646). However, a spacer particle dispersion in which spacer particles are dispersed in an organic solvent, which is used as a printing liquid in this technique, is expensive and often has a lower viscosity than ordinary printing inks. The problem described above was apt to occur remarkably, and became a major obstacle. Therefore, in screen printing, when using such a low viscosity of the printing liquid, or when using an expensive printing liquid,
Particularly, it is necessary to strongly suppress the outflow of the printing liquid from the squeegee sliding region, and development of an improved technique has been desired.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of the above problems, and as a result, have found that both ends of a squeegee sliding area on a squeegee sliding surface of a screen printing plate are parallel to the squeegee sliding direction. In addition, the inventors have found that the above-mentioned problems can be solved by providing a printing liquid stopping weir, and have completed the present invention.

That is, according to the present invention, first, there is provided a liquid printing dam at both ends of a squeegee sliding area in a squeegee sliding area parallel to a squeegee sliding direction. Version. Secondly, the present invention also provides a screen printing method characterized by performing screen printing using the screen printing plate.

Hereinafter, the present invention will be described with reference to FIG. 1 which is a perspective view of a screen printing plate as a typical embodiment of the present invention as viewed from above a squeegee sliding surface. In FIG. 1, the squeegee sliding area 3 is formed on the screen printing plate 1 with an outer peripheral edge 8 having a constant width left so that a portion pressed by a squeegee at the time of printing can adhere to a printing medium. ing.
In the squeegee sliding area 3, the squeegee slides from the squeegee sliding start end 9 to the squeegee sliding end end 10. In the squeegee sliding area 3, a large number of printing liquid transmitting holes are formed, and when the squeegee slides, the printing liquid is printed on the printing medium through the holes.

However, the most significant feature of the present invention is that, in the screen printing plate having the above structure, the printing liquid is applied to both ends 11, 12 of the squeegee sliding surface 3 parallel to the squeegee sliding direction on the squeegee sliding surface. That is, the liquid stop weir 13 is provided. Thereby, at the time of printing, the printing liquid which is pushed and spread by the sliding of the squeegee and reaches the both ends 11 and 12 is prevented from flowing outside by the liquid stop weir 13, and the outer peripheral edge 8 is formed. No spill.

Here, as a printing liquid to be subjected to screen printing using the above screen printing plate, those known for screen printing can be used without any limitation. For example, there are evaporative drying type ink, oxidation polymerization type ink, heat curing type ink, ultraviolet curing type ink, two-component reaction type ink and the like. These printing liquids have viscosities that do not permeate behind the printing liquid permeation holes under no printing pressure, generally at operating temperatures, for example, 25
Those having a temperature of 0.1 to 10,000 mPa · s at a temperature of ° C. are preferred.

The screen printing using the screen printing plate of the present invention is a method of providing spacer particles between two opposing surfaces such as between electrode substrates of a liquid crystal display device, wherein at least one of the two surfaces is provided. On the surface of, a spacer particle dispersion liquid obtained by dispersing spacer particles in an organic solvent is screen-printed, the organic solvent is evaporated, and thereafter, the spacer particles are provided between the two surfaces. It is preferably used when carrying out the method. In this case, the spacer particle dispersion in which the spacer particles are dispersed in the organic solvent which is a printing liquid has a viscosity of 3% of the viscosity.
A resin having a relatively low viscosity of about 500 mPa · s is preferably used. In the present invention, the effect is most remarkably exhibited when a printing liquid having such a low viscosity is used.

