JPH10291834A - Transfer film for forming dielectric layer and composition for forming dielectric layer - Google Patents

Abstract

(57) [Problem] To provide a transfer film capable of efficiently forming a derivative layer of PDP. Provided is a composition capable of completely decomposing and removing a binder resin even by firing at a low temperature, and forming a dielectric layer containing no organic substance derived therefrom. Provided is a composition capable of forming a film-forming material layer having excellent flexibility (roll workability) and excellent adhesion to a glass substrate. SOLUTION: The transfer film for forming a dielectric layer of the present invention is formed by forming a film forming material layer (20) containing glass powder and a binder resin on a support film (10). The dielectric layer forming composition of the present invention contains glass powder and an acrylic resin as a binder resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a transfer film and a composition used for forming a dielectric layer of a plasma display panel.

[0002]

2. Description of the Related Art Recently, a plasma display panel (hereinafter, also referred to as "PDP") has attracted attention as a flat fluorescent display having a high display luminance. FIG. 1 is a schematic diagram showing a cross-sectional shape of an AC type PDP. In the figure, reference numerals 1 and 2 denote glass substrates arranged opposite to each other, 3
Is a partition, and a cell is defined by the glass substrate 1, the glass substrate 2, and the partition 3. 4 is a glass substrate 1
5 is an address electrode fixed to the glass substrate 2, 5 is a fluorescent substance held in the cell, 7
Is a dielectric layer formed on the surface of the glass substrate 1 so as to cover the bus electrode 4, 8 is a dielectric layer formed on the surface of the glass substrate 2 so as to cover the address electrode 5, and 9 is a dielectric layer. A protective layer formed on the surface of the layer 7 and made of, for example, magnesium oxide. Here, the dielectric layer 7 is an essential component for generating plasma. The dielectric layer 7 is configured by laminating a first glass sintered body layer 7A and a second glass sintered body layer 7B, and has a thickness of, for example, 5 to 40 μm. Also, the dielectric layer 8
It is a useful component for reflecting light from the fluorescent substance 6 toward the glass substrate 1 (display surface side) and for securely fixing the glass substrate 2 and the partition wall 3. This dielectric layer 8
It is composed of a glass sintered body, and its film thickness is, for example, 5 to 80.
μm.

As a method for forming the dielectric layers 7 and 8, a paste composition containing glass powder, a binder resin and a solvent is prepared, and the paste composition is screen-printed on a glass substrate. A method is known in which a film-forming material layer is formed by applying the composition to a surface of a glass, drying the coating film, and then firing the film-forming material layer to remove an organic substance and sinter the glass powder. . Here, examples of the binder resin (organic substance constituting the film-forming material layer) contained in the paste composition include cellulose derivatives such as methylcellulose, ethylcellulose, and carboxymethylcellulose, polyvinyl alcohol, polyvinyl butyral, polyethylene glycol, and urethane. Resins, melamine resins and the like are used. The thickness of the film forming material layer formed on the glass substrate is set at 1.3 times the thickness of the dielectric layer to be formed in consideration of the reduction in the film thickness accompanying the removal of the organic substance in the firing step. It is necessary to set the thickness of the dielectric layer to 5 to 40 μm.
In order to achieve this, it is necessary to form a film forming material layer having a thickness of about 7 to 80 μm. On the other hand, when the paste composition is applied by a screen printing method, 1
The thickness of the coating film formed by a single coating process is 5 to 25.
It is about μm. Therefore, in order to make the film-forming material layer have a predetermined thickness, it is necessary to repeatedly apply the paste composition to the surface of the glass substrate a plurality of times (for example, 2 to 5 times).

[0004]

However, the method of forming a dielectric layer including a step of applying a paste composition by a screen printing method has the following problems (1) to (4). Further, when a conventionally known resin such as a cellulose derivative is used as the binder resin constituting the paste composition, the following problems (5) and (6) occur.

<Problems due to the screen printing method> (1) The operation of repeatedly applying the paste composition a plurality of times by the screen printing method (multiple printing) is complicated and poor in workability. In addition, it is necessary to check the dispersion state of the constituent components every time the paste-like composition is applied, and in the case of poor dispersion such as precipitation of the glass powder, the dispersion treatment must be performed again. The conventional method of forming a dielectric layer through such a complicated coating process is as follows.
It is not preferable from the viewpoint of the production efficiency of PDP, and has become a significant problem with the increase in the size of the display panel.

(2) When a film forming material layer is formed by a screen printing method, particularly when a film forming material layer is formed by multiple printing, a dielectric layer formed by firing the film forming material layer is formed. It does not have a uniform film thickness (for example, the tolerance is within ± 5%). This is because, in the screen printing method, it is difficult to uniformly apply the paste composition to the surface of the glass substrate, and the larger the application area (panel size), and the larger the number of times of application in multiple printing. The more the thickness of the dielectric layer varies, the greater the degree of variation. Then, in a panel material (a glass substrate having the dielectric layer) obtained through an application process by screen printing, in the surface thereof, the dielectric characteristics due to the film thickness variations occur, and the dielectric characteristics vary. This causes display defects (luminance unevenness) in the PDP.

