KR102439472B1 - Method for producing a release layer - Google Patents

Abstract

A composition for forming a release layer comprising a polyamic acid having both terminals derived from tetracarboxylic acid and sealed with 2-aminophenol at one or both terminals of the two terminals and an organic solvent is applied on a substrate, the highest temperature Provided is a method for producing a release layer comprising a step of firing at 400°C or higher.

Description

Method for producing a release layer

The present invention relates to a method for producing a release layer.

In recent years, in addition to the characteristics of thickness reduction and weight reduction, it is calculated|required to provide the function of being bendable to an electronic device. For this reason, it is required to use a lightweight flexible plastic substrate instead of the conventional heavy and fragile glass substrate that cannot be bent.

In particular, in a new generation display, development of an active matrix type full-color TFT display panel using a lightweight flexible plastic substrate (hereinafter referred to as a resin substrate) is required. Diversion of this new-generation display technology to various fields such as flexible displays, flexible smart phones, and mirror displays is expected.

Then, various examinations of the manufacturing method of the electronic device which used the resin film as a board|substrate are beginning, and examination of the process which can divert the existing equipment for TFT display panel manufacture in a new-generation display is advancing.

For example, in Patent Documents 1, 2 and 3, an amorphous silicon thin film layer is formed on a glass substrate, a plastic substrate is formed on the thin film layer, and then a laser is irradiated from the glass substrate side to crystallize the amorphous silicon, A method of peeling a plastic substrate from a glass substrate by hydrogen gas generated by crystallization is disclosed.

Further, in Patent Document 4, a method of attaching a layer to be peeled (described as a “transferred layer” in Patent Document 4) to a plastic film using the techniques disclosed in Patent Documents 1 to 3 to complete a liquid crystal display device is disclosed. has been

However, in the methods disclosed in Patent Documents 1 to 4, particularly in the method disclosed in Patent Document 4, it is essential to use a substrate with high light transmittance in order to transmit laser light, and hydrogen contained in the amorphous silicon to pass through the substrate. There are problems such as that it is necessary to irradiate a laser beam with a relatively large energy sufficient to emit the ray, and the laser beam irradiation may damage the layer to be peeled off.

Moreover, when a layer to be peeled has a large area, since a long time is required for laser processing, it is difficult to raise the productivity of device manufacture.

Japanese Patent Application Laid-Open No. 10-125929 Japanese Patent Application Laid-Open No. 10-125931 International Publication No. 2005/050754 Japanese Patent Application Laid-Open No. 10-125930

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing a release layer that can be peeled off without damaging a resin substrate of a flexible electronic device.

MEANS TO SOLVE THE PROBLEM As a result of repeating earnest examination in order to solve the said subject, this inventor uses the composition containing the polyamic acid in which either or both of the tetracarboxylic-acid terminal is sealed with 2-aminophenol, and an organic solvent, By setting the firing temperature at the time of forming the release layer to be higher than or equal to the predetermined maximum achieved temperature, it is possible to form a release layer having excellent adhesion to a substrate and suitable adhesion to a resin substrate used for a flexible electronic device and appropriate release property. found and completed the present invention.

That is, the present invention is

1. A composition for forming a release layer comprising a polyamic acid having both terminals derived from tetracarboxylic acid and one or both terminals of which is sealed with 2-aminophenol and an organic solvent is applied on a substrate; A method for producing a release layer comprising the step of firing at a maximum temperature of 400° C. or higher;

2. The manufacturing method of the release layer of 1, wherein the polyamic acid is a polyamic acid obtained by reacting a diamine component containing an aromatic diamine with an acid dianhydride component containing an aromatic tetracarboxylic dianhydride;

3. The method for producing the release layer of 2, wherein the aromatic diamine is an aromatic diamine containing 1 to 5 benzene nuclei;

4. A method for producing a release layer of 2 or 3, wherein the aromatic tetracarboxylic dianhydride is an aromatic tetracarboxylic dianhydride containing 1 to 5 benzene nuclei;

5. A method for manufacturing a flexible electronic device comprising a resin substrate, comprising using a release layer formed using the manufacturing method of any one of 1 to 4;

6. A flexible electronic comprising a step of forming a resin substrate by applying a composition for forming a resin substrate on a release layer formed using the manufacturing method of any one of 1 to 4, and then baking at a maximum temperature of 450° C. or higher a method of manufacturing the device;

7. The manufacturing method of the flexible electronic device of 5 or 6, wherein the resin substrate is a polyimide resin substrate

provides

By employing the method for producing a release layer of the present invention, a release layer having excellent adhesion to a base material, adequate adhesion to a resin substrate, and appropriate release property can be obtained with good reproducibility. Therefore, in the manufacturing process of a flexible electronic device by implementing the manufacturing method of this invention, the said resin substrate together with the said circuit etc., without damage to the resin substrate formed on the base|substrate, and the circuit provided on it, etc. It becomes possible to separate from the gas. Therefore, the manufacturing method of this invention can contribute to the simplification of the manufacturing process of the flexible electronic device provided with a resin substrate, its yield improvement, etc.

(Form for implementing the invention)

Hereinafter, the present invention will be described in more detail.

