JP2001139824A - Paste for calcination - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paste for calcination used in forming a rib on a substrate by a sand blasting method in which viscosity reduction of the paste, which will occur when ground rib frit is reutilized, can be improved so as to make it possible to reutilize the ground rib frit by re-pasting it. SOLUTION: A paste for calcination comprises at least a glass powder having a low melting point, a resin and a solvent, wherein the resin component as a binder has a number average molecular weight (Mn) of not more than 30,000. In forming a rib 3 by a sand blasting method with use of the paste, thermally induced resin degradation does not occur when the paste is coated and dried, and therefore, viscosity reduction of the paste, which will occur when ground rib frit is reutilized, can be improved. Consequently, as the ground rib frit can be reutilized by re-pasting it, an environmental problem due to the disposal of waste materials generated by sand blasting can be obviated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a firing paste used for forming ribs on a substrate such as a plasma display panel or a plasma addressed liquid crystal display by a sandblast method.

[0002]

2. Description of the Related Art Generally, a plasma display panel (hereinafter, referred to as a PDP) is provided with a pair of regularly arranged electrodes on two opposing glass substrates, and an N-electrode therebetween.
It has a structure in which a gas mainly composed of e, Xe or the like is sealed. Then, a voltage is applied between these electrodes, and a discharge is generated in minute cells around the electrodes, so that each cell emits light and display is performed. In order to display information, regularly arranged cells are selectively caused to emit light. This PDP has a direct current type (DC type) in which electrodes are exposed to the discharge space and an alternating current type (AC type) in which electrodes are covered with an insulating layer.
Type), both of which are further classified into a refresh driving method and a memory driving method according to the difference in display function and driving method.

FIG. 1 shows a configuration example of an AC type PDP. This figure shows the front plate and the back plate separated from each other. As shown in the figure, two glass substrates 1 and 2 are arranged in parallel and opposed to each other, and both become the back plate. The ribs 3 provided on the glass substrate 2 in parallel with each other are held at regular intervals. On the back side of the glass substrate 1 serving as a front plate, composite electrodes composed of a sustain electrode 4 which is a transparent electrode and a bus electrode 5 which is a metal electrode are formed in parallel with each other, and a dielectric layer 6 is covered thereover. The protective layer 7 (MgO layer) is further formed thereon. On the front side of the glass substrate 2 serving as the back plate, address electrodes 8 are formed between the ribs 3 so as to be orthogonal to the composite electrodes and are formed in parallel with each other. Are formed, and a phosphor 10 is provided so as to cover the wall surface of the rib 3 and the cell bottom surface. This AC type PDP is of a surface discharge type, and has a structure in which an AC voltage is applied between composite electrodes on the front panel to discharge. Then, the phosphor 10 emits light by the ultraviolet light generated by the discharge, so that an observer can visually recognize the light transmitted through the front plate.

[0004] The ribs in the above-mentioned PDP are made of low melting glass in which a metal oxide such as alumina is dispersed. To form the ribs, pattern printing is performed using a paste obtained by kneading a low-melting glass powder, an inorganic filler powder (filler), a resin solution dissolved in a solvent, and the like. After forming a rib forming material layer by processing and drying, laminating a photosensitive resist called a dry film on it, performing exposure and subsequent development to form a resist pattern, and removing unnecessary parts by sandblasting The rib forming layer is patterned by the method described above. Then, after the rib forming layer is patterned in this way, the resin and the solvent are removed by burning through a firing furnace, and the rib is formed by melting the low melting point glass powder.

[0005]

The method of forming ribs by the above-mentioned sand blast method is excellent in that good line width accuracy can be obtained, but has a disadvantage that a large amount of ground rib frit is generated. ing. Therefore, it is desired to reuse the ground rib frit from the viewpoint of cost and environmental problems. Regarding reuse, it is necessary to first separate the sandblasted abrasive and the ground rib frit, but in this regard, the air separator is classified by the cyclone attached to the blasting device, and then the grinding is performed by using a further classification device. Only the rib frit obtained can be extracted. However, when making a slight composition adjustment to the extracted rib frit, re-dissolving in a solvent and re-pasting, if the paste is made with the same solid content ratio as the new paste, the paste becomes considerably lower in viscosity than the new paste. Process, such as coating, must be changed. In addition, apart from this problem, in the rib formation by the sand blast method, the substrate was washed with shower water after sand blasting, and then the dry film was peeled off by applying an alkali solution, and the purpose was to further remove alkali components. A process such as shower water washing is required. In any of these steps, a part of the rib is removed or falls down due to weak adhesion or penetration of water.

