JP2001035366A - Barrier rib forming method of plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve yield by forming a desired sand blast mask through printing a printing paste composed of a hard to grind composition which is containing glass frit, having a softening point lower than that of a barrier rib material as a component on the barrier rib material forming a layer, forming the barrier rib material of a desired pattern by grinding the barrier rib material, and fixing/forming a rib on a substrate by baking. SOLUTION: Rib paste 2 composed of an easily grindable composition is formed as a layer in a prescribed thickness on a substrate 1, and printing paste 3 composed of a hard to grind and burnable composition, including glass frit having a softening point lower than a barrier rib material as a component is printed on the barrier rib material for forming a layer. If necessary, hardening processing is performed on the printing paste 3 of a printed desired pattern, by heating and irradiation of ionizing radiation to obtain physical properties as a sand blast mask 3. Next, after performing sand blast processing, a rib 6 is fixed/formed on the glass substrate 1 by baking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention belongs to the technical field of manufacturing a plasma display panel. In particular, the present invention relates to a method for forming a partition for forming a discharge space on a plasma display substrate.

[0002]

2. Description of the Related Art A sand blast method is known as a method for forming a partition on a plasma display substrate.
FIG. 4 shows a pictorial diagram relating to the formation of the partition wall by the conventional sandblasting method. FIG. 4A shows a step of forming a partition wall,
FIG. 4B shows a cross-sectional shape of a rib paste serving as a partition before the sandblast mask is stripped, and FIG. 4C shows a cross-sectional shape after the stripping. A conventional partition wall forming method will be described with reference to FIG. First, a rib paste (partition material) is applied to a predetermined thickness on a substrate and dried (S101). A DFR (dry film resist) is attached to the surface of the applied and dried rib paste (hereinafter simply referred to as rib paste) (S10).
2) Exposure is performed via a photomask having a partition pattern (S103). This is developed (and hardened) to form a sandblast mask having a partition pattern on the rib paste (S104).

Next, when sand blasting is performed from the side on which the sand blasting mask is formed, the rib paste is ground and dug down only on the surface where the mask does not exist, and a rib paste having a partition pattern is obtained as a remaining portion. (S105). When the sandblasting process is completed, the sandblasting mask is peeled off using a peeling solution (S106). Then, ribs are fixedly formed on the substrate by baking the rib paste in the partition pattern shape together with the substrate.

[0004]

In the conventional method of forming the partition on the plasma display substrate by the sandblasting method, the cross-sectional shape of the rib paste serving as the partition before performing the peeling treatment (S106) is shown in FIG. It is shown as follows. That is, the mask for sandblasting has a rectangular shape, and the side surface of the rib paste immediately below it is hollowed out, and the angle between the upper surface and the side surface of the rib paste is acute. This indicates that the strength of the sandblasting mask is high at the top corner, so that stress is concentrated, whereas the strength of the rib paste at that portion is low. If the peeling treatment is performed in this state, as shown in FIG. 4C, the cross-sectional shape of the rib paste is mainly chipped off at the corners of the apex to cause a defective shape, and the yield is significantly reduced. Also on the top surface, the strength of the rib paste is reduced by blasting. When the peeling treatment is performed in this state, a part of the rib paste is removed from the top surface, the top surface is roughened, the smoothness is lost, and the yield is significantly reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to prevent a rib paste serving as a partition from chipping off at a top corner to cause a shape defect.
In addition, without a loss of smoothness due to rough surface of the top,
It is an object of the present invention to provide a method of forming a partition of a plasma display panel, which significantly improves the yield. Another object of the present invention is to simplify a complicated process for forming a partition, which includes an exposure process, a development process, a peeling process, and the like.

[0006]

The above objects can be attained by the present invention described below. That is, the partition wall forming method according to claim 1 of the present invention comprises a partition wall material layer forming step of forming a partition wall material made of an easily grindable composition on a substrate in a predetermined thickness, A mask forming step of forming a mask for sandblasting of a desired pattern by printing a printing paste made of a hard-to-grind composition containing a glass frit having a lower softening point than that of the partition wall material as a component, A sandblasting process is performed from the mask forming surface side to grind the barrier rib material formed in the layer to form a barrier rib material having a desired pattern, and the sandblasting mask component excluding the glass frit is burned off and the desired components are burned out. And baking the partition material of the pattern to form the partition on the substrate. Than it is.