In the method for producing a release layer according to the present invention, a release layer is formed comprising a polyamic acid having both ends derived from tetracarboxylic acid, and either or both ends of which are sealed with 2-aminophenol, and an organic solvent. It is characterized in that it comprises a step of coating the composition on a substrate and firing at a maximum temperature of 400°C or higher.

Here, the release layer in the present invention is a layer provided directly on a glass substrate for a predetermined purpose, and a typical example thereof is a flexible electronic device composed of a substrate and a resin such as polyimide in a manufacturing process of a flexible electronic device. Peeling provided between the resin substrate and the resin substrate to fix the resin substrate in a predetermined process, and provided so that the resin substrate can be easily peeled from the substrate after an electronic circuit or the like is formed on the resin substrate layers can be taken.

The polyamic acid used by this invention can be obtained by making either one or both of the polymer chain terminal of the polyamic acid which has both terminals derived from tetracarboxylic acid react with the amino group of 2-aminophenol, and sealing. That is, as for the polyamic acid obtained here, either or both of the molecular chain terminals are sealed by the phenyl group containing a hydroxyl group.

When the polymer terminal has a hydroxyl group, a difference in the skeleton and the flexible substrate used for the upper layer may occur, so that the function of the resulting film as a release layer can be improved.

In this invention, although the hydroxyl group originating in 2-aminophenol should just exist in either one of the polymer chain terminals of a polyamic acid, it is preferable that the hydroxyl group originating in 2-aminophenol exists in both ends of a polymer chain.

Moreover, as a diamine component and acid dianhydride component used when manufacturing a polyamic acid, from a viewpoint of improving the function as a peeling layer of the film|membrane obtained, the diamine component containing aromatic diamine, and acid dianhydride containing aromatic tetracarboxylic dianhydride The polyamic acid obtained by making a water component react is preferable.

Although it does not specifically limit as long as it has two amino groups in a molecule|numerator and has an aromatic ring as aromatic diamine, The aromatic diamine containing 1-5 benzene nuclei is preferable.

Specific examples thereof include 1,4-diaminobenzene (p-phenylenediamine), 1,3-diaminobenzene (m-phenylenediamine), 1,2-diaminobenzene (o-phenylenediamine), 2, 4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, 4,6-dimethyl-m-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, 2,6- Dimethyl-p-phenylenediamine, 2,4,6-trimethyl-1,3-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, m-xylylenediamine, p- Xylylenediamine, 5-trifluoromethylbenzene-1,3-diamine, 5-trifluoromethylbenzene-1,2-diamine, 3,5-bis(trifluoromethyl)benzene-1,2- diamine having one benzene nucleus such as diamine; 1,2-naphthalenediamine, 1,3-naphthalenediamine, 1,4-naphthalenediamine, 1,5-naphthalenediamine, 1,6-naphthalenediamine, 1,7-naphthalenediamine, 1,8-naphthalenediamine, 2 ,3-naphthalenediamine, 2,6-naphthalenediamine, 4,4'-biphenyldiamine, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'- Dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'- Diaminodiphenylmethane, 4,4'-diaminobenzanilide, 3,3'-dichlorobenzidine, 3,3'-dimethylbenzidine, 2,2'-dimethylbenzidine, 3,3'-diaminodiphenylmethane , 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 2,2-bis(3-aminophenyl)propane, 2,2-bis(4-aminophenyl)propane, 2 ,2-bis(3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-bis(4-aminophenyl)-1,1,1,3,3, 3-hexafluoropropane, 3,3'-diaminodiphenylsulfoxide, 3,4'-diaminodiphenylsulfoxide, 4,4'-diaminodiphenylsulfoxide, 3,3'-bis( Trifluoromethyl) biphenyl-4,4'-diamine, 3,3',5,5'-tetrafluorobiphenyl-4,4'-diamine, 4,4'-diaminooctafluorobiphenyl, 2 diamines having two benzene nuclei, such as -(3-aminophenyl)-5-aminobenzimidazole and 2-(4-aminophenyl)-5-aminobenzoxazole; 1,5-diaminoanthracene, 2,6-diaminoanthracene, 9,10-diaminoanthracene, 1,8-diaminophenanthrene, 2,7-diaminophenanthrene, 3,6-diaminophenanthrene , 9,10-diaminophenanthrene, 1,3-bis(3-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(3-aminophenyl)benzene, 1 ,4-bis(4-aminophenyl)benzene, 1,3-bis(3-aminophenylsulfide)benzene, 1,3-bis(4-aminophenylsulfide)benzene, 1,4-bis(4-aminophenyl) Sulfide)benzene, 1,3-bis(3-aminophenylsulfone)benzene, 1,3-bis(4-aminophenylsulfone)benzene, 1,4-bis(4-aminophenylsulfone)benzene, 1,3- Bis[2-(4-aminophenyl)isopropyl]benzene, 1,4-bis[2-(3-aminophenyl)isopropyl]benzene, 1,4-bis[2-(4-aminophenyl)isopropyl ] Benzene, 4,4''-diamino-p-terphenyl, 4,4''-diamino-m-terphenyl, etc. Although three diamines are mentioned, It is not limited to these. These may be used individually or in combination of 2 or more types. Further, in the present invention, it is preferable to use the aromatic diamine that does not contain an ether bond or an ester bond.

