CN117279780A

CN117279780A - Laminated substrate, laminated body manufacturing method, laminated body with member for electronic device, and electronic device manufacturing method

Info

Publication number: CN117279780A
Application number: CN202280029474.1A
Authority: CN
Inventors: 山田和夫; 川崎周马
Original assignee: Asahi Glass Co Ltd
Current assignee: AGC Inc
Priority date: 2021-04-22
Filing date: 2022-04-18
Publication date: 2023-12-22
Also published as: KR20240000475A; TW202311032A; JP7371813B2; WO2022224933A1; JPWO2022224933A1

Abstract

The present invention relates to a laminated substrate (10), wherein the laminated substrate (10) comprises: a glass substrate (12), the glass substrate (12) having a first face (12 a) and a second face (12 b) opposite the first face (12 a); and a silicone resin layer (14), wherein the silicone resin layer (14) is disposed on the second surface (12 b) of the glass substrate (12), the surface roughness Ra of the surface (14 a) of the silicone resin layer (14) on the side opposite to the glass substrate (12) varies by 1.00nm or less, and the film thickness of the silicone resin layer (14) varies by 1.5 [ mu ] m or less.

Description

Laminated substrate, laminated body manufacturing method, laminated body with member for electronic device, and electronic device manufacturing method

Technical Field

The present invention relates to a laminated substrate, a laminated body, a method for manufacturing a laminated body, a laminated body with a member for an electronic device, and a method for manufacturing an electronic device.

Background

Electronic devices such as solar cells (PV), liquid crystal panels (LCD), organic electroluminescent panels (OLED), electromagnetic wave induction, X-ray, ultraviolet, visible light, and infrared receiving sensor panels have been increasingly thinned and lightened. Along with this, the thinning of substrates such as polyimide resin substrates used in electronic devices has been advanced. When the strength of the substrate is insufficient due to the thinning, the workability of the substrate is lowered, and problems may occur in a step of forming a member for an electronic device on the substrate (a member forming step), or the like.

Therefore, recently, in order to improve the operability of the substrate, a technique of using a laminate in which a polyimide resin substrate is disposed on a support base material has been proposed (patent document 1). More specifically, patent document 1 discloses that a precision element can be arranged on a cured resin composition layer by applying a polyimide varnish to the cured resin composition layer and forming a cured resin varnish film (corresponding to a polyimide film). In the technique of patent document 1, a cured resin varnish film can be easily peeled from a cured thermosetting resin composition layer, and the cured resin varnish film can be used as a polyimide resin substrate.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open publication No. 2018-193544

Disclosure of Invention

Problems to be solved by the invention

The present inventors have made a polyimide film by the technique described in patent document 1, and as a result, have confirmed that there is an optical unevenness in the polyimide film after peeling from a cured thermosetting resin composition layer functioning as a polysiloxane resin layer that adsorbs and holds the polyimide film. Polyimide films are sometimes used as polyimide resin substrates for transparent electronic devices, and thus improvement of optical unevenness is demanded.

The present invention addresses the problem of providing a laminated substrate that can produce a polyimide film having little optical unevenness when producing a polyimide film by applying a polyimide varnish to the surface of a polysiloxane resin layer and then peeling the polyimide varnish.

The present invention also provides a laminate having the above laminate substrate, a method for producing the laminate, a laminate having a member for an electronic device, and a method for producing an electronic device.

Means for solving the problems

The present inventors have conducted intensive studies and as a result, have found that the above problems can be solved by the following means.

[1] A laminated substrate, the laminated substrate comprising:

a glass substrate having a first face and a second face opposite the first face; and

a silicone resin layer disposed on the second side of the glass substrate, wherein,

the surface of the polysiloxane resin layer on the side opposite to the glass substrate has a variation in surface roughness Ra of 1.00nm or less,

the film thickness of the polysiloxane resin layer varies by 1.5 μm or less.

[2] The laminated substrate according to [1], wherein the average value of the film thickness of the silicone resin layer is 50.0 μm or less.

[3] The laminate substrate according to [1] or [2], wherein a releasable protective film is disposed on the polysiloxane resin layer.

[4] A laminate comprising the laminate substrate of any one of [1] to [3] and a polyimide film disposed on the polysiloxane resin layer of the laminate substrate.

[5] A method for producing a laminate, wherein a polyimide varnish comprising polyimide or a precursor thereof and a solvent is coated on the polysiloxane resin layer of the laminate substrate of any one of [1] to [3] to form a polyimide film on the polysiloxane resin layer, thereby forming a laminate having the glass substrate, the polysiloxane resin layer and the polyimide film.

[6] A laminate with a member for an electronic device, wherein the laminate with a member for an electronic device has:

[4] the laminate, and

and an electronic device member disposed on the polyimide film in the laminate.

[7] A method of manufacturing an electronic device, wherein the method of manufacturing an electronic device comprises:

a member forming step of forming a member for an electronic device on the polyimide film of the laminate of [4], thereby obtaining a laminate with a member for an electronic device; and

And a separation step in which an electronic device having the polyimide film and the member for an electronic device is obtained from the laminate with the member for an electronic device.

Effects of the invention

According to the present invention, a laminated substrate capable of producing a polyimide film having less optical unevenness when the polyimide film is produced by applying a polyimide varnish to the surface of a polysiloxane resin layer and then peeling the polyimide varnish from the polysiloxane resin layer can be provided.

According to the present invention, a laminate having the above laminate substrate, a method for producing a laminate, a laminate with a member for an electronic device, and a method for producing an electronic device can be provided.

Drawings

Fig. 1 is a cross-sectional view schematically showing an embodiment of a laminated substrate of the present invention.

Fig. 2 is a cross-sectional view schematically showing one embodiment of the laminate of the present invention.

Fig. 3 is a diagram for explaining a member forming process.

Fig. 4 is a diagram for explaining the separation step.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the following embodiments are examples for illustrating the present invention, and the present invention is not limited to the embodiments shown below. Various modifications and substitutions can be made to the following embodiments without departing from the scope of the present invention.

The meaning of terms in the present invention is as follows.

The variation of the surface roughness Ra is the difference between the maximum value and the minimum value among 10 measured values obtained by measuring the surface roughness Ra at any 10 points (measurement area: 940 μm long by 700 μm wide) of the surface to be measured.

The average value of the surface roughness Ra is an arithmetic average value of 10 measured values measured according to the above-described operation steps.

The surface roughness Ra is measured, for example, using a non-contact surface/layer cross-sectional shape measuring system "Vertscan R3300-lite" manufactured by rhombic systems Co.

The film thickness variation is the difference between the maximum value and the minimum value among 10 measured values obtained by measuring the film thickness at any 10 points of the object.

The average value of the film thickness is an arithmetic average value of 10 measured values obtained by measuring the fluctuation of the film thickness.

However, in the case of the film thickness of the silicone resin layer, the peripheral region extending 3mm from the peripheral edge portion of the silicone resin layer to the central portion was excluded as the measurement range.

The film thickness is measured by, for example, a contact film thickness measuring device.

The numerical range indicated by the term "to" indicates a range including the numerical values described before and after the term "to" as the lower limit value and the upper limit value.

< laminated substrate >)

Fig. 1 is a cross-sectional view schematically showing an embodiment of a laminated substrate according to the present invention.

The laminated substrate 10 includes: a glass substrate 12, the glass substrate 12 having a first face 12a and a second face 12b opposite the first face 12 a; and a silicone resin layer 14, the silicone resin layer 14 being disposed on the second face 12b of the glass substrate 12.

A polyimide varnish is coated on the polysiloxane resin layer 14 of the laminated substrate 10, and then a polyimide film is formed, which will be described in detail later. An electronic component member is formed on the polyimide film, and then the polyimide film on which the electronic component member is formed (i.e., the electronic component) is separated. Thereby manufacturing an electronic device.

In the laminated substrate 10 shown in fig. 1, the surface roughness Ra of the surface 14a of the polysiloxane resin layer 14 on the side opposite to the glass substrate 12, which is defined below, varies by 1.00nm or less.

If the surface roughness Ra of the surface 14a of the silicone resin layer 14 opposite to the glass substrate 12 varies by 1.00nm or less, a polyimide film with less optical unevenness can be produced by forming the polyimide film on the silicone resin layer 14 of the laminated substrate 10 and then peeling the same.

The surface roughness Ra of the surface 14a of the silicone resin layer 14 opposite to the glass substrate 12 preferably varies by 0.70nm or less, more preferably 0.40nm or less. The lower limit of variation in the surface roughness Ra of the surface 14a of the silicone resin layer 14 opposite to the glass substrate 12 is 0.00nm.

In the laminated substrate 10 shown in fig. 1, the film thickness of the silicone resin layer 14 varies by 1.5 μm or less.

If the film thickness of the silicone resin layer 14 varies by 1.5 μm or less, a polyimide film can be produced with less optical unevenness by forming a polyimide film on the silicone resin layer 14 of the laminated substrate 10 and then peeling it off.