(3) In the screen printing method, a very small amount of air may be entrained by the paste-like composition passing through the screen, and may remain as bubbles in the film forming material layer. When the film-forming material layer containing bubbles is fired, pinholes and cracks are generated in the formed dielectric layer. Further, at the time of forming the (n + 1) th layer coating film, n
The coating film of the first layer is easily damaged by the squeegee, which may cause cracks in the dielectric layer. In addition, the dielectric layer whose insulation property has been destroyed by pinholes or cracks cannot exhibit desired dielectric properties.

(4) In the screen printing method, the mesh shape of the screen plate may be transferred to the surface of the film forming material layer, and the dielectric layer formed by firing such a film forming material layer has a surface. Is inferior in smoothness.

<Problem Due to Use of Conventionally Known Resin> (5) The firing of the film forming material layer does not exceed a temperature at which the glass substrate starts to deform (hereinafter referred to as a “strain point”) (for example, 600 ° C.). ℃ or lower). However, in the case of baking under such low temperature conditions, the binder resin in the film forming material layer cannot be completely decomposed and removed, and the organic substance derived from the binder resin (thermal Including the carbides generated due to incomplete decomposition. The same applies to the following.), And as a result, the glass sintered body (dielectric layer) is colored black or black-brown (hereinafter, such as In some cases, the quality required for the dielectric layer cannot be ensured, such as a phenomenon called “burning blackening phenomenon”).

(6) In the case where a cellulose derivative is used as the binder resin, the cellulose derivative generates heat during sintering, and due to this, bubbles may be mixed into the formed glass sintered body. Or defects such as pinholes and cracks.

The present invention has been made based on the above circumstances. A first object of the present invention is to provide a transfer film capable of efficiently forming a PDP derivative layer. A second object of the present invention is to provide a transfer film that can be efficiently formed even with a dielectric layer having a large film thickness or a large area. A third object of the present invention is to provide a transfer film capable of forming a dielectric layer having excellent film thickness uniformity. A fourth object of the present invention is to provide a transfer film capable of forming a highly reliable dielectric layer free from defects such as pinholes and cracks. A fifth object of the present invention is to provide a transfer film capable of forming a dielectric layer having excellent surface smoothness. A sixth object of the present invention is to provide a composition capable of completely decomposing and removing a binder resin even by firing performed at a low temperature, and forming a dielectric layer containing no organic substance derived therefrom. Is to provide. A seventh object of the present invention is to provide a composition capable of forming a dielectric layer free from defects due to heat generation of a binder resin during firing. An eighth object of the present invention is to provide a composition capable of forming a film-forming material layer having excellent flexibility (roll workability). A ninth object of the present invention is to provide a composition capable of forming a film forming material layer having excellent adhesion to a glass substrate.

[0012]

The transfer film for forming a dielectric layer according to the present invention is characterized in that a film forming material layer containing glass powder and a binder resin is formed on a support film. In the transfer film of the present invention, the binder resin constituting the film forming material layer is preferably an acrylic resin. The glass powder constituting the film forming material layer is preferably a mixture of 60 to 90% by weight of lead oxide, 5 to 20% by weight of boron oxide, and 5 to 20% by weight of silicon oxide. The composition for forming a dielectric layer of the present invention is a composition containing glass powder and a binder resin, which is used for forming a dielectric layer of a plasma display panel, wherein an acrylic resin is used as the binder resin. It is characterized by being contained.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

<Transfer Film> (1) Configuration of Transfer Film: FIG. 2A is a schematic cross-sectional view showing a transfer film of the present invention wound in a roll shape, and FIG. FIG. 2 is a cross-sectional view (partial detail view of (a)) showing a layer configuration. The transfer film shown in FIG. 2 includes a support film 10 and the support film 10.
And a cover film 30 formed on the surface of the film-forming material layer 20 so as to be easily peeled off.

A support film 10 constituting a transfer film
Is preferably a resin film having heat resistance and solvent resistance and having flexibility. Since the supporting film has flexibility, a film forming material layer having a uniform thickness can be formed by a roll coater or the like, and the film forming material layer can be stored in a rolled state. it can. As the resin forming the support film, for example, polyethylene terephthalate, polyester, polyethylene, polypropylene, polystyrene,
Polyimide, polyvinyl alcohol, polyvinyl chloride,
Examples thereof include fluorine-containing resins such as polyfluoroethylene, nylon, and cellulose. The thickness of the support film is, for example, 15 to 100 μm.