Among them, an aromatic diamine composed only of an aromatic ring and a heteroaromatic ring having no substituent such as a methyl group on the aromatic ring and the heterocyclic ring condensed thereon from the viewpoint of improving the function as a release layer of the obtained film is preferable. Specifically, p-phenylenediamine, m-phenylenediamine, 2-(3-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-5-aminobenzoxazole, 4, 4''-diamino-p-terphenyl and the like are preferred.

The aromatic tetracarboxylic dianhydride is not particularly limited as long as it has two dicarboxylic acid anhydride moieties and an aromatic ring in the molecule, but it is an aromatic tetracarboxylic dianhydride containing 1 to 5 benzene nuclei. This is preferable.

Specific examples thereof include pyromellitic dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, naphthalene-1,2,3,4-tetracarboxylic dianhydride, and naphthalene-1,2,5. ,6-tetracarboxylic dianhydride, naphthalene-1,2,6,7-tetracarboxylic dianhydride, naphthalene-1,2,7,8-tetracarboxylic dianhydride, naphthalene-2,3, 5,6-tetracarboxylic dianhydride, naphthalene-2,3,6,7-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, biphenyl-2, 2',3,3'-tetracarboxylic dianhydride, biphenyl-2,3,3',4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic Acid dianhydride, anthracene-1,2,3,4-tetracarboxylic dianhydride, anthracene-1,2,5,6-tetracarboxylic dianhydride, anthracene-1,2,6,7-tetra Carboxylic acid dianhydride, anthracene-1,2,7,8-tetracarboxylic dianhydride, anthracene-2,3,6,7-tetracarboxylic dianhydride, phenanthrene-1,2,3,4 -tetracarboxylic dianhydride, phenanthrene-1,2,5,6-tetracarboxylic dianhydride, phenanthrene-1,2,6,7-tetracarboxylic dianhydride, phenanthrene-1,2 ,7,8-tetracarboxylic dianhydride, phenanthrene-1,2,9,10-tetracarboxylic dianhydride, phenanthrene-2,3,5,6-tetracarboxylic dianhydride, phenanthrene -2,3,6,7-tetracarboxylic dianhydride, phenanthrene-2,3,9,10-tetracarboxylic dianhydride, phenanthrene-3,4,5,6-tetracarboxylic dianhydride Although water, phenanthrene-3,4,9,10-tetracarboxylic dianhydride, etc. are mentioned, It is not limited to these. These may be used individually or in combination of 2 or more types.

Especially, from a viewpoint of improving the function as a peeling layer of the film|membrane obtained, the aromatic carboxylic dianhydride of 1 or 2 benzene nucleus is preferable. Specifically, the aromatic tetracarboxylic dianhydride represented by any one of formulas (C1) to (C12) is preferable, and the aromatic represented by any one of formulas (C1) to (C7) and (C9) to (C11) is preferable. Tetracarboxylic dianhydride is more preferable.

In addition, from the viewpoint of improving the flexibility, heat resistance, and the like of the release layer obtained, the diamine component used in the present invention may contain diamines other than aromatic diamine, and the tetracarboxylic dianhydride component used in the present invention is aromatic tetracarboxylic acid. You may also contain tetracarboxylic dianhydride other than an acid dianhydride.

In the present invention, the amount of the aromatic diamine in the diamine component is preferably 70 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, still more preferably 95 mol% or more, and most preferably is 100 mol%. The amount of the aromatic tetracarboxylic dianhydride in the tetracarboxylic acid component is preferably 70 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, still more preferably 95 mol% or more. , most preferably 100 mol%. By employing such a usage-amount, a film having excellent adhesion to a substrate, suitable adhesion to a resin substrate, and moderate peelability can be obtained with good reproducibility.

After the diamine component and the tetracarboxylic dianhydride component described above are reacted, the obtained polyamic acid is reacted with 2-aminophenol so that the end of the polymer chain contained in the composition for forming a release layer of the present invention is 2-amino A polyamic acid sealed with phenol can be obtained.

Since the charging ratio of the diamine component and the tetracarboxylic dianhydride component is appropriately determined in consideration of the target molecular weight and molecular weight distribution, the type of diamine and the type of tetracarboxylic dianhydride, etc., it cannot be defined uniformly. In order to set it as the both terminal of molecular chain derived from an acid, it is preferable to slightly increase the number of moles of a tetracarboxylic dianhydride component with respect to the number of moles of a diamine component. As a specific molar ratio, 1.02-3.0 mol of a tetracarboxylic dianhydride component is preferable with respect to 1 mol of a diamine component, 1.07-2.5 mol is more preferable, 1.1-2.0 mol is further more preferable.

The organic solvent used in the synthesis of the polyamic acid and the sealing of the molecular chain terminal of the synthesized polyamic acid is not particularly limited as long as it does not adversely affect the reaction, and specific examples thereof include m-cresol, 2-pyrrolidone, N-methyl- 2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, 3-methoxy-N,N -Dimethylpropylamide, 3-ethoxy-N,N-dimethylpropylamide, 3-propoxy-N,N-dimethylpropylamide, 3-isopropoxy-N,N-dimethylpropylamide, 3-butoxy- N,N-dimethylpropylamide, 3-sec-butoxy-N,N-dimethylpropylamide, 3-tert-butoxy-N,N-dimethylpropylamide, γ-butyrolactone, and the like can be mentioned. In addition, you may use an organic solvent individually by 1 type or in combination of 2 or more type.