Here, as the organic solvent, for example, 1
-Octanol, 2-octanol, 2-ethyl-1-
Hexanol, 1-nonanol, 1-decanol, 3,
5,5-trimethyl-1-hexanol, 1-undecanol, 1-dodecanol, 1,2-ethanediol,
1,2-propanediol, 1,3-butanediol,
1,4-butanediol, 1,5-pentanediol, 2
-Butene-1,4-diol, 2-ethyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, glycerin, 1,2,6-hexanetriol, diethylene glycol, triethylene glycol, tetraethylene Alcohols having 3 to 12 carbon atoms such as glycol, dipropylene glycol and 3-chloro-1,2-propanediol are preferably used. Also, a fluoro compound based organic solvent such as hydrofluorocarbon and 2,3-dihydrodecafluoropentane; chlorofluorocarbons such as dichloropentafluoropropane (HCFC-225) and dichlorofluoroethane (HCFC-141b); perfluoropentane and perfluoro Hexane, perfluoroheptane, perfluorooctane, perfluorononane, perfluoromethylcyclohexane, perfluoroperhydrophenanthrene, perfluorodecalin, perfluorotriethylamine, perfluorotripropylamine, perfluorotributylamine, perfluorotripentylamine, perfluorotrihexylamine, perfluoro-N-methyl Morpholine, perfluoro-N-ethylmorpholine, perfluo B-N-propylmorpholine, perfluoro-N-
Perfluoro compound organic solvents such as butyl morpholine, perfluoro-N, N-dimethylcyclohexylamine, perfluoro-2-propyltetrahydrofuran, perfluoro-2-butyltetrahydropyran, and perfluorobutylether are also preferably used.

The above-mentioned organic solvents can be used alone or in combination of two or more. It is also possible to mix a high-viscosity solvent and a low-viscosity solvent to adjust the viscosity so that printing is easy.

As the spacer particles, any material can be used without particular limitation as long as the particles are rigid particles. Preferable examples include crosslinked copolymer particles containing divinylbenzene as a main component, benzoguanamine / melamine / formaldehyde condensate particles, silica particles, and glass particles. These spacer particles are not necessarily spherical, but may be rods such as glass fiber spacers, but preferably spherical particles having a sphericity expressed by the ratio of the major axis to the minor axis of 0.9 or more. It is preferred that Further, it is preferable to use a particle having a particle diameter of 1 to 15 microns and a fluctuation rate of 5% or less. However, in consideration of the finishing accuracy of the hole diameter of the printing plate and the clogging of the spacer particles in the holes, the fluctuation is considered. It is preferable that the ratio is small.

The spacer particles are described in JP-A-5-25.
No. 300, JP-A-6-172669, JP-A-6-172660 and JP-A-6-289402
It is preferable that a thermoplastic resin, preferably a thermoplastic resin having a melting point of 250 ° C. or less, is adhered to a surface as described in JP-A No. 2000-163, etc., or coated. In such spacer particles, after being provided on the surface, by heating at a temperature equal to or higher than the melting point of the thermoplastic resin, the thermoplastic resin can be melted and the spacer particles can be firmly welded to the surface. Become.

Next, in the present invention, the screen printing plate may be any of an elastic or non-elastic mesh or a flat plate. For example, the elastic body includes a mesh formed by knitting a nylon wire, a tetron wire, a stainless steel wire or a plate coated with a photosensitive emulsion, and the inelastic body includes nickel, cobalt, chromium, molybdenum, titanium, gold, There are platinum and stainless steel.

The size is, for example, 150 to 1200 in length.
mm, width 150-1200mm, thickness 10-1000μ
m. In a screen printing plate of such a size, the squeegee sliding region is usually formed so as to occupy 10 to 70% of the area of the screen.
Further, as the shape of the printing liquid transmitting hole, those employed in known screen printing plates can be used without any problem. In particular, a straight or tapered through-hole formed by etching, laser light transmission, electroforming, electroless plating, or the like is suitable as long as the solvent does not reach the back under no printing pressure.

The printing liquid dams provided on these screen printing plates are provided at both ends of the squeegee sliding area, which are parallel to the squeegee sliding direction, so as not to come into contact with the sliding squeegee. It is preferable to avoid contact with the squeegee in order to prevent dust generation and the like. The gap with the squeegee is preferably as narrow as possible, and more preferably within 1 mm.