The film forming material layer 20 constituting the transfer film
Is a glass sintered body (dielectric layer)
The film forming material layer 20 contains glass powder and a binder resin as essential components.
Examples of the glass powder contained in the film forming material layer 20 include zinc oxide, boron oxide, and silicon oxide (ZnO).
-B ₂ O ₃ -SiO ₂ -based mixture, lead oxide, boron oxide, silicon oxide (PbO-B ₂ O ₃ -SiO ₂ -based)
Mixture, lead oxide, boron oxide, silicon oxide, aluminum oxide _{(PbO-B 2 O 3 -SiO} 2 -Al 2 O 3 of
Mixtures of the system), lead oxide, zinc oxide, boron oxide, can be exemplified such as a mixture of silicon oxide _{(PbO-ZnO-B 2 O} 3 -SiO 2 system). Film forming material layer 20
As a binder resin contained in, a resin that can bind glass powder with an appropriate adhesive force and is decomposed and removed at a firing temperature (for example, 500 ° C. or lower) that does not melt and deform the glass substrate, It is not particularly limited, for example, acrylic resin, cellulose derivative, polyvinyl alcohol, polyvinyl butyral, polyethylene glycol, urethane resin, melamine resin, homopolymer of lactic acid, copolymer of lactic acid and copolymerizable monomer These can be used alone or in combination of two or more. Among these, an acrylic resin is preferred from the viewpoint of excellent flexibility (roll workability) and excellent adhesion to a glass substrate. The content ratio of the binder resin in the film-forming material layer 20 is preferably 5 to 40 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the glass powder. If the proportion of the binder resin is too small, the glass powder cannot be bound and held reliably. On the other hand, if the proportion is too large, the glass sintered body (the dielectric layer ) Does not have sufficient strength. In addition to the above essential components (glass powder and binder resin), the film-forming material layer 20 includes various types of solvents, dispersants, tackifiers, plasticizers, surface tension regulators, stabilizers, defoamers, and the like. May be contained as an optional component. The thickness of the film forming material layer 20 varies depending on the content ratio of the glass powder, the type and size of the panel, and the like.
μm, and preferably 10 to 100 μm. If the thickness is less than 5 μm, the thickness of the finally formed dielectric layer becomes too small, and the desired dielectric characteristics may not be secured. Usually, when the thickness is 10 to 100 μm, the thickness of the dielectric layer required for a large panel can be sufficiently ensured.

A cover film 3 constituting a transfer film
Numeral 0 is a film for protecting the surface of the film-forming material layer 20 (contact surface with the glass substrate), which is an optional component in the transfer film of the present invention. Examples of the cover film 30 include a polyethylene terephthalate film, a polyethylene film, and a polyvinyl alcohol-based film.

(2) Method for producing transfer film: The transfer film of the present invention can be produced by forming a film-forming material layer on a support film. As a method of forming the film forming material layer, a paste composition containing glass powder, a binder resin and a solvent is applied on a support film,
A method of drying the coating film to remove part or all of the solvent can be used. The solvent contained in the paste-like composition is capable of imparting a suitable viscosity (for example, 500 to 10,000 cp) to the paste-like composition, and can be easily evaporated and removed by drying. Preferably, for example, methyl isobutyl ketone, propylene glycol monomethyl ether, turpentine, ethyl cellosolve, methyl cellosolve, terpineol, butyl carbitol acetate, butyl carbitol, benzyl alcohol, methyl lactate, ethyl lactate, butyl cellosolve acetate, ethyl-3-ethoxy Propionate, butyl cellosolve and the like can be mentioned. If an example of a preferred paste composition is shown,
100 parts by weight of a mixture (glass powder) composed of 60 to 90% by weight of lead oxide, 5 to 20% by weight of boron oxide and 5 to 20% by weight of silicon oxide, and 15 parts of acrylic resin (binder resin)
A composition containing 〜25 parts by weight and 20-40 parts by weight of propylene glycol monomethyl ether (solvent) as essential components can be given.

The method for applying the paste-like composition on a supporting film is from the viewpoint of efficiently forming a coating film having a large thickness and excellent uniformity of the thickness (for example, 40 μm ± 2 μm). Preferred examples include a coating method using a roll coater, a coating method using a doctor blade, a coating method using a curtain coater, and a coating method using a wire coater. The surface of the support film to which the paste composition is applied is preferably subjected to a release treatment. Thereby, after transferring the film-forming material layer, the support film can be easily peeled from the film-forming material layer. The coating film of the paste-like composition formed on the support film,
By drying, a part or all of the solvent is removed, and a film forming material layer constituting a transfer film is obtained. Drying conditions for the coating film with the paste composition include, for example, 4
The temperature is set at about 0 to 150 ° C. for about 0.1 to 30 minutes. The residual ratio of the solvent after drying (the content ratio of the solvent in the film forming material layer) is usually 10% by weight or less, and from the viewpoint of exhibiting the adhesion to the glass substrate and the appropriate shape retention to the film forming material layer. Preferably it is 1 to 5% by weight.

