JP2008138152A - Glass paste and manufacturing method of plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a glass paste capable of efficiently producing a plasma display panel and a manufacturing method of the plasma display panel using the glass paste. <P>SOLUTION: The glass paste contains at least a (meth)acrylic resin comprising a monomer whose homopolymer has a glass transition temperature (Tg) of ≥20°C, glass powders and a solvent having a specific gravity of ≥0.95 and <1.35 and a boiling point of ≥140°C and <300°C. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a glass paste capable of efficiently producing a plasma display panel and a method for producing a plasma display panel using the glass paste.

A plasma display panel (hereinafter also referred to as PDP) is an ultraviolet ray generated from a gas enclosed in a discharge space by causing plasma discharge between electrodes in a discharge space provided between the front glass substrate and the rear glass substrate. Is emitted to the phosphor in the discharge space.
On the rear glass substrate, a dielectric layer is formed on the electrode for the purpose of protecting the electrode from plasma, and a glass rib for coating the phosphor layer is formed on the surface. Further, in order to increase the surface area of the phosphor layer, the glass rib is formed into a concave stripe shape using sandblast. A substrate in which a dielectric layer and glass ribs are formed on the back glass substrate surface is called a back plate.

Conventionally, in a PDP production process, as disclosed in Patent Document 1, a dielectric layer paste is applied to the surface of a rear glass substrate, dried, heated, and then degreased and fired to obtain a dielectric. A layer is formed, and on the surface of the dielectric layer, acrylic resin or ethyl cellulose resin is used as a binder resin, low melting point glass is dispersed, a solvent-containing glass rib paste is applied, and then sand blasting is used to form a concave shape. After forming into a stripe shape, the glass rib was formed by heating and degreasing and baking. In this process, the process of heating, degreasing and baking is required a plurality of times, and there is a problem that it takes heat energy and manufacturing tact time.

With respect to such a problem, the dielectric layer and the glass rib are manufactured by degreasing and firing only once by forming the dielectric precursor layer and the glass rib precursor on the surface of the back glass substrate and heating them together. It is being considered. However, when a conventional glass rib paste is applied to the surface of a dielectric precursor layer that has not been degreased and baked, there is a problem that a phenomenon called sheet attack occurs in which the solvent contained in the paste destroys the dielectric layer. It was.
In Patent Document 2, a dielectric paste is applied to the back glass substrate surface, a glass rib paste is applied to a dielectric precursor layer cured by thermal polymerization, and a dielectric precursor layer and a glass rib precursor are applied. Although a method of firing and producing a dielectric layer and a glass rib is disclosed, it is difficult to completely terminate thermal polymerization in a short time, and it is difficult to evaporate the solvent after curing. There was a problem that peeling from the substrate and bubbles were generated.
JP 2002-133947 A JP 2001-26477 A

An object of this invention is to provide the glass paste which can manufacture a plasma display panel efficiently, and the manufacturing method of a plasma display panel using this glass paste in view of the said present condition.

In the present invention, at least a (meth) acrylic resin composed of a monomer having a glass transition temperature (Tg) of a homopolymer of 20 ° C. or higher, a glass powder, a specific gravity of 0.95 to less than 1.35, and a boiling point It is a glass paste containing a solvent at 140 ° C. or higher and lower than 300 ° C.
The present invention is described in detail below.

As a result of intensive studies, the inventors of the present invention have used a resin having a glass transition temperature equal to or higher than a certain temperature as a binder resin in a glass paste, and using a solvent having a specific gravity and a boiling point within a certain range. When a display panel is manufactured, after the dielectric precursor layer is dried and after the concave shape is formed by sandblasting, sheet attack does not occur without performing degreasing and firing, respectively, thus reducing degreasing and firing. As a result, it has been found that a plasma display panel can be produced efficiently, and the present invention has been completed.

The glass paste of this invention contains the (meth) acrylic resin which consists of a monomer whose glass transition temperature (Tg) of a homopolymer is 20 degreeC or more. Here, the glass transition temperature of the homopolymer in the present invention is the glass transition temperature of a homopolymer having a weight average molecular weight of 5000 or more.
If the glass transition temperature is less than 20 ° C, problems may occur during sandblasting. In addition, since a large amount of resin is required to obtain a viscosity sufficient for coating, it takes time for degreasing and firing.

The (meth) acrylic resin is not particularly limited. For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, tert-butyl (meth) acrylate, isobutyl (Meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isobornyl (meth) acrylate, n-stearyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and A polymer comprising at least one selected from the group consisting of (meth) acrylate monomers having a polyoxyalkylene structure is suitably used. Here, for example, (meth) acrylate means acrylate or methacrylate.
Among them, since a high viscosity can be obtained with a small amount of resin, the glass transition temperature (Tg) is high, and since it can be quickly degreased at a low temperature, polymethyl methacrylate (Tg 108 ° C.), which is a copolymer of methyl methacrylate. ) Is preferred.

Although it does not specifically limit as a weight average molecular weight by polystyrene conversion of the said (meth) acrylic resin, A preferable minimum is 5000 and a preferable upper limit is 200,000. If it is less than 5000, sufficient viscosity cannot be obtained in the glass paste of the present invention. If it exceeds 200,000, the resin cohesive force is high, and it becomes difficult to form by sandblasting, and yarn spinning occurs during coating. May adversely affect the coating operation of the glass paste. A more preferred upper limit is 30,000, and a more preferred upper limit is 20,000.
Moreover, when the weight average molecular weight is 10,000 to 20,000, the sandblasting work is good, the surface of the glass paste after coating and drying is smooth, and the stringiness is excellent, which is particularly preferable.
In addition, the measurement of the weight average molecular weight by polystyrene conversion can be obtained by performing GPC measurement using, for example, a column LF-804 manufactured by SHOKO as a column.
In addition, when the reaction solution after the (meth) acrylic resin polymerization reaction is used as it is as the binder resin used in the glass paste of the present invention, low molecular weight components such as monomers and oligomers are substantially contained in the polymerization solution after polymerization. It is preferable that it is not contained in.