[0006] When the paste is prepared with the same solid content ratio as the new paste when re-pasting with the extracted rib frit, the reason for the paste having a considerably lower viscosity than the new paste is that the contained resin component is It is conceivable that a heat treatment of about 150 ° C. was performed when the paste was applied and dried, resulting in thermal deterioration. Specifically, the deterioration is caused by a decrease in the molecular weight of the resin component. If the viscosity of the paste fluctuates a little (about ± 20%), it is possible to cope with it. Even if the measures can be taken, problems remain from the viewpoint of stabilizing the process.

[0007]

In order to solve the above problems, the present invention uses a low molecular weight type resin component as a resin component of a firing paste for forming ribs. A resin having good compatibility and excellent in toughness, heat stability and alkali resistance when formed into a film is to be used. If ribs are formed by sandblasting using a paste containing such a resin as a component, resin deterioration (decrease in molecular weight) does not occur when the coating film is dried, and thus occurs when the ground rib frit is reused. The viscosity reduction of the paste is improved. In addition, even when a paste in which the ground rib frit is reused is used, a part of the rib is not chipped or falls during washing with water or immersion in an alkaline solution.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The firing paste according to the present invention comprises:
A firing paste comprising at least a low-melting glass powder, a resin, and a solvent, wherein the resin component as a binder has a number average molecular weight (Mn) of 30,000 or less. That is, the number average molecular weight (Mn) is 30
When using a resin that exceeds 000 for the binder,
When the paste is applied and dried, the resin undergoes thermal deterioration and the viscosity relatively decreases, but the number average molecular weight (M
In a paste using a resin having n) of 30,000 or less as a binder, the rate of causing thermal deterioration when coating and drying is small, and the viscosity does not decrease so much.

Conventional baking pastes mainly use ethyl cellulose (“STD100” (Mn)) as a binder.
= 68000)). This "STD100"
In order to see the change in viscosity due to heat, when heat-treated at 150 ° C. and then frit was added to make a paste, the viscosity in the paste evaluation was compared to that obtained by adding a frit to the non-heat-treated “STD100” and pasting. Is 96 Pas
→ It decreases to 76 Pas (-20.8%). Since the degree of this change is large, the coating conditions change. Therefore, "STD10" (Mn = 27000), which is ethyl cellulose having a number average molecular weight of 30,000 or less, and "STD10"
For "4" (Mn = 14000), the change in viscosity due to heat under the same conditions is as follows. The viscosity in the paste evaluation is 96 Pas → 82 Pas (−14.5%) and 96 Pas, respectively.
s → 90 Pas (-0.06%), which is a small decrease, and it is not necessary to change the coating conditions for such a change in viscosity.

As the resin for the binder used in the firing paste of the present invention, cellulose derivatives such as ethylcellulose, hydroxypropylcellulose, methylcellulose, nitrocellulose, cellulose acetate and cellulose butyrate are suitable. , Polyvinyl butyral resin, various acrylic resins, or polyester resins (for example, alkyd resins) can also be used.

It is desirable to use ethyl cellulose among the above resins. Ethyl cellulose is classified into three types, STD (standard), MED (medium), and HE (high ethoxy), depending on the content of ethoxy groups contained in the molecule. Further, each type has a variety exhibiting various viscosities. For example, “STD100” indicates that it is a standard type ethyl cellulose having a viscosity of 100 cps. Table 1 shows the features of each type. From Table 1, it can be seen that STD type and MED type are selected as the paste binder in view of the toughness, tensile strength, hardness and abrasion resistance of the film. On the other hand, the ethoxy group content of each type is 48-49.5% for the STD type, 45-46.5% for the MED type, and HE
The type is 49.5 to 52%, and considering this and Table 1, the content of the ethoxy group (—OC ₂ H ₅ ) is 49.
It can be seen that it is preferable to use 5% or less of ethyl cellulose.

[0012]

[Table 1]

The low-melting glass powder used in the paste functions as a binder constituting the ribs in the fired ribs, and its glass transition point (Tg) is determined by the fact that the resin in the paste is completely fired. The softening point of the low melting glass powder must be lower than the temperature at which the glass of the substrate is deformed when ribs are formed using glass as a substrate. Usually, the glass transition point of the low melting glass powder is 350 to 500 ° C, and the softening point is 400 to 600 ° C.