The shape of the liquid weir is not particularly limited as long as it is a protrusion having a height sufficient to suppress the outflow of the printing liquid from the squeegee sliding area. The projections preferably project perpendicularly to the surface of the screen printing plate. The height varies depending on the supply amount of the printing liquid, but is preferably 0.1 to 100 mm, more preferably 1 to 100 mm.
20 mm. Also, the width of the liquid stop weir is usually
It has a size of 0.1 to 100 mm, preferably 1 to 50 mm. Further, the liquid stop weir is preferably provided at both ends parallel to the squeegee sliding direction over the entire length of the end of the squeegee sliding region, but more preferably, the start and end of the squeegee sliding at the end. 50-100 more each than the end side
It is particularly good to set the length longer by mm. Further, the liquid stop weir may be partially provided at both ends parallel to the squeegee sliding direction.

In the present invention, the material of the liquid dam is not particularly limited, but is preferably a material having resistance to the solvent used in the printing liquid. Generally, polyurethane, methylpentene resin, polycarbonate,
Plastics such as fluororesin, acrylic resin, nylon, polypropylene, polyethylene, ABS resin, polystyrene, vinyl chloride; fluororubber, silicone rubber,
Rubbers such as urethane rubber, acrylic rubber, nitrile rubber, ethylene rubber, propylene rubber, butyl rubber, styrene rubber, butadiene rubber, and natural rubber; nickel, cobalt, chromium, molybdenum, titanium, gold, platinum, iron, aluminum, copper, Adopted from metal alloys and the like. Among these, when the squeegee slides, when the squeegee contact portion of the screen printing plate is pressed down by the pressing, the squeegee comes down following the screen printing plate, and a gap or the like is partially generated between the screen printing plate and the screen printing plate. From the viewpoint of difficulty, it is desirable to be made of flexible plastic or rubber.

In the present invention, the method of installing these liquid weirs at the above-mentioned portions of the screen printing plate may be carried out by any method as long as the liquid weir does not move during screen printing. For example, a method of fixing with an adhesive, an adhesive tape, a screw, a screw, or the like can be used. In addition, as long as it does not move during screen printing as described above, it may be simply placed on the screen printing plate. Further, when the screen printing plate is manufactured, the screen printing plate may be molded integrally with the printing plate.

In the present invention, a specific method for screen printing using the above screen printing plate is not particularly limited, and a known method can be employed. The squeegee is preferably provided with a printing liquid return. Squeegee pressure is 10 to 500 mPa, squeegee hardness is 55 to 8
5 °, squeegee angle 30-90 °, sliding speed 1-5
It is preferably set to 00 mm / sec. In addition, the supply amount of the printing liquid per one time is set to be 0.1 to the area of the squeegee sliding area.
01-100 mg / cm ² , preferably 0.1-10 mg / cm ²
cm ² is preferred. The printing to be applied is not particularly limited. However, as described above, the electrode substrate in an electronic visual display device such as a liquid crystal display device is used as a printing medium, and is applied to screen printing when spacer particles are installed on the electrode substrate. Is most effective.

[0023]

When screen printing is performed using the screen printing plate of the present invention, the printing liquid is prevented from flowing out of the squeegee sliding area, and the printing is efficiently performed by minimizing the amount of the printing liquid used. can do.

[0024]

EXAMPLES Examples and comparative examples will be shown below to explain the present invention in detail, but the present invention is not limited to these examples. The test results in Examples and Comparative Examples are values measured according to the following criteria. -Spacer particle printing rate on glass substrate After the printing liquid was screen-printed using a predetermined screen printing plate, the glass substrate on which the solvent was evaporated was observed with a microscope. The measurement was performed by randomly determining 25 locations on a glass substrate, selecting 100 printing points arbitrarily out of tens of thousands of printing points, and calculating the average value of the ratio of one printed point spacer particle printed on the spacer. The particle printing rate was used.