According to the present invention, a partition material made of an easily grindable composition is formed in a predetermined thickness on a substrate in a process of forming a partition material layer, and the partition material is formed in a predetermined thickness in a mask forming process. A sandblast mask of a desired pattern is formed by printing a printing paste made of a hard-to-grind composition containing a glass frit having a lower softening point than that of the partition wall material in the sandblasting process. By performing sand blasting from the forming surface side, the layered partition wall material is ground to form a desired pattern of partition wall material, and in the firing process, the components of the sand blast mask excluding the glass frit are burned off and the desired pattern is formed. Is fired, and the partition walls are fixedly formed on the substrate. That is, the used sandblasting mask has a burning property, so that a peeling process is not necessary, and a glass frit having a lower softening point than a partition material is included in the component, so that it is melted in the firing process and gives smoothness to the rough top surface. . Therefore, without the top surface being roughened and the smoothness being lost,
Yield is significantly improved. Furthermore, since a sandblast mask is formed by applying a printing method, an exposing step, a developing step, and the like are not required, and the step of forming the partition is greatly simplified.

According to a second aspect of the present invention, there is provided a method of forming a partition wall.
In the method of forming a partition according to claim 1, the mask for sandblasting is formed such that the cross-sectional shape of the mask is thinner on the side that is the side face of the partition and is thicker at the center of the partition. According to the present invention, the mask for sandblasting is formed as a thin film at the side where the film cross-sectional shape becomes the side surface of the partition and at the center of the partition. That is, the strength of the sandblasting mask is reduced at the corners of the apex by the mask having the film formed in the convex cross section. Therefore, the rib paste is ground and rounded at the top corners to increase the strength, and there is no stress concentration due to the mask. Therefore, the top corners of the rib paste serving as the partition walls are not chipped and a shape defect does not occur, and the effect of remarkably improving the yield is further remarkable.

According to a third aspect of the present invention, there is provided a method for forming a partition wall.
3. The method according to claim 1, wherein the printing paste is a printing paste containing a burnable thermoplastic resin as a component. According to the present invention, since a thermoplastic resin is used as a component, viscoelasticity suitable for printing is obtained as a printing paste, and flexibility suitable for blast resistance is obtained as a sandblasting mask.

[0010]

Next, the present invention will be described based on embodiments. FIG. 1 is an explanatory view of a process of forming a partition in the method of forming a partition according to the present invention. In FIG. 1, 1
Is a substrate (electrodes and dielectric layers are already formed), 2 is a rib paste, 3 is a printing paste, 4 is a rib material, 5 is a sandblast mask, and 6 is a rib. The partition wall forming method of the present invention provides a partition wall (barrier and rib) for forming a discharge space on a substrate (in many cases, a glass substrate) serving as a back plate (or a less common front plate) in a plasma display panel. Call). On the substrate, an electrode and a dielectric layer covering the electrode are formed in a previous step (not shown). The first step of forming the partition walls is a partition material layer forming step (S1) of forming a rib material 2 having a predetermined thickness on the substrate, that is, a rib material 2 made of an easily grindable composition.

The rib paste 2 is a material obtained by dispersing a glass frit made of PbO or the like, a heat-resistant pigment, or the like in an organic vehicle. In order to form a layer on a substrate by coating, a volatilization of an organic solvent or the like is performed. It is in the form of a paste containing a water-soluble (drying) composition and having application suitability. The coating of the rib paste on the substrate may be performed by a known method such as blade coating or knife coating, or disclosed in JP-A-63-171666.
Can be carried out by the flat plate coating method described in Japanese Patent Application Laid-Open No. H10-260, 1988.
After coating, heating and drying are performed under predetermined conditions. Assuming that the dried rib paste 2 is referred to as a partition wall material (rib material 5), in order to form a layer of the partition wall material with a predetermined thickness, the thickness of the rib paste 2 must be set in consideration of the amount of drying and weight reduction. The rib paste 2 is applied.

Then, this partition material layer forming step (S1)
Is followed by a mask forming step (S2). The mask formation process
A sandblast mask 5 having a desired pattern is formed by printing a printing paste 3 made of a hard-to-grind and burn-off composition containing a glass frit having a softening point lower than that of the partition wall material on the formed partition wall material. Is the process of forming Although the present invention is not limited by the printing method, a screen printing method, a gravure printing method, or the like can be applied.