The molecular weight distribution (weight average molecular weight / number average molecular weight = Mw / Mn) of the (meth) acrylic resin is not particularly limited, but the preferred upper limit is 3. When the molecular weight distribution exceeds 3, a low molecular weight component such as an oligomer in the polymerization solution becomes a plasticizer, and sufficient viscosity cannot be obtained in the glass paste, or the high molecular weight component may deteriorate the stringiness. A more preferred upper limit is 2.5.

Although it does not specifically limit as content of the said (meth) acrylic resin in the glass paste of this invention, A preferable minimum is 5 weight% and a preferable upper limit is 25 weight%. If it is less than 5% by weight, the glass powder may not be sufficiently dispersed, and the surface of the glass paste after coating and drying may not be smooth. If it exceeds 25% by weight, it will have an adverse effect during sandblasting. May affect.

The glass paste of the present invention contains glass powder.
It is not particularly restricted but the composition of the glass powder, for example, silicate glass, lead _{glass, CaO · Al 2 O 3 ·} SiO 2 type inorganic _{glass, MgO · Al 2 O 3 ·} SiO 2 type inorganic glass, LiO ₂ · _{Al 2 O} 3 · SiO 2 system various glasses such as inorganic glass. In particular, a low melting point glass having a melting point of 600 ° C. or lower is preferable.

Moreover, you may use together inorganic fine particles other than glass with respect to the said glass powder. The inorganic fine particles are not particularly limited, and for example, copper, silver, nickel, palladium, alumina, zirconia, titanium oxide, barium titanate, alumina nitride, silicon nitride, boron nitride, BaMgAl ₁₀ O ₁₇ : Eu, Zn ₂ SiO ₄ : Phosphors such as Mn, (Y, Gd) BO ₃ : Eu, carbon black, metal complexes, and the like.

Although it does not specifically limit as content of the said glass powder and inorganic fine particle in the glass paste of this invention, A preferable minimum is 10 weight% and a preferable upper limit is 80 weight%. If it is less than 10% by weight, the viscosity may not be sufficiently obtained, and since the resin is more than the glass powder or the like, there may be an adverse effect during sandblasting. If it exceeds 80% by weight, it may be difficult to disperse the glass powder and the like.

The glass paste of the present invention contains a solvent having a specific gravity of 0.95 or more and less than 1.35 and a boiling point of 140 ° C. or more and less than 300 ° C.

The solvent has a specific gravity of 0.95 or more and less than 1.35. If the specific gravity is out of this range, a sheet attack may occur or coating may become difficult. Here, the specific gravity means the ratio of the density of water at 4 ° C. or 20 ° C. to the density of the solvent at 20 ° C. or 25 ° C. (Editor: Shozo Asahara, “Solvent Handbook”, Kodansha, January 1996) 14th printing on the 20th).
Among the solvents listed below as examples, conventionally known ones may also be mentioned, but in consideration of the degreasing and baking process, solvents having a specific gravity of 0.95 or more and less than 1.35 are used because they are difficult to evaporate. The current situation was not. However, the present inventors have found for the first time that sheet attack can be prevented by using such a solvent having a specific gravity and a boiling point.

The solvent has a boiling point of 140 ° C. or higher and lower than 300 ° C. If the boiling point is less than 140 ° C., the solvent will be volatilized when the glass paste of the present invention is applied, so that the viscosity changes and stable coating cannot be performed. A great deal of time and heat energy are required at the stage of drying the solvent in the paste. Preferably it is 280 degrees C or less.

The solvent having a specific gravity of 0.95 or more and less than 1.35 and a boiling point of 140 ° C. or more and less than 300 ° C. is not particularly limited. For example, ethylene glycol diacetate (specific gravity 1.1063 (solvent 20 ° C./water 20 ° C. ), Boiling point 190.2 ° C.), propylene carbonate (specific gravity 1.2069 (solvent 20 ° C./water 20 ° C.), boiling point 242 ° C.), diethylene glycol (specific gravity 1.1164 (solvent 20 ° C./water 4 ° C.)), boiling point 244. 8 ° C), 1,2-ethanediol (specific gravity 1.1135 (solvent 20 ° C / water 4 ° C), boiling point 197.85 ° C), 1,2-propanediol (specific gravity 1.0381 (solvent 20 ° C / water 20) ), Boiling point 187.3 ° C., 1,3-propanediol (specific gravity 1.0554 (solvent 20 ° C./water 20 ° C.), boiling point 214 ° C.), 1,2-butanediol (specific gravity 1.0024 (solvent 2) ° C / water 4 ° C), boiling point 190.5 ° C), 1,3-butanediol (specific gravity 1.0053 (solvent 20 ° C / water 4 ° C), boiling point 207.5 ° C), 1,4-butanediol (specific gravity) 1.069 (solvent 20 ° C / water 4 ° C), boiling point 229.2 ° C), 1,5-pentanediol (specific gravity 0.9938 (solvent 20 ° C / water 4 ° C), boiling point 242.4 ° C), 2- Diols such as butene-1,4-diol (specific gravity 1.080 (solvent 20 ° C./water 4 ° C.), boiling point 235 ° C.), diethylene glycol monoethyl ether acetate (specific gravity 1.0096 (solvent 20 ° C./water 20 ° C.)) , Boiling point 217.4 ° C.), diethylene glycol monobutyl ether acetate (specific gravity 0.9810 (solvent 20 ° C./water 20 ° C.), boiling point 246.8 ° C.), 2-phenoxyethyl acetate (specific gravity 1.1084 (solvent 2) ° C / water 20 ° C), boiling point 259.7 ° C), 2-ethoxyethyl acetate (specific gravity 0.9730 (solvent 20 ° C / water 4 ° C), boiling point 156.3 ° C), 2-methoxyethyl acetate (specific gravity 1. 0049 (solvent 20 ° C./water 4 ° C.), boiling point 144.5 ° C.), γ-butyrolactone (specific gravity 1.1254 (solvent 25 ° C./water 4 ° C.), boiling point 204 ° C.), dimethyl sulfoxide (specific gravity 1.0958 (solvent) 25 ° C / water 4 ° C), boiling point 189 ° C, N-methylpyrrolidone (specific gravity 1.0279 (solvent 25 ° C / water 4 ° C), boiling point 202 ° C), N-methylformamide (specific gravity 0.9988 (solvent 25 ° C) / Water 4 ° C.), boiling point 180 ° C.), formamide (specific gravity 1.13339 (solvent 20 ° C./water 4 ° C.), boiling point 210.5 ° C.) and the like.
Among them, the dielectric constant is preferably 25 or more because sheet attack is particularly difficult to occur. As the solvent having a dielectric constant of 25 or more, 1,2-ethanediol, 1,2-propanediol, 1,3- Examples include propanediol, 1,4-butanediol, diethylene glycol, propylene carbonate, γ-butyrolactone, dimethyl sulfoxide, N-methylpyrrolidone, N-methylformamide, and formamide. In particular, propylene carbonate, γ-butyrolactone, 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, and 1,4-butanediol are suitable because they can be dried at 200 ° C. or lower. Yes (see “Solvent Handbook”).
In addition, these solvents may be used independently and 2 or more types may be used together.