(3) Transfer of the film-forming material layer (method of using the transfer film): The film-forming material layer on the support film is collectively transferred to the surface of the glass substrate to which the electrodes are fixed.
According to the transfer film of the present invention, the film forming material layer can be reliably formed on the glass substrate by such a simple operation, so that the process of forming the dielectric layer can be improved (higher efficiency). In addition to the above, the quality of the formed dielectric layer can be improved (stable dielectric characteristics can be exhibited).

An example of the transfer process using the transfer film shown in FIG. 2 is as follows. The transfer film wound in a roll shape is cut into a size corresponding to the area of the glass substrate. After the cover film (30) is peeled off from the surface of the film forming material layer (20) in the cut transfer film, the surface of the film forming material layer (20) is brought into contact with the surface (electrode fixing surface) of the glass substrate. Lay the transfer film. The heating roller is moved on the transfer film superimposed on the glass substrate to perform thermocompression bonding. The support film (10) is peeled off from the film forming material layer (20) fixed to the glass substrate by thermocompression bonding. By the operation described above, the film forming material layer (20) on the support film (10) is transferred onto the glass substrate. Here, as the transfer conditions, for example, the surface temperature of the heating roller is 60 to 120 ° C.,
The roll pressure by the heating roller is 1 to 5 kg / cm ² , and the moving speed of the heating roller is 0.2 to 10.0 m / min.
Such an operation (transfer step) can be performed by a laminator device. The glass substrate may be preheated, and the preheating temperature may be, for example, 40 to 100 ° C.

(4) Firing of the film forming material layer: The film forming material layer (20) transferred and formed on the surface of the glass substrate is fired to form a glass sintered body (dielectric layer). Here, as a firing method, a method in which the glass substrate on which the film forming material layer (20) is transferred and formed is placed in a high-temperature atmosphere can be exemplified. Thereby, the organic substances (eg, binder resin, solvent, and various additives) contained in the film forming material layer (20)
Is decomposed and removed, and the glass powder, which is an inorganic substance, is melted and sintered. Here, the firing temperature varies depending on the melting temperature of the glass substrate, the constituents in the film forming material layer, and the like, but is, for example, 300 to 800 ° C, and more preferably 400 to 600 ° C.

(5) Modification: FIG. 3 is a cross-sectional view showing a layer structure of another example of the transfer film of the present invention. FIG.
The transfer film shown in FIG. 1 includes a support film 10, a film forming material layer 21, a film forming material layer 22, and a cover film 30.
Are laminated. Here, the film-forming material layer 21 and the film-forming material layer 22 are composed of compositions having different softening points, and the film-forming material layer 2 is in contact with the glass substrate.
The softening point (T ₂₂ ) of the composition constituting the film forming material layer 21 is higher than the softening point (T ₂₁ ) of the composition constituting the film forming material layer 21. The transfer film having such a layer configuration is superimposed on the surface (electrode fixing surface) of the glass substrate so that the film-forming material layer 22 is in contact with the transfer film, and then a heating roller is moved on the transfer film to perform thermocompression bonding. By peeling and removing the support film 10 from the film forming material layer fixed to the glass substrate by thermocompression bonding, a two-layered film forming material layer (2
2,21) can be transferred and formed on a glass substrate. Then, by firing the glass substrate on which the film forming material layers (22, 21) are formed, a two-layer dielectric layer (7A, 7B) such as the “dielectric layer 7” in FIG. 1 is formed. Can be formed. Then, the firing temperature is calculated according to the formula (T ₂₁ <
T <T ₂₂ ), the film forming material layer 22 that is in contact with the glass substrate during firing
The reaction between the electrode and the electrode is suppressed to prevent generation of bubbles, and the glass sintered body layer (dielectric layer) formed by the film forming material layer 21 has excellent surface smoothness. Can be.

<Composition for forming a dielectric layer> (1) Composition of the composition: The composition for forming a dielectric layer of the present invention is characterized by containing an acrylic resin as a binder resin. Yes, solids, pastes,
The composition includes various forms of the composition such as a liquid substance. Examples of the glass powder constituting the composition of the present invention include the mixtures, soda glass, potash glass, and quartz glass exemplified as those contained in the film-forming material layer of the transfer film. The acrylic resin constituting the composition of the present invention includes a (meth) compound represented by the following general formula (I).
A homopolymer of an acrylate compound, a copolymer of two or more (meth) acrylate compounds represented by the following general formula (I), and a (meth) acrylate compound represented by the following general formula (I) and another Copolymers with copolymerizable monomers are included.