The variation in film thickness of the silicone resin layer 14 is preferably 1.2 μm or less, more preferably 1.0 μm or less. The lower limit of the variation in film thickness of the silicone resin layer 14 is 0.0 μm.

Hereinafter, each layer (glass substrate 12, silicone resin layer 14) constituting the laminated substrate 10 will be described in detail, and then a method for manufacturing the laminated substrate 10 will be described in detail.

(glass substrate)

The glass substrate 12 is a member for supporting and reinforcing the polyimide film.

The glass type is preferably alkali-free borosilicate glass, soda lime glass, silica glass, or other oxide glass containing silica as a main component. The oxide glass is preferably glass having a silicon oxide content of 40 to 90 mass% in terms of oxide.

More specifically, a glass substrate (trade name "AN100" manufactured by AGC corporation) including alkali-free borosilicate glass is exemplified as the glass substrate.

In general, a glass substrate is produced by melting a glass raw material and shaping the molten glass into a plate shape. Such a molding method may be a usual molding method, and examples thereof include a float method, a fusion method, and a flow hole downdraw method.

The shape of the glass substrate 12 (shape of the main surface) is not particularly limited, but is preferably rectangular.

The glass substrate 12 is preferably not flexible. Therefore, the thickness of the glass substrate 12 is preferably 0.3mm or more, more preferably 0.5mm or more.

On the other hand, the thickness of the glass substrate 12 is preferably 1.0mm or less.

(polysiloxane resin layer)

The silicone resin layer 14 is a film for preventing peeling of the polyimide film disposed on the silicone resin layer 14.

The polysiloxane resin layer 14 is disposed on the glass substrate 12.

The polysiloxane resin is a resin containing a predetermined organosiloxane unit, and is generally obtained by curing a curable silicone. Curable silicones are classified into addition reaction type silicones, condensation type silicones, ultraviolet curing type silicones, and electron beam curing type silicones according to the curing mechanism thereof, and any of them can be used. Among them, condensation type silicone is preferable as the polysiloxane resin.

As the condensed type silicone, a hydrolyzable organosilane compound or a mixture thereof (monomer mixture) as a monomer or a partially hydrolyzed condensate (organopolysiloxane) obtained by subjecting a monomer or a monomer mixture to a partial hydrolytic condensation reaction can be suitably used.

By performing hydrolysis/condensation reaction (sol-gel reaction) using the condensed type silicone, a polysiloxane resin can be formed.

The polysiloxane resin layer 14 is preferably formed using a curable composition containing a curable silicone.

The curable composition may contain, in addition to the curable silicone, a solvent, a platinum catalyst (in the case of using an addition reaction type silicone as the curable silicone), a leveling agent, a metal compound, and the like. Examples of the metal element contained in the metal compound include a 3d transition metal, a 4d transition metal, a lanthanoid metal, bismuth (Bi), aluminum (Al), and tin (Sn). The content of the metal compound is not particularly limited and may be appropriately adjusted.

The polysiloxane resin layer 14 preferably has hydroxyl groups. Hydroxyl groups can occur by cleavage of a portion of the Si-O-Si bonds of the polysiloxane resin constituting the polysiloxane resin layer 14. In addition, in the case of using a condensed type silicone, the hydroxyl group can be a hydroxyl group of the silicone resin layer 14.

The average value of the film thickness of the silicone resin layer 14 is preferably 50.0 μm or less, more preferably 30.0 μm or less, and even more preferably 12.0 μm or less. On the other hand, the average value of the film thickness of the silicone resin layer 14 is preferably more than 1 μm, and more preferably 6.0 μm or more from the viewpoint of more excellent foreign matter embedding property.

The excellent embedding property of the foreign matter means that even if the foreign matter exists between the glass substrate 12 and the silicone resin layer 14, the foreign matter is embedded in the silicone resin layer 14.

When the embedding property of the foreign matter is excellent, the convex portion caused by the foreign matter is not easily generated on the polysiloxane resin layer, and when the component for the electronic device is formed on the polyimide film, the risks such as broken wires in the component for the electronic device caused by the convex portion are restrained. Since voids formed when the convex portions were generated were observed as bubbles, the embeddability of foreign matter was evaluated based on the presence or absence of bubbles.

The average value of the surface roughness Ra of the surface 14a of the silicone resin layer 14 is preferably 50.00nm or less, more preferably 30.00nm or less, further preferably 15.00nm or less, and particularly preferably 5.00nm or less. If the average value of the surface roughness Ra of the surface 14a is within the above-described range, the surface roughness of the polyimide film produced by forming on the polysiloxane resin layer 14 of the laminated substrate 10 and then peeling it off is reduced.

In order to maintain adhesion to the polyimide film formed on the silicone resin layer 14, the average value of the surface roughness Ra of the surface 14a of the silicone resin layer 14 is preferably 0.10nm or more, more preferably 0.30nm or more.

When a polyimide film is formed on the glass substrate 12 and subjected to a high-temperature heat treatment, the polyimide film undergoes yellowing, and thus is difficult to apply to transparent electronic devices. However, although the mechanism is not clear, yellowing of the polyimide film due to the high-temperature heat treatment can be suppressed by forming the silicone resin layer 14 on the glass substrate 12 and forming the polyimide film on the silicone resin layer 14.

(protective film)

The laminated substrate 10 may be provided with a releasable protective film on the silicone resin layer 14.

The protective film is a film for protecting the surface of the silicone resin layer 14 before a polyimide varnish described later is applied to the silicone resin layer 14.

Examples of the material constituting the protective film include: polyimide resins, polyester resins (e.g., polyethylene terephthalate, polyethylene naphthalate), polyolefin resins (e.g., polyethylene, polypropylene), polyurethane resins. Among these materials constituting the protective film, polyester resins are preferable, and polyethylene terephthalate is more preferable.

In order to reduce the influence of the force applied from the outside, the average value of the film thickness of the protective film is preferably 20 μm or more, more preferably 30 μm or more, and still more preferably 50 μm or more. The average film thickness of the protective film is preferably 500 μm or less, more preferably 300 μm or less, and even more preferably 100 μm or less.

The protective film may further have an adhesive layer on the surface thereof on the silicone resin layer 14 side.

As the adhesive layer, a known adhesive layer can be used. Examples of the adhesive constituting the adhesive layer include (meth) acrylic adhesives, silicone adhesives, and urethane adhesives.

The adhesive layer may be made of a resin, and examples of the resin include: vinyl acetate resin, ethylene-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate copolymer resin, (meth) acrylic resin, butyral resin, polyurethane resin, polystyrene elastomer.

In order to reduce the peeling force at the time of peeling the protective film, the average value of the surface roughness Ra of the protective film is preferably 50nm or less, more preferably 30nm or less, and still more preferably 15nm or less. In order to maintain the adhesion of the protective film to the silicone resin layer, the average value of the surface roughness Ra of the protective film is preferably 0.1nm or more, more preferably 0.5nm or more.

Method for producing laminated substrate

The method for producing the laminated substrate is not particularly limited, and a known method can be used.

Among them, from the viewpoint of more excellent productivity, the following methods are exemplified: preparing a transfer film having a temporary support and a precursor film which is disposed on the temporary support and becomes a polysiloxane resin layer after heat treatment; attaching the precursor film in the transfer film to a predetermined position on the glass substrate; the resulting laminate having the glass substrate, the precursor film and the temporary support was subjected to a heat treatment. The polysiloxane resin layer is formed by performing a heat treatment.

After the transfer film is bonded to the glass substrate, the resulting laminate may be washed with an alkaline detergent. Further, after washing with an alkaline detergent, washing with pure water may be performed as needed. In addition, after the laminate is rinsed with pure water, moisture may be removed by an air knife as needed. After removing the moisture by the air knife, the laminate may be heat-dried. In addition, in the cleaning, the brush may be brought into contact with the laminate for cleaning. The temperature of the alkaline detergent used in the washing and the temperature of the pure water used in the rinsing are preferably 20 ℃ or higher, more preferably 40 ℃ or higher, from the viewpoint of the washing ability.

In the case of the heat treatment (annealing step) for forming the silicone resin layer, it is preferable to apply pressure while applying pressure. Specifically, the heat treatment and the pressure treatment are preferably performed using an autoclave.

The heating temperature in the heat treatment is preferably 50℃or higher, more preferably 55℃or higher, and still more preferably 60℃or higher. The heating temperature in the heat treatment is preferably 350 ℃ or lower, more preferably 300 ℃ or lower, and further preferably 250 ℃ or lower. The heating time is preferably 10 minutes or more, more preferably 20 minutes or more. The heating time is preferably 60 minutes or less, more preferably 40 minutes or less.

The pressure during the pressure treatment is preferably 0.5 to 1.5MPa, more preferably 0.8 to 1.0MPa.

In addition, the heat treatment may be performed a plurality of times. In the case of performing the heat treatment a plurality of times, the heating conditions of the respective heat treatments may be changed.

