JP4578489B2 - Method for manufacturing plasma display panel - Google Patents

Description

  The present invention relates to a method for manufacturing a plasma display panel (hereinafter abbreviated as PDP). More specifically, the present invention relates to a method for manufacturing a PDP in which a buffer layer is formed between a glass substrate and a partition wall in order to prevent the partition wall from peeling off when a high-definition partition wall is formed by firing.

  In recent years, plasma displays have attracted attention as large displays. PDPs are capable of high-speed display as compared with liquid crystal panels and are easy to increase in size, and thus have penetrated into fields such as OA equipment and public information display devices. Progress in the field of high-definition television is also highly expected. Accompanying such expansion of applications, a fine color PDP having a large number of display cells has attracted attention.

An example of the structure of an AC type PDP is shown in FIG. The PDP is configured by bonding a front plate and a back plate. In the front plate, a transparent electrode made of ITO or tin oxide is formed on the back surface of the glass substrate. A plurality of transparent electrodes are formed in a strip shape. A pulsed AC voltage of usually 10 kHz to several tens of kHz is applied between the adjacent transparent electrodes to obtain a display discharge. However, since the sheet resistance of the transparent electrode is as high as several tens Ω / cm ² , the electrode resistance is several tens of kΩ. The applied voltage pulse does not rise sufficiently and driving becomes difficult. Therefore, the resistance value is lowered by forming a normal metal bus electrode on the transparent electrode.

  Next, the electrode formed on the front plate is covered with a dielectric layer. This dielectric layer is made of low melting glass. Thereafter, MgO is formed by electron beam evaporation as a protective layer. The dielectric formed on the front plate has a role as a capacitor for accumulating electric charges for discharge.

  On the other hand, for the back plate, an electrode for writing display data is produced on a glass substrate using a photosensitive silver paste. On this, a partition wall is formed that secures a discharge space, defines a distance between electrodes, and prevents erroneous discharge. Next, a phosphor that emits light of each color of red, green, and blue is applied to the side and bottom of the partition wall by screen printing, and then dried and fired to form a phosphor layer.

  After sealing the back plate and the front plate with seal glass, the PDP is manufactured by exhausting, filling with a mixed gas of inert gas such as He, Ne, and Xe, and mounting a drive circuit.

  When a pulsed AC voltage is applied between adjacent transparent electrodes, a gas discharge occurs and plasma is formed. The ultraviolet rays generated here excite the phosphor to emit visible light, and display emission is obtained through the front plate. The transparent electrode that generates discharge is composed of a scan electrode and a sustain electrode. In actual panel driving, a sustain discharge pulse is applied to the transparent electrode, which is a discharge electrode, and when generating a discharge, a voltage is applied between the writing electrode on the back plate to generate a counter discharge, This discharge is maintained between the discharge electrodes by the sustain pulse.

  In the PDP having the above structure, as the area is increased and the resolution is increased, it is technically difficult to manufacture a high-aspect ratio and high-definition partition wall, and the cost is disadvantageous.

  Usually, an insulating paste made of glass is printed and dried on a front glass substrate or a back glass substrate by a screen printing method, and this printing and drying process is repeated 10 to 20 times to obtain a predetermined height, followed by firing. ing. However, in the normal screen printing method, especially when the panel size is increased, it is difficult to align the discharge electrode previously formed on the front transparent flat plate and the printing place of the insulating glass paste, and the positional accuracy is obtained. There is a difficult problem. In addition, the overlapping printing of the glass paste 10 to 20 times causes the waviness and disturbance of the side edges of the partition walls and the wall, and the accuracy of the height cannot be obtained, resulting in poor display quality. There are problems of poor workability and low yield. In particular, when the pattern width is 50 μm and the pitch is 200 μm or less, there is a problem that the bottom of the partition wall tends to bleed due to the thixotropy of the paste, making it difficult to form a sharp and residue-free partition wall.

Patent Document 1 proposes a method of forming a partition wall by a single exposure using a photosensitive paste method. However, in this method, when a pattern with a narrow line width is formed, when the partition walls are obtained by firing, disconnection, peeling, and falling of the partition walls occur, and red (R), green (G), and blue (B) When the phosphors are separately applied, there is a problem that the phosphors cannot be applied with high accuracy, color mixing occurs, luminance unevenness occurs due to the peeling of the phosphors, and the yield decreases.
Japanese Patent Laid-Open No. 8-50811

  An object of the present invention is to provide a high-definition plasma display with high yield, which prevents disconnection, peeling, and collapse of the partition during firing when forming a high-definition partition.

In order to achieve the above object, a method for producing a PDP of the present invention has the following configuration. That is, write electrode, buffer layer covering the write electrode, and wherein a plasma display panel back plate manufacturing method having a partition wall provided on the buffer layer, an inorganic powder on the substrate and a photosensitive component, and azo the organic component containing a dye, aminoketone dyes, xanthene dyes, quinoline dyes, a Ntorakinon compounds, benzophenone compounds, diphenyl cyanoacrylate compound, a UV absorber selected from a triazine based compound and p- aminobenzoic acid dyes After coating and drying the buffer layer paste containing, a photosensitive paste composed of inorganic powder mainly composed of glass fine powder and a photosensitive organic component on the light-cured buffer layer paste coating film exposed to ultraviolet light. The coating film obtained by coating and drying is exposed to a mask from above by using ultraviolet rays. Forming a barrier rib pattern moiety is removed by development, followed baked to the upper surface width (Lt) 30 to 60 m, the pitch (P) 160~220μm, forming a partition wall height (H) 100~170μm It shall be the feature.

  The high-definition partition wall having the buffer layer of the present invention does not cause separation of the partition wall during firing, so that a high-definition PDP can be manufactured with a high yield. Thereby, a high-definition plasma display can be provided. Further, it is possible to provide a plasma display having a high-definition partition wall that is not particularly thick on the lower surface of the partition wall.

  When a high-definition partition is directly formed on a glass substrate, peeling is likely to occur due to insufficient adhesion between the partition and the substrate. When the barrier ribs are peeled off, color mixture and erroneous discharge occur at the peeled portions, and the peeled barrier ribs leave the remaining pixels on the panel, resulting in a decrease in yield.

  In the present invention, it was found that by providing a high-definition partition wall on the buffer layer, the adhesion of the partition wall is increased and peeling is suppressed as compared with the case where the partition wall is formed on a glass substrate, so that the yield is improved. FIG. 1 shows an example of the structure of the PDP of the present invention.

The shape of each part of the barrier ribs of the present invention is excellent in terms of panel brightness and discharge life when the pitch is P, the line width is L, and the height is H in the following relationship.

・ When P = 160-220 μm, L = 30-60 μm, H = 100-170 μm
When the line width is smaller than the lower limit, peeling or falling during pattern formation is likely to occur, and disconnection or peeling is likely to occur after firing. If the value is larger than the above upper limit, the luminance is lowered due to a decrease in the aperture ratio, which is not preferable.

  If the height is smaller than the above lower limit, the discharge space becomes narrow, the plasma region becomes close to the phosphor, and the phosphor is sputtered, which is not preferable in terms of life. If it is larger than the above upper limit, the ultraviolet rays generated by the discharge are absorbed before reaching the phosphor, so that the luminance is lowered, which is not preferable.

  Since the partition wall for plasma display of the present invention has a tapered shape on the side surface, an adhesion area with the buffer layer can be secured, and the peeling suppression effect is further improved.

  An example of the cross-sectional shape of the partition formed by the conventional screen printing method and the partition of the present invention is shown in FIGS. 3 and 4, respectively. In the partition for plasma display of the present invention, when the lower surface width is Lb, the half width is Lh, and the upper surface width is Lt, the ratio of the upper surface width, the half value width, and the lower surface width satisfies the following expressions (1) and (2). It is preferable to be in the range.

Lt / Lh = 0.65-1 (1)
Lb / Lh = 1 to 2 (2)
(However, the case where Lt = Lh = Lb is excluded)
If Lt / Lh is greater than 1, the shape of the constriction occurs in the center of the barrier rib, and the ratio of the discharge space to the pitch of the barrier rib, that is, the aperture ratio decreases, so the luminance decreases. Further, in order to improve the luminance, the phosphor is applied not only to the bottom but also to the side wall of the partition wall, but it is difficult to apply the side surface, which is not preferable. On the other hand, if it is smaller than 0.65, the upper surface becomes too thin, the strength to withstand the atmospheric pressure applied during panel formation is insufficient, and the tip tends to be crushed.