[0024]

Embedded image

[In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents a monovalent organic group. ]

Specific examples of the (meth) acrylate compound represented by the general formula (I) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, and butyl ( (Meth) acrylate, isobutyl (meth)
Acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, amyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) Acrylate, ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, Alkyl (meth) acrylates such as isostearyl (meth) acrylate; hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, Rokishibuchiru (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2
Hydroxyalkyl (meth) acrylates such as -hydroxybutyl (meth) acrylate and 3-hydroxybutyl (meth) acrylate; phenoxyethyl (meth)
Phenoxyalkyl (meth) acrylates such as acrylate and 2-hydroxy-3-phenoxypropyl (meth) acrylate; 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2
-Alkoxyalkyl (meth) acrylates such as propoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate and 2-methoxybutyl (meth) acrylate; polyethylene glycol mono (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxy Polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, nonylphenoxy polyethylene glycol (meth) acrylate, polypropylene glycol mono (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, ethoxypolypropylene glycol (meth) acrylate, nonylphenoxy Polyalkylenes such as polypropylene glycol (meth) acrylate Recol (meth) acrylate; cyclohexyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentadienyl (meth) acrylate, bornyl ( Examples thereof include cycloalkyl (meth) acrylates such as (meth) acrylate, isobornyl (meth) acrylate, and tricyclodecanyl (meth) acrylate; benzyl (meth) acrylate, and tetrahydrofurfuryl (meth) acrylate. Among these, in the above general formula (I), the group represented by R ² is preferably a group containing an alkyl group or an oxyalkylene group, and a particularly preferred (meth) acrylate compound is butyl (meth) acrylate. , Ethylhexyl (meth) acrylate, lauryl (meth) acrylate, isodecyl (meth) acrylate and 2-ethoxyethyl (meth) acrylate. The other copolymerizable monomer is not particularly limited as long as it is a compound copolymerizable with the above (meth) acrylate compound. For example, non-polymerizable monomers such as (meth) acrylic acid, vinylbenzoic acid, maleic acid, and vinylphthalic acid are used. Saturated carboxylic acids; vinylbenzyl methyl ether, vinyl glycidyl ether, styrene, α-methylstyrene,
Examples include vinyl group-containing radically polymerizable compounds such as butadiene and isoprene. In the acrylic resin constituting the composition of the present invention, the copolymer component derived from the (meth) acrylate compound represented by the general formula (I) is usually 7
It is 0% by weight or more, preferably 90% by weight or more, and more preferably 100% by weight. The molecular weight of the acrylic resin constituting the composition of the present invention is 2,000 to 30 as a weight average molecular weight in terms of polystyrene by GPC.
It is preferably 0000, more preferably 5,000 to 200,000.

The content of the acrylic resin (binder resin) in the composition of the present invention is preferably 5 to 40 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the glass powder. It is said. If the proportion of the acrylic resin is too small, the glass powder cannot be bound and held reliably.On the other hand, if the proportion is too large, the firing step requires a long time or is not formed. Glass sintered body (dielectric layer) does not have sufficient strength and film thickness.

In the composition of the present invention, in addition to the above essential components (glass powder and acrylic resin), a resin other than acrylic resin, a solvent, a dispersing agent, a tackifier, as long as the effects of the present invention are not impaired. Various substances such as a plasticizer, a surface tension regulator, a stabilizer and an antifoaming agent may be contained as optional components. Here, as the solvent contained in the composition of the present invention, for example, methyl isobutyl ketone, propylene glycol monomethyl ether, butyl cellosolve, butyl cellosolve acetate, ethyl-
3-ethoxypropionate and the like can be mentioned.

(2) Composition preparation method: The composition of the present invention is prepared by mixing the above-mentioned glass powder, acrylic resin, solvent and optional components with a kneader such as a roll kneader, a mixer, a homomixer, a ball mill, a bead mill and the like. And can be prepared by kneading. The composition of the present invention prepared as described above is a liquid or pasty composition having fluidity suitable for application or a solid composition having plasticity suitable for molding.

(3) Formation of a film-forming material layer by the composition:
When the composition of the present invention is a composition having fluidity, the composition is applied to the surface of a glass substrate by a screen printing method or the like, and a film-forming material layer is formed by drying the coating film. Can be. Here, the drying condition of the coating film is, for example, 40 to 150 ° C. for 1 to 30 minutes. The thickness of the film forming material layer is, for example, 5 to 200 μm.
m. Further, by applying the composition of the present invention having fluidity to a support film by a roll coater method, a blade coater method, or the like, and drying the coating film to form a film-forming material layer, the transfer film of the present invention is formed. Can be manufactured. The film forming material layer thus formed has excellent flexibility (roll workability) due to containing the acrylic resin and excellent adhesion to the glass substrate. When the composition of the present invention is a composition having plasticity, the composition can be molded by a molding device such as a calender roll or an extruder to obtain a sheet-like or film-like film-forming material layer. .

(4) Firing of the film-forming material layer: The film-forming material layer formed as described above is fired to decompose organic substances (acrylic resin, residual solvent, various additives). While being removed, the glass powder melts and sinters. Here, the acrylic resin contained as the binder resin is completely thermally decomposed at a temperature of about 300 to 500 ° C. Accordingly, even when firing at a relatively low temperature (a temperature at which the glass substrate is not melted or deformed),
An organic substance derived from an acrylic resin does not remain in the obtained glass sintered body layer. In addition, since the acrylic resin does not generate heat during firing, there is no defect in the obtained glass sintered body layer due to the heat generated by the binder resin.