Example 1 A screen printing plate having the structure shown in FIG. 1 was mounted on the screen printing apparatus shown in FIG. 2, and screen printing was performed on a glass substrate 6. The size of the liquid stop weir 14 is 10 mm in height, 20 mm in width, and 450 mm in length.
And 60 mm longer than the end 13), and the material is polyurethane, and the ends of the squeegee sliding area that are parallel to the squeegee sliding direction are 0.5 mm so as not to contact the sliding squeegee. And fixed with adhesive tape. As a printing liquid, 1,2-propanediol (viscosity of 56 mPa · s at 25 ° C.) and 25 μm of 9 μm-diameter true spherical plastic (trade name: Eposter GP-H90, manufactured by Nippon Shokubai Co., Ltd.) as spacer particles were used. %
What was adjusted by mixing and dispersing uniformly so as to be used was used. The obtained printing liquid was screen-printed on the glass substrate. The screen printing plate used is made of nickel,
It has a thickness of 330 mm × 230 mm × 20 μm, the diameter of the upper opening is 50 μm, and the diameter of the lower opening is 15 μm.
1 μm tapered printing liquid transmission holes 11
It is perforated at a density of 50 holes / mm 2, and further has a recess having a diameter of 40 μm and a depth of 20 μm around the opening on the lower surface.

The squeegee pressure in screen printing is 1.
0 kg / 250 mm, squeegee hardness was 70 °, squeegee angle was 70 °, sliding speed was 100 mm / sec, and operation was performed at 25 ° C. Thereafter, the screen printing plate was removed, the glass substrate on which the printing liquid was screen-printed was placed on a hot plate, and the solvent was completely evaporated to obtain a glass substrate on which spacer particles were provided. The supply amount of the printing liquid was set to 15 g, and the glass substrate was continuously printed by supplying such a single amount of the printing liquid, and the printing ratio of the spacer particles was 95%.
The number of glass substrates printed as described above was measured. Table 1 shows the above results.

Example 2 A glass substrate was prepared in the same manner as in Example 1 except that the solvent of the printing liquid was changed to 1,3-butanediol (viscosity at 25 ° C .: 130.3 mPa · s). Obtained. The results are shown in Table 1.

Example 3 In Example 1, the solvent of the printing liquid was changed to 2-ethyl-1,3
Hexanediol (viscosity at 25 ° C. 323 mPa ·
A glass substrate was obtained in the same manner as in Example 1 except that s) was used instead. The results are shown in Table 1.

Comparative Example 1 A glass substrate was obtained in the same manner as in Example 1 except that no liquid stop was provided on the screen printing plate. The results are shown in Table 1.

Comparative Example 2 A glass substrate was obtained in the same manner as in Example 2, except that no liquid stop was provided on the screen printing plate. The results are shown in Table 1.

Comparative Example 3 A glass substrate was obtained in the same manner as in Example 3 except that no liquid stop was provided on the screen printing plate. The results are shown in Table 1.

[0032]

[Table 1]

[0033]

[Brief description of the drawings]

FIG. 1 is a perspective view of a screen printing plate as a typical embodiment of the present invention as viewed from above a squeegee sliding surface.

FIG. 2 is a schematic view showing a state of normal screen printing.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 screen printing plate 2 plate frame 3 squeegee sliding area 4 printing liquid 5 squeegee 6 printing medium 7 printing liquid return 8 outer peripheral edge 9 squeegee sliding start end 10 squeegee sliding end 11 end parallel to squeegee sliding direction 12 End parallel to squeegee sliding direction 13 Liquid weir

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroyuki Mishima 1-1, Mikage-cho, Tokuyama-shi, Yamaguchi Pref. Inside the corporation

Claims (2)

[Claims] 1. A screen printing plate comprising a squeegee sliding surface and a squeegee sliding area on both ends of the squeegee sliding surface parallel to the squeegee sliding direction. 2. A screen printing method using the screen printing plate according to claim 1 for screen printing.