The printing paste 3 will be described in detail later. For example, a printing paste having the following composition can be used. (An example of the composition of the printing paste) glass frit ..... 70 parts by weight of the main _{component; Bi 2 O 3, ZnO,} B 2 O 3 ( alkali-free), the average particle diameter of 3 [mu] m TiO ₂ · · · · · · 3 Parts by weight Ai ₂ O ₃ ... 7 parts by weight The softening point of the mixture of these inorganic components is 570 ° C.
Tg is 485 ° C., coefficient of thermal expansion α300 is 80 × 10 ⁻⁷ /
° C n-butyl methacrylate / hydroxyethylhexyl methacrylate copolymer (8/2) 10 parts by weight Benzyl butyl phthalate 7 parts by weight Propylene glycol monomethyl ether 20 parts by weight Was mixed and dispersed using a bead mill to obtain a printing paste.

Next is a drying and curing step (S3). The printed paste 2 having a desired pattern is subjected to a curing treatment by heating, irradiation with ionizing radiation, or the like, as necessary. The printing paste 3 printed by this curing process and having a desired pattern can obtain physical properties as a sandblast mask 5.

In the subsequent sandblasting step (S4), the material of the partition walls (rib material 5) is formed by performing sandblasting from the side of the mask 5 for sandblasting.
Is a process of forming a partition wall material having a desired pattern by grinding. For example, brown fused alumina # 800 as an abrasive
By performing sandblasting at an ejection pressure of 1 kg / cm ² to obtain a predetermined shape, for example, a line width of 100 kg / cm ^2.
A rib 6 having a thickness of 200 μm, a pitch of 200 μm, and a height of 200 μm is obtained.

In the firing step (S5), the components of the sand blast mask excluding the glass frit are burned off, and a partition material having a desired pattern is baked to fix the partition on the substrate. For example, baking is performed under the conditions of a peak temperature of 585 ° C. and a holding time of 10 to 20 minutes.
The components excluding the glass frit of the sand blast mask 5 forming a film by this baking are burned off, and the ribs 6 are fixedly formed on the glass substrate 1. At this time, the glass frit contained in the mask for sandblasting is melted to smooth the top surface of the rib 6.

It is apparent that the above-described process of the present invention is greatly simplified in comparison with the above-described process of the partition forming method using the DFR. That is, the DFR bonding (S102), the exposure (S103) through a photomask having a partition pattern, and the development (S104) are performed only in the mask forming process (S2), and the exposure (S103) and the development (S103) are substantially performed. The step of S104) becomes unnecessary.
Further, the removal of the sandblast mask is removed (S106).
Becomes unnecessary. Thus, in the present invention, the process of forming the partition is significantly simplified.

The cross-sectional shape of the rib 6 (partition) after the above-described sandblasting step (S4) and firing step (S5) will be described. FIG. 2A shows the cross-sectional shape of the partition wall after the sandblasting process, and FIG.
It is shown in (B). As shown in FIG. 2 (A), the sandblasting mask 5 after the sandblasting step (S4) has a thinner film cross-sectional shape on the side of the partition wall and a thicker film at the center of the partition wall. This is because a mask has already been formed with such a cross-sectional shape in the mask forming step (S2) (see FIG. 1S2). As described above, since the film for the sandblasting mask 5 is formed to have a convex cross-sectional shape, the strength is reduced at the top corner. Therefore, the rib paste is ground and rounded at the top corners to increase the strength, and the concentration of stress by the sandblast mask 5 is also eliminated. That is, the top corners of the rib paste serving as the partition walls are not chipped off, and the shape accuracy and the yield are improved.

After the firing step (S5), FIG.
As shown in (B), the components of the composition of the sandblasting mask 5 that do not burn out, that is, the glass frit is melted to form the molten glass layer 6. In addition, the overall dimension shrinks during the process of singulation of the rib material by firing. FIG. 3 is an explanatory diagram relating to the action of melting the glass frit in the firing step (S5). As shown in FIG. 3A, the surface of the sandblasting mask 5 after the sandblasting step (S4) has irregularities and is rough. As shown in FIG. 3 (B), the top surface of the rib 6 (partition) after the firing step (S5) has a rough top formed by melting glass frit having a softening point lower than that of the partition material (rib material 4). Smooth the surface.