  If Lb / Lh is smaller than 1, it is difficult to secure a close contact area with the buffer layer, and the strength of the partition walls also decreases, which may cause collapse during pattern formation, meandering, and peeling during firing. On the other hand, if it is larger than 2, the discharge space is reduced and the luminance is lowered.

  More preferably, the ranges of Lt / Lh = 0.8 to 1 and Lb / Lh = 1 to 1.5 are preferable from the viewpoint of securing the aperture ratio. However, Lt = Lh = Lb is not preferable because it is weak in strength and is likely to fall over. As the shape, a trapezoidal shape or a rectangular shape with no constriction on the lower surface of the partition wall is preferable from the viewpoint of strength.

  The inclined surface is not limited to a planar structure, and may have a curved surface shape. In particular, it is preferable to have a curved surface shape from the center of the partition wall height to the bottom surface, because even if Lb / Lh is increased, the discharge space can be increased and the luminance does not decrease. It is particularly preferable that the curved surface shape has a relationship of R ≦ Lh / 2, where R is the rounded portion of the curved surface shape of the partition wall and Lh is the half-value width, because the effect is high.

  The buffer layer used in the present invention is formed by applying a paste for a buffer layer made of an inorganic powder and an organic component on a glass substrate, then drying and baking. There are two methods of baking: a method in which a partition pattern is formed on a dried coated surface and then fired simultaneously with the partition pattern, and a method in which only a paste coating film is baked to form a buffer layer and then a partition is formed. The former firing method has an advantage that the number of steps is small. The latter method has an advantage in that when the buffer layer is formed on the electrode, the buffer layer is not cracked due to the unevenness of the electrode and the firing shrinkage stress of the partition wall, and the yield is high.

  The thickness of the buffer layer is preferably 3 to 20 μm, more preferably 8 to 18 μm after firing for the formation of a uniform buffer layer. If the thickness exceeds 20 μm, it is difficult to remove the solvent during firing, cracks are likely to occur, and the stress applied to the glass substrate is so great that the substrate is warped. In addition, when the thickness is less than 3 μm, it is difficult to maintain the uniformity of the thickness, and the buffer layer is cracked by the unevenness of the electrode portion.

The buffer layer is made of glass having a thermal expansion coefficient α ₅₀ to 400 in the range of 50 to 400 ° C. of 70 to ₈₅ × 10 ⁻⁷ / K, more preferably 72 to 80 × 10 ⁻⁷ / K. This is preferable because it matches the thermal expansion coefficient of glass and reduces the stress applied to the glass substrate during firing. If it exceeds 85 × 10 ⁻⁷ / K, a stress is applied to the surface on which the buffer layer is formed, and if it is less than 70 × 10 ⁻⁷ / K, the substrate is warped on the surface without the buffer layer. Stress is applied. For this reason, if heating and cooling of the substrate are repeated, the substrate may break. Further, when sealing with the front substrate, the two substrates may not be parallel and cannot be sealed due to the warp of the substrate.

  The glass contained in the buffer layer preferably has a glass transition point Tg of 430 to 500 ° C. and a softening point Ts of 470 to 580 ° C. When the buffer layer is formed, if the glass transition point is higher than 500 ° C. and the softening point is higher than 580 ° C., it must be fired at a high temperature, and the glass substrate is distorted during firing. A material having a glass transition point of 430 ° C. and a softening point lower than 470 ° C. is not preferable because the buffer layer is distorted when the phosphor is applied and fired in the subsequent steps, and the film thickness accuracy cannot be maintained.

  For the buffer layer, the softening point and the thermal expansion coefficient can be easily controlled by using glass fine particles containing 10 to 60% by weight of at least one of bismuth oxide, lead oxide and zinc oxide in the glass.

  If the added amount of bismuth oxide, lead oxide, or zinc oxide exceeds 60% by weight, the heat-resistant temperature of the glass becomes too low and baking on the glass substrate becomes difficult.

  The softening point and thermal expansion coefficient can also be controlled by using glass fine particles containing lithium oxide, sodium oxide, and potassium oxide, but the content is preferably 5% by weight or less, more preferably 3% by weight or less. By doing so, the stability of the paste can be improved. Further, it is effective for preventing deformation and alteration of the substrate due to a chemical reaction such as ion exchange with the substrate glass, and preventing coloring due to reaction with the metal used for the electrode.

  In particular, the use of glass containing 10 to 60% by weight of bismuth oxide has advantages such as a long pot life of the paste.

As a glass composition containing bismuth oxide, 10 to 40 parts by weight of bismuth oxide in terms of oxide, 3 to 50 parts by weight of silicon oxide, 10 to 40 parts by weight of barium oxide, 8 to 20 parts by weight, and 10 to 30 parts by weight of zinc oxide. It is preferable to contain 50% by weight or more of the composition.

  In the buffer layer of the present invention, by adding a filler as an inorganic component, the buffer layer is whitened to improve brightness during light emission, adjust the surface roughness of the buffer layer, and increase the adhesion of the partition walls. Can do.

  When the content of the filler in the buffer layer is 5 to 40% by weight of the total inorganic components, the buffer layer can be whitened and the buffer layer can be sintered at an appropriate temperature range. If it is less than 5% by weight, sufficient whiteness cannot be obtained, and if it exceeds 40% by weight, it must be fired at a high temperature, which causes problems such as distortion of the glass substrate during firing.

  As the filler of the buffer layer, titanium oxide, zinc oxide, magnesium oxide, barium titanate, or the like is preferably used. By including at least one of these, the buffer layer can be whitened. The whiteness of the buffer layer is preferably 50 or more in the Hunter color system L value.

  After the buffer layer paste coating film is baked to form the buffer layer, when the partition is formed on the buffer layer, the center line average roughness (Ra) of the surface of the buffer layer is 0.1 to 1.5 μm. If it exists, since adhesiveness with a partition increases and peeling can be prevented, it is preferable. More preferably, Ra is 0.3 to 0.9 μm.

  If Ra is less than 0.1 μm, the surface is too smooth and the adhesion between the partition walls and the buffer layer decreases when the organic binder evaporates during firing, and the partition walls are peeled off, broken, and fallen. On the other hand, when the thickness exceeds 1.5 μm, the organic matter generated during firing remains in the concavo-convex portions of the dielectric layer, and the adhesion with the partition walls is reduced, which is not preferable.

  Here, Ra is extracted from the roughness curve of the dielectric surface in the direction of the center line of a length L (L is a measurement length), the center line of the extracted portion is the X axis, and the direction of the vertical magnification is Y. When the roughness curve is expressed as Y = f (X), the value obtained by the following formula is expressed in μm.

Ra is a value measured using a stylus type surface roughness meter (Tokyo Seimitsu: Surfcom 1500A) at a vertical magnification of 2000 times and a horizontal magnification of 10 times.

  The organic components used in the buffer layer paste include organic binders, plasticizers, solvents, and additives such as dispersants and leveling agents as necessary. Specific examples of the organic binder include polyvinyl alcohol, cellulose polymer, silicon polymer, polyethylene, polyvinyl pyrrolidone, polystyrene, polyamide, high molecular weight polyether, polyvinyl butyral, methacrylic ester polymer, acrylic ester polymer, acrylic Acid ester-methacrylic acid ester copolymer, α-methylstyrene polymer, butyl methacrylate resin, and the like.

  When a barrier rib pattern is formed on the coating film by applying the buffer layer paste and dried, a binder that does not dissolve in the barrier rib developer must be selected.

  Further, the buffer layer paste contains a photosensitive component selected from at least one of a photosensitive monomer, a photosensitive oligomer, and a photosensitive polymer, and, if necessary, a photopolymerization initiator, an ultraviolet absorber, an increase agent. Additive components such as a sensitizer, a sensitization aid, and a polymerization inhibitor are also added. As a result, the buffer layer paste is imparted with photosensitivity, coated on a glass substrate, dried, exposed, and the buffer layer is photocured to prevent erosion of the buffer layer by the partition wall developer. be able to.

