JP2019143144A - Composition for forming releasing layer - Google Patents

Abstract

To provide a composition for forming a releasing layer that maintains good adhesion to a glass substrate and prevents separation at the interface with the glass substrate, and enables easy separation of a layer from the releasing layer, the layer being formed on top of the releasing layer.SOLUTION: A composition for forming a releasing layer contains a polyamic acid containing 50% by mole or more of a monomer unit of formula (1) and having a weight average molecular weight of 10,000 or more, and an organic solvent. In formula (1), Xrepresents a tetravalent organic group; and Yrepresents a divalent group represented by formula (P).SELECTED DRAWING: None

Description

  The present invention relates to a composition for forming a release layer provided directly on a glass substrate.

In recent years, electronic devices have been required to have the functions of bending, thinning and lightening. For this reason, it is required to use a lightweight flexible plastic substrate in place of the conventional glass substrate that is fragile and cannot be bent. In the new generation display, development of an active full-color TFT display panel using a lightweight flexible plastic substrate is required.
Therefore, various methods for manufacturing electronic devices using a resin film as a substrate are being studied, and in the new generation display, manufacturing studies are being carried out in a process that can divert existing TFT equipment.

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 surface side to accompany crystallization of amorphous silicon. A method of peeling a plastic substrate from a glass substrate with generated hydrogen gas is disclosed.
Patent Document 4 discloses a method for attaching a layer to be peeled (described as “transfer target layer” in Patent Document 4) to a plastic film by using the techniques disclosed in Patent Documents 1 to 3 to complete a liquid crystal display device. Is disclosed.

  However, in the methods disclosed in Patent Documents 1 to 4, particularly the method disclosed in Patent Document 4, it is essential to use a highly light-transmitting substrate, and the hydrogen contained in amorphous silicon is allowed to pass through the substrate. In order to give energy sufficient to emit, there is a problem that irradiation with a relatively large laser beam is required and the layer to be peeled is damaged. In addition, since it takes a long time for laser treatment and it is difficult to peel off a layer to be peeled having a large area, there is a problem that it is difficult to increase the productivity of device fabrication.

Japanese Patent Laid-Open No. 10-125929. Japanese Patent Application Laid-Open No. 10-125931. WO2005 / 050754 pamphlet. Japanese Patent Laid-Open No. 10-125930.

Therefore, an object of the present invention is to solve the above problems.
Specifically, the objective of this invention is providing the composition for forming the peeling layer for making it peel without damaging the board | substrate applied to a flexible electronic device.

  Further, in addition to the above object or other than the above object, the object of the present invention is to maintain adhesion with a glass substrate on which a release layer is provided and does not cause peeling at the interface with the glass substrate. An object of the present invention is to provide a composition for forming a release layer, which can easily peel a layer or a group of layers formed thereon from the release layer.

  The present inventor has now found the following invention. That is, the present inventor forms a release layer using a composition containing a polyamic acid having a monomer unit having a specific structure of 50 mol% or more and a weight average molecular weight of a certain value or more, and an organic solvent. It has unexpectedly been found that the layer has suitable properties that can be peeled off without damaging the substrate applied to the flexible electronic device or the like. This layer is a layer or layer formed above the release layer on the side opposite to the glass substrate, while maintaining adhesion to the glass substrate on which the release layer is provided and hardly causing peeling at the interface with the glass substrate. About a group, it was able to peel easily from a peeling layer. The present invention is based on such knowledge.

［式中、Ｘ^１は、４価の有機基を表し、Ｙ^１は、下記の式（Ｐ）で表される２価の基を表す：

（式中、Ｒは、Ｆ、Ｃｌ、炭素数１〜３のアルキル基、又はフェニル基を表し、ｍは、０〜４の整数を表し、かつ、ｒは１〜４の整数を表す）］。 <1> A composition for forming a release layer, comprising a polyamic acid containing 50 mol% or more of a monomer unit represented by the following formula (1) and having a weight average molecular weight of 10,000 or more and an organic solvent.

[Wherein, X ¹ represents a tetravalent organic group, and Y ¹ represents a divalent group represented by the following formula (P):

(In the formula, R represents F, Cl, an alkyl group having 1 to 3 carbon atoms, or a phenyl group, m represents an integer of 0 to 4, and r represents an integer of 1 to 4)] .

（式中、
Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５及びＲ^６は、同一であっても異なっていてもよく、Ｆ、Ｃｌ、炭素数１〜３のアルキル基、又はフェニル基を表し、
ｍ１、ｍ２、ｍ３、ｍ４、ｍ５及びｍ６は、同一であっても異なっていてもよく、０〜４の整数を表す）。 <2> In the above item <1>, the Y ¹ may be a divalent group represented by any of the following formulas (P1) to (P3).

(Where
R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ may be the same or different and represent F, Cl, an alkyl group having 1 to 3 carbon atoms, or a phenyl group,
m1, m2, m3, m4, m5 and m6 may be the same or different and represent an integer of 0 to 4).

<3> The <2> Y ¹ may include at least a divalent group represented by the formula (P1).

［式中、
Ｘ^１は、前記＜１＞で定義されたとおりであり、Ｙ^２は、下記の式（Ｐ４）で表される基を表す：

（式中、
Ｒ^７、及びＲ^８は、同一であっても異なっていてもよく、Ｆ、Ｃｌ、炭素数１〜３のアルキル基、又はフェニル基を表し、
Ｒ’は、水素原子、炭素数１〜３のアルキル基、又はフェニル基を表し、 ｌは０〜４の整数を表し、かつ
ｍは、前記＜１＞で定義されたとおりである）］。 <4> In any one of the above items <1> to <3>, the polyamic acid may further include a monomer unit represented by the following formula (2).