In particular, since the organic solvent used for the reaction dissolves diamine, tetracarboxylic dianhydride and polyamic acid well, amides represented by formula (S1), amides represented by (S2), and amides represented by formula (S3) At least one selected from the amides used is preferable.

In the formula, R ¹ and R ² each independently represent an alkyl group having 1 to 10 carbon atoms. R ³ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Although h represents a natural number, Preferably it is 1-3, More preferably, it is 1 or 2.

Examples of the alkyl group having 1 to 10 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n -heptyl group, n-octyl group, n-nonyl group, n-decyl group, etc. are mentioned. Among these, a C1-C3 alkyl group is preferable, and a C1-C2 alkyl group is more preferable.

The reaction temperature at the time of synthesizing the polyamic acid may be appropriately set within the range from the melting point to the boiling point of the solvent to be used, and is usually about 0 to 100 ° C. From the viewpoint of maintaining the The reaction time cannot be defined uniformly because it depends on the reaction temperature or the reactivity of the raw material, but is usually about 1 to 100 hours.

The reaction temperature at the time of sealing the molecular chain terminal of the polyamic acid may be appropriately set within the range from the melting point to the boiling point of the solvent used, as in the synthesis of polyamic acid, and is usually about 0 to 100 ° C. From a viewpoint of sealing the molecular chain terminal of a polyamic acid reliably, Preferably it is about 0-70 degreeC, More preferably, it is about 0-60 degreeC, More preferably, it can be set as about 0-50 degreeC. The reaction time cannot be defined uniformly because it depends on the reaction temperature or the reactivity of the raw material, but is usually about 1 to 100 hours.

The weight average molecular weight of the polyamic acid obtained in this way, in which one or both ends of the molecular chain are sealed with 2-aminophenol, is usually about 5,000 to 500,000, but from the viewpoint of improving the function as a release layer of the resulting film, it is preferably It is about 6,000-200,000, More preferably, it is about 7,000-150,000. In the present invention, the weight average molecular weight is a polystyrene conversion value measured by gel permeation chromatography (GPC).

In the present invention, usually, the reaction solution after terminal sealing can be used as it is, or a solution obtained by diluting or concentrating can be used as the composition for forming a release layer of the present invention. In addition, you may filter the said reaction solution as needed. In addition to being able to reduce the mixing of impurities which may cause deterioration of adhesiveness, peelability, etc. of the peeling layer obtained by filtration, the composition for peeling layer formation can be obtained efficiently. Moreover, after isolating a polyamic acid from the said reaction solution, it is good also as a composition for peeling layer formation by dissolving in a solvent again. As a solvent in this case, the organic solvent etc. used for the reaction mentioned above are mentioned.

The solvent used for dilution is not specifically limited, The thing similar to the specific example of the reaction solvent of the said reaction is mentioned as the specific example. The solvent used for dilution may be used individually by 1 type or in combination of 2 or more type. Among them, it dissolves polyamic acid well, so N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-ethyl -2-pyrrolidone and γ-butyrolactone are preferable, and N-methyl-2-pyrrolidone is more preferable.

Moreover, even if it is a solvent which does not melt|dissolve a polyamic acid independently, if it is a range in which a polyamic acid does not precipitate, it can mix with the composition for peeling layer formation of this invention. In particular, ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy -2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, A solvent having a low surface tension, such as dipropylene glycol, 2-(2-ethoxypropoxy)propanol, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, etc. can be mixed appropriately. . Thereby, it is known that the uniformity of a coating film improves at the time of application|coating to a board|substrate, and it can use suitably also with the composition for peeling layer formation of this invention.

The concentration of the polyamic acid in the composition for forming a release layer of the present invention is appropriately set in consideration of the thickness of the release layer to be produced, the viscosity of the composition, and the like, but is usually about 1 to 30% by mass, preferably 1 to 20% by mass % is about By setting it as such a density|concentration, the peeling layer with a thickness of about 0.05-5 micrometers can be obtained with good reproducibility. The concentration of polyamic acid is determined by adjusting the amount of diamine and tetracarboxylic dianhydride, which are raw materials of polyamic acid, diluting or concentrating the filtrate after filtering the reaction solution, or dissolving the isolated polyamic acid in a solvent. It can be adjusted by adjusting the amount, etc.

The viscosity of the composition for forming a release layer of the present invention is appropriately set in consideration of the thickness of the release layer to be produced. It is about 10-10,000 mPa*s, Preferably it is about 20-5,000 mPa*s.

Here, the viscosity can be measured using a commercially available viscometer for measuring the viscosity of a liquid, for example, referring to the procedure described in JIS K7117-2, and measuring the composition at a temperature of 25°C. Preferably, a conical plate type (cone plate type) rotational viscometer is used as the viscometer, preferably 1°34'×R24 is used as a standard cone rotor as a homogeneous viscometer, and the composition is measured at a temperature of 25°C. can do. As such a rotational viscometer, TVE-25L manufactured by Toki Sangyo Co., Ltd. is mentioned, for example.

Moreover, the composition for peeling layer formation of this invention may contain the crosslinking agent etc. in order to improve film|membrane strength other than a polyamic acid and an organic solvent, for example.