  It is effective to add an ultraviolet absorber to the buffer layer paste. When the barrier rib pattern is formed on the buffer layer paste coating film by the photosensitive paste method, the light used for the exposure may be reflected from the buffer layer paste coating film surface and the desired barrier rib pattern shape may not be obtained. is there. By adding a compound having a high ultraviolet absorption effect to the buffer layer paste, it is possible to obtain a high-definition pattern with no thickness on the lower surface of the partition wall by suppressing reflection from the surface of the buffer layer paste coating film. Specific examples of the ultraviolet absorber include azo dyes, amino ketone dyes, xanthene dyes, quinoline dyes, amino ketone dyes, anthraquinone compounds, benzophenone compounds, diphenyl cyanoacrylate compounds, triazine compounds, p- Aminobenzoic acid dyes can be used. Even when an organic dye is added as a light-absorbing agent, it is preferable because it does not remain in the insulating film after baking and the deterioration of the insulating film characteristics due to the light-absorbing agent can be reduced.

  When adjusting the viscosity of the buffer layer paste, it is preferable to use a binder component solvent. As the solvent, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, bromobenzene, chlorobenzene, dibromobenzene, dibromo Chlorobenzene, bromobenzoic acid, chlorobenzoic acid, and the like, and organic solvent mixtures containing one or more of these are used.

  Moreover, a plasticizer can also be included in a paste. Specific examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, polyethylene glycol, glycerin and the like.

  The method for manufacturing the partition wall of the present invention is not particularly limited, but the above-described partition wall shape (Lt / Lh = 0.65 to 1, Lb / Lh = Lb is the bottom surface width is Lb, the half width is Lh, and the top surface width is Lt. In order to obtain 1-2), it is preferable to prepare by a photosensitive paste method with few steps and capable of forming a fine pattern.

  In the photosensitive paste method, a coating film obtained by applying and drying a photosensitive paste mainly composed of an inorganic component composed mainly of glass powder and an organic component having photosensitivity is exposed to a mask, and uncured portions are removed by development, In this method, a barrier rib pattern is formed and then fired to obtain barrier ribs.

  The glass material used for the partition wall of the present invention preferably has a refractive index of 1.5 to 1.65. In general, glass used as an insulator has a refractive index of about 1.5 to 1.9. However, when the photosensitive paste method is used, the average refractive index of the organic component is larger than the average refractive index of the glass powder. If they are different, reflection / scattering at the interface between the glass powder and the photosensitive organic component increases, and a fine pattern cannot be obtained. Since the refractive index of a general organic component is 1.45 to 1.7, in order to match the refractive index of the glass powder and the organic component, the average refractive index of the glass powder is set to 1.5 to 1.65. It is preferable to do.

  When used as a partition for a plasma display or a plasma addressed liquid crystal display, the glass transition point is 430 to 500 ° C. and the thermal softening temperature is 470 to 470. It is preferable to use a glass material at 580 ° C. The amount of the glass powder used for the photosensitive paste method is preferably 65 to 85% by weight based on the sum of the glass powder and the organic component.

  If it is less than 65% by weight, the shrinkage rate at the time of firing is increased, which causes disconnection and peeling of the partition walls, which is not preferable. If it is larger than 85% by weight, the pattern forming property is deteriorated due to the small photosensitive component.

  As the composition of the partition wall material, silicon oxide is preferably blended in the glass in the range of 3 to 60% by weight, and if it is less than 3% by weight, the denseness, strength and stability of the glass layer are lowered, The coefficient of thermal expansion deviates from a desired value, and mismatching with the glass substrate is likely to occur. Moreover, by making it 60 weight% or less, there exists an advantage that a thermal softening point becomes low and baking to a glass substrate is attained.

  Boron oxide can improve electrical, mechanical, and thermal properties such as electrical insulation, strength, thermal expansion coefficient, and denseness of the insulating layer by blending in the glass in the range of 5 to 50% by weight. . If it exceeds 50% by weight, the stability of the glass decreases.

  Although it can also be obtained by using glass fine particles containing 3 to 20% by weight of at least one of lithium oxide, sodium oxide, and potassium oxide, oxides of alkali metals such as lithium, sodium, potassium, etc. 20% by weight or less, preferably 15% by weight or less, the stability of the paste can be improved.

As a glass composition containing lithium oxide, lithium oxide 2-15 parts by weight silicon oxide 15-50 parts by weight boron oxide 15-40 parts by weight barium oxide 2-15 parts by weight aluminum oxide 6-25 parts by weight in terms of oxide It is preferable to contain 50% by weight or more of the composition.

  In the above composition, sodium oxide or potassium oxide may be used instead of lithium oxide, but lithium oxide is preferable in terms of paste stability.

  By using a glass containing a total of 2 to 10% by weight of alkali metal oxides such as sodium oxide, lithium oxide and potassium oxide, the thermal softening temperature and thermal expansion coefficient can be easily controlled. Since the average refractive index can be lowered, it is easy to reduce the difference in refractive index from the organic substance. When it is less than 2%, it becomes difficult to control the heat softening temperature. If it is greater than 10%, the brightness is reduced by evaporation of the alkali metal oxide during discharge. Further, the addition amount of the alkali metal oxide is preferably less than 10% by weight, more preferably 8% by weight or less in order to improve the stability of the paste.

  In particular, among alkali metals, lithium oxide can be used to increase the stability of the paste, and when potassium oxide is used, the refractive index can be controlled even with a relatively small amount of addition. Therefore, addition of lithium oxide and potassium oxide is effective among alkali metal oxides.

  In addition, by adding aluminum oxide, barium oxide, calcium oxide, magnesium oxide, zinc oxide, zirconium oxide, etc., especially aluminum oxide, barium oxide, zinc oxide, etc., it is possible to improve the altitude and workability. However, the content is preferably 40% by weight or less, more preferably 25% by weight or less from the viewpoint of control of the thermal softening point, thermal expansion coefficient, and refractive index. As a result, it has a heat softening temperature that can be baked on the glass substrate, and can have an average refractive index of 1.5 to 1.65, making it easy to reduce the difference in refractive index from the organic component.

  Glass containing bismuth oxide is preferable from the viewpoint of heat softening temperature and water resistance improvement, but glass containing 10% by weight or more of bismuth oxide often has a refractive index of 1.6 or more. For this reason, the thermal softening temperature, thermal expansion coefficient, water resistance, and refractive index can be easily controlled by using lead oxide together with an oxide of an alkali metal such as sodium oxide, lithium oxide or potassium oxide.

  In the measurement of the refractive index of the glass material in the present invention, it is accurate to confirm the effect by measuring at the wavelength of light exposed by the photosensitive paste method. In particular, it is preferable to measure with light having a wavelength in the range of 350 to 650 nm. Furthermore, refractive index measurement with i-line (365 nm) or g-line (436 nm) is preferable.

  Since the partition wall of the present invention is excellent in increasing the contrast, it may be colored black. By adding various metal oxides, the fired partition walls can be colored. For example, a black pattern can be formed by including 1 to 10% by weight of a black metal oxide in the photosensitive paste.

  By including at least one, preferably three or more of Cr, Fe, Co, Mn, and Cu as the black metal oxide used at this time, blackening can be achieved. In particular, a black pattern can be formed by containing 0.5 wt% or more of Fe and Mn oxides.

  In addition to black, a pattern of each color can be formed by using a paste to which an inorganic pigment that develops red, blue, green, or the like is added. These colored patterns can be suitably used for a color filter of a plasma display.

  Moreover, it is preferable that the specific gravity of the partition of this invention is 2-3. In order to make it 2 or less, the glass material must contain a large amount of alkali metal oxides such as sodium oxide and potassium oxide, which is not preferable because it evaporates during discharge and deteriorates discharge characteristics. . If it becomes 3.3 or more, the display becomes heavy when the screen is enlarged, or the substrate is distorted by its own weight, which is not preferable.

  The partition wall material of the present invention may contain 10 to 50% by weight of a filler having a glass softening point of 650 to 850 ° C. Thereby, in the photosensitive paste method, the shrinkage rate at the time of baking after pattern formation becomes small, and pattern formation becomes easy. As the filler, refractory glass or ceramics having a heat softening temperature of 600 ° C. or higher can be used.

  As the high melting point glass powder, a glass powder containing 15% by weight or more of silicon oxide and aluminum oxide is preferable, and the total content thereof is 50% by weight or more in the glass powder in order to provide necessary thermal characteristics. Is effective. As an example, it is preferable to use glass powder containing the following composition.