For example, in the case of performing the heating treatment a plurality of times, the heating temperature may be changed. For example, in the case of performing the heat treatment 2 times, the first heat treatment may be performed under a temperature condition of less than 200 ℃, and the second heat treatment may be performed under a temperature condition of 200 ℃ or more.

In addition, in the case of performing the heat treatment a plurality of times, the presence or absence of the pressure treatment may be changed. For example, in the case of performing the heating treatment 2 times, the pressurizing treatment may be performed together in the first heating treatment and not performed in the second heating treatment.

In the case of manufacturing a laminated substrate using a transfer film, the above-described heat treatment may be performed after the temporary support is peeled off, or the heat treatment may be performed directly in a state in which the temporary support is disposed on the silicone resin layer. In addition, in the case of performing the heat treatment a plurality of times, the temporary support may be peeled off between the heat treatments. For example, the temporary support may be peeled off after the first heat treatment is performed, and then the second heat treatment may be performed.

In peeling the temporary support, a cutout portion may be formed on the temporary support for easy peeling. In addition, a part of the end portion of the temporary support may be peeled off from the precursor film or the silicone resin layer to form a folded-back portion, which is used as a starting point of peeling off. In addition, a pulling belt may be mounted on the temporary support. In order to facilitate peeling of the temporary support, the temporary support may be made larger than the precursor film or the silicone resin layer, so that the temporary support protrudes, and the temporary support may be peeled by grasping the protruding portion of the temporary support.

In peeling the temporary support, 180 degrees peeling is preferable because there is little possibility that damage is formed on the precursor film or the silicone resin layer to become a defect.

In addition, in order to prevent adhesion of dust caused by peeling electrification, it is preferable to use an ionizer or humidify the peeling environment.

In the heating treatment, a heating furnace such as a circulating furnace or an infrared furnace may be used. In order to remove the gas generated from the silicone resin layer during the heat treatment, the heating furnace is preferably vented. The cleanliness in the heating furnace is preferably 10000 or less.

The surface of the polysiloxane resin layer of the laminated substrate may be subjected to a surface treatment.

Examples of the surface treatment include corona treatment, atmospheric pressure plasma treatment, ultraviolet ozone treatment, and excimer ultraviolet treatment, and corona treatment and atmospheric pressure plasma treatment are preferable.

The water contact angle of the surface 14a of the surface-treated silicone resin layer 14 is preferably 10 degrees or less, more preferably 5 degrees or less.

Using the laminated substrate 10 described above, a structure having the glass base material 12, the silicone resin layer 14, and the supported material in this order can be manufactured. As the supported material, a material other than the polyimide film 18 may be laminated.

Examples of the supported material include: polyimide resin films, epoxy resin films, photoresists, polyester resin films (e.g., polyethylene terephthalate, polyethylene naphthalate), polyolefin resin films (e.g., polyethylene, polypropylene), polyurethane resin films, metal foils (e.g., copper foil, aluminum foil), sputtered films (e.g., copper, titanium, aluminum, tungsten, silicon nitride, silicon oxide, amorphous silicon), TGV substrates, thin plate glass substrates with a sacrificial layer, ABF, sapphire substrates, silicon substrates, TSV substrates, LED chips, display panels (e.g., LCD, OLED, μ -LED), synthetic diamond, interleaving papers, and the like.

Laminate and method for producing the same

Using the laminated substrate 10 described above, a laminate 16 having the glass substrate 12, the silicone resin layer 14, and the polyimide film 18 shown in fig. 2 can be manufactured. The laminate 16 has a polyimide film 18 disposed on the polysiloxane resin layer 14 of the laminate substrate 10.

Specifically, the following method is used as a method for manufacturing the laminate 16: a polyimide varnish containing polyimide and a solvent is applied to the polysiloxane resin layer 14 of the laminated substrate 10, and a polyimide film 18 is formed on the polysiloxane resin layer 14, thereby forming a laminate having the glass substrate 12, the polysiloxane resin layer 14, and the polyimide film 18 in this order.

Hereinafter, the above-described production method will be described in detail, and then, the structure of the polyimide film 18 will be described in detail.

(polyimide varnish)

The polyimide varnish contains polyimide or a precursor thereof and a solvent.

Polyimide is generally obtained by polycondensation and imidization of tetracarboxylic dianhydride and diamine. The polyimide is preferably soluble in a solvent.

As the tetracarboxylic dianhydride to be used, aromatic tetracarboxylic dianhydride and aliphatic tetracarboxylic dianhydride can be mentioned. Examples of the diamine used include aromatic diamine and aliphatic diamine.

Examples of the aromatic tetracarboxylic dianhydride include: 4,4' -diphenyl ether tetracarboxylic dianhydride, 4' -benzophenone tetracarboxylic dianhydride, 2',3,3' -benzophenone tetracarboxylic dianhydride, 3',4,4' -diphenyl ether tetracarboxylic dianhydride, 4' -benzophenone tetracarboxylic dianhydride, 2', 3' -benzophenone tetracarboxylic dianhydride, 3',4,4' -biphenyltetracarboxylic dianhydride, 2, 3',4' -biphenyltetracarboxylic dianhydride, 3',4' -diphenyl sulfone tetracarboxylic dianhydride, 2',3,3' -biphenyltetracarboxylic dianhydride, methylene-4, 4' -diphthalic dianhydride, 1-ethylidene-4, 4' -diphthalic dianhydride, 2-propylidene-4, 4' -diphthalic dianhydride, 1, 2-ethylene-4, 4' -diphthalic dianhydride, 1, 3-trimethylene-4, 4' -diphthalic dianhydride, 1, 4-tetramethylene-4, 4' -diphthalic dianhydride, 1, 5-pentamethylene-4, 4' -diphthalic dianhydride, 4' -oxydiphthalic dianhydride, thio-4, 4' -diphthalic dianhydride, sulfonyl-4, 4' -diphthalic dianhydride, 1, 3-bis (3, 4-dicarboxyphenyl) phthalic dianhydride, 1, 3-bis (3, 4-dicarboxyphenoxy) phthalic dianhydride, 1, 4-bis (3, 4-dicarboxyphenoxy) phthalic dianhydride, 1, 3-bis [2- (3, 4-dicarboxyphenyl) -2-propyl ] benzene dianhydride, 1, 4-bis [2- (3, 4-dicarboxyphenyl) -2-propyl ] benzene dianhydride, bis [3- (3, 4-dicarboxyphenoxy) phenyl ] methane dianhydride, bis [4- (3, 4-dicarboxyphenoxy) phenyl ] methane dianhydride, 2-bis [3- (3, 4-dicarboxyphenoxy) phenyl ] propane dianhydride, 2-bis [4- (3, 4-dicarboxyphenoxy) phenyl ] propane dianhydride, bis (3, 4-dicarboxyphenoxy) dimethylsilane dianhydride 1, 3-bis (3, 4-dicarboxyphenyl) -1, 3-tetramethyldisiloxane dianhydride, 4' -biphenyl bis (trimellitic acid monoester anhydride), 2-bis (3, 4-dicarboxyphenyl) propane dianhydride, 2-bis (2, 3-dicarboxyphenyl) propane dianhydride, bis (3, 4-dicarboxyphenyl) ether dianhydride bis (3, 4-dicarboxyphenyl) sulfone dianhydride, 1-bis (2, 3-dicarboxyphenyl) ethane dianhydride, bis (2, 3-dicarboxyphenyl) methane dianhydride bis (3, 4-dicarboxyphenyl) methane dianhydride, 2-bis (3, 4-dicarboxyphenyl) -1, 3-hexafluoropropane dianhydride, 2, 2-bis (2, 3-dicarboxyphenyl) -1, 3-hexafluoropropane dianhydride, 1, 3-bis [ (3, 4-dicarboxyl) benzoyl ] benzene dianhydride, 1, 4-bis [ (3, 4-dicarboxyl) benzoyl ] benzene dianhydride, 2-bis {4- [4- (1, 2-dicarboxyl) phenoxy ] phenyl } propane dianhydride 2, 2-bis {4- [3- (1, 2-dicarboxy) phenoxy ] phenyl } propane dianhydride, bis {4- [4- (1, 2-dicarboxy) phenoxy ] phenyl } ketone dianhydride, bis {4- [3- (1, 2-dicarboxy) phenoxy ] phenyl } ketone dianhydride, 4 '-bis [4- (1, 2-dicarboxy) phenoxy ] biphenyl dianhydride 4,4' -bis [3- (1, 2-dicarboxy) phenoxy ] biphenyl dianhydride, bis {4- [4- (1, 2-dicarboxy) phenoxy ] phenyl } ketone dianhydride, bis {4- [3- (1, 2-dicarboxy) phenoxy ] phenyl } ketone dianhydride, bis {4- [4- (1, 2-dicarboxy) phenoxy ] phenyl } sulfone dianhydride, bis {4- [3- (1, 2-dicarboxy) phenoxy ] phenyl } sulfone dianhydride, bis {4- [4- (1, 2-dicarboxy) phenoxy ] phenyl } sulfide dianhydride, bis {4- [3- (1, 2-dicarboxy) phenoxy ] phenyl } sulfide dianhydride, 2, 2-bis {4- [4- (1, 2-dicarboxy) phenoxy ] phenyl } -1, 3-hexafluoropropane dianhydride 2, 2-bis {4- [3- (1, 2-dicarboxy) phenoxy ] phenyl } -1, 3-propane dianhydride 2,3,6, 7-naphthalene tetracarboxylic dianhydride, 1,4,5, 8-naphthalene tetracarboxylic dianhydride, 1,2,5, 6-naphthalene tetracarboxylic dianhydride 1,2,3, 4-benzene tetracarboxylic acid dianhydride, 3,4,9, 10-perylene tetracarboxylic acid dianhydride, 2,3,6, 7-anthracene tetracarboxylic acid dianhydride, 1,2,7, 8-phenanthrene tetracarboxylic acid dianhydride, 4' - (hexafluoroisopropylidene) diphthalic anhydride, 5- (2, 5-dioxotetrahydro-3-furyl) -3-methyl-cyclohexene-1, 2-dicarboxylic acid anhydride, pyromellitic acid dianhydride.