In addition, the glass paste of the present invention preferably further contains a polyvinyl acetal resin in order to improve adhesion with a dielectric film or a dry film resist (DFR) necessary for patterning in sandblasting.
When the glass paste of the present invention contains a polyvinyl acetal resin, the polyvinyl acetal resin can be sufficiently dissolved in the glass paste, so that the solvent includes 1,2-ethanediol, 1,2-propanediol. 1,3-propanediol and 1,4-butanediol are preferably used.

Although it does not specifically limit as a hydroxyl value of the said polyvinyl acetal resin, In order to ensure the solubility to the said solvent, it is preferable that it is 40 mol% or more. If it is less than 40 mol%, the solvent may not be sufficiently dissolved.

Although it does not specifically limit as a weight average molecular weight by polystyrene conversion of the said polyvinyl acetal resin, A preferable minimum is 5000 and a preferable upper limit is 100,000. If it is less than 5000, effects such as improvement in adhesion and toughness due to the use of the polyvinyl acetal resin may not be sufficiently obtained, and if it exceeds 100,000, the solubility in the solvent may be lowered. A more preferable lower limit is 10,000, and a more preferable upper limit is 50,000.

Although it does not specifically limit as content of the said polyvinyl acetal resin in the glass paste of this invention, A preferable minimum is 0.1 weight% and a preferable upper limit is 6 weight%. When the content is less than 0.1% by weight, the effects of improving the adhesion and toughness due to the use of the polyvinyl acetal resin may not be sufficiently obtained. When the content exceeds 6% by weight, degreasing is performed at a high temperature. There is a possibility that firing in is necessary.

The glass paste of the present invention preferably contains a nonionic surfactant for the purpose of promoting leveling after coating.

The nonionic surfactant is not particularly limited, but is preferably a nonionic surfactant having an HLB value of 6 or more and 16 or less. Here, the HLB value is used as an index representing the hydrophilicity and lipophilicity of a surfactant, and several calculation methods have been proposed. For example, saponification value of an ester-based surfactant And S, the acid value of the fatty acid constituting the surfactant is A, and the HLB value is 20 (1-S / A). Specifically, those obtained by adding an alkylene ether to a fatty chain are preferable, and specifically, for example, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, and the like are preferably used. In addition, although the said nonionic surfactant has good thermal decomposability, since the thermal decomposability of a glass paste may fall when it adds abundantly, the upper limit with preferable content is 5 weight%.

It does not specifically limit as a preparation method of the glass paste of this invention, A conventionally well-known stirring method is mentioned, For example, (meth) acrylic resin, glass powder, a solvent, and added as needed Examples include a method of stirring other components with a three-roll mill or the like.

As an application of the glass paste of the present invention, when a ceramic paste composition using a ceramic powder, a phosphor paste composition using a phosphor powder, or a conductive powder is used instead of the glass powder to be dispersed The conductive paste composition, glass powder, or ceramic powder can be used as a green sheet. By using it for such an application, it can be degreased and fired simultaneously with a green sheet using ethyl cellulose as a binder resin.
In other words, taking advantage of the fact that no sheet attack occurs, the process of drawing a pattern with a conductive paste on a green sheet, which had previously required an individual sintering process, the process of covering the dielectric paste on the electrode sheet, and the rib sheet In addition, it is possible to simplify the process of screen printing the phosphor paste.
Further, the present invention can also be applied when combining different printing methods such as printing a phosphor paste by inkjet on an unsintered rib or screen printing a dielectric layer after printing an electrode by offset printing. For example, the process of drawing a sandblast resist pattern by a photolithography process is replaced with screen printing.