Silicon oxide: 15-50% by weight
Boron oxide: 5 to 20% by weight
Aluminum oxide: 15-50% by weight
Barium oxide: 2 to 10% by weight
The organic component of the photosensitive paste contains a photosensitive component selected from at least one of a photosensitive monomer, a photosensitive oligomer, and a photosensitive polymer, and, if necessary, a binder, a photopolymerization initiator, and an ultraviolet absorber. Additive components such as a sensitizer, a sensitizer, a polymerization inhibitor, a plasticizer, a thickener, an organic solvent, an antioxidant, a dispersant, and an organic or inorganic precipitation inhibitor are also added.

As the photosensitive component, there are a light-insolubilized type and a light-solubilized type,
(A) containing functional monomers, oligomers or polymers having one or more unsaturated groups in the molecule (B) containing photosensitive compounds such as aromatic diazo compounds, aromatic azide compounds, and organic halogen compounds (C) What is called a diazo resin, such as a condensate of a diazo amine and formaldehyde.

In addition, as a light-soluble type,
(D) Inorganic salt of diazo compound or complex with organic acid, containing quinone diazo (E) quinone diazo combined with appropriate polymer binder, for example, naphthoquinone-1,2-diazide of phenol, novolak resin 5-sulphonic acid ester and the like.

  As the photosensitive component used in the present invention, all of the above can be used. As the photosensitive paste, the photosensitive component that can be used simply by mixing with inorganic fine particles is preferably (A).

  The photosensitive monomer is a compound containing a carbon-carbon unsaturated bond, and specific examples thereof include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, sec-butyl acrylate, sec. -Butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-pentyl acrylate, allyl acrylate, benzyl acrylate, butoxyethyl acrylate, butoxytriethylene glycol acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, 2 -Ethylhexyl acrylate, glycerol acrylate, glycidyl acrylate, heptadecafluorodecyl acrylate, 2 Hydroxyethyl acrylate, isobornyl acrylate, 2-hydroxypropyl acrylate, isodecyl acrylate, isooctyl acrylate, lauryl acrylate, 2-methoxyethyl acrylate, methoxyethylene glycol acrylate, methoxydiethylene glycol acrylate, octafluoropentyl acrylate, phenoxyethyl acrylate, stearyl Acrylate, trifluoroethyl acrylate, allylated cyclohexyl diacrylate, 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate , Dipen Erythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate, glycerol diacrylate, methoxylated cyclohexyl diacrylate, neopentyl glycol diacrylate, propylene glycol diacrylate, polypropylene glycol diacrylate, triglycerol diacrylate, tri Methylolpropane triacrylate, acrylamide, aminoethyl acrylate, phenyl acrylate, phenoxyethyl acrylate, benzyl acrylate, 1-naphthyl acrylate, 2-naphthyl acrylate, bisphenol A diacrylate, diacrylate of bisphenol A-ethylene oxide adduct, bisphenol A- Diacrylates of propylene oxide adducts, acrylates such as thiophenol acrylate, benzyl mercaptan acrylate, etc., and monomers obtained by substituting 1 to 5 of these aromatic ring hydrogen atoms with chlorine or bromine atoms, or styrene, p -Methylstyrene, o-methylstyrene, m-methylstyrene, chlorinated styrene, brominated styrene, α-methylstyrene, chlorinated α-methylstyrene, brominated α-methylstyrene, chloromethylstyrene, hydroxymethylstyrene, carboxy Methyl styrene, vinyl naphthalene, vinyl anthracene, vinyl carbazole, and those obtained by changing some or all of the acrylates in the molecule of the above compounds to methacrylate, γ-methacryloxypropyltrimethoxysilane, 1-vinyl 2-pyrrolidone, N, N, N ', N'- tetra (2-hydroxy-3-methacryloxypropyl) such as polyoxypropylene diamine. In the present invention, one or more of these can be used.

  In addition to these, the development property after exposure can be improved by adding an unsaturated acid such as an unsaturated carboxylic acid. Specific examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof.

  The content of these monomers is preferably 5 to 30% by weight with respect to the sum of the glass powder and the photosensitive component. In other ranges, the pattern formability is deteriorated and the hardness after curing is not preferable.

  Examples of the binder include polyvinyl alcohol, polyvinyl butyral, methacrylic ester polymer, acrylic ester polymer, acrylic ester-methacrylic ester copolymer, α-methylstyrene polymer, and butyl methacrylate resin.

  Moreover, the oligomer and polymer obtained by superposing | polymerizing at least 1 type among the compounds which have the above-mentioned carbon-carbon double bond can be used. In the polymerization, it can be copolymerized with other photosensitive monomers so that the content of these photoreactive monomers is 10% by weight or more, more preferably 35% by weight or more.

  As a monomer to be copolymerized, the developability after exposure can be improved by copolymerizing an unsaturated acid such as an unsaturated carboxylic acid. Specific examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof.

  The acid value (AV) of the polymer or oligomer having an acidic group such as a carboxyl group in the side chain thus obtained is preferably 50 to 180, more preferably 70 to 140. When the acid value is less than 50, the allowable development width becomes narrow. Further, if the acid value exceeds 180, the solubility of the unexposed portion in the developing solution is lowered. Therefore, if the concentration of the developing solution is increased, the exposed portion is peeled off and it is difficult to obtain a high-definition pattern.

  By adding a photoreactive group to the side chain or molecular end of the polymer or oligomer described above, it can be used as a photosensitive polymer or photosensitive oligomer having photosensitivity. Preferred photoreactive groups are those having an ethylenically unsaturated group. Examples of the ethylenically unsaturated group include a vinyl group, an allyl group, an acrylic group, and a methacryl group.

  Such a side chain can be added to an oligomer or polymer by using an ethylenically unsaturated compound having a glycidyl group or an isocyanate group relative to a mercapto group, amino group, hydroxyl group or carboxyl group in the polymer. There is a method of making an acid chloride or allyl chloride by addition reaction.

  Examples of the ethylenically unsaturated compound having a glycidyl group include glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, glycidyl ethyl acrylate, crotonyl glycidyl ether, glycidyl crotonic acid, and glycidyl ether isocrotonic acid.

  Examples of the ethylenically unsaturated compound having an isocyanate group include (meth) acryloyl isocyanate and (meth) acryloylethyl isocyanate.

  In addition, the ethylenically unsaturated compound having a glycidyl group or an isocyanate group, acrylic acid chloride, methacrylic acid chloride or allyl chloride is 0.05 to 1 molar equivalent with respect to a mercapto group, amino group, hydroxyl group or carboxyl group in the polymer. It is preferable to add.

  The amount of the polymer component consisting of the photosensitive polymer, photosensitive oligomer and binder in the photosensitive paste is excellent in terms of pattern formability and shrinkage after firing, so it is the sum of glass powder and photosensitive component. On the other hand, it is preferably 5 to 35% by weight. Outside this range, it is not preferable because pattern formation is impossible or the pattern becomes thick.

  Specific examples of the photopolymerization initiator include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamine) benzophenone, 4,4-bis (diethylamino) benzophenone, 4,4-dichlorobenzophenone, 4 -Benzoyl-4-methyldiphenyl ketone, dibenzyl ketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, p -T-butyldichloroacetophenone, 2-benzyl-2-dimethylamino-4'-morpholinobutyrophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, Dimethyldimethylketanol, benzylmethoxyethyl acetal, benzoin, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-t-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibenzosuberone, methyleneanthrone, 4-azidobenzalacetophenone, 2,6-bis (p-azidobenzylidene) cyclohexanone, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 2-phenyl-1,2-butadion-2- ( o-methoxycarbonyl) oxime, 1-phenyl-propanedione-2- (o-ethoxycarbonyl) oxime, 1,3-diphenyl-propanetrione-2- (o-ethoxycarbonyl) oxime 1-phenyl-3-ethoxy-propanetrione-2- (o-benzoyl) oxime, Michler's ketone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, naphthalenesulfonyl chloride, quinolinesulfonyl Chloride, N-phenylthioacridone, 4,4-azobisisobutyronitrile, diphenyl disulfide, benzthiazole disulfide, triphenylphosphine, camphorquinone, carbon tetrabromide, tribromophenylsulfone, benzoin peroxide and eosin, Examples include a combination of a photoreducible dye such as methylene blue and a reducing agent such as ascorbic acid or triethanolamine. In the present invention, one or more of these can be used.