[Where:
X ¹ is as defined in <1> above, and Y ² represents a group represented by the following formula (P4):

(Where
R ⁷ and R ⁸ may be the same or different and each represents F, Cl, an alkyl group having 1 to 3 carbon atoms, or a phenyl group;
R ′ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a phenyl group, l represents an integer of 0 to 4, and m is as defined in the above <1>).

<5> In any one of the above items <1> to <4>, X ¹ may be a tetravalent aromatic group.

  <6> In the above item <5>, the tetravalent aromatic group may have at least one selected from a benzene skeleton, a naphthalene skeleton, and a biphenyl skeleton.

（式中、Ｒ^ａ及びＲ^ｂは同一であっても異なっていてもよく、炭素数１〜４のアルキル基を表し、ｈは自然数を表す）。 <7> In any one of the above items <1> to <6>, the organic solvent may be a solvent represented by the following formula (A) or (B).

(In the formula, R ^a and R ^b may be the same or different and each represents an alkyl group having 1 to 4 carbon atoms, and h represents a natural number).

  <8> In any one of the above items <1> to <7>, the content of the monomer unit represented by the formula (1) in the polyamic acid may be 60 mol% or more.

  <9> In any one of the above items <1> to <8>, the composition for forming a release layer according to the present invention may be for forming a release layer provided directly on a glass substrate.

  <10> A release layer formed between a flexible substrate applied to a flexible electronic device and a base substrate, using the release layer forming composition according to any one of <1> to <9>. A release layer to be produced.

<11> A substrate structure applied to a flexible electronic device,
A base substrate;
A release layer that covers the base substrate in one or more regions, and is formed of the release layer forming composition according to any one of <1> to <9>;
Including the base substrate and a flexible substrate covering the release layer;
A substrate structure, wherein an adhesion force between the flexible substrate and the release layer is larger than an adhesion force between the release layer and the base substrate.

  <12> In the above item <11>, the base substrate may include glass.

  <13> A method for producing a release layer, comprising using the release layer forming composition according to any one of <1> to <9>. In one preferable aspect, the method for producing the release layer includes a step of applying the release layer forming resin composition to a substrate and heating the substrate.

<14> A method for producing a substrate structure applied to a flexible electronic device,
Preparing a base substrate,
Producing a release layer covering the base substrate in one or more regions using the release layer forming composition according to any one of <1> to <9>;
Forming a flexible substrate on the base substrate and the release layer;
The manufacturing method characterized by the adhesive force of the said flexible substrate and the said peeling layer being larger than the adhesive force of the said peeling layer and the said base base | substrate.

The present invention can solve the above problems.
Specifically, according to the present invention, it is possible to provide a composition for forming a release layer for peeling without damaging a substrate applied to a flexible electronic device.
Further, according to the present invention, in addition to the above effects or in addition to the above effects, the adhesion with the glass substrate on which the release layer is provided is maintained, and peeling at the interface with the glass substrate does not occur. It is providing the composition for forming this peeling layer which can peel the layer or layer group formed easily from a peeling layer.

  Hereinafter, the present invention will be described in detail.

Release Layer Forming Composition As described above, the release layer forming composition of the present invention is a polyamic acid containing 50 mol% or more of the monomer unit represented by the formula (1), and its weight average molecular weight is 10 , 1,000 or more polyamic acid and an organic solvent.

Further, as described above, in the formula (1), X ¹ represents a tetravalent organic group, and Y ¹ represents a divalent group represented by the following formula (P).

In Formula (P), R represents F, Cl, an alkyl group having 1 to 3 carbon atoms, or a phenyl group, and preferably represents F or Cl. Similarly, in said Formula (P), m represents the integer of 0-4, Preferably it represents 0-2, More preferably, it represents 0-1, Most preferably, it represents 0. Moreover, in said Formula (P), r represents the integer of 1-3.
The alkyl group having 1 to 3 carbon atoms includes methyl, ethyl, n-propyl, and i-propyl. Preferably, the alkyl group having 1 to 3 carbon atoms is methyl, and more preferably, Methyl.

  The weight average molecular weight of the polyamic acid having the monomer unit represented by the formula (1) used in the present invention needs to be 10,000 or more, preferably 15,000 or more, more preferably 20,000 or more, more More preferably, it is 30,000 or more. On the other hand, the upper limit value of the weight average molecular weight of the polyamic acid used in the present invention is usually 2,000,000 or less, but it is possible to suppress the viscosity of the resin composition from becoming excessively high or to have a highly flexible resin thin film. In view of obtaining a good reproducibility, etc., it is preferably 1,000,000 or less, more preferably 200,000 or less.

  In the polyamic acid used in the present invention, the monomer unit represented by the formula (1) is 50 mol% or more, preferably 60 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, Preferably it contains 90 mol% or more. By using a polyamic acid having such a monomer unit content, a resin thin film having characteristics suitable for a release film can be obtained with good reproducibility.

  According to a preferred embodiment of the present invention, the polyamic acid contained in the composition for forming a release layer of the present invention is a polymer composed only of the monomer unit represented by the formula (1), that is, the monomer represented by the formula (1). It is a polymer containing 100 mol% of units. At this time, the monomer unit in such a polyamic acid may be only one specific type or two or more types as long as it is represented by the formula (1). In the latter case, the number of monomer units of the formula (1) contained in the polyamic acid is preferably 2 to 4, more preferably 2 to 3.

  In the present invention, the group represented by the formula (P) preferably includes a divalent group represented by any one of the formulas (P1) to (P3), more preferably the formula (P1) or (P3 ), And more preferably a divalent group represented by the formula (P3).