By using the glass paste of the present invention, when a plasma display panel is produced, a sheet attack is generated even if a dielectric precursor layer and a glass rib precursor are formed on the back glass substrate surface and then degreased and fired together. Therefore, there is no problem that it takes heat energy and manufacturing tact time as in the prior art.
A dielectric precursor layer forming step for forming a dielectric precursor layer by applying a dielectric layer paste containing cellulose resin as a main component on a back glass substrate and then drying, and the dielectric without performing a degreasing step A glass rib precursor forming step of forming the glass rib precursor by applying the glass paste of the present invention to the surface of the precursor layer and drying, a concave shape forming step of forming a concave shape on the glass rib precursor by sandblasting, A method of manufacturing a plasma display panel having a degreasing / firing step of heating and degreasing / firing the dielectric precursor layer and the glass rib precursor is also one aspect of the present invention.
In addition, a dielectric precursor layer forming step for forming a dielectric precursor layer by applying the glass paste of the present invention to a back glass substrate and drying, and cellulose on the surface of the dielectric precursor layer without performing a degreasing step A glass rib precursor forming step of forming a glass rib precursor by applying a resin-based paste for glass rib and drying, and a concave shape forming step of forming a concave shape on the glass rib precursor by sandblasting; A method of manufacturing a plasma display panel having a degreasing / firing step of heating and degreasing / firing the dielectric precursor layer and the glass rib precursor is also one aspect of the present invention.
Here, examples of the cellulose resin include methyl cellulose, ethyl cellulose, hydroxy cellulose, and nitro cellulose.

As described above, the plasma display panel manufacturing method of the present invention uses the glass paste of the present invention containing a specific solvent, as described above, and after the dielectric precursor layer is dried when the plasma display panel is manufactured conventionally. Since the sheet attack does not occur without performing the degreasing and firing steps after forming the concave shape with sandblasting, the degreasing and firing steps can be reduced, so that the plasma display panel can be manufactured efficiently. Can do.
In addition, about each process, operation similar to the manufacturing method of the conventional plasma display panel can be performed except using the glass paste of this invention and reducing a degreasing process. The dielectric layer paste and glass rib paste are not particularly limited as long as they do not easily react with the solvent contained in the glass paste of the present invention, and conventionally known ones can be used.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the glass paste which can manufacture a plasma display panel efficiently, and this plasma paste using this glass paste can be provided.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

(Example 1)
In a 2 L separable flask equipped with a stirrer, cooler, thermometer, hot water bath, and nitrogen gas inlet, 100 parts by weight of methyl methacrylate (MMA), dodecyl mercaptan as a chain transfer agent, and 100 parts by weight of propylene carbonate as a solvent Mixing was performed to obtain a monomer mixture.

The obtained monomer mixture was bubbled with nitrogen gas for 20 minutes to remove dissolved oxygen, and then the temperature inside the separable flask system was replaced with nitrogen gas and heated until the hot water bath boiled with stirring. A solution obtained by diluting the polymerization initiator with ethyl acetate was added. During the polymerization, an ethyl acetate solution containing a polymerization initiator was added several times.

Seven hours after the start of polymerization, the polymerization was terminated by cooling to room temperature. Thereby, a propylene carbonate solution of a methacrylic resin was obtained. The obtained polymer was analyzed by gel permeation chromatography using a column LF-804 manufactured by SHOKO as a column, and the weight average molecular weight in terms of polystyrene was as shown in Table 1.
Propylene carbonate is further added to the propylene carbonate solution of the (meth) acrylic resin thus obtained so as to achieve the composition ratio shown in Table 1, and dispersed with a high-speed disperser to produce a binder resin composition. did.

Table 1 shows BL-2 (manufactured by Nikko Chemical Co., Ltd.) as a nonionic surfactant and low melting glass fine particles ABX-169F (manufactured by Tokan Material Technology Co., Ltd.) as a glass frit with respect to the obtained binder resin composition. It added so that it might become a composition ratio, fully knead | mixed using the high-speed stirring apparatus, it processed until it reached the smooth state with the 3 roll mill, and produced the glass paste.

(Examples 2-3)
Except having adjusted the addition amount of the chain transfer agent, it superposed | polymerized like Example 1 and obtained the propylene carbonate solution of the methacryl resin. The weight average molecular weight was as shown in Table 1. Each component was adjusted so that it might become the composition ratio of Table 1, and it carried out similarly to Example 1, and produced the binder resin composition and the glass paste.

Example 4
A binder resin composition and a glass paste were prepared in the same manner as in Example 1 except that the monomer used was changed to isobutyl methacrylate (IBMA).

(Example 5)
A binder resin composition and a glass paste were prepared in the same manner as in Example 1 except that the monomer used was changed to cyclohexyl methacrylate (CHMA).

(Example 6)
A binder resin composition and a glass paste were prepared in the same manner as in Example 1 except that two monomers of 80 parts by weight of methyl methacrylate and 20 parts by weight of lauryl methacrylate (LMA) were used.

(Example 7)
The binder resin composition was the same as in Example 1 except that 80 parts by weight of methyl methacrylate and 20 parts by weight of an acrylic monomer having a propylene oxide unit (Blenmer PP1000) were used. The thing and the glass paste were produced.

(Comparative Examples 1-2)
A 10% by weight terpineol (specific gravity 0.93 (solvent 20 ° C./water 4 ° C.)) solution of ethyl cellulose (Sigma Aldrich STD46 or STD100) was prepared, and each component was adjusted to the composition ratio shown in Table 2. In the same manner as in Example 1, a binder resin composition and a glass paste were produced.

(Comparative Example 3)
Polymerization was carried out in the same manner as in Example 1 except that terpineol was used as a solvent by adjusting the amount of chain transfer agent added to obtain a methacrylic resin (polymethyl methacrylate PMMA). The weight average molecular weight was as shown in Table 2. Each component was adjusted so that it might become the composition ratio of Table 2, and it carried out similarly to Example 1, and produced the binder resin composition and the glass paste.