  A photoinitiator is added in 0.05-20 weight% with respect to the photosensitive component, More preferably, it is 0.1-15 weight%. If the amount of the polymerization initiator is too small, the photosensitivity will be poor, and if the amount of the photopolymerization initiator is too large, the residual ratio of the exposed area may be too small.

  It is also effective to add a UV absorber. By adding a compound having a high ultraviolet absorption effect, the threshold of the photocuring reaction is increased, and curing other than the desired portion by scattered light is prevented, and a high aspect ratio, high definition, and high resolution can be obtained. Specific examples of the ultraviolet absorber include azo dyes, amino ketone dyes, xanthene dyes, quinoline dyes, amino ketone dyes, anthraquinone compounds, benzophenone compounds, diphenyl cyanoacrylate compounds, triazine compounds, p- Aminobenzoic acid dyes can be used. Even when an organic dye is added as a light-absorbing agent, it is preferable because it does not remain in the insulating film after baking and the deterioration of the insulating film characteristics due to the light-absorbing agent can be reduced.

  The addition amount of the ultraviolet light absorber is preferably 0.05 to 10% by weight with respect to the glass powder. If it is 0.05% by weight or less, the effect of adding an ultraviolet light absorber is reduced, and if it exceeds 10% by weight, the insulating film properties after firing are deteriorated, which is not preferable. More preferably, it is 0.1 to 8% by weight.

  An example of a method for adding an ultraviolet light absorber composed of an organic dye is to prepare a solution in which an organic dye is dissolved in an organic solvent in advance, and mix glass fine particles in the organic solvent in addition to kneading it at the time of preparing the paste. Thereafter, a method of drying is mentioned. By this method, so-called capsule-shaped fine particles in which the surface of each glass fine particle is coated with an organic film can be produced.

  In the present invention, when a metal and an oxide such as Pb, Fe, Cd, Mn, Co, and Mg contained in the inorganic fine particles are contained in the paste, the paste gels in a short time by reacting with the photosensitive component. It may not be possible. In order to prevent such a reaction, it is preferable to add a stabilizer to prevent gelation. As a stabilizer to be used, a triazole compound is preferably used. As the triazole compound, a benzotriazole derivative is preferably used. Of these, benzotriazole is particularly effective. As an example of the surface treatment of glass fine particles with benzotriazole used in the present invention, a predetermined amount of benzotriazole with respect to inorganic fine particles was dissolved in an organic solvent such as methyl acetate, ethyl acetate, ethyl alcohol, and methyl alcohol. Thereafter, it is immersed in the solution for 1 to 24 hours so that these fine particles can be sufficiently immersed. After soaking, the particles are preferably air-dried at 20 to 30 ° C. to evaporate the solvent to produce fine particles treated with triazole. The proportion of the stabilizer used (stabilizer / inorganic fine particles) is preferably 0.05 to 5% by weight.

  A sensitizer is added in order to improve sensitivity. Specific examples of the sensitizer include 2,4-diethylthioxanthone, isopropylthioxanthone, 2,3-bis (4-diethylaminobenzal) cyclopentanone, 2,6-bis (4-dimethylaminobenzal) cyclohexanone, 2,6-bis (4-dimethylaminobenzal) -4-methylcyclohexanone, Michler's ketone, 4,4-bis (diethylamino) -benzophenone, 4,4-bis (dimethylamino) chalcone, 4,4-bis (diethylamino) ) Chalcone, p-dimethylaminocinnamylidene indanone, p-dimethylaminobenzylidene indanone, 2- (p-dimethylaminophenylvinylene) -isonaphthothiazole, 1,3-bis (4-dimethylaminobenzal) acetone 1,3-carbonyl-bis (4-diethylamino) Benzal) acetone, 3,3-carbonyl-bis (7-diethylaminocoumarin), N-phenyl-N-ethylethanolamine, N-phenylethanolamine, N-tolyldiethanolamine, N-phenylethanolamine, isoamyl dimethylaminobenzoate And isoamyl diethylaminobenzoate, 3-phenyl-5-benzoylthiotetrazole, 1-phenyl-5-ethoxycarbonylthiotetrazole and the like. In the present invention, one or more of these can be used. Some sensitizers can also be used as photopolymerization initiators. When adding a sensitizer to the photosensitive paste of this invention, the addition amount is 0.05-10 weight% normally with respect to the photosensitive component, More preferably, it is 0.1-10 weight%. If the amount of the sensitizer is too small, the effect of improving the photosensitivity is not exhibited, and if the amount of the sensitizer is too large, the residual ratio of the exposed portion may be too small.

  In addition, a sensitizer having absorption at the exposure wavelength is used. In this case, since the refractive index becomes extremely high in the vicinity of the absorption wavelength, the organic component can be added by adding a large amount of the sensitizer. The refractive index can be improved. In this case, the sensitizer can be added in an amount of 3 to 10% by weight.

  A polymerization inhibitor is added to improve the thermal stability during storage and increase the threshold of the photocuring reaction, prevent curing other than the desired part due to scattered light, and obtain a high aspect ratio, high definition, and high resolution pattern. . Specific examples of the polymerization inhibitor include hydroquinone, monoester of hydroquinone, N-nitrosodiphenylamine, phenothiazine, pt-butylcatechol, N-phenylnaphthylamine, 2,6-di-tert-butyl-p- Examples include methylphenol, chloranil, and pyrogallol. When adding a polymerization inhibitor, the addition amount is 0.01 to 6 weight% normally in the photosensitive paste.

  Specific examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, polyethylene glycol, glycerin and the like.

  The antioxidant is added to prevent oxidation of the acrylic copolymer during storage. Specific examples of antioxidants include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-4-ethylphenol, 2,2-methylene-bis- ( 4-methyl-6-tert-butylphenol), 2,2-methylene-bis- (4-ethyl-6-tert-butylphenol), 4,4-bis- (3-methyl-6-tert-butylphenol), 1 , 1,3-Tris- (2-methyl-6-tert-butylphenol), 1,1,3-tris- (2-methyl-4-hydroxy-tert-butylphenyl) butane, bis [3,3-bis -(4-Hydroxy-3-t-butylphenyl) butyric acid] glycol ester, dilauryl thiodipropionate, triphenyl phosphite and the like.

  When adding an antioxidant, the addition amount is usually 0.001 to 1% by weight in the paste.

  An organic solvent may be added to the photosensitive paste of the present invention in order to adjust the viscosity of the solution. As an organic solvent used at this time, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, bromobenzene, Chlorobenzene, dibromobenzene, dichlorobenzene, bromobenzoic acid, chlorobenzoic acid, and the like, and organic solvent mixtures containing one or more of these are used.

  The refractive index of the organic component is the refractive index of the organic component in the paste at the time when the photosensitive component is exposed by exposure. That is, when the paste is applied and the exposure is performed after the drying process, this is the refractive index of the organic component in the paste after the drying process. For example, after apply | coating a paste on a glass substrate, there exists the method of drying at 50-100 degreeC for 1 to 30 minutes, and measuring a refractive index.

  The measurement of the refractive index in the present invention is preferably performed by an ellipsometry method or a V block method which are generally performed, and it is accurate to confirm the effect that the measurement is performed at the wavelength of light to be exposed. In particular, it is preferable to measure with light having a wavelength in the range of 350 to 650 nm. Furthermore, refractive index measurement with i-line (365 nm) or g-line (436 nm) is preferable.

  Moreover, in order to measure the refractive index after an organic component superposes | polymerizes by light irradiation, it can measure by irradiating only the organic component with the same light as the case where light is irradiated with respect to the inside of a paste.

  The buffer layer paste and the barrier rib photosensitive paste are usually prepared by mixing the above-described inorganic and organic components so as to have a predetermined composition, and then uniformly mixing and dispersing them with a three roller or kneader.

  The viscosity of the paste is appropriately adjusted depending on the addition ratio of inorganic fine particles, thickener, organic solvent, plasticizer, precipitation inhibitor, and the like, but the range is 2000 to 200,000 cps (centipoise). For example, when the application to the glass substrate is performed by a spin coating method other than the screen printing method, 200 to 5000 cps is preferable. In order to obtain a film thickness of 10 to 20 μm by applying it once by the screen printing method, 4000 to 200,000 cps is preferable.