In the above formula (P1), formula (P2) and formula (P3), R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ may be the same or different, and F, Cl represents an alkyl group having 1 to 3 carbon atoms or a phenyl group, and preferably represents F or Cl.
Similarly, in these formulas, m1, m2, m3, m4, m5 and m6 may be the same or different and each represents an integer of 0 to 4, preferably 0 to 2, more preferably 0. Represents -1, particularly preferably 0.

  The polyamic acid used in the present invention may contain other monomer units in addition to the monomer unit represented by the formula (1). The content of such other monomer units needs to be less than 50 mol%, preferably less than 40 mol%, more preferably less than 30 mol%, and less than 20 mol%. Is more preferable, and it is further more preferable that it is less than 10 mol%.

  Examples of such other monomer units include monomer units of the formula (2).

In the formula (2), X ¹ represents a tetravalent organic group, and Y ² represents a group represented by the above-described formula (P4).

In the formula (P4), R ⁷ and R ⁸ may be the same or different and represent F, Cl, an alkyl group having 1 to 3 carbon atoms, or a phenyl group. R ⁷ preferably represents F or Cl. R ⁸ preferably represents F or Cl.
R ′ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a phenyl group, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom.
Further, l and m may be the same or different and each represents an integer of 0 to 4, preferably 0 to 2, more preferably 0 to 1, and particularly preferably 0.

  Examples of such other monomer units include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2-methyl-1,4-phenylenediamine, 5 other than the monomer unit of the above formula (2). -Methyl-1,3-phenylenediamine, 4-methyl-1,3-phenylenediamine, 2- (trifluoromethyl) -1,4-phenylenediamine, 2- (trifluoromethyl) -1,3-phenylenediamine And 4- (trifluoromethyl) -1,3-phenylenediamine, benzidine, 2,2′-dimethylbenzidine, 3,3′-dimethylbenzidine, 2,3′-dimethylbenzidine, 2,2′-bis (tri Fluoromethyl) benzidine, 3,3′-bis (trifluoromethyl) benzidine, 2,3′-bis (trifluorome L) benzidine, 4,4′-diphenyl ether, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-diaminobenzanilide, 5-amino-2- (3-aminophenyl) -1H-benzo Diamines such as imidazole and 9,9-bis (4-aminophenyl) fluorene, pyromellitic anhydride (PMDA), 2,3,6,7-naphthalenetetracarboxylic dianhydride, 4,4′-oxydiphthalic acid Examples thereof include structures derived from anhydrides and acid dianhydrides such as 3,3 ′, 4,4′-benzophenonetetracarboxylic anhydride.

In Formula (1) and Formula (2), as described above, X ¹ is a tetravalent organic group, preferably a tetravalent aromatic group.

Tetravalent aromatic group X ¹ can be taken, when creating a polyamic acid used in the present invention, it is possible to create by using an aromatic tetracarboxylic dianhydride as follows.
That is, pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,3,3 ', 4'-biphenyltetracarboxylic dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 1, 2,5,6-naphthalenetetracarboxylic dianhydride, 4,4′-oxydiphthalic anhydride, 3,3 ′, 4,4′-dimethyldiphenylsilanetetracarboxylic dianhydride, 3,3 ′, 4 , 4'-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride , 4,4'-hexaf Oroisopropylidene diphthalic anhydride, paraphenylene diphthalic dianhydride, 2,2-bis-((3,4-dicarboxyphenyl) -hexafluoropropane dianhydride, 9,9-bis (3 4-dicarboxyphenyl) fluorene dianhydride, 9,9'-bis [4- (3,4-dicarboxyphenoxy) phenyl] fluorene dianhydride, 3,3 ', 4,4'-biphenyl ether tetracarboxylic Acid dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 4,4'-sulfonyldiphthalic dianhydride, Paraterphenyl-3,4,3 ′, 4′-tetracarboxylic dianhydride, metaterphenyl-3,3 ′, 4,4′-tetracarboxylic dianhydride, 3,3 ′, 4,4 ′ -Diphenyl ether Ditetracarboxylic dianhydride, 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyldisiloxane dianhydride, 1- (2,3-dicarboxyphenyl) -3- (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyldisiloxane dianhydride, 3,3 ', 4,4'-hydroquinone dibenzoate tetracarboxylic dianhydride, 2 2,2′-bis (4-hydroxyphenyl) propanedibenzoate-3,3 ′, 4,4′-tetracarboxylic acid and the like.

（式中、Ｒ_３は、芳香環を少なくとも１つ有する２価の有機基であり、好ましくは、フェニル、ビフェニル、ナフタレン骨格を有する基である）。 Preferably, the aromatic tetracarboxylic dianhydride desired here is selected from the following group of compounds.

(Wherein R ₃ is a divalent organic group having at least one aromatic ring, and preferably a group having a phenyl, biphenyl, or naphthalene skeleton).

Therefore, according to a preferred embodiment of the present invention, the tetravalent aromatic group that X ¹ can take has any of a benzene skeleton, a naphthalene skeleton, a biphenyl skeleton, and a terphenyl skeleton, and more preferably benzene Those having any of a skeleton, a naphthalene skeleton, and a biphenyl skeleton, and more preferably those having any of a benzene skeleton and a biphenyl skeleton.

  According to a preferred embodiment of the present invention, the polyamic acid used in the present invention is a 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA) (formula (4)) as an acid dianhydride. P-phenylenediamine (pPDA) (formula (5)) and 4,4 ″ -diamino-p-terphenyl (DATP) (formula (6)) as diamine, or pyromellitic acid as acid dianhydride It can be obtained by reacting dianhydride (PMDA) (formula (7)) and pPDA (formula (5)) as a diamine.