(Comparative Example 4)
A 10% by weight propylene carbonate solution of ethyl cellulose (Sigma Aldrich STD100) was prepared, each component was adjusted to the composition ratio shown in Table 2, and the binder resin composition and glass were prepared in the same manner as in Example 1. A paste was prepared.
However, since the ethylcellulose resin was not dissolved in the solvent, a paste could not be prepared.

<Evaluation>
The following evaluation was performed about the binder resin composition and glass paste obtained in Examples 1-7 and Comparative Examples 1-3. The results are shown in Tables 1 to 3.

(1) Sheet attack resistance The glass paste produced by the same method as Comparative Example 1 was coated on a glass substrate (2 cm × 5 cm) using an applicator set to 10 mil. The terpineol contained in the paste was evaporated in an oven at 120 ° C. for 30 minutes to form an ethylcellulose-containing dielectric precursor layer. Thickness was 10 microns and it was dense, and the coated surface of the glass paste was smooth.
It applied to the dielectric precursor layer using the applicator which set the binder resin composition to 5 mil which does not contain surfactant and glass powder of Examples 1-7 and Comparative Examples 1-3. Curing was performed in a 120 ° C. oven for 30 minutes to evaporate the solvent component, and the state of the dielectric precursor layer was confirmed by microscopic observation. The case where a hole was found in the dielectric precursor layer was marked as x, and the case where there was no change was marked as ◯.

(2) Rib surface property and sandblasting property A glass paste produced by the same method as in Comparative Example 1 was coated on a glass substrate (2 cm × 5 cm) using an applicator set to 7 mil. The terpineol contained in the paste was evaporated in an oven at 120 ° C. for 30 minutes to form an ethylcellulose-containing dielectric precursor layer. Thickness was 50 microns and it was dense, and the coated surface of the glass paste was smooth. After coating the glass pastes of Examples 1 to 7 and Comparative Examples 1 to 3 on the dielectric precursor layer, it was formed to a thickness of 400 microns with a knife coater, dried in an oven at 120 ° C. for 1 hour, and a glass rib precursor with a thickness of 180 microns. The body was molded.
A dry film resist for sandblasting (manufactured by Tokyo Ohka Kogyo Co., Ltd., BF603) was laminated at 50 ° C. on the glass rib precursor, an exposure mask was set, and exposure was performed at 300 mJ / cm ² . Development was performed with a 0.2% aqueous sodium carbonate solution to form a line and space pattern having a width of 100 microns.
The case where the adhesion of the dry resist film onto the glass rib precursor was good was designated as rib surface property ◯, and the case where fine bubbles did not escape was designated as rib surface property x.
Using a sandblasting machine (Pneuma Blaster SMC-1ADE-NE-401) manufactured by Fuji Seisakusho on the surface on which the pattern was formed, an abrasive (S4 # 1000 manufactured by Fuji Seisakusho) was sprayed at an ejection pressure of 0.15 MPa to perform sandblasting. went.
When the cutting progresses promptly and there is no problem with the rib shape, ◎, when the cutting progresses to the dielectric precursor layer, ◯ when the dry film resist is peeled off before the cutting is finished, and cutting to the bottom When X did not advance, it was set as x.

(Example 8)
(Synthesis of polyvinyl acetal resin)
180 g of polyvinyl alcohol having a polymerization degree of 360 and a saponification degree of 98 mol% was added to 3000 mL of pure water, and stirred at 90 ° C. for about 2 hours to dissolve. This solution is cooled to 28 ° C., 200 g of 35% by weight hydrochloric acid and 110 g of n-butyraldehyde are added, the liquid temperature is lowered to 15 ° C., and the acetalization reaction is carried out while maintaining this temperature. Precipitated. Thereafter, the liquid temperature was kept at 30 ° C. for 5 hours to complete the reaction, and a white powder of polyvinyl acetal resin was obtained through neutralization, washing with water and drying.
The obtained polyvinyl acetal resin was dissolved in DMSO-d ₆ (dimethylsulfoxide), and the degree of acetalization (degree of butyralization) was measured using ¹³ C-NMR (nuclear magnetic resonance spectrum). The (butyralization degree) was 38 mol%. Moreover, since the hydroxyl value of the used polyvinyl alcohol resin is 98 mol%, the hydroxyl group remaining after the acetalization reaction of the obtained polyvinyl acetal resin is 60 mol%.

(Synthesis of methacrylic resin)
In a 2 L separable flask equipped with a stirrer, a cooler, a thermometer, a hot water bath, and a nitrogen gas inlet, 30 parts by weight of methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (2-HEMA) (of a homopolymer) (Tg 55 ° C.) 70 parts by weight, mercaptopropanediol as a chain transfer agent, and 100 parts by weight of 1,2-ethanediol as a solvent were mixed to obtain a monomer mixture.

The obtained monomer mixture was bubbled with nitrogen gas for 20 minutes to remove dissolved oxygen, and then the temperature inside the separable flask system was replaced with nitrogen gas and heated until the hot water bath boiled with stirring. A solution obtained by diluting the polymerization initiator with ethyl acetate was added. During the polymerization, an ethyl acetate solution containing a polymerization initiator was added several times.

Seven hours after the start of polymerization, the polymerization was terminated by cooling to room temperature. Thereby, a 1,2-ethanediol solution of methacrylic resin was obtained. When the obtained polymer was analyzed by gel permeation chromatography using a column LF-804 manufactured by SHOKO as a column, the weight average molecular weight in terms of polystyrene was as shown in Table 4.
To the 1,2-ethanediol solution of the methacrylic resin thus obtained, 1,2-ethanediol was further added so as to have the composition ratio shown in Table 4, and the binder was dispersed by a high-speed disperser. A resin composition was prepared.