In a firing method including a step of applying the above-described composition for forming a release layer on a substrate and then firing at a maximum temperature of 400° C. or higher, thermal imidization of polyamic acid results in excellent adhesion to the substrate and proper adhesion to the resin substrate. A release layer made of a polyimide film having adhesiveness and moderate peelability can be obtained.

In the present invention, the maximum temperature at the time of firing is not particularly limited as long as it is in the range of 400° C. or higher and less than or equal to the heat resistance temperature of the polyimide. In consideration of improving the Moreover, although the upper limit is about 550 degreeC normally, about 510 degreeC is preferable. By setting the heating temperature in the above range, it is also possible to sufficiently advance the imidization reaction while preventing the resulting film from becoming brittle.

Since the heating time varies with the heating temperature, it cannot be defined uniformly, but is usually 1 minute to 5 hours. Moreover, what is necessary is just to be the range of 50 to 100% of imidation ratio.

In addition, the temperature at the time of the said baking may include the process of baking at the temperature below that, as long as the maximum temperature becomes the said range.

As a preferable example of the heating mode in this invention, after heating at 50-150 degreeC, the method of raising a heating temperature in stages as it is and finally heating at 400 degreeC or more is mentioned. In particular, as a more preferable example of a heating mode, the method of heating at 50-100 degreeC, heating at more than 100 degreeC - less than 400 degreeC, and heating at 400 degreeC or more is mentioned. Moreover, as another more preferable example of a heating mode, after heating at 50-150 degreeC, it heats at more than 150 degreeC - 350 degreeC, then, it heats at more than 350 degreeC - 450 degreeC, and finally, it heats at more than 450 degreeC - 510 degreeC. method can be found.

In addition, as a preferable example of the heating mode when the firing time is considered, the method is heated at 50 to 150°C for 1 minute to 2 hours, then the heating temperature is raised stepwise as it is, and finally heated to 400°C or higher for 30 minutes to 4 hours. can be heard In particular, as a more preferable example of the heating mode, a method of heating at 50 to 100°C for 1 minute to 2 hours, heating at more than 100°C to less than 400°C for 5 minutes to 2 hours, and heating at 400°C or higher for 30 minutes to 4 hours can be heard Moreover, as another more preferable example of a heating mode, after heating at 50-150 degreeC for 1 minute to 2 hours, it is over 150 degreeC - 350 degreeC for 5 minutes to 2 hours, then it is over 350 degreeC - 450 degreeC for 30 minutes - 4 hours; Finally, the method of heating more than 450 degreeC - 510 degreeC for 30 minutes - 4 hours is mentioned.

In addition, when forming the peeling layer of this invention on a base|substrate, the peeling layer may be formed in one part surface of a base|substrate, and may be formed in the whole surface. As an aspect of forming the release layer on a part of the surface of the substrate, the release layer is formed only in a predetermined range of the surface of the substrate, and the release layer is formed on the entire surface of the substrate in a pattern shape such as a dot pattern, a line and space pattern, etc. There is this. In addition, in this invention, the base material means that the composition for peeling layer formation of this invention is apply|coated on the surface, and it is used for manufacture of a flexible electronic device etc.

Examples of the substrate (substrate) include glass, metal (silicon wafer and the like), slate, and the like. In particular, since the release layer of the present invention has sufficient adhesion thereto, glass is preferable. In addition, the base|substrate surface may be comprised from a single material, and may be comprised from two or more materials. As an aspect in which the surface of the substrate is composed of two or more materials, a certain range of the surface of the substrate is composed of a certain material, and the other surface is composed of other materials, and a dot pattern, a line and space pattern, etc. There are aspects such as a pattern in which a certain material is present among other materials in the shape of a pattern.

The method of applying the composition for forming a release layer of the present invention to the substrate is not particularly limited, but for example, a cast coating method, a spin coating method, a blade coating method, a dip coating method, a roll coating method, a bar coating method, and a die The coating method, the inkjet method, the printing method (iron plate, intaglio, flat plate, screen printing, etc.) etc. are mentioned.

As an apparatus used for heating, a hot plate, an oven, etc. are mentioned, for example. The heating atmosphere may be air or inert gas, and may be under normal pressure or under reduced pressure.

The thickness of the release layer is usually about 0.01 to 50 µm, and preferably about 0.05 to 20 µm from the viewpoint of productivity. In addition, a desired thickness is implement|achieved by adjusting the thickness of the coating film before a heating.

The release layer described above has excellent adhesion to the substrate, particularly glass, and moderate adhesion to the resin substrate and moderate peelability. Therefore, in the manufacturing process of a flexible electronic device, the peeling layer of this invention is suitable for peeling the said resin substrate from a base|substrate together with the circuit etc. formed on the resin substrate without damaging the resin substrate of the said device. Can be used.

Hereinafter, an example of the manufacturing method of the flexible electronic device using the peeling layer of this invention is demonstrated.

Using the composition for forming a release layer of the present invention, a release layer is formed on the glass substrate by the method described above. On this peeling layer, the resin substrate fixed to the glass substrate is formed through the peeling layer of this invention by apply|coating the solution for resin substrate formation for forming a resin substrate, and baking this coating film.