  In the above reaction, it consists of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA), p-phenylenediamine (pPDA) and 4,4 ″ -diamino-p-terphenyl (DATP). The charge ratio (molar ratio) of diamine or pyromellitic dianhydride (PMDA) and pPDA can be appropriately set in consideration of the molecular weight of the desired polyamic acid, the proportion of monomer units, and the like. 1, the acid anhydride component can usually be about 0.7 to 1.3, preferably about 0.8 to 1.2.

On the other hand, the charge ratio of pPDA and DATP, which are diamines, is such that the substance amount (m ¹ ) of pPDA is usually about 1.7 to 20 when the substance amount (m ² ) of DATP is ^1. However, Preferably it is 2.1-20, More preferably, it is 2.2-20, More preferably, it is 2.3-19, More preferably, it is 2.3-18. That is, m ¹ and m ² are usually m ¹ / m ² = 1.7 to 20, preferably 2.1 to 20, more preferably 2.2 to 20, and even more preferably. It is 2.3-19, More preferably, it is 2.3-18.

The above reaction is carried out in an organic solvent. That is, the composition for forming a release layer according to the present invention contains such an organic solvent. Any organic solvent can be used as long as it does not adversely affect the reaction.
Specific examples 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, Protic solvents such as 3-butoxy-N, N-dimethylpropylamide, 3-sec-butoxy-N, N-dimethylpropylamide, 3-tert-butoxy-N, N-dimethylpropylamide, γ-butyrolactone, etc. Can be mentioned. You may use these individually or in combination of 2 or more types.

  According to a preferred embodiment of the present invention, the organic solvent is a solvent represented by the formula (A) or (B).

In formula (A) and formula (B), R ^a and R ^b may be the same or different and each represents an alkyl group having 1 to 4 carbon atoms, preferably 1 to 3 carbon atoms. Here, h represents a natural number, preferably 1 to 3.

What is necessary is just to set reaction temperature suitably in the range from melting | fusing point to boiling point of the solvent to be used, and it is about 0-100 degreeC normally, However, Imidation of the polyamic acid obtained is prevented and high content of a polyamic acid unit is maintained. Therefore, it is preferably about 0 to 70 ° C, more preferably about 0 to 60 ° C, and still more preferably about 0 to 50 ° C.
Although the reaction time depends on the reaction temperature and the reactivity of the raw material, it cannot be defined unconditionally, but is usually about 1 to 100 hours.

  The reaction solution containing the target polyamic acid can be obtained by the method described above.

In the present invention, usually, after filtering the reaction solution, the filtrate is used as it is, or diluted or concentrated, and used as a release layer forming composition. By doing in this way, not only the contamination of the impurity which can cause the deterioration of the heat resistance of the resin thin film obtained, flexibility, or a linear expansion coefficient characteristic can be reduced, but a composition can be obtained efficiently.
The solvent used for dilution and concentration is not particularly limited, and examples thereof include those similar to the specific examples of the reaction solvent in the above reaction, and these may be used alone or in combination of two or more. .

  Among these, considering that a highly flat resin thin film can be obtained with good reproducibility, the solvent used is N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, 1,3. -Dimethyl-2-imidazolidinone, N-ethyl-2-pyrrolidone and γ-butyrolactone are preferred.

  The concentration of the polyamic acid with respect to the total mass of the release layer forming composition is appropriately set in consideration of the thickness of the thin film to be produced (release layer), the composition viscosity, and the like, but is usually about 0.5 to 30% by mass. The amount is preferably about 5 to 25% by mass.

Further, the viscosity of the composition for forming a release layer is also set as appropriate in consideration of the thickness of the thin film to be produced. In particular, the object is to obtain a resin thin film having a thickness of about 0.05 to 5 μm with good reproducibility. In this case, it is usually about 10 to 10,000 mPa · s at 25 ° C., preferably about 20 to 1000 mPa · s, and more preferably about 20 to 200 mPa · s.
Here, the viscosity of the composition for forming a release layer is measured using a commercially available liquid viscosity measurement viscometer, for example, referring to the procedure described in JIS K7117-2, and the temperature of the composition for forming a release layer. It can be measured at 25 ° C. Preferably, a conical plate type (cone plate type) rotational viscometer is used as the viscometer, and preferably 1 ° 34 ′ × R24 is used as a standard cone rotor with the same type viscometer. It can be measured under the condition that the temperature of the product is 25 ° C. An example of such a rotational viscometer is TVE-25H manufactured by Toki Sangyo Co., Ltd.

  In addition, the composition of this invention may have a various component other than a polyamic acid and an organic solvent. Examples thereof include, but are not limited to, a crosslinking agent (hereinafter also referred to as a crosslinkable compound).

  Examples of the crosslinkable compound include a compound containing two or more epoxy groups, a melamine derivative, a benzoguanamine derivative or glycoluril having a hydrogen atom of an amino group substituted with a methylol group, an alkoxymethyl group or both. However, it is not limited to these.