Examples of the aliphatic tetracarboxylic dianhydride include cyclic or acyclic aliphatic tetracarboxylic dianhydrides, and examples of the cyclic aliphatic tetracarboxylic dianhydride include: 1,2,3, 4-cyclobutane tetracarboxylic dianhydride, 1,2,3, 4-cyclopentane tetracarboxylic dianhydride, cyclohexane-1, 2,3, 4-tetracarboxylic dianhydride, 1,2,4, 5-cyclohexane tetracarboxylic dianhydride, 1' -bicyclohexane-3, 3',4' -tetracarboxylic acid-3, 4,3',4' -dianhydride, carbonyl-4, 4' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, 1, 2-ethylene-4, 4' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, 1-ethylidene-4, 4' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, 2-propylidene-4, 4' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, oxo-4, 4' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, thioxo-4, 4' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, sulfonyl-4, 4' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, bicyclo [2, 2] oct-7-ene-2, 3,5, 6-tetracarboxylic acid dianhydride, rel- [1S,5R,6R ] -3-oxabicyclo [3,2,1] octane-2, 4-dione-6 ' - (3, 3-tetrahydrofuran-3, 5-dione) -3, 4' -tetrahydrofuran-2, 3' -dione-bis (4, 3' -tetrahydronaphthalene-2, 3' -dicarboxylic acid) dianhydride, 4' -tetramethyl-7-ene-2, 3,5, 6-tetralin-2, 6-tetracarboxylic acid dianhydride, 4,3' -tetramethyl-2, 3-2-dimethylene-2, 5-tetralin, examples of the acyclic aliphatic tetracarboxylic dianhydride include: ethylene tetracarboxylic dianhydride, 1,2,3, 4-butane tetracarboxylic dianhydride, 1,2,3, 4-pentane tetracarboxylic dianhydride, and the like.

Examples of the aromatic diamine include: p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, 2, 4-diaminotoluene, 3' -dimethyl-4, 4' -diaminobiphenyl, 2' -dimethyl-4, 4' -diaminobiphenyl, 3' -diethyl-4, 4' -diaminobiphenyl, 2' -dichloro-4, 4' -diamino-5, 5' -dimethoxybiphenyl, 2',5,5' -tetrachloro-4, 4' -diaminobiphenyl, 3, 7-diamino-dimethyldibenzothiophene-5, 5-dioxide, 4' -bis (4-aminophenyl) sulfide, 1, 3-bis [2- (4-aminophenoxyethoxy) ] ethane, 9-bis (4-aminophenyl) fluorene, 9-bis (4-aminophenoxyphenyl) fluorene, 5 (6) -amino-1- (4-aminomethyl) -1, 3-trimethylindan, 2, 5-bis (4-aminophenoxy) biphenyl 2, 2-bis [4- (4-aminophenoxyphenyl) ] propane, 2-bis (4-aminophenoxyphenyl) hexafluoropropane, 2-bis [4- (4-aminophenoxy) phenyl ] hexafluoropropane, 4' -methylenebis (2-chloroaniline), 9, 10-bis (4-aminophenyl) anthracene, o-tolylsulfone, 3' -diaminodiphenyl ether, 3,4' -diaminodiphenyl ether, 4' -diaminodiphenyl ether, 3,3 '-diaminodiphenyl sulfide, 3,4' -diaminodiphenyl sulfide, 4 '-diaminodiphenyl sulfide, 3' -diaminodiphenyl sulfone, 3,4 '-diaminodiphenyl sulfone, 4' -diaminodiphenyl sulfone, 3 '-diaminobenzophenone, 4' -diaminobenzophenone, and 3,4 '-diaminobenzophenone, 3' -diaminodiphenylmethane, 4 '-diaminodiphenylmethane, 3,4' -diaminodiphenylmethane, 2-bis (3-aminophenyl) propane, 2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 1, 1-bis (3-aminophenyl) -1-phenylethane, 1-bis (4-aminophenyl) -1-phenylethane, 1- (3-aminophenyl) -1- (4-aminophenyl) -1-phenylethane, 1, 3-bis (3-aminophenoxy) benzene, 1, 3-bis (4-aminophenoxy) benzene, 1, 4-bis (3-aminophenoxy) benzene, 1, 4-bis (4-aminophenoxy) benzene, 1, 3-bis (3-aminobenzoyl) benzene, 1, 3-bis (4-aminobenzoyl) benzene, 1, 4-bis (3-aminobenzoyl) benzene, 1, 4-bis (4-aminobenzoyl) benzene, 1, 3-bis (3-amino- α, α -dimethylbenzyl) benzene, 1, 3-bis (4-amino- α, α -dimethylbenzyl) benzene, 1, 4-bis (3-amino- α, α -dimethylbenzyl) benzene, 1, 4-bis (4-amino- α, α -dimethylbenzyl) benzene, 2, 6-bis (3-aminophenoxy) benzonitrile, 2, 6-bis (3-aminophenoxy) pyridine, 4 '-bis (3-aminophenoxy) biphenyl, 4' -bis (4-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl ] ketone, bis [4- (4-aminophenoxy) phenyl ] ketone, bis [4- (3-aminophenoxy) phenyl ] sulfide, bis [4- (4-aminophenoxy) phenyl ] sulfone, bis [4- (3-aminophenoxy) phenyl ] ether, bis [4- (4-aminophenoxy) phenyl ] propane, bis [2, 4-aminophenoxy ] propane, bis [2- (4-aminophenoxy) phenyl ] propane, bis [2, 4-aminophenoxy ] phenyl ] propane 1, 3-bis [4- (4-aminophenoxy) benzoyl ] benzene, 1, 4-bis [4- (3-aminophenoxy) benzoyl ] benzene, 1, 4-bis [4- (4-aminophenoxy) benzoyl ] benzene, 1, 3-bis [4- (3-aminophenoxy) - α, α -dimethylbenzyl ] benzene, 1, 3-bis [4- (4-aminophenoxy) - α, α -dimethylbenzyl ] benzene, 1, 4-bis [4- (3-aminophenoxy) - α, α -dimethylbenzyl ] benzene, 1, 4-bis [4- (4-aminophenoxy) - α, alpha-dimethylbenzyl ] benzene, 4 '-bis [4- (4-aminophenoxy) benzoyl ] diphenyl ether, 4' -bis [4- (4-amino-alpha, alpha-dimethylbenzyl) phenoxy ] benzophenone, 4 '-bis [4- (4-amino-alpha, alpha-dimethylbenzyl) phenoxy ] diphenylsulfone, 4' -bis [4- (4-aminophenoxy) phenoxy ] diphenylsulfone, 3 '-diamino-4, 4' -diphenoxybenzophenone, 3 '-diamino-4, 4' -biphenoxybenzophenone, 3 '-diamino-4-phenoxybenzophenone, 3' -diamino-4-biphenoxybenzophenone, 6,6 '-bis (3-aminophenoxy) -3, 3' -tetramethyl-1, 1 '-spirobiindane, 6' -bis (4-aminophenoxy) -3, 3',3' -tetramethyl-1, 1 '-spirobiindane, 1, 4-diamino-2-fluorobenzene, 1, 4-diamino-2, 3-difluorobenzene, 1, 4-diamino-2, 5-difluorobenzene, 1, 4-diamino-2, 6-difluorobenzene, 1, 4-diamino-2, 3, 5-trifluorobenzene, 1, 4-diamino-2, 3,5, 6-tetrafluorobenzene, 1, 4-diamino-2- (trifluoromethyl) benzene, 1, 4-diamino-2, 3-bis (trifluoromethyl) benzene, 1, 4-diamino-2, 5-bis (trifluoromethyl) benzene, 1, 4-diamino-2, 6-bis (trifluoromethyl) benzene, 1, 4-diamino-2, 3, 5-tris (trifluoromethyl) benzene, 1, 4-diamino-2, 3,5, 6-tetrakis (trifluoromethyl) benzene, 2' -dimethyl benzidine, 2,3, 6-tetrafluoroaniline, 2 '-difluoro benzidine, 3, 6-difluoro benzidine, 2,3' -difluoro benzidine, 3,6 '-difluoro benzidine, 2,3' -difluoro benzidine, 3,6 '-difluoro benzidine, 2,3, 6' -difluoro benzidine; 3-trifluorobenzidine, 2,3 '-trifluorobenzidine, 2', 5-trifluorobenzidine, 2,2', 6-trifluorobenzidine, 2,3', 5-trifluorobenzidine, 2,3', 6-trifluorobenzidine, 2',3 '-tetrafluorobenzidine, 2',5,5 '-tetrafluorobenzidine, 2',6 '-tetrafluorobenzidine, 2', 3', 6' -hexafluorobenzidine, 2', 3', 5',6,6' -octafluorobiphenyl amine, 2- (trifluoromethyl) benzidine, 3- (trifluoromethyl) benzidine, 2, 3-bis (trifluoromethyl) benzidine, 2, 5-bis (trifluoromethyl) benzidine, 2, 6-bis (trifluoromethyl) benzidine, 2,3, 5-tris (trifluoromethyl) benzidine, 2,3, 6-tris (trifluoromethyl) benzidine, 2,3,5, 6-tetrakis (trifluoromethyl) benzidine, 2 '-bis (trifluoromethyl) benzidine, 3' -bis (trifluoromethyl) benzidine, 2', 3-bis (trifluoromethyl) benzidine, 2,3' -tris (trifluoromethyl) benzidine, 2', 5-tris (trifluoromethyl) benzidine, 2', 6-tris (trifluoromethyl) benzidine, 2,3', 5-tris (trifluoromethyl) benzidine, 2,3',6, -tris (trifluoromethyl) benzidine, 2', 3' -tetrakis (trifluoromethyl) benzidine, 2',5,5' -tetra (trifluoromethyl) benzidine, 2', 6' -tetra (trifluoromethyl) benzidine, 1, 4-diaminobenzene, 1, 3-diaminobenzene.