[0032]

Hereinafter, embodiments of the present invention will be described.
The present invention is not limited by these. In the following, “parts” indicates “parts by weight”. <Example 1> (1) Preparation of paste-like composition: 70% by weight of lead oxide, 20% by weight of boron oxide, and 1% of silicon oxide as glass powder
100 parts of a PbO—B ₂ O ₃ —SiO ₂ system mixture (softening point: 460 ° C.) having a composition of 0% by weight, butyl methacrylate (50% by weight) and n-lauryl methacrylate (50% by weight) as binder resins And 20 parts of an acrylic resin (weight average molecular weight in terms of polystyrene by GPC: 90,000) obtained by copolymerizing the above, 30 parts of methyl isobutyl ketone as a solvent, and 6 parts of glycidylpropyltrimethoxysilane as an additive. The resulting mixture was kneaded to prepare a paste composition 1 having a viscosity of 3,000 cp.

(2) Production of transfer film: The paste composition 1 prepared in the above (1) was subjected to a release treatment from a polyethylene terephthalate support film (width 60).
(0 mm, length 20 m, thickness 38 μm) using a blade coater, and drying the formed coating film at 100 ° C. for 5 minutes to remove the solvent and support a film forming material layer having a thickness of 40 μm. Formed on film. Next, a cover film (thickness: 25) made of polyethylene terephthalate previously subjected to a release treatment is formed on the surface of the formed film forming material layer.
μm), and the supporting film, the film forming material layer,
A transfer film of the present invention in which a cover film was laminated was manufactured.

(3) Step of transferring film forming material layer: After peeling off the cover film from the surface of the film forming material layer of the transfer film manufactured in the above (2), a glass substrate for a 40-inch panel (strain point: 580) C), a transfer film was superimposed on the surface (fixed surface of the bus electrode) so that the surface of the film-forming material layer was in contact with the surface, and the transfer film was thermocompression-bonded with a heating roller. Here, as the pressure bonding conditions, the surface temperature of the heating roller was 100 ° C., the roll pressure was 3 kg / cm ² , and the moving speed of the heating roller was 0.5 m / min. After the completion of the thermocompression bonding, the support film was peeled off from the film forming material layer. As a result, the film-forming material layer was transferred to and adhered to the surface of the glass substrate. The thickness (average thickness and tolerance) of the transferred film forming material layer was measured and found to be in the range of 40 μm ± 1 μm.

(4) Firing step of film-forming material layer: The glass substrate on which the film-forming material layer has been transferred and formed according to the above (3) is placed in a firing furnace, and the temperature in the furnace is raised from room temperature to 10 ° C./min. The temperature was raised to 400 ° C. at a rate of temperature increase, followed by baking for 30 minutes in a temperature atmosphere of 400 ° C., and further increased to 560 ° C. at a rate of 10 ° C./min. For 60 minutes in a temperature atmosphere of 560 ° C. By performing the baking treatment, a dielectric layer made of a glass sintered body was formed on the surface of the glass substrate. When the film thickness (average film thickness and tolerance) of this dielectric layer was measured, it was in the range of 20 μm ± 0.5 μm, and the film was excellent in film thickness uniformity.

(5) Performance Evaluation of Dielectric Layer: In this way, five panel materials made of a glass substrate having a dielectric layer were prepared. When the cross section and surface of the formed dielectric layer were observed with a scanning electron microscope, film defects such as pinholes and cracks and firing blackening were observed in the dielectric layers formed on all panel materials. I couldn't.

<Examples 2 to 6> Paste-like compositions were prepared in the same manner as in Example 1 except that the type of acrylic resin as a binder resin (composition of constituent monomers) was changed in accordance with the formulation shown in Table 1. Products 2 to 6 were prepared, and a transfer film was manufactured in the same manner as in Example 1 using each of the prepared paste compositions 2 to 6, and the film-forming material layer of the transfer film was formed on a glass substrate. The dielectric layer was formed by transferring and firing the transferred film forming material layer. The viscosity of the paste composition, the thickness (average thickness and tolerance) of the film-forming material layer transferred to the surface of the glass substrate, the thickness of the dielectric layer (average thickness and tolerance), and the performance of the dielectric layer Table 1 shows the measurement results and evaluation results of the evaluation (presence or absence of a film defect and blackening phenomenon by firing).