Although the specific example of a crosslinkable compound is given to the following, it is not limited to this.
Examples of the compound containing two or more epoxy groups include cyclohexene structures such as Epolide GT-401, Epolide GT-403, Epolide GT-301, Epolide GT-302, Celoxide 2021, Celoxide 3000 (manufactured by Daicel Corporation). Epoxy compound having: Epicoat 1001, Epicoat 1002, Epicoat 1003, Epicoat 1004, Epicoat 1007, Epicoat 1009, Epicoat 1010, Epicoat 828 (above, manufactured by Japan Epoxy Resin Co., Ltd. (currently, Mitsubishi Chemical Corporation, jER (registered trademark)) Series)), etc .; Bisphenol F type epoxy compounds such as Epicoat 807 (manufactured by Japan Epoxy Resin Co., Ltd.); Epicoat 152, Epicoat 1 4 (above, Japan Epoxy Resin Co., Ltd. (currently, Mitsubishi Chemical Co., Ltd., jER (registered trademark) series), EPPN201, EPPN202 (above, Nippon Kayaku Co., Ltd.) and other phenol novolac epoxy compounds; ECON -102, ECON-103S, ECON-104S, ECON-1020, ECON-1025, ECON-1027 (manufactured by Nippon Kayaku Co., Ltd.), Epicoat 180S75 (Japan Epoxy Resin Co., Ltd. (currently manufactured by Mitsubishi Chemical Corporation) jER (registered trademark) series)) cresol novolac type epoxy compounds; V8000-C7 (made by DIC Corporation) naphthalene type epoxy compounds; Denacol EX-252 (made by Nagase ChemteX Corporation), CY175, CY177, CY179, Ara Daito CY-182, Araldite CY-192, Araldite CY-184 (above, manufactured by BASF), Epicron 200, Epicron 400 (above, made by DIC Corporation), Epicoat 871, Epicoat 872 (above, made by Japan Epoxy Resins Co., Ltd.) (Currently, Mitsubishi Chemical Corporation, jER (registered trademark) series)), ED-5661, ED-5661 (above, made by Celanese Coating Co., Ltd.), etc .; Denacol EX-611, Denacol EX -612, Denacol EX-614, Denacol EX-622, Denacol EX-411, Denacol EX-512, Denacol EX-522, Denacol EX-421, Denacol EX-313, Denacol EX-314, Denacol EX-312 (above, Nagase Chem Aliphatic polyglycidyl ether compounds such as Tex Corporation).

  As the melamine derivative, benzoguanamine derivative, or glycoluril having a group in which the hydrogen atom of the amino group is substituted with a methylol group, an alkoxymethyl group, or both, an average of 3.7 methoxymethyl groups are substituted per triazine ring. MX-750 having an average of 5.8 substituted methoxymethyl groups per triazine ring (above, manufactured by Sanwa Chemical Co., Ltd.); Cymel 300, Cymel 301, Cymel 303, Cymel 350, Methoxymethylated melamines such as Cymel 370, Cymel 771, Cymel 325, Cymel 327, Cymel 703, Cymel 712 and the like; Cymel 235, Cymel 236, Cymel 238, Cymel 212, Cymel 253, Cymel 254 and other methoxymethylated butoxymethylated methy Minol; Butoxymethylated melamine such as Cymel 506, Cymel 508, etc .; Carboxy group-containing methoxymethylated isobutoxymethylated melamine such as Cymel 1141; Methoxymethylated ethoxymethylated benzoguanamine such as Cymel 1123; Methoxymethylated butoxymethylated benzoguanamine; butoxymethylated benzoguanamine such as Cymel 1128; carboxymethyl-containing methoxymethylated ethoxymethylated benzoguanamine such as Cymel 1125-80; butoxymethylated glycoluril such as Cymel 1170; Cymel 1172 Such as methylolated glycoluril (Mitsui Cyanamid Co., Ltd. (currently Japan Cytec Industries Co., Ltd.)) .

  A thin film (peeling layer) made of polyimide having high heat resistance, appropriate flexibility, and appropriate linear expansion coefficient by applying the composition for forming a release layer of the present invention described above to a substrate and heating it. Can be obtained.

  Examples of the base substrate (substrate) include glass, plastic (polycarbonate, polymethacrylate, polystyrene, polyester, polyolefin, epoxy, melamine, triacetyl cellulose, ABS, AS, norbornene resin, etc.), metal (silicon wafer, etc.) Wood, paper, slate and the like.

  The coating method is not particularly limited, but for example, cast coating method, spin coating method, blade coating method, dip coating method, roll coating method, bar coating method, die coating method, ink jet method, printing method (letter plate) , Intaglio, lithographic, screen printing, etc.).

  Moreover, as a method of imidizing the polyamic acid contained in the composition for forming a release layer of the present invention, thermal imidization in which the composition coated on the substrate is heated as it is, and a catalyst is added to the composition and heated. Examples include catalytic imidization.

  The catalyst imidation of polyamic acid is performed by adding a catalyst to the release layer forming composition of the present invention and adjusting the catalyst addition composition by stirring, and then applying and heating the resin thin film (release layer). ) Is obtained. The amount of the catalyst is 0.1 to 30 mol times, preferably 1 to 20 mol times of the amic acid group. Further, acetic anhydride or the like can be added as a dehydrating agent to the catalyst additive composition, and the amount thereof is 1 to 50 mol times, preferably 3 to 30 mol times of the amic acid group.

  A tertiary amine is preferably used as the imidization catalyst. As the tertiary amine, pyridine, substituted pyridines, imidazole, substituted imidazoles, picoline, quinoline, isoquinoline and the like are preferable.

The heating temperature during thermal imidization and catalyst imidation is preferably 450 ° C. or lower. If it exceeds 450 ° C., the resulting resin thin film becomes brittle, and a resin thin film suitable for the intended use may not be obtained.
Moreover, considering the heat resistance and linear expansion coefficient characteristics of the resulting resin thin film, after heating the applied composition at 50 ° C. to 100 ° C. for 5 minutes to 2 hours, the heating temperature is increased stepwise as it is. It is desirable to heat at more than 375 ° C. to 450 ° C. for 30 minutes to 4 hours.
In particular, the applied composition is heated at 50 ° C. to 100 ° C. for 5 minutes to 2 hours, and then is over 100 ° C. to 200 ° C. for 5 minutes to 2 hours, and then is over 200 ° C. to 375 ° C. for 5 minutes to 2 hours. Finally, it is preferable to heat at over 375 ° C. to 450 ° C. for 30 minutes to 4 hours.
Examples of the appliance used for heating include a hot plate and an oven. The heating atmosphere may be under air or under an inert gas, and may be under normal pressure or under reduced pressure.