Examples of the aliphatic diamine include: hexamethylenediamine, polyethylene glycol bis (3-aminopropyl) ether, polypropylene glycol bis (3-aminopropyl) ether, bis (aminomethyl) ether, bis (2-aminoethyl) ether, bis (3-aminopropyl) ether, bis [ (2-aminomethoxy) ethyl ] ether, bis [2- (2-aminoethoxy) ethyl ] ether, bis [2- (3-aminopropoxy) ethyl ] ether, 1, 2-bis (aminomethoxy) ethane, 1, 2-bis (2-aminoethoxy) ethane, 1, 2-bis [2- (aminomethoxy) ethoxy ] ethane, 1, 2-bis [2- (2-aminoethoxy) ethoxy ] ethane, ethylene glycol bis (3-aminopropyl) ether diethylene glycol bis (3-aminopropyl) ether, triethylene glycol bis (3-aminopropyl) ether, ethylenediamine, 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 5-diaminopentane, 1, 6-diaminohexane, 1, 7-diaminoheptane, 1, 8-diaminooctane, 1, 9-diaminononane, 1, 10-diaminodecane, 1, 11-diaminoundecane, 1, 12-diaminododecane, 1, 2-cyclohexanediamine, 1, 3-cyclohexanediamine, 1, 4-cyclohexanediamine, trans-1, 4-diaminocyclohexane, 1, 2-bis (2-aminoethyl) cyclohexane, 1, 3-bis (2-aminoethyl) cyclohexane, acyclic aliphatic diamines such as 1, 4-bis (2-aminoethyl) cyclohexane, bis (4-aminocyclohexyl) methane, 2, 6-bis (aminomethyl) bicyclo [2.2.1] heptane, and 2, 5-bis (aminomethyl) bicyclo [2.2.1] heptane; 4,4' -diaminodicyclohexylmethane, 4' -diamino-3, 3' -dimethylcyclohexylmethane, 4' -diamino-3, 3', 5' -tetramethylcyclohexylmethane, 1-amino-3-aminomethyl-3, 5-trimethylcyclohexane, 2-bis (4, 4' -diaminocyclohexyl) propane, 1, 3-diaminomethylcyclohexane, 1, 4-diaminomethylcyclohexane, 2, 3-diaminobicyclo [2.2.1] heptane, 2, 5-diaminobicyclo [2.2.1] heptane, 2, 6-diaminobicyclo [2.2.1] heptane, 2, 7-diaminobicyclo [2.2.1] heptane, 2, 5-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2, 6-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2, 3-bis (aminomethyl) -bicyclo [2.2.1] heptane, 3 (4), cyclic aliphatic diamines such as 8 (9) -bis (aminomethyl) -tricyclo [5.2.1.02,6] decane, 2, 5-bis (aminomethyl) -bicyclo [2.2.1] heptane, 1, 3-bis (3-aminopropyl) tetramethyldisiloxane, 1, 3-bis (4-aminobutyl) tetramethyldisiloxane, α, ω -bis (3-aminopropyl) polydimethylsiloxane, α, ω -bis (3-aminobutyl) polydimethylsiloxane, 1, 3-bis (aminomethyl) cyclohexane, 1, 4-bis (aminomethyl) cyclohexane, norbornanediamine, and the like, and a hydride of the aromatic diamine.

Further, specific examples of the polyimide include a polyimide containing a structural unit A derived from tetracarboxylic dianhydride and a structural unit B derived from diamine, wherein the structural unit A contains a structural unit (A-1) derived from a compound represented by the following formula (a-1) and a structural unit (A-2) derived from a compound represented by the following formula (a-2), and the structural unit B contains a structural unit (B-1) derived from a compound represented by the following formula (B-1) and a structural unit (B-2) derived from a compound represented by the following formula (B-2).

In formula (a-2), L is a single bond or a divalent linking group, and in formula (b-2), R is each independently a hydrogen atom, a fluorine atom or a methyl group.

< structural Unit A >)

The structural unit A is a structural unit derived from tetracarboxylic dianhydride, and comprises a structural unit (A-1) derived from a compound represented by the formula (a-1) and a structural unit (A-2) derived from a compound represented by the formula (a-2).

The compound represented by the formula (a-1) is norbornane-2-spiro-alpha-cyclopentanone-alpha' -spiro-2 "-norbornane-5, 5",6 "-tetracarboxylic dianhydride.

In formula (a-2), L is a single bond or a divalent linking group. The divalent linking group is preferably a substituted or unsubstituted alkylene group, more preferably-CR ₁ R ₂ - (here, R) ₁ And R is ₂ Each independently is a hydrogen atom or a substituted or unsubstituted alkyl group, or R ₁ And R is ₂ Bonded to each other to form a ring. ).

L is preferably selected from the group consisting of a single bond, a group represented by the following formula (L-1), and a group represented by the following formula (L-2).

In the formula (L-1) and the formula (L-2), the connection site is shown.

The structural unit (A-2) is preferably at least one structural unit selected from the group consisting of a structural unit (A-2-1) derived from a compound represented by the following formula (a-2-1), a structural unit (A-2-2) derived from a compound represented by the following formula (a-2-2), and a structural unit (A-2-3) derived from a compound represented by the following formula (a-2-3), and more preferably at least one structural unit selected from the group consisting of a structural unit (A-2-1) and a structural unit (A-2-2).

The compound represented by the formula (a-2-1) is biphenyltetracarboxylic dianhydride, and specific examples thereof include: 3,3',4' -biphenyltetracarboxylic dianhydride, 2, 3',4' -biphenyltetracarboxylic dianhydride, 2', 3' -biphenyltetracarboxylic dianhydride.

The compound represented by the formula (a-2-2) is 9,9' -bis (3, 4-dicarboxyphenyl) fluorene dianhydride.

The compound represented by the formula (a-2-3) is 4,4' - (hexafluoroisopropylidene) diphthalic anhydride.

The content of the structural unit (a-1) in the structural unit a is preferably 50 mol% or more, more preferably 55 mol% or more, still more preferably 60 mol% or more, and particularly preferably 75 mol% or more. The content of the structural unit (A-1) in the structural unit A is preferably 95 mol% or less.

The content of the structural unit (a-2) in the structural unit a is preferably 50 mol% or less, more preferably 45 mol% or less, further preferably 40 mol% or less, particularly preferably 25 mol% or less. The lower limit of the content of the structural unit (A-2) in the structural unit A is preferably 5 mol% or more.

The total content of the structural units (A-1) and (A-2) in the structural unit A is preferably 55 mol% or more, more preferably 60 mol% or more, still more preferably 65 mol% or more, and particularly preferably 80 mol% or more. The upper limit of the total content of the structural units (A-1) and (A-2) is not particularly limited, that is, 100 mol% or less. The structural unit A may be composed of only the structural unit (A-1) and the structural unit (A-2).