When the low melting glass powder in the firing paste of the present invention uses a lead-based glass powder, it can contain at least the following composition. (1) Lead oxide: 35 to 60% by weight (2) Silicon oxide: 5 to 25% by weight (3) Boron oxide: 13 to 10% by weight

When a low-melting glass powder in the firing paste of the present invention is a lead-free glass powder, it may contain at least the following composition. (1) Boron oxide: 1 to 15% by weight (2) Zinc oxide: 15 to 35% by weight (3) Bismuth oxide: 5 to 25% by weight

In any of the low melting point glass powders, if each component is out of the above range, it cannot be used as a rib paste for PDP. That is, when the amount is small, the softening point becomes high and the softening point is not softened at the sintering temperature.

The solvent used for the paste is preferably a solvent having a high boiling point from the viewpoint of handling. Terpenes such as α-, β- or γ-terpineol, ethylene glycol monoalkyl ethers, ethylene glycol dialkyl ethers , Diethylene glycol monoalkyl ethers, diethylene glycol dialkyl ethers, ethylene glycol monoalkyl ether acetates, ethylene glycol dialkyl ether acetates, diethylene glycol monoalkyl ether acetates, diethylene glycol dialkyl ether acetates, propylene glycol monoalkyl ethers, propylene glycol dialkyl Ethers, propylene glycol monoalkyl ether acetates, propylene glycol Call dialkyl ether acetates, methanol, ethanol, isopropanol, 2-ethylhexanol, alone alcohol such as 1-butoxy-2-propanol, or optionally used in combination of two or more kinds selected.

The above-mentioned resin and high-boiling-point solvent are selected in consideration of solubility and dissolved to form a resin solution, in which various additives and powdery particles are dissolved or dispersed.
Paste.

It is preferable to add a dispersion stabilizer to the firing paste of the present invention. As the dispersion stabilizer, a polycarboxylic acid (aliphatic polycarboxylic acid) or a salt thereof, a phosphoric acid ester, a polyamide amide phosphoric acid or a salt thereof, or a salt of a polyamide amide and a polymer acid polyester is suitable. Among them, a surfactant containing a phosphate ester as a main component is particularly preferable in terms of imparting fluidity suitable for application to the paste and improving storage stability.

To the firing paste of the present invention, a metal powder, a metal oxide powder, a conductive substance powder, a dielectric powder, a pigment, and the like can be added as required according to the application.

Among them, the metal oxide powder can be used as an aggregate. The aggregate plays a role in maintaining the shape and strength of the ribs formed by firing. For example,
Zircon, zirconia, alumina, titania, silica,
There are oxide or non-oxide ceramics such as titanium oxide, magnesia, mullite, cordierite (or cordierite), silicon carbide, aluminum nitride, and barium titanate. Glass also serves as an aggregate.

As the metal powder, aluminum powder used for forming a cathode on a front plate of a plasma display panel, ruthenium used for forming a rib electrode on a back plate, and the like are used. As the conductive substance powder, gold,
Metal powders such as silver, copper, chromium, nickel, and aluminum, In ₂ O ₃ / Sn, ZnO / Al, TiO _x , K ₂
There is a conductive inorganic oxide such as O.TiO _x or SnO ₂ / Sb. The dielectric powder can be properly used depending on the size of the dielectric, and includes inorganic oxides such as titania, alumina, and zirconia.

In the firing paste of the present invention, a coloring agent may be positively added for the purpose of coloring. In this case, since it is desirable to have heat resistance at a temperature higher than the firing temperature, an inorganic pigment is usually used. As the pigment, a composite oxide-based pigment composed of oxides of two or more metals (metals such as Cu, Co, Ni, Fe, Mn,
Cu, Sb, As, Bi, Ti, Cd, Al, Ca, S
Two or more kinds are selected from i, Mg, Ba and the like. ), Titanium oxide, alumina, silica, magnesia,
Lead titanate, potassium titanate, cadmium sulfate selenide, red iron oxide (Fe ₂ O ₃ ), cuprous oxide, cadmium mercury red (CdS + HgS), chrome vermilion, silver vermilion, antimony red, iodine red, zinc iron red, molybdenum Red, lead red, cadmium red, chrome green, zinc green, cobalt green, chromium oxide, viridian, emerald green ultramarine, navy blue, cobalt blue, cerulean blue, copper sulfide, titanium yellow, titanium black,
Black iron oxide (Fe ₃ O ₄ ), yellow iron oxide, cadmium yellow, or graphite can be used, and is appropriately selected and used according to the purpose.