  When used as a release layer, the thickness of the resin thin film is usually about 0.01 to 10 μm, preferably about 0.05 to 5 μm. The thickness of the coating film before heating is adjusted to a desired thickness. A resin thin film is formed.

  The thin film described above is optimal for use as a peeling layer for peeling without damaging a substrate applied to a flexible electronic device.

  With the composition of the present application, a release layer provided between a flexible substrate applied to a flexible electronic device and a base substrate can be formed. As a base substrate, what contains glass or a silicone wafer is preferable, More preferably, glass is included.

For example, the release layer can be formed by applying the composition of the present invention to a glass substrate by a conventionally known technique and heating the obtained coating film at a predetermined temperature.
Moreover, a to-be-separated body layer can be formed on a peeling layer. The layer to be peeled may be a single layer or a plurality of layers. In order to fabricate various devices, it is realistic to have a plurality of layers.
Of the layer to be peeled, the layer immediately above the release layer depends on the release layer to be used, but it is preferable to use a layer having good peelability with the release layer, in other words, a layer having poor adhesion to the release layer to be used. Good.

As another aspect of the present application, a method for manufacturing an object to be peeled is provided.
The method
a) a step of forming a release layer after applying the composition of the present application on a glass substrate;
b) a step of forming an object to be peeled on the release layer; and c) a step of peeling the object to be peeled at the interface between the release layer and the object to be peeled;
It is possible to obtain an object to be peeled.
In the step b), the “object to be peeled” may be a single layer or a plurality of layers. In addition, although the layer immediately above the release layer of the “object to be peeled” depends on the release layer to be used, the release layer has good peelability, in other words, the adhesiveness to the release layer to be used is not good. There should be.

According to another preferred aspect of the present invention, there is provided a substrate structure applied to a flexible electronic device,
A base substrate;
A release layer covering the base substrate in one or more regions, the release layer formed by the release layer forming composition according to the present invention;
Including the base substrate and a flexible substrate covering the release layer;
A substrate structure is provided in which the adhesive force between the flexible substrate and the release layer is greater than the adhesive force between the release layer and the base substrate. The magnitude | size of an adhesive force here can be confirmed by the crosscut test shown in the Example of this application, for example.

  EXAMPLES Hereinafter, although this invention is demonstrated along an Example, this invention is not limited to this Example.

Abbreviations used in this example are listed and described below.
<Solvent>
NMP: N-methylpyrrolidone.
<Amines>
p-PDA: p-phenylenediamine.
APAB: 2- (3-aminophenyl) -5-aminobenzimidazole.
DATP: 4,4′-diamino-p-terphenyl.
6FAP: 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane.

<Acid dianhydride>
BPDA: 3,3′-4,4′-biphenyltetracarboxylic dianhydride.
BA-TME: 4,4-biphenylenebis (trimellitic acid monoester anhydride).
PMDA: pyromellitic dianhydride.
<Aldehyde>
IPHA: isophthalaldehyde.

[Measurement of number average molecular weight and weight average molecular weight]
The weight average molecular weight (hereinafter abbreviated as “Mw”) and molecular weight distribution of the polymer were determined by using a GPC apparatus (Shodex (registered trademark) columns KF803L and KF805L) manufactured by JASCO Corporation and using dimethylformamide as an elution solvent at a flow rate of 1 ml / min. The measurement was performed at a temperature of 50 ° C. In addition, Mw was made into the polystyrene conversion value.

<Synthesis example>
<Synthesis Example 1 Synthesis of Polyimide Precursor P1>
BPDA (98) // p-PDA (90) / DATP (10)
17.8 g (0.164 mol) of p-PDA, 2.38 g (0.009 mol) of DATP, and 2.05 g (0.009 mol) of APAB were dissolved in 425 g of NMP, and 52.8 g (0.179) of BPDA. Mol) was added at the same time, and 7.4 g of NMP was added again, and the mixture was reacted at 23 ° C. for 24 hours in a nitrogen atmosphere. Mw of the obtained polyimide precursor P1 was 63000 and molecular weight distribution 9.9.

<Synthesis Example 2 Synthesis of Polyimide Precursor P2>
BPDA (98) / DATP (100)
30.8 g (0.118 mol) of DATP was dissolved in 425 g of NMP, 34.1 g (0.116 mol) of BPDA was added at the same time, 10 g of NMP was added again, and the reaction was performed in a nitrogen atmosphere at 23 ° C. for 24 hours. I let you. Mw of obtained polyimide precursor P2 was 70700 and molecular weight distribution 9.7.

<Synthesis Example 3 Synthesis of Polyimide Precursor P3>
PMDA (98) / p-PDA (80) / DATP (20)
p-PDA 20.261 g (0.1875 mol) and TPDA 12.206 g (0.0469 mol) were dissolved in 617.4 g of NMP, cooled to 15 ° C., and PMDA 50.112 g (0.2298 mol) was added. And reacted at 50 ° C. for 48 hours in a nitrogen atmosphere. Mw of the obtained polyimide precursor P3 was 82,100, and molecular weight distribution was 2.7.

<Synthesis Example 4 Synthesis of Polyimide Precursor P4>
BP-TME (98) // p-PDA (95) / APAB (5)
9.66 g (0.089 mol) of p-PDA and 1.05 g (0.005 mol) of APAB were dissolved in 440 g of NMP, 49.2 g (0.092 mol) of BP-TME was added, and under a nitrogen atmosphere, The reaction was allowed to proceed for 24 hours at room temperature. Mw of obtained polyimide precursor P4 was 57000, and molecular weight distribution was 9.3.