The firing temperature of the coating film is appropriately set depending on the type of resin, etc., but in the present invention, the maximum temperature at the time of this firing is preferably 450°C or higher, more preferably 480°C or higher, and 490°C or higher. It is further more preferable to set it as 500 degreeC or more. By making the highest temperature at the time of baking at the time of resin substrate preparation into this range, the adhesiveness of the peeling layer which is a base material, and a base|substrate, and moderate adhesiveness and peelability of a peeling layer and a resin substrate can be improved more.

Also in this case, as long as the maximum temperature is within the above range, the step of firing at a temperature lower than that may be included.

As a preferable example of the heating mode at the time of resin substrate preparation, after heating at 50-150 degreeC, the method of raising the heating temperature stepwise as it is and finally heating to 450 degreeC or more is mentioned. In particular, as a more preferable example of a heating mode, the method of heating at 50-100 degreeC, heating at more than 100 degreeC - less than 400 degreeC, and heating at 450 degreeC or more is mentioned. Moreover, as another more preferable example of a heating mode, after heating at 50-100 degreeC, it heats at more than 100 degreeC - 200 degreeC, then at more than 200 degreeC - less than 300 degreeC, heating at 300 degreeC - less than 400 degreeC, and 400 degreeC The method of heating at less than -450 degreeC and finally heating at 450-510 degreeC is mentioned.

In addition, as a preferable example of the heating mode when the firing time is taken into consideration, after heating at 50 to 150°C for 1 minute to 2 hours, the heating temperature is raised stepwise as it is, and finally heating at 450°C or higher for 30 minutes to 4 hours. can be heard In particular, as a more preferable example of the heating mode, a method of heating at 50 to 100°C for 1 minute to 2 hours, heating at more than 100°C to less than 400°C for 5 minutes to 2 hours, and heating at 450°C or higher for 30 minutes to 4 hours can be heard Further, as another more preferable example of the heating mode, after heating at 50 to 100°C for 1 minute to 2 hours, then at 100°C to 200°C for 5 minutes to 2 hours, then at more than 200°C to less than 300°C for 30 minutes to 4 time, a method of heating at 300°C to less than 400°C for 30 minutes to 4 hours, at 400°C to less than 450°C for 30 minutes to 4 hours, and finally at 450 to 510°C for 30 minutes to 4 hours.

The resin substrate covers all of the release layer to form a substrate with a large area compared to the area of the release layer. As a resin substrate, the resin substrate which consists of a polyimide typical as a resin substrate of a flexible electronic device is mentioned, As a resin solution for forming it, a polyimide solution and a polyamic-acid solution are mentioned. What is necessary is just to follow a conventional method for the formation method of the said resin substrate.

Next, a desired circuit is formed on the resin substrate fixed to the base through the release layer of the present invention, and then, for example, the resin substrate is cut along the release layer, and the resin substrate together with the circuit is removed from the release layer. It peels, and isolate|separates a resin substrate and a base|substrate. At this time, you may cut off a part of base|substrate together with a peeling layer.

Further, in Japanese Patent Laid-Open No. 2013-147599, it is reported that the laser lift-off method (LLO method), which has been used in the manufacture of high-brightness LEDs and three-dimensional semiconductor packages, etc., is applied to the manufacture of flexible displays. The LLO method is characterized in that light of a specific wavelength, for example, light of a wavelength of 308 nm, is irradiated from the side opposite to the surface on which the circuit or the like is formed from the side of the glass substrate. The irradiated light beam passes through the glass gas, and only the polymer (polyimide) near the glass gas absorbs the light beam and evaporates (sublimes). As a result, it becomes possible to selectively peel a resin substrate from a glass substrate without affecting the circuit etc. provided on the resin substrate which determine the performance of a display.

Since the release layer of the present invention has the characteristic of sufficiently absorbing light of a specific wavelength (eg, 308 nm) to which the LLO method can be applied, it can be used as a sacrificial layer for the LLO method. Therefore, a desired circuit is formed on a resin substrate fixed to a glass substrate through a release layer formed by using the composition in the present invention, and then LLO method is performed to irradiate a 308 nm light beam, and only this release layer is removed. It absorbs light and evaporates (sublimates). Thereby, the said peeling layer becomes a sacrifice (it acts as a sacrificial layer), and it becomes possible to selectively peel a resin substrate from a glass substrate.

Example

Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

[1] Abbreviations of compounds

NMP: N-methylpyrrolidone

BCS: Butyl Cellosolve

p-PDA: p-phenylenediamine

2AP: 2-aminophenol

BPDA: 3,3-4,4-biphenyltetracarboxylic dianhydride

PMDA: pyromellitic dianhydride

[2] Measurement of weight average molecular weight and molecular weight distribution

The weight average molecular weight (hereinafter abbreviated as Mw) and molecular weight distribution of the polymer were measured using a GPC apparatus (Shodex (registered trademark) columns KF803L and KF805L) manufactured by Nippon Bunko Co., Ltd., and dimethylformamide as the elution solvent at a flow rate of 1 ml/min, It measured on condition of the column temperature of 50 degreeC. In addition, Mw was made into polystyrene conversion value.

[3] Synthesis of polymers

By the following method, the polyamic acid was synthesize|combined.

In addition, a composition for forming a resin substrate or a composition for forming a release layer was prepared by diluting the reaction liquid as described later without isolating the polymer from the obtained polymer-containing reaction liquid.