Example 7 (1) Preparation of Paste Composition: As a glass powder, lead oxide 60% by weight, boron oxide 10% by weight, silicon oxide 3
100 parts of a PbO—B ₂ O ₃ —SiO ₂ system mixture (softening point: 560 ° C.) having a composition of 0% by weight, and polybutyl methacrylate as binder resin (weight average molecular weight in terms of polystyrene by GPC: 90,000). 25 parts, propylene glycol monomethyl ether 45 as a solvent
Parts, 8 parts of glycidylpropyltrimethoxysilane as an additive was kneaded with a disperser to give a viscosity of 2,
A 300 cp paste composition 7 was prepared.

(2) Production of transfer film: The paste composition 7 prepared in the above (1) was preliminarily released from a support film made of polyethylene terephthalate (width 60).
(0 mm, length 20 m, thickness 38 μm) using a blade coater, and drying the formed coating film at 100 ° C. for 3 minutes to remove the solvent and support a film forming material layer having a thickness of 25 μm. Formed on film. Next, a cover film (thickness: 25) made of polyethylene terephthalate previously subjected to a release treatment is formed on the surface of the formed film forming material layer.
μm), and the supporting film, the film forming material layer,
A transfer film of the present invention in which a cover film was laminated was manufactured.

(3) Step of transferring film-forming material layer: After peeling off the cover film from the surface of the film-forming material layer of the transfer film produced in the above (2), the surface of a 40-inch panel glass substrate (bus electrode) Transfer film on the fixing surface) so that the surface of the film forming material layer is in contact with the film,
This transfer film was thermocompression-bonded with a heating roller. Here, the crimping conditions were the same as in Example 1. After the completion of the thermocompression bonding, the support film was peeled off from the film forming material layer. As a result, the film-forming material layer was transferred to and adhered to the surface of the glass substrate. The thickness (average thickness and tolerance) of the transferred film forming material layer was measured and found to be in the range of 25 μm ± 0.5 μm.

(4) Firing step of film-forming material layer: The glass substrate on which the film-forming material layer has been transferred and formed by the above (3) is placed in a firing furnace, and the temperature in the furnace is changed from room temperature to 10 ° C./min. The temperature was raised to 450 ° C. at a rate of temperature increase, and the calcining treatment was performed for 30 minutes in a temperature atmosphere of 450 ° C., and further increased to 580 ° C. at a rate of 10 ° C./min. By performing the baking treatment, a dielectric layer made of a glass sintered body was formed on the surface of the glass substrate. When the film thickness (average film thickness and tolerance) of this dielectric layer was measured, it was in the range of 12 μm ± 0.2 μm, and the film was excellent in film thickness uniformity.

(5) Performance Evaluation of Dielectric Layer: In this way, five panel materials made of a glass substrate having a dielectric layer were prepared. When the cross section and surface of the formed dielectric layer were observed with a scanning electron microscope, film defects such as pinholes and cracks and firing blackening were observed in the dielectric layers formed on all panel materials. I couldn't.

Example 8 Example 1 (1) was repeated except that 25 parts of polyvinyl butyral (weight average molecular weight in terms of polystyrene by GPC: 50,000) was used as a binder resin in accordance with the formulation shown in Table 1. A paste-like composition 8 was prepared in the same manner, and a transfer film was manufactured in the same manner as in Example 1 except that the obtained paste-like composition 8 was used, and a film-forming material layer of the transfer film was used as a glass substrate. Then, the transferred film forming material layer was baked to form a dielectric layer. The viscosity of the paste composition 8, the thickness of the film forming material layer transferred to the surface of the glass substrate (average thickness and tolerance), the thickness of the dielectric layer (average thickness and tolerance), and the thickness of the dielectric layer Table 1 shows the measurement results and evaluation results of the performance evaluation (the presence or absence of the film defect and the blackening phenomenon by firing).

Comparative Example 1 The paste composition (1) prepared in Example 1 (1) was subjected to multiple printing using a screen printing method to form a glass substrate (substrate similar to that used in the example). ) To form a film-forming material layer.
Here, the dry film thickness by one application was about 9 to 10 μm, and the number of applications was four. When the film thickness of the obtained film forming material layer was measured, it was in the range of 40 μm ± 6 μm. Next, a baking treatment was performed in the same manner as in Example 1 to form a dielectric layer on the surface of the glass substrate. When the film thickness of this dielectric layer was measured, it was in the range of 20 μm ± 3 μm, and the uniformity of the film thickness was poor. In this way, five panel materials made of a glass substrate having a dielectric layer were produced. When the cross section and the surface of the formed dielectric layer were observed with a scanning electron microscope, it was found that 60%
With respect to the panel materials (for three units), film defects such as minute pinholes and cracks were observed.

[0045]

[Table 1]

<Experimental Example 1 (Evaluation of flexibility of film-forming material layer)> (1) Preparation of test piece: Paste compositions 1 to 8 prepared in Examples 1 to 8, 20 parts of ethyl cellulose as binder resin Example 1 except that a paste composition C1 for comparison prepared in the same manner as in Example 1 (1) was used, and 20 parts of polystyrene was used as a binder resin.
Each of the comparative paste compositions C2 prepared in the same manner as in (1) was coated on a support film (thickness: 38 μm) made of polyethylene terephthalate to form a coating film. The solvent was removed by drying at 5 ° C. for 5 minutes to prepare a test piece consisting of a transfer film having a 40 μm-thick film-forming material layer formed on a support film.