<Synthesis Example 5 Synthesis of Polyimide Precursor P5>
BPDA (98) // p-PDA (100)
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. for 24 hours in a nitrogen atmosphere. Mw of the obtained polyimide precursor P5 was 107,300 and molecular weight distribution 4.6.

<Synthesis Example 6 Synthesis of Polybenzoxazole Precursor (P6)>
IHPA (98) / 6/6 FAP (100)
6.18 g (0.059 mol) of 6FAP was dissolved in 70 g of NMP, and 7.92 g (0.060 mol) of IPHA was added thereto, followed by reaction at 23 ° C. for 24 hours in a nitrogen atmosphere. Mw of the obtained polymer was 107,300, and the molecular weight distribution was 4.6.

<Synthesis Example 7 Synthesis of Polyimide Precursor P7>
PMDA (98) // p-PDA (100)
10.078 g (93 mmol) of p-PDA was dissolved in 220.0 g of NMP. PMDA 19.922g (91mmol) was added to the obtained solution, and it was made to react at 23 degreeC under nitrogen atmosphere for 24 hours. The obtained polymer had Mw of 55,900 and a molecular weight distribution of 3.1.

<Preparation of release layer substrate>
P1 to P7 obtained in Synthesis Examples 1 to 7 were diluted to 4 wt% with NMP, applied onto a 100 mm × 100 mm glass substrate (OA-10G non-alkali glass) or silicon wafer using a spin coater, and then cured. Under conditions A to C, baking was performed in an oven to prepare a release layer.
Cure condition A : maintained at 120 ° C. for 30 minutes → temperature increase → 300 ° C. for 60 minutes → temperature increase → 400 ° C. for 60 minutes. The temperature rising rate was 10 ° C./min.
Cure condition B : Maintain at 120 ° C. for 30 minutes → Temperature increase → Maintenance at 180 ° C. for 20 minutes → Temperature increase → Maintenance at 240 ° C. for 20 minutes → Temperature increase → Maintenance at 300 ° C. for 20 minutes → Temperature increase → Maintenance at 400 ° C. for 20 minutes → Temperature rise → Maintained at 450 ° C. for 60 minutes. The temperature rising rate was 10 ° C./min.
Cure condition C : maintained at 80 ° C. for 10 minutes → temperature rise → 300 ° C. for 30 minutes → temperature rise → 400 ° C. for 30 minutes. The temperature rising rate was 10 ° C./min.

The film thickness of the obtained coating film was measured using a contact-type film thickness measuring device (Dektak 3ST manufactured by ULVAC, Inc.).
Table 1 shows the P1-P7 precursors used, the coated substrate, the curing conditions, and the film thickness of the produced release layer.

<Cross cut test I>
About the board | substrate provided with the peeling layer of Examples 1-5 and Comparative Examples 1-3 shown in Table 1, the adhesive force of the board | substrate (glass or silicon wafer) / peeling layer was confirmed by the crosscut test I.
The crosscut test I was performed as follows.
(1) On the film, 100 1 mm squares were produced.
(2) Thereafter, the above square was attached with an adhesive tape (cello tape (registered trademark)), and a peeling process was performed.
(3) After the peeling step, the squares remaining on the substrate were counted.

<Index of results of crosscut test I>
As a result of the cross-cut test, the degree of peeling is indicated by the following index.
5B: Not peeled off.
4B: Peeling of 5% or less.
3B: 5-15% peeling.
2B: 15-35% peel.
1B: 35-65% peeling.
0B: 65% to 80% peeling.
B: 80% to 95% peeling.
A: 95% to less than 100% peeling.
AA: 100% peeling.

  Apart from the cross-cut test I, the characteristics of the components constituting the release layer for the substrates having the release layer of Examples 1 to 5 and Comparative Examples 1 to 3 shown in Table 1, that is, (1) When heated A temperature showing 1% weight loss in weight change of (2), (2) refractive index at a wavelength of 1000 nm, (3) birefringence at a wavelength of 1000 nm, and (4) surface energy were measured. The measurement conditions for each characteristic are shown below.

<(1) Temperature showing a 1% weight reduction in weight change during heating>
Using TD-DTA2000ST manufactured by Bruker Co., Ltd., thermogravimetric (TG) measurement was performed under a nitrogen atmosphere, and the temperature at which the weight decreased by 1% was determined.

<(2) Refractive index at a wavelength of 1000 nm and (3) Birefringence>
The refractive index and the birefringence were measured using a high-speed spectroscopic ellipsometer M-2000 (manufactured by JA Woollam Japan Co., Ltd.). The refractive index was an in-plane refractive index having a value of 1000 nm, and the birefringence was a difference between the in-plane refractive index and the out-of-plane refractive index.

<(4) Surface energy>
The surface energy of each member was measured using a fully automatic contact angle meter DM-701 (manufactured by Kyowa Interface Science Co., Ltd.). In addition, the solvent used for the measurement was water and methylene iodide, and was calculated from the contact angle of these solvents.

<Formation of object to be peeled and peel test (cross-cut test II)>
The to-be-separated body was formed on the board | substrate provided with the peeling layer of Examples 1-5 and Comparative Examples 1-3, and the grade of the peeling was confirmed by the crosscut test II.