The structural unit A may contain structural units other than the structural units (A-1) and (A-2).

The tetracarboxylic dianhydride forming such a structural unit is not particularly limited, and examples thereof include: aromatic tetracarboxylic dianhydrides such as pyromellitic dianhydride (excluding the compounds represented by the formula (a-2)); alicyclic tetracarboxylic dianhydrides such as 1,2,3, 4-cyclobutane tetracarboxylic dianhydride and 1,2,4, 5-cyclohexanedicarboxylic dianhydride (excluding the compound represented by the formula (a-1)); aliphatic tetracarboxylic dianhydrides such as 1,2,3, 4-butanetetracarboxylic dianhydride.

The aromatic tetracarboxylic dianhydride means a tetracarboxylic dianhydride containing 1 or more aromatic rings, the alicyclic tetracarboxylic dianhydride means a tetracarboxylic dianhydride containing 1 or more alicyclic rings and not containing an aromatic ring, and the aliphatic tetracarboxylic dianhydride means a tetracarboxylic dianhydride containing neither aromatic nor alicyclic rings.

The structural units (i.e., the structural units other than the structural units (A-1) and (A-2)) arbitrarily contained in the structural unit A may be one kind or two or more kinds.

< structural Unit B >)

The structural unit B is a structural unit derived from diamine, and comprises a structural unit (B-1) derived from a compound represented by the formula (B-1) and a structural unit (B-2) derived from a compound represented by the formula (B-2). The structural unit (B-1) improves mechanical properties and dimensional stability, and the structural unit (B-2) improves heat resistance.

The compound represented by the formula (b-1) is 2,2' -bis (trifluoromethyl) benzidine.

In the formula (b-2), each R is independently selected from the group consisting of a hydrogen atom, a fluorine atom and a methyl group, preferably a hydrogen atom. As the compound represented by the formula (b-2), there may be mentioned: 9, 9-bis (4-aminophenyl) fluorene, 9-bis (3-fluoro-4-aminophenyl) fluorene, 9-bis (3-methyl-4-aminophenyl) fluorene, and the like, preferably 9, 9-bis (4-aminophenyl) fluorene.

The content of the structural unit (B-1) in the structural unit B is preferably 20 mol% or more, more preferably 45 mol% or more, and still more preferably 50 mol% or more. The content of the structural unit (B-1) in the structural unit B is preferably 90 mol% or less, more preferably 85 mol% or less, and further preferably 80 mol% or less.

The content of the structural unit (B-2) in the structural unit B is preferably 10 mol% or more, more preferably 15 mol% or more, and still more preferably 20 mol% or more. The content of the structural unit (B-2) in the structural unit B is preferably 80 mol% or less, more preferably 55 mol% or less, and further preferably 50 mol% or less.

The total content of the structural units (B-1) and (B-2) in the structural unit B is preferably 30 mol% or more, more preferably 60 mol% or more, and still more preferably 70 mol% or more. The upper limit of the total content of the structural units (B-1) and (B-2) is not particularly limited, that is, 100 mol% or less. The structural unit B may be composed of only the structural unit (B-1) and the structural unit (B-2).

The structural unit B may contain structural units other than the structural units (B-1) and (B-2). The diamine forming such a structural unit is not particularly limited, and examples thereof include the aromatic diamine (excluding the compound represented by the formula (b-1) and the compound represented by the formula (b-2)), the alicyclic diamine, and the aliphatic diamine.

The structural units (B) may be any of the structural units (B-1) and (B-2), or may be any of the structural units (B-2).

In addition, since the fluorene skeleton of 9-bis (4-aminophenyl) fluorene, 9-bis (4-aminophenoxyphenyl) fluorene has negative intrinsic birefringence, polyimide may have a structural unit derived from 9-bis (4-aminophenyl) fluorene, 9-bis (4-aminophenoxyphenyl) fluorene in order to adjust retardation of polyimide film.

In addition, in the case of the optical fiber, 2,2' -bis (trifluoromethyl) benzidine, 3' -bis (trifluoromethyl) -4,4' -diaminobiphenyl, 2' -bis [3 (3-aminophenoxy) phenyl ] hexafluoropropane, 2' -bis [4 (4-aminophenoxy) phenyl ] hexafluoropropane, 2' -bis (3-aminophenyl) hexafluoropropane, 2' -bis (4-aminophenyl) hexafluoropropane can inhibit the formation of charge transfer complexes between polyimide molecules by introducing bulky steric hindrance of fluorine atoms. Thus, in order to reduce the Yellowness Index (YI) of the polyimide film, the polyimide may have repeating units derived from the above.

The precursor of polyimide means polyamic acid (so-called polyamic acid and/or polyamic acid ester) in a state before imidization.

Specific examples of the precursor of polyimide include: a polyimide precursor containing 50 mol% or more of a structural unit represented by the following formula (1A) with respect to the entire structural units, and a polyimide precursor containing 50 mol% or more of a structural unit represented by the following formula (1A) and a structural unit represented by the following formula (2A) with respect to the entire structural units.

In formula (1A), R ₁ 、R ₂ Each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.

In formula (2A), R ₃ 、R ₄ Each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.

Specific examples of the precursor of polyimide include: a precursor of polyimide containing preferably 90 mol% or more, more preferably 95 mol% or more of the structural unit represented by the following formula (3A) with respect to the entire structural units; the precursor of polyimide containing 90 mol% or more, more preferably 95 mol% or more of the structural unit represented by the following formula (3A) and the structural unit represented by the following formula (4A) with respect to the entire structural units is preferable.

In the formula (3A), A ₁ Is a divalent group having an aromatic ring, R ₅ 、R ₆ Each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.

In the formula (4A), A ₂ Is a divalent group having an aromatic ring, R ₇ 、R ₈ Each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.

The structural unit represented by formula (1A) is wherein A ₁ A structural unit represented by formula (3A) which is a group represented by the following formula (D-1).

The structural unit represented by formula (2A) is wherein A ₂ A structural unit represented by formula (4A) which is a group represented by the following formula (D-1).

A in formula (3A) other than the group represented by formula (D-1) ₁ And A in formula (4A) ₂ The divalent group having an aromatic ring having 6 to 40 carbon atoms is preferable, and the group represented by the following formula (a-1) is more preferable.

In the formula, m represents 0 to 3, and n represents 0 to 3.Y is Y ₁ 、Y ₂ 、Y ₃ Each independently represents one selected from the group consisting of a hydrogen atom, a methyl group and a trifluoromethyl group, Q, R is each independently directly bonded or represents a group selected from the group consisting of formula (la): -NHCO-, -CONH-, -COO-and-OCO-in the presence of a reactive group.

As the tetracarboxylic acid component providing the structural unit represented by the formula (1A) and the structural unit represented by the above formula (3A), there are 1,2,3, 4-cyclobutane tetracarboxylic acids and the like. As the tetracarboxylic acids, there may be mentioned: tetracarboxylic acid and tetracarboxylic dianhydride, tetracarboxylic silyl ester, tetracarboxylic acid chloride, and the like.

As the tetracarboxylic acid component providing the structural unit represented by the formula (2A), there can be mentioned: trans-endo-norbornane-2-spiro-alpha-cyclopentanone-alpha ' -spiro-2 "-norbornane-5, 5",6 "-tetracarboxylic acids, cis-endo-norbornane-2-spiro-alpha-cyclopentanone-alpha ' -spiro-2" -norbornane-5, 5", 6" -tetracarboxylic acids and the like norbornane-2-spiro-alpha-cyclopentanone-alpha ' -spiro-2 "-norbornane-5, 5",6 "-tetracarboxylic acids.

As the diamine component providing the structural unit represented by the formula (1A) and the structural unit represented by the formula (2A), there is, for example, 2 '-dimethyl-4, 4' -diaminobiphenyl (m-toluidine).

Providing wherein A ₁ Structural unit of formula (3A) which is a group represented by formula (A-1) and wherein A ₂ The diamine component of the structural unit of formula (4A), which is a group represented by formula (A-1), has an aromatic ring, and when there are a plurality of aromatic rings, the aromatic rings are each independently connected by direct bonding, an amide bond or an ester bond. The connection position between the aromatic rings is not particularly limited, and the polyimide obtained by bonding the connection group between the amino group and the aromatic rings at the 4-position may have a linear structure, and may have low linear thermal expansion. In addition, a methyl group and a trifluoromethyl group may be substituted on the aromatic ring. The substitution position is not particularly limited.