Next, the printing paste will be described. In the partition wall forming method of the present invention, a printing paste made of a hard-to-grind and burn-off composition containing glass frit having a softening point lower than that of the partition wall material is used. As already described, the reason that the glass frit having a softening point lower than that of the partition wall material was included in the component was that the glass frit was melted during the firing process and flowed to the rough top surface, so that the top surface was made smooth. To give. As a result, the top surface is roughened and the smoothness is not lost.
The effect of significantly improving the yield can be obtained.

Here, the difficulty in grinding is the difficulty of grinding of the sandblast mask 4 formed by using the printing paste. That is, the hard-to-grind composition is a composition from which a sand-blasting mask 4 that is difficult to grind and can withstand sufficiently in the sand blasting process (S4) is obtained. Here, the burnout property is the burnout property of the sandblast mask 4 formed using the printing paste. That is, the burnable composition is a composition in which the residue (residual substance) in the rib 5 and the substrate is reduced to a level that does not cause a problem in the firing step (S5).

The glass frit in the composition of the printing paste has a softening point of 350 ° C. to 650 ° C. and a coefficient of thermal expansion α300 of 60 × 10 ⁻⁷ / ° C. to 100 × 10 ⁻⁷ /.
° C can be used. If the softening point of the glass frit exceeds 650 ° C., it is necessary to raise the firing temperature. If the temperature is lower than 350 ° C., the thermoplastic resin or the like is decomposed,
Before volatilization, the glass frit is fused, and voids and the like are formed in the layer, which is not preferable. Further, the thermal expansion coefficient is 60 × 10 ⁻⁷ /
When the temperature is out of the range of 100 to 10 × 10 ⁻⁷ / ° C., the difference from the thermal expansion coefficient of the glass substrate is large, and distortion or the like is undesirably caused.

As the inorganic powder in the composition of the printing paste, aluminum oxide, boron oxide, silica, titanium oxide, magnesium oxide, calcium oxide, strontium oxide, barium oxide, calcium carbonate, etc. may be used. it can.

As the inorganic pigment in the composition of the printing paste, Co-Cr-F
e, Co-Mn-Fe, Co-Fe-Mn-Al, Co
-Ni-Cr-Fe, Co-Ni-Mn-Cr-Fe,
Co-Ni-Al-Cr-Fe, Co-Mn-Al-C
r-Fe-Si or the like can be used. In addition, as the fire-resistant white pigment, titanium oxide, aluminum oxide, silica, calcium carbonate, and the like can be used.

As the thermoplastic resin in the composition of the printing paste, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n
-Propyl acrylate, n-propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, te
rt-butyl methacrylate, n-pentyl acrylate, n-pentyl methacrylate, n-hexyl acrylate, n-hexyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, n-octyl acrylate, n-octyl methacrylate, n-decyl acrylate, n-decyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, styrene, α
1 such as methylstyrene, N-vinyl-2-pyrrolidone, etc.
Polymers or copolymers of more than one species, cellulose derivatives such as ethylcellulose and the like can be used.

Of these, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate are particularly preferred. , Isobutyl acrylate, isobutyl methacrylate, ter
t-butyl acrylate, tert-butyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate,
Ethyl cellulose, a polymer or copolymer composed of one or more of hydroxypropyl methacrylate and the like.