No coupling agent such as a silane coupling agent is added to the firing paste of the present invention. That is, the rib fall can be prevented by increasing the resin content in the paste. If such an additive is added, the effect is lost due to heat, so that it must be newly added at the time of repasting. Then, the inorganic component (Si), including the thermal degradation component, increases each time the material is regenerated, but if it increases, the debris increases and the composition changes.

The firing paste of the present invention is particularly suitably used when forming ribs on the back plate of a plasma display panel by a sandblast method. Specifically, the method comprises applying the firing paste according to the present invention to a substrate, drying the applied paste, laminating a dry film thereon, and performing pattern exposure and subsequent development to obtain a desired rib. Form a mask for the pattern, then
After the portion where the mask is not formed is ground by sandblasting, the mask is removed, and then the substrate is baked.

The grinding powder generated during the sand blasting process is collected, separated by an air separator by a cyclone attached to the blasting device, and then separated into abrasive and ground rib frit by using a further classifying device. At the time of re-pasting using the rib frit, since fine powder of an abrasive is mixed in the rib frit, the composition is adjusted and reused for producing a re-paste. In this case, the resin is already mixed in the rib frit, so not only the composition adjustment but also the re-pasting is performed.
It is also necessary to adjust the amount of resin. Therefore, the method of producing the re-paste is different from a new one, in which a vehicle with insufficient components and a corresponding diluent solvent are mixed into a resin-mixed frit to form a paste, and then a new paste is mixed at a predetermined ratio.
Since the re-paste thus produced hardly undergoes thermal deterioration of the resin component, the viscosity of the re-paste is less reduced than that of a new paste, and can be used without changing processes such as coating.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to a series of steps for forming high-definition ribs on a PDP substrate.

(Embodiment 1) The planar size is 1000 ×
A glass substrate having a thickness of 600 mm and a thickness of 2.8 mm is prepared, and a large number of parallel striped electrodes are formed on one surface by screen printing at intervals of 150 μm.
Then, the entire surface on the electrode side of the glass substrate is collectively coated with a firing paste having the following composition A by a die coater, dried at 150 ° C. for 30 minutes and solidified to form a rib-forming material layer.

<Composition A>-100 parts by weight of glass frit ("RFB024D1" manufactured by Asahi Glass Co., Ltd.)-14 parts by weight of inorganic filler ("Sumikorantam AA-07" manufactured by Sumitomo Chemical Co., Ltd.)-Pigment ( 11 parts by weight (Daiichi Seikagaku Kogyo Co., Ltd. “Thai Peroxysite Frac # 9510”) ・ Ethyl cellulose 2 parts by weight (Nissin Kasei Co., Ltd. “Ethocel MED100”) ・ Terpineol 21 parts by weight ・Diethylene glycol monobutyl ether acetate 21 parts by weight

Next, a dry film ("Audil BF60" manufactured by Tokyo Ohka Kogyo Co., Ltd.) is formed on the entire surface of the rib forming material layer.
3)), exposure and subsequent development,
A patterned resist layer is formed on the rib forming material layer as a sandblast mask. As the developing solution, a 0.2% aqueous solution of sodium carbonate is used. Note that the pattern of the resist layer of the present example has a parallel stripe shape with a width of 50 μm and an interval of 100 μm, and the electrode on the surface of the glass substrate is located almost in the center between the intervals of 100 μm between the resist layers. Placed.

Subsequently, the ribs are patterned by a sandblasting process. Specifically, the substrate is transported over a number of transport rollers and is loaded into the blasting chamber. Then, an abrasive (brown fused alumina # 400) is ejected from the ejection nozzle toward the rib-forming material layer and the resist layer side of the workpiece in which the rib-forming material layer and the resist layer are formed on the surface of the substrate, that is, the glass substrate. Pressure 3kg / m ²
Inject with. Eight injection nozzles are provided that are capable of reciprocating in a direction perpendicular to the direction of transport of the workpiece. Each spray nozzle is a diffusion-type spray nozzle, which diffuses the abrasive shape of the abrasive three times as much as usual. Even if the blast processing speed is increased by the combination of the substrate transfer speed and the moving speed of each spray nozzle, Processing uniformity can be maintained. In the processing chamber, an abrasive is sprayed together with the air to the resist layer and the rib forming material layer side of the glass substrate to grind and remove the rib forming material layer in a portion other than the rib forming material layer immediately below the resist layer. To form ribs. The rib thus formed has a width of 50 μm and a height of 150 μm.
m, the spacing between each rib is 100 μm.