As provided wherein A ₁ Structural unit of formula (3A) which is a group represented by formula (A-1) and wherein A ₂ Is prepared from1) The diamine component of the structural unit of formula (4A) of the group represented by formula (I) may be: p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, benzidine, 3' -diamino-biphenyl, 2' -bis (trifluoromethyl) benzidine, 3' -bis (trifluoromethyl) benzidine, 4' -diaminobenzanilide, 3,4' -diaminobenzanilide, N ' -bis (4-aminophenyl) terephthalamide, N, N ' -p-phenylene bis (p-aminobenzamide), 4-aminophenoxy-4-diaminobenzoate, bis (4-aminophenyl) terephthalate, bis-4, 4' -dicarboxylic acid bis (4-aminophenyl) ester, p-phenylene bis (p-aminobenzoate), bis (4-aminophenyl) - [1,1' -biphenyl]-4,4 '-dicarboxylic acid ester, [1,1' -biphenyl ]]-4,4' -diylbis (4-aminobenzoate), and the like.

As the diamine component providing the structural unit of formula (3A) or formula (4A), other than providing A may be used ₁ Or A ₂ An aromatic diamine other than the diamine component which is a structural unit of the formula (D-1) or the formula (A-1).

Examples of the other diamine component include: 3,3 '-bis (trifluoromethyl) benzidine, 3' -bis ((aminophenoxy) phenyl) propane, 2 '-bis (3-amino-4-hydroxyphenyl) hexafluoropropane bis (4- (4-aminophenoxy) diphenyl) sulfone, bis (4- (3-aminophenoxy) diphenyl) sulfone 3,3' -bis (trifluoromethyl) benzidine, 3 '-bis ((aminophenoxy) phenyl) propane, 2' -bis (3-amino-4-hydroxyphenyl) hexafluoropropane, bis (4- (4-aminophenoxy) diphenyl) sulfone, bis (4- (3-aminophenoxy) diphenyl) sulfone octafluorobiphenyl, 3 '-dimethoxy-4, 4' -diaminobiphenyl, 3 '-dichloro-4, 4' -diaminobiphenyl, 3 '-difluoro-4, 4' -diaminobiphenyl, 6 '-bis (3-aminophenoxy) -3, 3',3 '-tetramethyl-1, 1' -spirobiindane, 6 '-bis (4-aminophenoxy) -3, 3', examples of the 3' -tetramethyl-1, 1' -spirobiindane and the like and derivatives thereof include polyimide precursors obtained from tetracarboxylic acid components containing 1,2,3, 4-cyclobutane tetracarboxylic acid and the like, or from tetracarboxylic acid components containing 1,2,3, 4-cyclobutane tetracarboxylic acid and the like and norbornane-2-spiro- α -cyclopentanone- α ' -spiro-2 "-norbornane-5, 5",6 "-tetracarboxylic acid and the like, and from diamine components containing 2,2' -dimethyl-4, 4' -diaminobiphenyl (meta-toluidine).

The solvent may be any solvent that dissolves polyimide or a precursor thereof, and examples thereof include: phenolic solvents (e.g., m-cresol), amide solvents (e.g., N-methyl-2-pyrrolidone, N-dimethylformamide, N-dimethylacetamide), lactone solvents (e.g., γ -butyrolactone, δ -valerolactone, ε -caprolactone, γ -crotonlactone, γ -caprolactone, α -methyl- γ -butyrolactone, γ -valerolactone, α -acetyl- γ -butyrolactone, δ -caprolactone), sulfoxide solvents (e.g., N-dimethyl sulfoxide), ketone solvents (e.g., acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ester solvents (e.g., methyl acetate, ethyl acetate, butyl acetate, dimethyl carbonate).

The polyimide varnish preferably contains 5 to 40 mass% of a polyimide resin or a precursor thereof, and more preferably contains 10 to 30 mass% of a polyimide resin or a precursor thereof. The viscosity of the polyimide varnish is preferably 1pa·s to 200pa·s, more preferably 5pa·s to 150pa·s.

(operation procedure)

The method of applying the polyimide varnish to the silicone resin layer 14 side of the laminated substrate 10 is not particularly limited, and a known method may be used. Examples include: slit coating, curtain coating, spray coating, die coating, spin coating, dip coating, roll coating, bar coating, screen printing, gravure coating.

After the application, a heat treatment (curing step) may be performed as needed.

The heating treatment is preferably carried out at a temperature of 50 to 500 ℃, more preferably 50 to 450 ℃. The heating time is preferably 10 minutes to 300 minutes, more preferably 20 minutes to 200 minutes.

In order to planarize the particles and the protrusions, the surface of the polyimide film after formation may be polished.

The laminated substrate may be washed with an alkaline detergent before the polyimide varnish is applied. Further, after washing with an alkaline detergent, washing with pure water may be performed as needed. In addition, after rinsing with pure water, moisture may be removed by an air knife as needed. After removing the moisture by the air knife, heat drying may be performed. Since the surface of the silicone resin layer may be damaged by contact with the brush, it is preferable to perform cleaning without contact with the brush during cleaning.

The laminated substrate before the polyimide varnish was coated can be inspected for surface quality in the same manner as the glass substrate.

(laminate)

As shown in fig. 2, the laminate 16 has a glass substrate 12, a silicone resin layer 14, and a polyimide film 18.

The glass substrate 12 and the silicone resin layer 14 are constructed as described above.

Polyimide film 18 is disposed on polysiloxane resin layer 14.

The average film thickness of the polyimide film 18 is preferably 1 μm or more, more preferably 5 μm or more. From the viewpoint of flexibility, the average value of the film thickness of the polyimide film 18 is preferably 1mm or less, more preferably 0.2mm or less.

The variation in film thickness of the polyimide film 18 is preferably 0.5 μm or less, more preferably 0.2 μm or less. As the lower limit, 0 μm can be cited.

The polyimide film 18 may be a single-layer film or a multilayer film having 2 or more layers.

In order to form high-definition wiring or the like of an electronic device on the polyimide film 18, it is preferable that the surface of the polyimide film 18 be smooth. Specifically, the average value of the surface roughness Ra of the polyimide film 18 is preferably 50nm or less, more preferably 30nm or less, and even more preferably 10nm or less. As the lower limit, 0nm can be cited.

When the difference between the coefficient of thermal expansion of the polyimide film 18 and the coefficient of thermal expansion of the glass substrate 12 is small, warpage of the laminate 16 after heating or cooling can be suppressed, and thus it is preferable. Specifically, the difference between the thermal expansion coefficients of the polyimide film 18 and the glass substrate 12 is preferably 0 to 90×10 ^-6 Preferably 0 to 30X 10 per DEG C ^-6 /℃。

The area of the polyimide film 18 is not particularly limited, but is preferably 300cm from the viewpoint of productivity of electronic devices ² The above.

The Yellowness Index (YI) of the polyimide film 18 is preferably small. The YI of the polyimide film 18 is preferably 10.0 or less, more preferably 5.0 or less, further preferably 3.5 or less, and particularly preferably 1.5 or less. As the lower limit, 0 may be cited.

YI was measured according to JIS K7361-1.

The polyimide film 18 preferably has a light transmittance in the visible light region of 80% or more. The upper limit is less than 100%.

The laminate may have a gas barrier film on the polyimide film 18. In the case where the polyimide film 18 is a laminated film, a gas barrier film may be provided between two or more layers.

Examples of the gas barrier film include inorganic material films such as a silicon oxide film and a silicon nitride film. The gas barrier film may be a multilayer film in which an organic material layer such as a thermoplastic resin or an organosilicon compound and an inorganic material layer such as silicon oxide or silicon nitride are laminated. The film forming method is not particularly limited, and known methods can be used. For example, methods such as plasma CVD and sputtering can be used.

The laminate 16 can be used for various applications, for example, applications for manufacturing electronic components such as a panel for a display device, a PV, a thin film secondary battery, a semiconductor wafer having a circuit formed on the surface, and a receiving sensor panel, which will be described later. In these applications, the laminate is sometimes exposed to high temperature conditions (e.g., 450 ℃ or higher) (e.g., 20 minutes or higher) under an atmospheric atmosphere.

The panel for display device includes LCD, OLED, electronic paper, plasma display panel, field emission panel, quantum dot LED panel, micro LED display panel, MEMS shutter panel, and the like.

The receiving sensor panel includes: an electromagnetic wave receiving sensor panel, an X-ray receiving sensor panel, an ultraviolet ray receiving sensor panel, a visible light receiving sensor panel, an infrared ray receiving sensor panel, and the like. The substrate for receiving the sensor panel may be reinforced by a reinforcing sheet of resin or the like.

Method for manufacturing electronic device

An electronic device including a polyimide film and a member for an electronic device described later was manufactured using the laminate.

The method of manufacturing an electronic device is, for example, as shown in fig. 3 and 4, a method having the steps of: a member forming step of forming an electronic component member 20 on a surface of the polyimide film 18 of the laminate 16 on the side opposite to the polysiloxane resin layer 14 side, thereby obtaining a laminate 22 with the electronic component member; and a separation step in which an electronic device 24 having the polyimide film 18 and the electronic device member 20 is obtained from the laminate 22 with the electronic device member.