Examples of the plasticizer in the composition of the printing paste include normal alkyl phthalates such as dimethyl phthalate, dibutyl phthalate and di-n-octyl phthalate, di-2-ethylhexyl phthalate, diisodecyl phthalate, butyl benzyl phthalate, and the like. Phthalates such as diisononyl phthalate, ethyl phthalethyl glycolate and butyl phthalyl butyl glycolate; tri-2-ethylhexyl trimellitate;
trimellitate such as n-alkyl trimellitate, triisononyl trimellitate, triisodecyl trimellitate, dimethyl adipate, dibutyl adipate, di-2-ethylhexyl adipate, diisodecyl adipate, dibutyl diglycol adipate, di- 2
-Ethylhexyl acetate, dimethyl sebacate, dibutyl sebacate, di-2-ethylhexyl sebacate, di-2-ethylhexyl malate, acetyl-tri- (2-ethylhexyl) citrate, acetyl-tri-n-butyl citrate, acetyl -Aliphatic dibasic acid esters such as tributyl citrate, polyethylene glycol benzoate, triethylene glycol di-
(2-ethylhexoate), glycol derivatives such as polyglycol ether, glycerol triacetate,
Glycerin derivatives such as glycerol diacetyl monolaurate, polyesters composed of sebacic acid, adipic acid, azelaic acid, phthalic acid, etc., molecular weight 300 to 300
0 low molecular weight polyether, the same low molecular weight poly-α-styrene, the same low molecular weight polystyrene, trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate, tributoxyethyl phosphate, triphenyl phosphate,
Orthophosphates such as tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, xyenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, ricinoleates such as methyl acetyl ricinoleate, poly-1,
Polyester / epoxidized esters such as 3-butanediol adipate and epoxidized soybean oil, and acetates such as glycerin triacetate and 2-ethylhexyl acetate can be used.

Antifoaming agents in the printing paste composition include silicone-based, acrylic-based, various surfactants,
Etc. can be used. As the leveling agent in the composition of the printing paste, a fluorine type, a silicone type, various surfactants, and the like can be used. As the dispersant and the anti-settling agent in the composition of the printing paste, phosphate ester type, silicone type, castor oil ester type, various surfactants and the like can be used.

Solvents in the composition of the printing paste include anones such as methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, toluene, xylene, cyclohexane, methylene chloride, 3-methoxybutyl acetate, and ethylene glycol alkyl ether acetate. , Diethylene glycol monoalkyl ethers, diethylene glycol monoalkyl ether acetates, propylene glycol monoalkyl ether acetates, dipropylene glycol monoalkyl ethers, dipropylene glycol monoalkyl ether acetates, and tempers such as α- or β-terpionaire , Etc. can be used.

[0030]

As described above, according to the method of forming a partition according to the first aspect of the present invention, the top corner of the rib paste serving as the partition is not chipped and a shape defect does not occur, and the top surface is roughened. The yield is significantly improved without loss of smoothness. Furthermore, since a sandblast mask is formed by applying a printing method, an exposing step, a developing step, and the like are not required, and the step of forming the partition is greatly simplified.
According to the method of forming a partition according to claim 2 of the present invention, the mask formed with the film having a convex cross-sectional shape does not cause the top corners of the rib paste serving as the partition to be chipped, resulting in poor shape, and significantly increases the yield. The effect of improving becomes more remarkable. According to the method of forming a partition according to claim 3 of the present invention, since a thermoplastic resin is used as a component, viscoelasticity suitable for printing is obtained as a printing paste, and flexibility suitable for blast resistance as a sandblast mask. Is obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a partition forming process in a partition forming method of the present invention.

FIG. 2 is a view showing a sectional shape of a partition wall after a sandblasting process and a firing process.

FIG. 3 is a diagram illustrating the action of melting glass frit in a firing process.

FIG. 4 is a pictorial diagram related to formation of a partition wall by a conventional sandblast method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Rib paste (partition material) 3 Printing paste 4 Rib material 5 Sandblast mask 6 Rib (partition) 7 Molten glass layer

Claims (3)

[Claims] 1. A partition material layer forming step of forming a partition material made of an easily grindable composition in a predetermined thickness on a substrate, and a softening point lower than that of the partition material on the layer-formed partition material. A mask forming process of forming a sand blast mask of a desired pattern by printing a printing paste made of a hard-to-grind composition containing a glass frit as a component, and performing a sand blasting process from the formation surface side of the sand blast mask. A sand blasting step of grinding the layer-formed partition material to form a desired pattern of partition material by burning the components of the sand blast mask excluding the glass frit and firing the desired pattern of the partition material; A baking process in which partition walls are fixedly formed on the substrate; and Partition wall forming method. 2. A plasma display panel according to claim 1, wherein said sandblasting mask is formed as a thin film at a side having a cross-sectional shape corresponding to a side surface of said partition and a thick film at a center of said partition. Partition wall forming method. 3. The method according to claim 1, wherein the printing paste is a printing paste containing a burnable thermoplastic resin as a component.