Table 4 shows BL-9EX (manufactured by Nikko Chemical Co., Ltd.) as a nonionic surfactant and low melting glass fine particles ABX-169F (manufactured by Tocan Material Technology) as a glass powder with respect to the obtained polyvinyl acetal resin and methacrylic resin. It added so that it might become the described composition ratio, it knead | mixed enough using the high-speed stirring apparatus, it processed until it reached | attained the smooth state with the 3 roll mill, and produced the glass paste.

(Examples 9 to 10)
The same as Example 1 except that the composition ratio of methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (2-HEMA) was changed to the composition ratio of Table 4 and the addition amount of the chain transfer agent was adjusted. Polymerization was carried out to obtain a methacrylic resin. The weight average molecular weight was as shown in Table 4.
Moreover, the addition amount of n-butyraldehyde, reaction temperature, and reaction time were adjusted, and reaction-neutralization-drying was performed in the same manner as in Example 8 to obtain a polyvinyl acetal resin. The hydroxyl value of the polyvinyl alcohol used was 98 mol%, and the degree of polymerization was as shown in Table 4. Moreover, the hydroxyl value of the obtained polyvinyl acetal resin was as shown in Table 4.
Each component was adjusted so that it might become the composition ratio of Table 4, and it carried out similarly to Example 8, and produced the binder resin composition and the glass paste.

(Comparative Example 5)
A binder resin composition and a glass paste were prepared in the same manner as in Example 9 except that the solvent was changed to terpineol.

<Evaluation>
The binder resin composition obtained in Examples 8 to 10 and Comparative Example 5 and the glass paste were evaluated in the same manner as in Examples 1 to 7 and Comparative Examples 1 to 3. The results are shown in Tables 4-5.

As a result of adding the polyvinyl acetal resin, all evaluations showed good results. Especially during sandblasting, a significant reduction in cutting time was confirmed.
In Comparative Example 5, since terpineol was used as a solvent, cracks were observed in the dielectric precursor layer in the evaluation of the sheet attack resistance, and there was a region where cutting could not proceed to the lower part of the glass rib precursor in the sandblasting evaluation. It was.

(Examples 11 to 12)
As in Example 8, the polymerization solution was adjusted using the same composition ratio of methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (2-HEMA) as in Example 8, and the addition amount of the chain transfer agent was adjusted. Polymerization was carried out to obtain a methacrylic resin. The weight average molecular weight was as shown in Table 6.
The addition amount of n-butyraldehyde, reaction temperature, and reaction time were adjusted, and reaction-neutralization-drying was performed in the same manner as in Example 8 to obtain a polyvinyl acetal resin. The hydroxyl value of the polyvinyl alcohol used was 98 mol%, and the degree of polymerization was as shown in Table 6. Moreover, the hydroxyl value of the obtained polyvinyl acetal resin was as shown in Table 6. Using the obtained polyvinyl acetal resin, each component was adjusted so that the composition ratio shown in Table 6 was obtained, and a polyvinyl acetal resin was obtained in the same manner as in Example 8.
Each component was adjusted so that it might become the composition ratio of Table 6, and it carried out similarly to Example 8, and produced the binder resin composition and the glass paste.

(Comparative Example 6)
The addition amount of n-butyraldehyde, reaction temperature, and reaction time were adjusted, and reaction-neutralization-drying was performed in the same manner as in Example 8 to obtain a polyvinyl acetal resin. The hydroxyl value of the polyvinyl alcohol used was 98 mol%, and the degree of polymerization was as shown in Table 6. Moreover, the hydroxyl value of the obtained polyvinyl acetal resin was as shown in Table 6. Using ethyl cellulose STD100 (manufactured by Sigma-Aldrich) as a binder resin and the obtained polyvinyl acetal resin, each component was adjusted to the composition ratio of Table 6, and the binder resin composition was obtained in the same manner as in Example 8. A glass paste was prepared.

<Evaluation>
The following evaluation was performed about the binder resin composition obtained in Examples 11-12 and Comparative Example 6, and a glass paste. The results are shown in Tables 6-7.

(3) Sheet Attack Resistance The glass paste prepared in Examples 11 to 12 and Comparative Example 6 was coated on a glass substrate (2 cm × 5 cm) using an applicator set to 10 mil. Curing was performed in a 120 ° C. oven for 30 minutes to evaporate the solvent contained in the paste, thereby forming a dielectric precursor layer. Thickness was 10 microns and it was dense, and the coated surface of the glass paste was smooth.
A binder resin composition containing no surfactant and glass powder, prepared in the same manner as in Comparative Example 6, was applied onto the dielectric precursor layer using an applicator set to 5 mils. Curing was performed in a 120 ° C. oven for 30 minutes to evaporate the solvent component, and the state of the dielectric precursor layer was observed with a microscope. The case where a hole was found in the dielectric precursor layer was marked as x, and the case where there was no change was marked as ◯.

(4) Rib surface property, sand blasting property The glass paste produced in Examples 11 to 12 and Comparative Example 6 was coated on a glass substrate (2 cm × 5 cm) using an applicator set to 10 mils. Curing was performed in a 120 ° C. oven for 30 minutes to evaporate the solvent contained in the glass paste, thereby forming a dielectric precursor layer. Thickness was 10 microns and it was dense, and the coated surface of the glass paste was smooth.
A glass paste prepared in the same manner as in Comparative Example 6 was coated on the dielectric precursor layer, then formed into a thickness of 400 microns with a knife coater, dried in an oven at 120 ° C. for 1 hour, and a glass rib precursor with a thickness of 180 microns was formed. Molded.
A dry film resist for sandblasting (manufactured by Tokyo Ohka Kogyo Co., Ltd., BF603) was laminated at 50 ° C. on the glass rib precursor, an exposure mask was set, and exposure was performed at 300 mJ / cm ² . Development was performed with a 0.2% aqueous sodium carbonate solution to form a line and space pattern having a width of 100 microns.
The case where the adhesion of the dry film resist on the glass rib precursor was good was designated as rib surface property ◯, and the case where fine bubbles did not escape was designated as rib surface property x.
Using a sandblasting machine (Pneuma Blaster SCM-1ADE-NE-401) manufactured by Fuji Seisakusho on the surface on which the pattern was formed, an abrasive (S4 # 1000 manufactured by Fuji Seisakusho) was sprayed at an ejection pressure of 0.15 MPa to perform sandblasting. went.
When the cutting progresses promptly and there is no problem with the rib shape, ◎, when the cutting progresses to the dielectric precursor layer, ◯ when the dry film resist is peeled off before the cutting is finished, and cutting to the bottom When X did not advance, it was set as x.