<Synthesis Example S1 Synthesis of polyamic acid (S1)>

3.176 g (0.02937 mol) of p-PDA was dissolved in 88.2 g of NMP, and 8.624 g (0.02931 mol) of BPDA was added, followed by reaction at 23° C. under a nitrogen atmosphere for 24 hours. The obtained polymer had a Mw of 107,300 and a molecular weight distribution of 4.6.

<Synthesis Example L1 Synthesis of polyamic acid (L1)>

1.507 g (0.0139 mol) of p-PDA was dissolved in 43.2 g of NMP, and 3.166 g (0.01452 mol) of PMDA was added thereto, followed by reaction at 23° C. under a nitrogen atmosphere for 2 hours. Then, 0.127 g (0.0012 mol) of 2AP was further added, and it was made to react at 23 degreeC in nitrogen atmosphere for 24 hours. The obtained polymer had a Mw of 48,500 and a molecular weight distribution of 2.05.

<Synthesis Example L2 Synthesis of polyamic acid (L2)>

1.119 g (0.01103 mol) of p-PDA was dissolved in 35.2 g of NMP, and 3.006 g (0.01378 mol) of PMDA was added, followed by reaction at 23° C. under a nitrogen atmosphere for 2 hours. Then, 0.602 g (0.00551 mol) of 2AP was further added, and it was made to react at 23 degreeC in nitrogen atmosphere for 24 hours. Mw of the obtained polymer was 11,700, and molecular weight distribution was 1.76.

<Synthesis Example L3 Synthesis of polyamic acid (L3)>

0.681 g (0.00629 mol) of p-PDA was dissolved in 35.2 g of NMP, and 2.746 g (0.01259 mol) of PMDA was added, followed by reaction at 23° C. under a nitrogen atmosphere for 2 hours. Then, 1.373 g (0.012588 mol) of 2AP was further added, and it was made to react at 23 degreeC in nitrogen atmosphere for 24 hours. The obtained polymer had Mw of 8,000 and a molecular weight distribution of 1.57.

<Synthesis of Comparative Synthesis Example HL1 Polyamic Acid (HL1)>

1.29 g (0.00107 mol) of p-PDA was dissolved in 43.2 g of NMP, and 3.509 g (0.00119 mol) of BPDA was added thereto, followed by reaction at 23° C. under a nitrogen atmosphere for 24 hours. The obtained polymer had Mw of 34,000 and a molecular weight distribution of 2.03.

<Synthesis of Comparative Synthesis Example HL2 Polyamic Acid (HL2)>

After dissolving 1.325 g (0.00123 mol) of p-PDA in 36 g of NMP and adding 2.674 g (0.00123 mol) of PMDA, it was reacted at 23° C. under a nitrogen atmosphere for 2 hours. Unfortunately, since it was gelled, it could not be used.

[4] Preparation of a composition for forming a resin substrate

The reaction solution obtained in Synthesis Example S1 was used as a composition for forming a resin substrate as it was.

[5] Preparation of a composition for forming a release layer

[Example 1-1]

BCS and NMP were added to the reaction solution obtained in Synthesis Example L1, and the mixture was diluted so that the polymer concentration was 5 wt% and BCS was 20 mass% to obtain a composition for forming a release layer.

[Examples 1-2 to 1-3]

A composition for forming a release layer was obtained in the same manner as in Example 1-1 except that the reaction solution obtained in Synthesis Examples L2 to L3 was used instead of the reaction solution obtained in Synthesis Example L1.

[Comparative Example 1-1]

A composition for forming a release layer was obtained in the same manner as in Example 1-1 except that the reaction solution obtained in Comparative Synthesis Example HL1 was used instead of the reaction solution obtained in Synthesis Example L1.

[6] Preparation of release layer and resin substrate

[Example 2-1]

Using a spin coater (condition: rotation speed of 3,000 rpm for about 30 seconds), the composition L1 for forming a release layer obtained in Example 1-1 was applied onto a 100 mm×100 mm glass substrate (the same hereinafter) as a glass substrate.

Then, the obtained coating film was heated at 100° C. for 2 minutes using a hot plate, and then heated at 300° C. for 30 minutes using an oven, and the heating temperature was raised to 400° C. (10° C./min), 400 It was heated at °C for 30 minutes, further heated to 500 °C (10 °C/min), and heated at 500 °C for 10 minutes to form a release layer with a thickness of about 0.1 µm on the glass substrate to obtain a glass substrate with a release layer. . In addition, during the temperature increase, the film-attached substrate was heated in the oven without taking it out of the oven.

The composition S2 for resin substrate formation was apply|coated on the peeling layer (resin thin film) on the glass substrate obtained above using the bar coater (gap: 250 micrometers). Then, the obtained coating film was heated at 80° C. for 30 minutes using a hot plate, and then, using an oven, in a nitrogen atmosphere, and then heated at 140° C. for 30 minutes, and the heating temperature was raised to 210° C. (2° C.) /min, hereinafter the same), the heating temperature is increased to 300°C for 30 minutes at 210°C, the heating temperature is raised at 300°C for 30 minutes, the heating temperature is raised to 400°C, and the heating temperature is increased at 400°C for 30 minutes to 500°C. It heated up and heated at 500 degreeC for 60 minutes, the about 20-micrometer-thick polyimide resin substrate was formed on the peeling layer, and the resin substrate and the glass substrate with a peeling layer were obtained. During the temperature increase, the film-attached substrate was heated in the oven without taking it out of the oven.