<< Preparation of layer to be peeled >>
A polyimide layer was formed as an object to be peeled on the release layer of the substrate provided with the release layer.
Specifically, the precursor P5 obtained in Synthesis Example 5 or Synthesis Example 1 on the release layer of the substrate provided with the release layer of Examples 1 to 5 and Comparative Examples 1 to 3 shown in Table 1. Alternatively, P1 was applied with a bar coater. Then, maintain in an oven at 120 ° C. for 30 minutes → temperature increase → 180 ° C. for 20 minutes → temperature increase → 240 ° C./20 minute maintenance → temperature increase → 300 ° C. for 20 minutes → temperature increase → 400 ° C. for 20 minutes Maintenance → Temperature rise → Cure at 450 ° C. for 60 minutes (the speed was 10 ° C./min at any temperature rise) to produce a 15 μm-thick peeled layer made of polyimide.

<< Crosscut Test II >>
About the board | substrate provided with the to-be-separated body layer and the peeling layer obtained above, the adhesive force between a to-be-separated body layer / peeling layer was confirmed by the crosscut test II.
The crosscut test II was performed in the same manner as the crosscut test I.
Table 2 shows (1) a temperature indicating a 1% weight decrease in weight change during heating (indicated by “(1)” in Table 2), (2) a refractive index at a wavelength of 1000 nm (in Table 2, “ (2) ”, (3) difference between the refractive index and birefringence of (2) (indicated by“ (3) ”in Table 2), (4) surface energy (in Table 2, This is indicated by “(4)” (where the unit is dyne / cm), the polyimide precursor used in the peeled layer, and the results of cross-cut tests I and II.

*: The birefringence of Comparative Example 2 could not be measured.
**: The crosscut test II of Comparative Example 1 and Comparative Example 3 could not be measured due to low adhesion to the release layer and the substrate.

Table 2 shows the following. In the peeling layers of Examples 1 to 5, since the result of Test I is 5B, the peeling layer is not peeled off from the substrate, while the result of Test II is AA. It turns out that only peels. In short, it can be seen that the release layer formed from the composition for release layer of the present invention provides a desired release result.
On the other hand, Comparative Example 1 and Comparative Example 3 show that the release layer peels from the substrate because the result of Test I is AA. In short, it can be seen that Comparative Example 1 and Comparative Example 3 cannot obtain a desired peeling result. In Comparative Example 2, since both Test I and Test II are 5B, neither the interface between the release layer and the substrate nor the interface between the release layer and the layer to be peeled is peeled off. It can be seen that cannot be obtained.

Claims (14)

The composition for peeling layer formation containing the polyamic acid which contains 50 mol% or more of monomer units represented by following formula (1), and whose weight average molecular weight is 10,000 or more, and an organic solvent.

[Wherein, X ¹ represents a tetravalent organic group, and Y ¹ represents a divalent group represented by the following formula (P):

(In the formula, R represents F, Cl, an alkyl group having 1 to 3 carbon atoms, or a phenyl group, m represents an integer of 0 to 4, and r represents an integer of 1 to 4)] . The composition for peeling layer formation of Claim ¹ whose said Y1 is a bivalent group represented by either of following formula (P1)-(P3).

(Where
R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ may be the same or different and represent F, Cl, an alkyl group having 1 to 3 carbon atoms, or a phenyl group,
m1, m2, m3, m4, m5 and m6 may be the same or different and represent an integer of 0 to 4). The composition for forming a release layer according to claim 2, wherein Y ¹ contains at least a divalent group represented by the formula (P1). The composition for peeling layer formation as described in any one of Claims 1-3 in which the said polyamic acid further contains the monomer unit represented by following formula (2).

[Where:
X ¹ is as defined in claim 1 and Y ² represents a group represented by the following formula (P4):

(Where
R ⁷ and R ⁸ may be the same or different and each represents F, Cl, an alkyl group having 1 to 3 carbon atoms, or a phenyl group;
R ′ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a phenyl group,
l represents an integer from 0 to 4 and m is as defined in claim 1)]. Wherein X ¹ is a tetravalent aromatic group, a release layer forming composition according to any one of claims 1 to 4.   The composition according to claim 5, wherein the tetravalent aromatic group has at least one selected from a benzene skeleton, a naphthalene skeleton, and a biphenyl skeleton. The composition according to any one of claims 1 to 6, wherein the organic solvent is a solvent represented by the following formula (A) or (B).

(In the formula, R ^a and R ^b may be the same or different and each represents an alkyl group having 1 to 4 carbon atoms, and h represents a natural number).   The composition for peeling layer formation as described in any one of Claims 1-7 whose content of the monomer unit represented by the said Formula (1) in the said polyamic acid is 60 mol% or more.   In order to form the peeling layer provided directly on a glass substrate, the composition for peeling layer formation as described in any one of Claims 1-8. A release layer formed between a flexible substrate applied to a flexible electronic device and a base substrate,
A release layer produced using the release layer forming composition according to claim 1. A substrate structure applied to a flexible electronic device,
A base substrate;
A release layer covering the base substrate in one or more regions, the release layer formed by the release layer forming composition according to any one of claims 1 to 9,
Including the base substrate and a flexible substrate covering the release layer;
A substrate structure, wherein an adhesion force between the flexible substrate and the release layer is larger than an adhesion force between the release layer and the base substrate.   The substrate structure of claim 11, wherein the base substrate comprises glass.   The manufacturing method of a peeling layer characterized by using the composition for peeling layer formation as described in any one of Claims 1-9. A method for producing a substrate structure applied to a flexible electronic device,
Preparing a base substrate,
The process of producing the peeling layer which covers the said base base | substrate in the area | region of 1 or 2 or more using the composition for peeling layer formation as described in any one of Claims 1-9,
Forming a flexible substrate on the base substrate and the release layer;
The manufacturing method characterized by the adhesive force of the said flexible substrate and the said peeling layer being larger than the adhesive force of the said peeling layer and the said base base | substrate.