As a result of using the glass paste obtained for the dielectric precursor layer, all the evaluations in Examples 11 to 12 show good results, and there is no migration of the resin component between the dielectric precursor layer and the glass rib precursor. Sex did not cause a problem.
In Comparative Example 6, since terpineol was used as the solvent, cracks were observed in the dielectric precursor layer in the evaluation of the sheet attack resistance, and a region where cutting could not proceed to the lower part of the glass rib precursor was also generated in the evaluation of the sandblasting property. .

(Example 13)
(Methacrylic resin synthesis)
In a 2 L separable flask equipped with a stirrer, cooler, thermometer, hot water bath and nitrogen gas inlet, 100 parts by weight of methyl methacrylate (MMA), mercaptopropanediol as a chain transfer agent, and 50 parts by weight of propylene carbonate as a solvent Were mixed to obtain a monomer mixture.

The obtained monomer mixture was bubbled with nitrogen gas for 20 minutes to remove dissolved oxygen, and then the temperature inside the separable flask system was replaced with nitrogen gas and heated until the hot water bath boiled with stirring. A solution obtained by diluting the polymerization initiator with ethyl acetate was added. During the polymerization, an ethyl acetate solution containing a polymerization initiator was added several times.

Seven hours after the start of polymerization, the polymerization was terminated by cooling to room temperature. Thereby, a propylene carbonate solution of a methacrylic resin was obtained. When the obtained polymer was analyzed by gel permeation chromatography using a column LF-804 manufactured by SHOKO as a column, the weight average molecular weight in terms of polystyrene was as shown in Table 8.
Propylene carbonate was further added to the propylene carbonate solution of the methacrylic resin thus obtained so as to have the composition ratio shown in Table 8, and dispersed with a high speed disperser to prepare a binder resin composition.

With respect to the binder resin composition, BL-2 (manufactured by Nikko Chemical Co., Ltd.) as a nonionic surfactant, and low melting point glass fine particles ABX-169F (manufactured by Tokan Material Technology Co., Ltd.) as glass powders in the composition ratio described in Table 8 Then, the mixture was sufficiently kneaded using a high-speed stirrer and processed until it reached a smooth state with a three-roll mill to produce a glass paste.

(Example 14)
Polymerization was carried out in the same manner as in Example 13 except that the chain transfer agent was changed to mercaptosuccinic acid and the addition amount was adjusted to obtain a propylene carbonate solution of a methacrylic resin. The weight average molecular weight was as shown in Table 8. Each component was adjusted so that it might become the composition ratio of Table 8, and it carried out similarly to Example 13, and produced the binder resin composition and the glass paste.

(Comparative Example 7)
Polymerization was carried out in the same manner as in Example 13 except that terpineol was used as the solvent, the chain transfer agent was changed to dodecyl mercaptan, and the addition amount was adjusted to obtain a terpineol solution of methacrylic resin. The weight average molecular weight was as shown in Table 8. Each component was adjusted so that it might become the composition ratio of Table 8, and it carried out similarly to Example 13, and produced the binder resin composition and the glass paste.

<Evaluation>
The binder resin composition obtained in Examples 13 to 14 and Comparative Example 7 and the glass paste were evaluated in the same manner as in Examples 1 to 7 and Comparative Examples 1 to 3. The results are shown in Tables 8-9.

As a result of adding the polyvinyl acetal resin, all evaluations showed good results. Moreover, since the polymer terminal of the methacrylic resin was modified with a polar group, the adhesion to the substrate and the dry film resist was good even if the amount of the binder resin was reduced. Especially during sandblasting, a significant reduction in cutting time was confirmed.
For Comparative Example 7, terpineol was used as the solvent to increase the resin molecular weight and the binder resin amount was reduced, but in the evaluation of the sheet attack resistance, cracks were seen in the dielectric precursor layer, and the substrate and dry film resist were peeled off. In the sandblasting evaluation, rib shape collapse was observed.

(Example 15)
The glass paste produced in Example 8 was coated on a glass substrate using an applicator set to 10 mil on a glass substrate (2 cm × 5 cm). Curing was performed in a 120 ° C. oven for 30 minutes to evaporate the solvent contained in the paste, thereby forming a dielectric precursor layer containing a methacrylic resin and a polyvinyl acetal resin. Thickness was 10 microns and it was dense, and the coated surface of the glass paste was smooth. A 10% by weight ethyl cellulose (STD46) solution of terpineol was applied onto the dried dielectric precursor layer using an applicator set to 13 mils, and dried in an oven at 120 ° C. for 30 minutes.

(Example 16)
(Methacrylic resin synthesis)
In a 2 L separable flask equipped with a stirrer, cooler, thermometer, hot water bath, and nitrogen gas inlet, 100 parts by weight of 2-hydroxyethyl methacrylate (2-HEMA), mercaptopropanediol as a chain transfer agent, as a solvent 100 parts by weight of 1,2-ethanediol was mixed to obtain a monomer mixture.