The abrasive sprayed from the spray nozzle toward the substrate becomes a mixed powder with the grinding powder of the rib forming material, falls into a hopper below the blasting chamber, and is generated in the conduit from the lower end of the hopper. Transported to the separation tank in the air stream. Then, in this separation tank, the 1
Foreign matter having a size of 00 μm or more is removed, and then sent to the cyclone via a communication pipe. The air flow in the blasting chamber is generated by suction of air by a blower of a dust collector. That is, the airflow flows sequentially to the hopper, the conduit, the separation tank, the communication pipe, the cyclone, and the dust collector.

FIG. 2 is a schematic configuration diagram showing an example of a cyclone and a dust collecting device incorporated in the step of collecting the rib forming material. The mixed powder that has fallen from the blasting chamber to the hopper and has a foreign matter having a size of 100 μm or more removed in the separation tank is transported to the cyclone 12 through the communication pipe 11. In the cyclone 12, the reusable abrasive and the dust composed of the crushed abrasive and the pieces of the rib-forming material ground from the substrate are classified. The reusable abrasive stays in the distributor 13 below the cyclone 12, while the dust rises in the center of the cyclone 12 by airflow and passes through the duct 14 communicating with the upper center. 1
The dust is collected by the dust collector 15 and the clean air is discharged to the atmosphere by the blower 16. The abrasive remaining in the distributor 13 below the cyclone 12 is collected in an abrasive tank 17 connected to the lower end of the cyclone.
8 again. The abrasive is drawn by the compressed air in the nozzle portion and is ejected from the ejection nozzle 18 together with the compressed air.
In this way, the abrasive is injected from the injection nozzle 18 toward the substrate by repeating the above steps, and is subjected to blast processing.

In the dust collector 15, dust is attached to the surface of the filter 15a. Therefore, Cyclone 12
The valve 19 in the duct 14 between the dust collector 15 and the dust collector 15 is closed, and the valve 20 between the dust collector 15 and
Is switched to supply air, so that dust adhering to the surface of the filter 15a is dropped and collected in the lower tank 15b. The dust collected in the dust tank 21 of the dust collector 15 in this manner is a dry classifier (for example,
Using Hosokawa Micron's “Turboflex”, the powder is classified into coarse powder (reusable abrasive) and fine powder (abrasive powder and ground rib powder). Here, the separated coarse powder is reused as an abrasive, and the fine powder is adjusted in composition as described above and is recycled, so that powder (rib frit) made of pieces of the rib forming material ground from the substrate is removed. It can be collected reliably and reused.

After the completion of the sandblasting treatment, the substrate is washed with shower water, and then the sandblasting mask is sprayed off with a 1 wt% aqueous solution of sodium hydroxide. Further, alkali washing is performed by performing shower water washing. And finally, the workpiece with ribs formed on the surface of the glass substrate,
By gradually heating the low-melting glass to a temperature at which the low-melting glass is completely melted and the binder is incinerated, the low-melting glass constituting the rib and each binder of the resist are completely burned, and the low-melting glass is melted and fired. A rib is formed.

On the other hand, the rib frit extracted in the step of collecting the rib forming material is re-pasted. Specifically, a solvent (terpineol: butyl carbitol acetate = 1: 1) is added to the rib frit so as to have a solid content ratio similar to that of the composition A. Using this re-paste, the rib formation and the recovery of the rib formation material are performed in the same steps as described above.
Then, the cycle of the re-pasting and the rib formation using the paste is repeated three times.

(Example 2) A rib was formed in the same manner as in Example 1 except that the ethyl cellulose having the composition A was changed to "Ethocel STD4" manufactured by Nissin Kasei Co., Ltd., and then the recovered rib frit was repasted. And the cycle of rib formation were repeated three times.