  In order to expose a high-definition pattern on the photosensitive paste coating film for a predetermined thickness and to form a pattern with a high aspect ratio with high resolution, transmit as much actinic light for exposure as possible to the bottom of the coating film. Is essential.

  Specifically, the photosensitive paste preferably has a total light transmittance of 50% or more measured with a 50 μm-thick coating film. In addition, the measurement wavelength is accurate in confirming the effect by measuring the wavelength of the light to be exposed after applying the paste. The light transmittance is measured using a spectrophotometer (UV-3101PC) manufactured by Shimadzu Corporation.

  Next, an example in which pattern processing is performed on the buffer layer using the buffer layer paste and the photosensitive paste will be described, but the present invention is not limited thereto.

  A buffer layer paste is applied to a thickness of 5 to 30 μm on a glass substrate or a ceramic substrate. As a coating method, methods such as screen printing, bar coater, roll coater, die coater, and blade coater can be used. The coating thickness can be adjusted by selecting the number of coatings and the viscosity of the paste.

  Here, when the paste is applied onto the substrate, surface treatment of the substrate can be performed in order to improve the adhesion between the substrate and the coating film. As the surface treatment liquid, silane coupling agents such as vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, tris- (2-methoxyethoxy) vinylsilane, γ-glycidoxypropyltrimethoxysilane, γ- (methacryloxy) Propyl) trimethoxysilane, γ (2-aminoethyl) aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, or organic metals such as organic titanium, Organic aluminum, organic zirconium and the like. A silane coupling agent or an organic metal diluted with an organic solvent such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl alcohol, ethyl alcohol, propyl alcohol, or butyl alcohol to a concentration of 0.1 to 5% is used. . Next, the surface treatment liquid can be applied to the substrate uniformly with a spinner or the like, and then dried at 80 to 140 ° C. for 10 to 60 minutes to carry out the surface treatment.

  After applying the buffer layer paste, drying is performed to remove the solvent in the paste. Thereafter, there are two cases where the partition pattern is formed on the buffer layer obtained by firing the buffer layer paste coating film, and the partition pattern is formed on the coating film without firing. In the former case, the firing atmosphere and temperature vary depending on the type of paste and substrate, but firing is performed in an atmosphere of air, nitrogen, hydrogen, or the like. As the firing furnace, a batch-type firing furnace or a belt-type continuous firing furnace can be used. When it is on a glass substrate, it is fired by holding at a temperature of 540 to 610 ° C. for 10 to 60 minutes. In the latter case, when the buffer layer paste contains a light or thermopolymerizable component, it is cured by light or thermal crosslinking to prevent erosion by the developer during formation of the partition pattern by the photosensitive paste method.

  A photosensitive paste is applied over the entire surface or partially on the formed buffer layer or buffer layer paste coating film. After coating, exposure is performed using an exposure apparatus. In general, the exposure is performed by mask exposure using a photomask, as in normal photolithography. As the mask to be used, either a negative type or a positive type is selected depending on the type of the photosensitive organic component. Alternatively, a method of directly drawing with a red or blue laser beam or the like without using a photomask may be used.

  As the exposure apparatus, a stepper exposure machine, a proximity exposure machine or the like can be used. Moreover, when performing exposure of a large area, after apply | coating the photosensitive paste on a board | substrate and exposing while conveying, a large area can be exposed with the exposure machine of a small exposure area.

Examples of the active light source used in this case include visible light, near ultraviolet light, ultraviolet light, electron beam, X-ray, and laser light. Among these, ultraviolet light is preferable. Mercury lamps, ultra-high pressure mercury lamps, halogen lamps, germicidal lamps, etc. can be used. Among these, an ultrahigh pressure mercury lamp is suitable. Although exposure conditions vary depending on the coating thickness, exposure is performed for 0.1 to 30 minutes using an ultrahigh pressure mercury lamp with an output of 1 to 100 mW / cm ² .

  The pattern shape can be improved by providing an oxygen shielding film on the surface of the coated photosensitive paste. As an example of the oxygen shielding film, a film such as polyvinyl alcohol (PVA) or cellulose, or a film such as polyester can be used.

  The PVA film is formed by uniformly applying an aqueous solution having a concentration of 0.5 to 5% by weight on a substrate by a method such as a spinner and then evaporating moisture by drying at 70 to 90 ° C. for 10 to 60 minutes. . In addition, it is preferable to add a small amount of alcohol to the aqueous solution because it improves the paintability with the insulating film and facilitates evaporation. A more preferable solution concentration of PVA is 1 to 3% by weight. Within this range, the sensitivity is further improved. The following reasons are presumed that the sensitivity is improved by application of PVA. That is, when the photosensitive component undergoes a photoreaction, if there is oxygen in the air, it is considered that the sensitivity of photocuring is disturbed, but if there is a PVA film, it is considered that the sensitivity can be improved during exposure because excess oxygen can be blocked. .

  When a transparent film such as polyester, polypropylene, or polyethylene is used, there is a method in which these films are pasted on the photosensitive paste after application.

  After exposure, development is performed using the difference in solubility between the photosensitive part and the non-photosensitive part in the developer. In this case, the immersion method, the shower method, the spray method, and the brush method are used. As the developer to be used, an organic solvent in which an organic component in the photosensitive paste can be dissolved can be used. Further, water may be added to the organic solvent as long as its dissolving power is not lost. When a compound having an acidic group such as a carboxyl group is present in the photosensitive paste, development can be performed with an aqueous alkaline solution. A metal alkali aqueous solution such as sodium hydroxide, sodium carbonate, calcium hydroxide aqueous solution or the like can be used as the alkali aqueous solution. However, it is preferable to use an organic alkali aqueous solution because an alkaline component can be easily removed during firing.

  As the organic alkali, an amine compound can be used. Specific examples include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine, and diethanolamine. The concentration of the alkaline aqueous solution is usually 0.01 to 10% by weight, more preferably 0.1 to 5% by weight. If the alkali concentration is too low, the soluble portion is not removed, and if the alkali concentration is too high, the pattern portion may be peeled off and the non-soluble portion may be corroded. The development temperature during development is preferably 20 to 50 ° C. in terms of process control.

  Next, firing is performed in a firing furnace. The firing atmosphere and temperature vary depending on the type of paste and substrate, but firing is performed in an atmosphere of air, nitrogen, hydrogen, or the like. As the firing furnace, a batch-type firing furnace or a belt-type continuous firing furnace can be used.

  In the case of patterning on a glass substrate, baking is performed by holding at a temperature of 540 to 610 ° C. for 10 to 60 minutes.

  Moreover, you may introduce | transduce a 50-300 degreeC heating process for the purpose of drying and a preliminary reaction in each process of the above application | coating, exposure, image development, and baking.

  Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to this. The concentration (%) in Examples and Comparative Examples is% by weight unless otherwise specified.

Example 1
<Preparation of organic components> Solvents shown below and the following polymers were mixed to form a 40% solution and heated to 60 ° C. with stirring to dissolve all the polymers homogeneously.

Solvent: gamma butyrolactone polymer: 0.4 equivalents of glycidyl to the carboxyl group of the copolymer consisting of 40% methacrylic acid (MAA), 30% methyl methacrylate (MMA) and 30% styrene (St) A photosensitive polymer having a weight average molecular weight of 43,000 and an acid value of 95, obtained by addition reaction of methacrylate (GMA).

  Next, the solution was cooled to room temperature, and each component constituting the organic component was added to the polymer solution at the ratio shown below and dissolved. Thereafter, this solution was filtered using a 400 mesh filter to produce an organic vehicle A1.