The obtained monomer mixture was bubbled with nitrogen gas for 20 minutes to remove dissolved oxygen, and then the temperature inside the separable flask system was replaced with nitrogen gas and heated until the hot water bath boiled with stirring. A solution obtained by diluting the polymerization initiator with ethyl acetate was added. During the polymerization, an ethyl acetate solution containing a polymerization initiator was added several times.

Seven hours after the start of polymerization, the polymerization was terminated by cooling to room temperature. Thereby, a 1,2-ethanediol solution of methacrylic resin was obtained. When the obtained polymer was analyzed by gel permeation chromatography using a column LF-804 manufactured by SHOKO as a column, the weight average molecular weight in terms of polystyrene was as shown in Table 10.
To the 1,2-ethanediol solution of the methacrylic resin thus obtained, 1,2-ethanediol was further added so that the composition ratio shown in Table 10 was obtained, and the binder was dispersed by a high-speed disperser. A resin composition was prepared.

Table 10 shows BL-9EX (manufactured by Nikko Chemical Co., Ltd.) as a nonionic surfactant and low melting point glass fine particles ABX-169F (manufactured by Tokan Material Technology Co., Ltd.) as glass powders with respect to the obtained binder resin composition. It added so that it might become a composition ratio, fully knead | mixed using the high-speed stirring apparatus, it processed until it reached the smooth state with the 3 roll mill, and produced the glass paste. The obtained glass paste was applied and dried to form a dielectric precursor layer in the same manner as in Example 15, and an ethylcellulose solution was applied and dried.

(Comparative Example 8)
A 10% by weight solution of terpineol in ethylcellulose (STD46) was prepared, and each component was adjusted so as to have the composition ratio shown in Table 10, and a binder resin composition and a glass paste were prepared in the same manner as in Example 1.
Using this glass paste, a dielectric precursor layer was formed in the same manner as in Example 15, and an ethylcellulose solution was applied.

<Evaluation>
The state of the dielectric precursor layer of the glass substrate coated with the dielectric precursor layer obtained in Examples 15 to 16 and Comparative Example 8 is transmitted through the back using a microscope to check for cracks and voids. Observed. Moreover, the glass substrate was cut | disconnected so that the lamination | stacking cross section of a dielectric material precursor layer and an ethylcellulose resin layer might appear, and the cross section between a dielectric material precursor layer and an ethylcellulose resin layer was observed with the microscope.
The results are shown in Tables 10 to 11.

In the glass substrates with dielectric precursor layers obtained in Examples 15 to 16, the ethylcellulose resin layer and the glass powder layer were dense, and no voids or cracks were observed. Moreover, in the cross-sectional observation, the boundary line between the dielectric precursor layer and the ethyl cellulose resin layer was clear and the boundary surface disappeared. Further, no peeling or the like was observed on the cross section of the dielectric precursor layer and the ethyl cellulose resin layer, and the adhesion was good.
In Comparative Example 8 in which ethyl cellulose resin was used for the dielectric precursor layer, cracks occurred in the dielectric precursor layer when observed from the back side, and the boundary between the dielectric precursor layer and the ethyl cellulose resin layer was observed when the cut surface was observed. The lines were unclear and it was observed that the ethylcellulose resin swelled the dielectric precursor layer.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the glass paste which can manufacture a plasma display panel efficiently, and this plasma paste using this glass paste can be provided.

Claims (9)

At least a (meth) acrylic resin comprising a monomer having a glass transition temperature (Tg) of 20 ° C. or higher, a glass powder, a specific gravity of 0.95 to less than 1.35, and a boiling point of 140 ° C. to 300 ° C. A glass paste containing a solvent having a temperature of less than ° C. The glass paste according to claim 1, wherein the (meth) acrylic resin has a weight average molecular weight of 5,000 to 200,000 in terms of polystyrene. The glass paste according to claim 1 or 2, wherein the solvent has a dielectric constant of 25 or more. The solvent is at least one selected from the group consisting of propylene carbonate, γ-butyrolactone, 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, and 1,4-butanediol. The glass paste according to claim 1, 2, or 3. Furthermore, polyvinyl acetal resin is contained, The glass paste of Claim 1, 2 or 3 characterized by the above-mentioned. The glass paste according to claim 5, wherein the polyvinyl acetal resin has a hydroxyl value of 40 mol% or more and a weight average molecular weight in terms of polystyrene of 5,000 to 100,000. The solvent is at least one selected from the group consisting of 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, and 1,4-butanediol. Item 7. A glass paste according to item 5 or 6. A dielectric precursor layer forming step for forming a dielectric precursor layer by applying a dielectric layer paste containing cellulose resin as a main component on a back glass substrate and drying the dielectric layer, and the dielectric without performing a degreasing step A glass rib precursor forming step of forming a glass rib precursor by coating the glass paste according to claim 1, 2, 3, 4, 5, 6 or 7 on the surface of the precursor layer and drying the glass paste, and the glass rib by sandblasting. A method for manufacturing a plasma display panel, comprising: a concave shape forming step for forming a concave shape on a precursor; and a degreasing / firing step for heating and degreasing / firing the dielectric precursor layer and the glass rib precursor. . A dielectric precursor layer forming step of forming a dielectric precursor layer by applying the glass paste according to claim 1, 2, 3, 4, 5, 6 or 7 on a back glass substrate and drying the substrate, and a degreasing step A glass rib precursor forming step of forming a glass rib precursor by applying a glass rib paste containing cellulose resin as a binder main component on the surface of the dielectric precursor layer without drying, and sandblasting the glass rib precursor. A method for manufacturing a plasma display panel, comprising: a concave shape forming step for forming a concave shape on the surface; and a degreasing / firing step for heating and degreasing / firing the dielectric precursor layer and the glass rib precursor.