(Comparative Example 1) A rib was formed in the same manner as in Example 1 except that the ethyl cellulose of the composition A was changed to "Ethocel STD100" manufactured by Nissin Kasei Co., Ltd., and then the recovered rib frit was re-pasted. And the cycle of rib formation were repeated three times.

Comparative Example 2 Ribs were formed in the same manner as in Example 1 except that ethyl cellulose having composition A was changed to "Ethocel HE100" manufactured by Nissin Chemical Co., Ltd., and then the recovered rib frit was repasted. And the cycle of rib formation were repeated three times.

The number average molecular weight and ethoxy group content of the resins used in Examples 1 and 2 and Comparative Examples 1 and 2, the state of the ribs finally formed, the change in the viscosity of the paste (process suitability), and the like. Table 2 shows the overall judgment.

[0041]

[Table 2]

In Example 1, rib falling could be prevented by reducing the ethoxy group content. In Example 2, the change in viscosity could be reduced by using a low molecular weight resin for the binder. Further, since the viscosity becomes low when the solid content is the same, the amount of the resin is increased to obtain a viscosity suitable for the process. As a result, the adhesive strength is improved and the rib can be prevented from falling down. Note that, as in Comparative Examples 1 and 2, the fact that the rib has fallen down and the viscosity (process suitability) is “x” may be used if the coating conditions are changed.

[0043]

As described above, the firing paste of the present invention is a firing paste composed of at least a low-melting glass powder, a resin and a solvent, and has a number average molecular weight (Mn) of a resin component as a binder. ) Is not more than 30,000, so that when a rib is formed by sandblasting using this paste, resin deterioration does not occur when the coating film is dried, and paste that occurs when the ground rib frit is reused. Since the decrease in viscosity is improved, the ground rib frit can be re-pasted and reused, thereby avoiding environmental problems caused by disposal of sandblast waste.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a plasma display panel in which a front plate and a back plate are separated from each other.

FIG. 2 is a schematic configuration diagram illustrating an example of a cyclone and a dust collecting device incorporated in a rib forming material collecting step.

[Explanation of symbols]

 1, glass substrate 3 rib 4 sustain electrode 5 bus electrode 6 dielectric tank 7 protection tank 8 address electrode 9 dielectric tank 10 phosphor 11 communication pipe 12 cyclone 13 distributor 14 duct 15 dust collector 15a filter 16 blower 17 grinding Material tank 18 Injection nozzle 19 Valve 20 Valve 21 Dust tank

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H01J 11/02 H01J 11/02 BF Term (Reference) 4G062 AA08 AA09 AA15 BB04 BB08 DA03 DA04 DB01 DC03 DC04 DD01 DE04 DE05 DF05 DF06 EA01 EA10 EB01 EC01 ED01 EE01 EF01 EG01 FA01 FA10 FB01 FC01 FD01 FE01 FF01 FG01 FH01 FJ01 FK01 FL01 GA03 GA04 GB01 GC01 GD01 GE01 HH01 HH03 HH05 HH07 H03 KKHJ KK MM10 MM12 NN32 PP13 PP14 PP16 4J002 AB011 AB031 DL006 EC037 ED027 EH157 FD206 FD207 5C027 AA09 5C040 FA01 FA04 FA07 GA03 GA09 GF02 GF18 GF19 JA15 JA17 KA14 MA30

Claims (6)

[Claims] 1. A baking paste comprising at least a low-melting glass powder, a resin and a solvent, wherein the resin component as a binder has a number average molecular weight (Mn) of 30,000.
A firing paste, characterized in that: 2. The firing paste according to claim 1, wherein the resin component is ethyl cellulose. 3. An ethoxy group content of the resin component is 49.5.
% Or less. 4. The firing paste according to claim 1, wherein the low melting glass powder contains at least the following composition. (1) Lead oxide: 35 to 60% by weight (2) Silicon oxide: 5 to 25% by weight (3) Boron oxide: 13 to 10% by weight 5. The firing paste according to claim 1, wherein the low melting point glass powder contains at least the following composition. (1) Boron oxide: 1 to 15% by weight (2) Zinc oxide: 15 to 35% by weight (3) Bismuth oxide: 5 to 25% by weight 6. The method according to claim 1, wherein the firing paste is applied to a substrate, dried, laminated with a dry film, and then subjected to pattern exposure and subsequent development. A desired rib pattern mask is formed, and then a portion where the mask is not formed is ground by a sandblast method, the mask is removed, and then the substrate is baked. Rib forming method.