Organic vehicle A1 composition Organic dye: Sudan IV (Azo-based organic dye, chemical formula C ₂₄ H ₂₀ N ₄ O, molecular weight 380.45) 0.2% by weight
Polymer solution: 49.3 wt%
Monomer: TPA330 (Nippon Kayaku Co., Ltd .: trimethylolpropane triacrylate / modified PO) 19.7% by weight
Initiator: Irgacure 907 (manufactured by Ciba Geigy: 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone) 3.1% by weight
Sensitizer: DETX-S (Nippon Kayaku Co., Ltd .: 2,4-diethylthioxanthone) 3.1% by weight
Sensitization aid: EPA (Nippon Kayaku Co., Ltd .: p-dimethylaminobenzoic acid ethyl ester) 1.6% by weight
Plasticizer: dibutyl phthalate (DBP) 2.7% by weight
Thickener: SiO ₂ / 2- (2-butoxyethoxy) ethyl acetate solution (concentration 15 wt%) 6.3 wt%
Solvent: 14.0% by weight of gamma butyrolactone
75 g of the following glass powder (1) was added to 60 g of the obtained organic vehicle, and kneaded uniformly with three rollers to produce a photosensitive paste for partition walls. The glass powder used was finely powdered with an attractor in advance.

Glass powder (1)
Composition _{Li 2 O 9%, SiO 2} 22%, B 2 O 3 33%, BaO 4%, Al 2 O 3 23%, ZnO 2%, 7% MgO. Non-spherical powder with an average particle size of 2.6 μm. Tg (glass transition point) 480 ° C., Ts (softening point) 520 ° C. Thermal expansion coefficient 79 × 10 ⁻⁷ / K. Refractive index 1.59 at g-line (436 nm).

  Next, a glass substrate (PD-200 manufactured by Asahi Glass Co., Ltd.) having a size of 240 × 300 mm (A4 size) was used as the glass substrate for the back plate. Two kinds of stripe electrodes having a pitch of 150 μm, a line width of 60 μm, a thickness of 6 μm after firing, a pitch of 220 μm, a line width of 80 μm, and a thickness of 6 μm after firing are formed on this glass substrate by using a photosensitive silver paste as a writing electrode. Formed.

  Next, an organic vehicle A2 having the following composition was prepared under the same conditions as A1, and 50 g of A2 and 85 g of glass powder (2) shown below were uniformly kneaded using a three roller, and a buffer layer A paste was prepared.

Organic vehicle A2 composition Organic dye: Sudan IV (azo organic dye, chemical formula C ₂₄ H ₂₀ N ₄ O, molecular weight 380.45) 0.2% by weight
Polymer solution: 52.5% by weight of the same polymer solution as A1
Monomer: TPA330 (Nippon Kayaku Co., Ltd .: trimethylolpropane triacrylate modified PO) 10.5% by weight
Initiator: Irgacure 907 (manufactured by Ciba Geigy: 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone) 4.0% by weight
Sensitizer: DETX-S (Nippon Kayaku Co., Ltd .: 2,4-diethylthioxanthone) 4.0% by weight
Sensitization aid: EPA (Nippon Kayaku Co., Ltd .: p-dimethylaminobenzoic acid ethyl ester) 2.0% by weight
Plasticizer: Dibutyl phthalate (DBP) 3.5% by weight
Thickener: SiO 2 / 2- (2-butoxyethoxy) ethyl acetate solution (concentration 15% by weight) 8.3% by weight
Solvent: 15.0% by weight gamma butyrolactone
Glass powder (2)
Composition Bi ₂ O ₃ 27%, SiO ₂ 14%, B ₂ O ₃ 18%, BaO 14%, Al ₂ O ₃ 4%, ZnO 21%, Na ₂ O 2%. Non-spherical powder with an average particle size of 3.4 μm. Tg 486 ° C, Ts 531 ° C. Coefficient of thermal expansion 75 × 10 ⁻⁷ / K. Refractive index 1.75 at g-line (436 nm).

The obtained buffer layer paste was applied by screen printing using a 325 mesh screen and dried, and after drying, a uniform film having a thickness of 20 μm was obtained. The coating thickness was adjusted by the squeegee angle and speed. The buffer layer paste coating film thus obtained was exposed to ultraviolet light with an ultrahigh pressure mercury lamp having an output of 15 mW / cm ² from the upper surface, and photocured. The exposure amount was 1000 mJ / cm ² .

Next, on the photocured film, the barrier rib photosensitive paste was applied and dried by the same method as the buffer layer paste application to form a film having a coating thickness of 200 μm. Then, it hold | maintained at 80 degreeC for 1 hour, and dried.

Subsequently, the film was exposed to ultraviolet rays with a super high pressure mercury lamp having an output of 15 mW / cm ² from the upper surface through a photomask. The exposure amount was 10,000 mJ / cm ² . The following mask was used.

  A negative chrome mask having a stripe pattern with a pitch of 220 μm and a line width of 50 μm (used for a coating film having a thickness of 200 μm).

  Next, a 0.2% by weight aqueous solution of monoethanolamine maintained at 35 ° C. was developed by showering for 150 seconds, and then washed with water using a shower spray to remove the uncured space portion. Striped partition walls were formed on the provided glass substrate.

  The substrate thus obtained was baked in air at 570 ° C. for 30 minutes to form a buffer layer and partition walls. The partition wall height, top surface width, half width, bottom surface width, and buffer layer thickness were measured by cross-sectional observation of the substrate using a scanning electron microscope, and the average value of three samples was calculated. Moreover, the presence or absence of the disconnection of the partition after baking, peeling, and the fall was evaluated. When there was no defect of disconnection, peeling, or falling, it was marked with ◯, and when there was the defect, the ratio of the number of defective partition walls to the total number of partition walls was expressed in%. The results are shown in Table 1.

  A phosphor layer was formed in a predetermined groove in the partition wall of the back plate on which the partition wall was formed by screen printing. That is, when forming red (R), alignment is performed using the photosensitive phosphor paste of R, and printing is performed. The same operation was performed for green (G) and blue (B), followed by firing (500 ° C., 30 minutes) to form three-color phosphors at predetermined positions.

  The front plate was produced by the following process. First, ITO was formed on a glass substrate by a sputtering method, a resist was applied, and a transparent electrode having a fired thickness of 0.1 μm and a line width of 200 μm was formed by exposure / development processing and etching processing. Also, a bus electrode having a thickness of 10 μm after firing was formed by photolithography using a photosensitive silver paste made of black silver powder. Electrodes with a pitch of 220 μm and a line width of 80 μm were produced.

  Furthermore, 20 μm of a transparent dielectric paste was applied on the electrode-formed front plate, and baked by holding at 430 ° C. for 20 minutes. Next, an MgO film having a thickness of 0.5 μm was formed using an electron beam vapor deposition device so as to uniformly cover the formed transparent electrode, black electrode, and dielectric layer, thereby completing the front plate.

  Next, a low melting point glass paste as a sealant is provided on the glass substrate for the front plate and the back plate, aligned to face each other in a predetermined arrangement, and processed at 450 ° C. for 30 minutes to seal the glass substrate. did. Thereafter, the plasma display panel was completed by exhausting the inside of the display region and enclosing a mixed gas of He 99% and Xe 1%. A voltage was applied to this panel for display. The brightness when the entire surface was turned on was measured using a side light machine MCPD-200 manufactured by Otsuka Electronics.

There were no defects such as color mixing of phosphors due to separation of the barrier ribs and erroneous discharge, and the display was good. The luminance was 150 cd / m ² . Example 2
A PDP was prepared and evaluated in the same manner as in Example 1 except that the glass powder for the partition walls was changed to the following (3). The results are shown in Table 1.

Glass powder (3)
Composition _{Li 2 O 7%, SiO 2} 23%, B 2 O 3 33%, BaO 4%, CaO 4%, Al 2 O 3 19%, 6% MgO, ZnO 3%, ZrO 2 1%. Non-spherical powder with an average particle size of 2.6 μm. Tg 485 ° C, Ts 525 ° C. Coefficient of thermal expansion 75 × 10 ⁻⁷ / K. Refractive index at g-line (436 nm) of 1.58.

There were no defects such as color mixing of phosphors due to separation of the barrier ribs and erroneous discharge, and the display was good. The luminance was 150 cd / m ² .

Example 3
A PDP was prepared and evaluated in the same manner as in Example 1 except that the organic vehicle for the partition wall was changed to A3 below and the exposure amount to the photosensitive paste coating film for the partition wall was 1 J / cm ² . The results are shown in Table 1.