(2) Test and evaluation: Metal pipes having different outer diameters (outer diameter: 5 mm, 10 mm, 20 mm, 40 m
m, 60 mm, 80 mm), each of the test pieces prepared as described above was wound with the support film outside, and the support film was peeled off, and the surface of the film-forming material layer was visually observed. Observation was made to confirm the occurrence of cracks. Table 2 shows the results.

<Experimental Example 2 (Evaluation of Adhesion of Film Forming Material Layer to Glass Substrate)> (1) Preparation of Test Piece: Paste Compositions 1 to 8 and C1 to C2 were prepared in advance. A coating film was formed by applying the film on a support film (thickness: 38 μm) made of polyethylene terephthalate subjected to release treatment, and the formed coating film was dried at 100 ° C. for 10 minutes to remove the solvent. A film forming material layer was formed on the support film. Next, a cover film (thickness: 25 μm) made of polyethylene terephthalate, which has been subjected to a release treatment in advance, is adhered to the surface of the formed film forming material layer, and the support film, the film forming material layer, and the cover film are laminated. A test piece comprising the transfer film of the present invention was prepared.

(2) Test and evaluation: The test piece prepared as described above was cut into a size of 10 cm square, the cover film was peeled off, and a film was formed on the surface of a 15 cm square electrode-less glass substrate. The transfer films were overlapped so that the surfaces of the material layers were in contact with each other, and the transfer films were thermocompression-bonded using a heating roller. Here, as the pressing conditions, the surface temperature of the heating roller is 110 ° C., and the roll pressure is 2.5 k.
g / cm ² and the moving speed of the heating roller was 1 m / min. After the completion of the thermocompression bonding, the support film was peeled off from the film-forming material layer, and it was observed whether or not the film-forming material layer adhered to the peeled support film, and the adhesion to the substrate was evaluated. The test piece with good adhesion had all of the film forming material adhered to the glass substrate when the support film was peeled off,
In the test piece having poor adhesion, a part of the film forming material was adhered to the support film. Table 2 shows the results.

[0050]

[Table 2]

[0051]

According to the transfer film of the present invention, even a dielectric layer having a large thickness (for example, 5 to 40 .mu.m) can be efficiently formed by a simple method including a step of transferring a film forming material layer. Thus, the process for forming the dielectric layer can be improved, and the production efficiency of the PDP can be improved. Further, according to the transfer film of the present invention, a dielectric layer having a large film thickness can be formed while maintaining uniformity of the film thickness (within a film thickness tolerance of 5%), which is required for a large PDP. Even a dielectric layer can be formed efficiently. Further, according to the transfer film of the present invention, it is possible to form a dielectric layer excellent in uniformity of film thickness and surface smoothness and free from defects such as pinholes and cracks. Then, stable dielectric properties are exhibited by such a highly reliable dielectric layer, and as a result, display defects such as luminance unevenness do not occur in a PDP manufactured using the transfer film of the present invention. .

According to the composition of the present invention, the binder resin can be completely decomposed and removed by firing at a low temperature condition (for example, 400 to 600 ° C.) which does not exceed the strain point of the glass substrate. A dielectric layer that does not contain an organic substance derived from the above can be formed. Further, the formed dielectric layer is of high quality without defects such as pinholes, cracks and coloring caused by heat generation of the binder resin during firing. Further, according to the composition of the present invention, a film-forming material layer having excellent flexibility (roll processability) can be formed. Further, according to the composition of the present invention, a film-forming material layer having excellent adhesion to a glass substrate can be formed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a cross-sectional shape of an AC type plasma display panel.

FIG. 2A is a schematic cross-sectional view illustrating a transfer film of the present invention, and FIG. 2B is a cross-sectional view illustrating a layer configuration of the transfer film.

FIG. 3 is a cross-sectional view illustrating a layer configuration of another example of the transfer film of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Glass substrate 3 Partition wall 4 Bus electrode 5 Address electrode 6 Fluorescent substance 7 Dielectric layer 7A First glass sintered body layer 7B Second glass sintered body layer 8 Dielectric layer 9 Protective layer 10 Support film 20 Film forming material layer 21 Film forming material layer 22 Film forming material layer 30 Cover film

 ────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Atsushi Kumano 2--11-24 Tsukiji, Chuo-ku, Tokyo Inside Nippon Gosei Rubber Co., Ltd.

Claims (2)

[Claims] 1. A transfer film for forming a dielectric layer, wherein a film-forming material layer containing glass powder and a binder resin is formed on a support film. 2. A composition for forming a dielectric layer, comprising an acrylic resin as glass powder and a binder resin.