[Examples 2-2-2-3]

In the same manner as in Example 2-1, except that the compositions L2 and L3 for forming a release layer obtained in Examples 1-2 to 1-3, respectively, were used instead of the composition L1 for forming a release layer obtained in Example 1-1. , a release layer and a polyimide resin substrate were formed, and a glass substrate with a release layer and a glass substrate with a resin substrate and a release layer were obtained.

[Comparative Example 2-1]

The release layer and the polyimide resin were used in the same manner as in Example 2-1 except that the composition HL1 for forming a release layer obtained in Comparative Example 1-1 was used instead of the composition L1 for forming a release layer obtained in Example 1-1. The board|substrate was formed, and the glass substrate with a peeling layer and the resin substrate and the glass substrate with a peeling layer were obtained.

[7] Evaluation of peelability

About the glass substrate with a peeling layer obtained in said Examples 2-1 to 2-3 and Comparative Example 2-1, the peelability of a peeling layer and a glass substrate was confirmed by the following method. In addition, the following test was done with the same glass substrate.

<Evaluation of cross-cut test peelability of resin thin film>

The peeling layer on the glass substrate with a peeling layer obtained in Examples 2-1 to 2-3 and Comparative Example 2-1 was cross-cut (vertical and horizontal intervals of 1 mm, hereinafter the same), and 100 square cuts were performed. That is, by this crosscut, 100 square pieces of 1 mm square were formed.

And the adhesive tape was stuck to this 100 square cut-out part, the tape was peeled, and peelability was evaluated based on the following criteria (5B-0B, B,A, AA). A result is shown in Table 1.

<Judgment Criteria>

5B: 0% peeling (no peeling)

4B: less than 5% peeling

3B: peeling less than 5-15%

2B: peeling less than 15-35%

1B: peeling less than 35-65%

0B: 65% to less than 80% peeling

B: 80% to less than 95% peeling

A: 95% to less than 100% peeling

AA: 100% peeling (all peeling)

<Evaluation of the peelability of the resin substrate>

The resin substrate of the glass substrate with a resin substrate and a peeling layer obtained in Examples 2-1 to 2-3 and Comparative Example 2-1 was cut into the strip shape of 25 mm width using the cutter. And the cellophane tape was stuck to the front-end|tip of the cut resin substrate, and this was made into the test piece. This test piece was subjected to a peeling test using a push-pull tester made by Atonic Co., Ltd. so that the peeling angle was set to 90°, and peelability was evaluated based on the following criteria. A result is shown in Table 1.

<Judgment Criteria>

5B: 0% peeling (no peeling)

4B: less than 5% peeling

3B: peeling less than 5-15%

2B: peeling less than 15-35%

1B: peeling less than 35-65%

0B: 65% to less than 80% peeling

B: 80% to less than 95% peeling

A: 95% to less than 100% peeling

AA: 100% peeling (all peeling)

release layer resin substrate Removability of the resin substrate and the release layer Peelability of a release layer and a glass substrate Example 2-1 L1 S1 AA 5B Example 2-2 L2 S1 AA 5B Example 2-3 L3 S1 AA 5B Comparative Example 2-1 HL1 S1 5B 5B

From the result of Table 1, although the peeling layer of Examples 2-1 to 2-3 could peel only a resin substrate without a peeling layer peeling from a glass substrate, it was confirmed that it was not able to peel in Comparative Example 2-1.

Claims (7)

A composition for forming a release layer comprising a polyamic acid having both terminals derived from tetracarboxylic acid and sealed with 2-aminophenol at one or both terminals of the two terminals and an organic solvent is applied on a substrate, the highest temperature A method for producing a release layer comprising a step of firing at 400° C. or higher, the method comprising:
The polyamic acid is a polyamic acid obtained by reacting a diamine component containing an aromatic diamine and an acid dianhydride component containing an aromatic tetracarboxylic acid dianhydride,
The tetracarboxylic dianhydride component contains at least one aromatic tetracarboxylic dianhydride selected from the group consisting of the following formulas (C1) to (C12), and the amount used is all tetracarboxylic dianhydride A method for producing a release layer, characterized in that 70 mol% or more in water.

The method of claim 1,
The method for producing a release layer, characterized in that the aromatic diamine is an aromatic diamine containing 1 to 5 benzene nuclei. 3. The method of claim 1 or 2,
The method for producing a release layer, wherein the aromatic tetracarboxylic dianhydride is an aromatic tetracarboxylic dianhydride containing 1 to 5 benzene nuclei. The manufacturing method of the flexible electronic device provided with the resin substrate characterized by using the peeling layer formed using the manufacturing method of Claim 1 characterized by the above-mentioned. A method for manufacturing a flexible electronic device comprising a step of forming a resin substrate by applying a composition for forming a resin substrate on a release layer formed using the manufacturing method according to claim 1, and then calcining at a maximum temperature of 450° C. or higher . 6. The method of claim 4 or 5,
The method for manufacturing a flexible electronic device, characterized in that the resin substrate is a polyimide resin substrate. delete