Organic vehicle A3 composition Organic dye: Sudan IV (azo organic dye, chemical formula C ₂₄ H ₂₀ N ₄ O, molecular weight 380.45) 0.2% by weight
Polymer solution: 53.5% by weight of the same polymer solution as A1
Monomer: MGP-400: N, N, N ′, N′-tetra (2-hydroxy-3-methacryloxypropyl) polyoxypropylenediamine 20.0% by weight
Initiator: Irgacure 369 (manufactured by Ciba-Geigy: 2-benzyl-2-dimethylamino-4′-morpholinotylophenone) 7.0% by weight
Sensitizer: DETX-S (Nippon Kayaku Co., Ltd .: 2,4-diethylthioxanthone) 7.0% by weight
Plasticizer: Dibutyl phthalate (DBP) 2.3 wt%
Solvent: gamma butyrolactone 10.0% by weight
There were no defects such as color mixing of phosphors due to separation of the barrier ribs and erroneous discharge, and the display was good. The luminance was 150 cd / m ² .

Example 4
A PDP was produced and evaluated in the same manner as in Example 3 except that the glass powder of the buffer layer paste was changed to the glass powder (4) shown below. The results are shown in Table 1.

Glass powder (4)
Composition Bi ₂ O ₃ 38%, SiO ₂ 7%, B ₂ O ₃ 19%, BaO 12%, Al ₂ O ₃ 3%, ZnO 21%, Tg 476 ° C., Ts 525 ° C., coefficient of thermal expansion 75 × 10 ^{− 7} / K.

There were no defects such as color mixing of phosphors due to separation of the barrier ribs and erroneous discharge, and the display was good. The luminance was 150 cd / m ² .

Example 5
A PDP was prepared and evaluated in the same manner as in Example 4 except that the glass powder for partition walls was changed to glass powder (3). The results are shown in Table 1. There were no defects such as color mixing of phosphors due to separation of the barrier ribs and erroneous discharge, and the display was good. The luminance was 150 cd / m ² .

Reference example 1
A PDP was prepared and evaluated in the same manner as in Example 1 except that the composition of the organic vehicle for the buffer layer was changed to A4 shown below and the entire surface of the coating film of the buffer layer paste was not exposed to ultraviolet rays. The results are shown in Table 1.

Organic vehicle A4 composition polymer solution: polyvinyl butyral (non-photosensitive polymer weight average molecular weight 114000) / isobutanol solution (concentration 20% by weight) 94.6% by weight
Plasticizer: 1.6% by weight of dibutyl phthalate (DBP)
Thickener: SiO ₂ / 2- (2-butoxyethoxy) ethyl acetate solution (concentration 15% by weight) 3.8% by weight
There were no defects such as color mixing of phosphors due to separation of the barrier ribs and erroneous discharge, and the display was good. The luminance was 150 cd / m ² .

Reference example 2
A buffer layer paste having the following composition was applied, and a coating film having a thickness of 25 μm obtained by applying the buffer layer paste was baked in air at 560 ° C. for 30 minutes to form a buffer layer.

Glass powder (4) 50.0% by weight
White pigment: TiO ₂ (Ishihara Sangyo Co., Ltd.: TR-50) 5.0 wt%
Polymer solution: ethylcellulose / terpineol solution (concentration 50% by weight) 20.0% by weight
Thickener: SiO ₂ / 2- (2-butoxyethoxy) ethyl acetate solution (concentration 15% by weight) 5.0% by weight
Next, a barrier rib pattern was formed on the obtained buffer layer using a photosensitive paste for barrier ribs composed of 80 g of the following composition organic vehicle A5 and 70 g of glass powder (3). The exposure amount at the time of pattern formation was 400 mJ / cm ² .

Organic vehicle A5 composition UV absorber 1: Ubinal 3039 (manufactured by BASF: 2-ethylhexyl-2-cyano-3,3-diphenyl acrylate) 3.1% by weight
Ultraviolet absorber 2: Basic blue 7 0.02% by weight
UV absorber 3: 1,2,3-benzotriazole 3.9% by weight
Polymer solution: 46.8% by weight of the same polymer solution as in Example 1
Monomer: MGP400: N, N, N ′, N′-tetra (2-hydroxy-3-methacryloxypropyl) polyoxypropylenediamine 18.7% by weight
Initiator: Irgacure 369 (manufactured by Ciba-Geigy: 2-benzyl-2-dimethylamino-4′-morpholinobyllophenone) 7.5% by weight
Sensitizer: DETX-S (Nippon Kayaku Co., Ltd .: 2,4-diethylthioxanthone) 0.7% by weight
Polymerization inhibitor: Hydroquinone monomethyl ether 7.5% by weight
Plasticizer: 1.8% by weight of dibutyl phthalate (DBP)
Solvent: 9.98 wt% gamma butyrolactone
Others were produced and evaluated in the same manner as in Example 1. The results are shown in Table 1. There were no defects such as color mixing of phosphors due to separation of the barrier ribs and erroneous discharge, and the display was good. The luminance was 180 cd / m ² .

Reference example 3
A PDP was prepared and evaluated in the same manner as in Reference Example 2 except that the application thickness of the buffer layer paste was 15 μm. The results are shown in Table 1. There were no defects such as color mixing of phosphors due to separation of the barrier ribs and erroneous discharge, and the display was good. The luminance was 180 cd / m ² .

Comparative Example 1
A PDP was prepared and evaluated in the same manner as in Example 1 except that the partition walls were formed without the buffer layer. The results are shown in Table 1. There were many defects such as phosphor color mixing and false discharge due to the separation of the barrier ribs. The luminance was 130 cd / m ² .

It is PDP sectional drawing which shows the structure of PDP of this invention. It is PDP sectional drawing which shows the structure of the conventional AC type PDP. It is sectional drawing of the partition produced by the conventional screen printing method. It is a partition sectional drawing which shows the partition shape of this invention.

Explanation of symbols

1: Front glass substrate 2: Transparent dielectric layer 3: Protective layer 4: Transparent electrode 5: Bus electrode 6: Partition wall 7: Phosphor layer 8: Write electrode 9: Back glass substrate 10: Buffer layer

Claims (8)

Write electrode, the write electrode covering the buffer layer, and the method of manufacturing a plasma display panel backplate having a partition wall provided on the buffer layer, an inorganic powder on the substrate, and the photosensitive component and azo dyes, aminoketone dyes, xanthene dyes, quinoline dyes, a Ntorakinon compounds, benzophenone compounds, containing an organic component comprising diphenyl cyanoacrylate compounds, an ultraviolet absorbing agent selected from a triazine based compound and p- aminobenzoic acid dyes After applying and drying the buffer layer paste, the entire surface is exposed to ultraviolet light, and a light-cured buffer layer paste coating film is coated with an inorganic powder mainly composed of glass fine powder and a photosensitive paste composed of photosensitive organic components, The coating film obtained after drying is exposed to mask from above using ultraviolet rays, and the uncured part is removed. Forming a barrier rib pattern is removed by the image, then fired top width (Lt) 30 to 60 m, the pitch (P) 160~220μm, and forming a partition wall height (H) 100~170μm A method for manufacturing a plasma display panel.   The method for producing a plasma display panel according to claim 1, wherein the ultraviolet absorber contained in the buffer layer paste is an azo dye.   The photosensitive paste is an azo dye, aminoketone dye, xanthene dye, quinoline dye, aminoketone dye, anthraquinone compound, benzophenone compound, diphenylcyanoacrylate compound, triazine compound, and p-aminobenzoic acid dye. The manufacturing method of the plasma display panel of Claim 1 or 2 containing the ultraviolet absorber chosen from these. Top width of the barrier rib (Lt), the half-value width (Lh), the production of plasma display according to claim 1, the ratio of the bottom surface width (Lb) is equal to or in the range indicated below Method.
Lt / Lh = 0.65-1
Lb / Lh = 1-2
However, the case where Lt = Lh = Lb is excluded. The method for manufacturing a plasma display panel according to claim 1, wherein the buffer layer has a thickness of 3 to 20 μm. The plasma display panel according to claim 1, wherein the buffer layer is made of glass having a thermal expansion coefficient α ₅₀ to _{400 of 50} to ₄₀₀ ° C. and 70 to 85 × 10 ⁻⁷ / K. Manufacturing method. The plasma display panel according to claim 1, wherein the buffer layer is made of glass having a Tg (glass transition point) of 430 to 500 ° C. and a Ts (softening point) of 470 to 580 ° C. Manufacturing method. The method for manufacturing a plasma display according to any one of claims 1 to 7, wherein the buffer layer is made of glass containing 10 to 60% by weight of bismuth oxide.

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