Hereinafter, the step of forming the member for electronic device 20 will be referred to as a "member forming step", and the step of separating the member into the electronic device 24 and the glass substrate 26 having the polysiloxane resin layer will be referred to as a "separating step".

Hereinafter, materials and operation steps used in each step will be described in detail.

(component Forming step)

The member forming step is a step of forming a member for an electronic device on the polyimide film 18 of the laminate 16. More specifically, as shown in fig. 3, an electronic component member 20 is formed on the surface of the polyimide film 18 on the side opposite to the polysiloxane resin layer 14 side, thereby obtaining a laminate 22 with the electronic component member. The laminate 22 with the electronic component member includes the laminate 16 and the electronic component member 20 disposed on the polyimide film 18 in the laminate 16.

First, the electronic component member 20 used in this step will be described in detail, and the operation steps of the subsequent steps will be described in detail.

(Member for electronic device)

The electronic component member 20 is a member constituting at least a part of an electronic component formed on the polyimide film 18 of the laminate 16.

More specifically, as the member 20 for electronic devices, there may be mentioned: an electronic component such as a panel for a display device, a solar cell, a thin film secondary battery, or a semiconductor wafer having a circuit formed on a surface thereof, a member used for receiving a sensor panel or the like (for example, a member for a display device such as LTPS (low temperature polysilicon), a member for a solar cell, a member for a thin film secondary battery, a circuit for an electronic component, a member for a receiving sensor), a member for a solar cell described in, for example, paragraph [0192] of U.S. patent application publication No. 2018/0178492, a member for a thin film secondary battery described in paragraph [0193] of the specification, and a circuit for an electronic component described in paragraph [0194] of the specification).

(operation procedure of the step)

The method for producing the laminate 22 with the electronic device member is not particularly limited, and the electronic device member 20 is formed on the polyimide film 18 of the laminate 16 by a conventionally known method according to the kind of the constituent member of the electronic device member.

The component 20 for an electronic device may be not all of the components (hereinafter, referred to as "all components") that are finally formed on the polyimide film 18, but a part of all the components (hereinafter, referred to as "part components"). The substrate with a part of the members peeled from the silicone resin layer 14 can be made into a substrate with all the members (corresponding to an electronic device described later) in a subsequent step.

Other members for electronic devices may be formed on the release surface of the substrate with all the members released from the silicone resin layer 14. Further, an electronic device can be manufactured by assembling a laminate with all members by facing 2 pieces of the electronic device members 20 of the laminate with electronic device members 22, bonding the two members to each other, and then peeling 2 pieces of the glass base material with a silicone resin layer from the laminate with all members.

For example, in the case of manufacturing an OLED (organic light emitting diode), in order to form an organic EL structure on the surface of the polyimide film 18 of the laminate 16 on the side opposite to the polysiloxane resin layer 14 side, the following various layer formation or treatment is performed: forming a transparent electrode; evaporating a hole injection layer/a hole transport layer/a light emitting layer/an electron transport layer on the surface where the transparent electrode is formed; forming a back electrode; sealing with a sealing plate, and the like. Specific examples of the layer formation or treatment include a film formation treatment, a vapor deposition treatment, and a sealing plate adhesion treatment.

(separation step)

As shown in fig. 4, the separation process is as follows: the interface between the silicone resin layer 14 and the polyimide film 18 is used as a release surface, and the polyimide film 18 on which the electronic component member 20 is laminated and the glass substrate 26 on which the silicone resin layer is laminated are separated from the laminate 22 with the electronic component member obtained in the above-described member forming step, thereby obtaining the electronic component 24 including the electronic component member 20 and the polyimide film 18.

In the case where the electronic component member 20 on the peeled polyimide film 18 is a part of all the necessary constituent members, the remaining constituent members may be formed on the polyimide film 18 after separation.

The method of peeling the polyimide film 18 from the polysiloxane resin layer 14 is not particularly limited. For example, after a sharp blade is inserted at the interface between the polyimide film 18 and the glass substrate 12 to generate the start of peeling, a mixed fluid of water and compressed air or the like may be blown to peel. In addition, a laser lift-off method may be used.

As a method of peeling the polyimide film 18 from the polysiloxane resin layer 14, it is preferable that: the laminate 22 with the electronic component member is set on a stage with the glass substrate 12 on the upper side and the electronic component member 20 on the lower side, and the electronic component member 20 is vacuum-sucked on the stage, and in this state, the blade is first brought into the interface between the polyimide film 18 and the glass substrate 12. Then, the glass substrate 12 side is sucked by a plurality of vacuum chucks, and the vacuum chucks are sequentially lifted from the vicinity of the position where the blade is inserted. Thereby enabling easy peeling of the glass substrate 26 with the polysiloxane resin layer.

In the case where the electronic component member 20 is produced for each of the plurality of units when the polyimide film 18 and the silicone resin layer 14 are peeled off, the electronic component 24 having the polyimide film 18 and the electronic component member 20 may be cut for each unit, and then the polyimide film 18 and the silicone resin layer 14 may be peeled off for each unit after the cutting. As a method of cutting each unit, there can be mentioned: a method of cutting by a laser beam, a method of cutting by a cutting machine such as a dicing saw, or the like.

When the electronic component 24 is separated from the laminate 22 with the electronic component member, the electrostatic adsorption of the chips of the silicone resin layer 14 to the electronic component 24 can be further suppressed by controlling the blowing by the ionizer and the humidity.

The method for manufacturing an electronic device is suitable for manufacturing a display device described in, for example, paragraph [0210] of U.S. patent application publication No. 2018/0178492, and examples of the electronic device 24 include the electronic device described in paragraph [0211] of this specification.

The region of the laminate where the electronic component member is not disposed may be cut and removed before the separation step is performed.

A protective film may be attached to the surface of the electronic component member 20 of the separated electronic component 24 on the side opposite to the polyimide film 18 side.

A protective film may be attached to the surface of the polyimide film 18 of the separated electronic device 24 on the opposite side of the electronic device member 20 side. Before the protective film is attached to the polyimide film 18, the surface of the polyimide film 18 may be subjected to a surface treatment as needed. Examples of the surface treatment include: corona treatment, atmospheric pressure plasma treatment, ultraviolet ozone treatment, and excimer ultraviolet treatment. The water contact angle of the surface of the polyimide film 18 after the surface treatment is preferably 10 degrees or less, more preferably 5 degrees or less.

The glass substrate 2 with a polysiloxane resin layer separated from the laminate 22 with an electronic device member can also be recovered and reused as a glass raw material.

The surface of the polysiloxane resin layer 14 of the glass substrate 26 with a polysiloxane resin layer thus separated may be cleaned and then surface-modified, and may be used again as a laminated substrate for forming a polyimide film.

The silicone resin layer 14 of the separated glass substrate 26 with a silicone resin layer may be removed and reused as a glass substrate. As a method for removing the silicone resin layer, there can be mentioned: a method of dissolving a silicone resin layer in a solvent, and a method of mechanically grinding or polishing a silicone resin layer.

Examples

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Hereinafter, as a glass substrate, a glass substrate comprising an alkali-free borosilicate glass (linear expansion coefficient 38×10 ^-7 At a temperature of "C", trade name "AN100" manufactured by AGC Co., ltd.

Examples 1 to 4, 9 and 10 are examples, examples 5 to 8 and examples 11 to 15 are comparative examples.

(preparation of curable Silicone 1)

Triethoxymethylsilane (179 g), toluene (300 g), acetic acid (5 g) were charged into a 1L flask, and the mixture was stirred at 25℃for 20 minutes, and then further heated to 60℃to react for 12 hours. The resulting reaction crude liquid was cooled to 25℃and then washed 3 times with water (300 g). To the washed reaction crude liquid was added trimethylchlorosilane (70 g), and the mixture was stirred at 25℃for 20 minutes, and then further heated to 50℃to react for 12 hours. The resulting reaction crude liquid was cooled to 25℃and then washed 3 times with water (300 g).

Toluene was distilled off under reduced pressure from the reaction crude liquid after washing to prepare a slurry state, and then dried overnight by a vacuum dryer, whereby curable silicone 1 was obtained as a white organopolysiloxane compound. Number of T units of curable silicone 1: number of M units = 87:13 (molar ratio). The molar ratio of M units to T units in the curable silicone 1 was 13:87, the organic groups were all methyl groups, the average number of OX groups was 0.02. The average number of OX groups is a number indicating how many OX groups (X is a hydrogen atom or a hydrocarbon group) are bonded on average to 1 Si atom. The M unit represents the group represented by (R) ₃ SiO _1/2 Represented as monofunctional organo siloxy units. T unit is represented by RSiO _3/2 (R represents a hydrogen atom or an organic group).

(preparation of curable composition 1)

Curable silicone (20 g), zirconium octoate compound ("Organix ZC-200", manufactured by Song Kogyo Co., ltd.) (0.16 g), cerium (III) 2-ethylhexanoate (manufactured by Alfa Aesar Co., ltd.) (metal content 12%) (0.17 g), and IsoperG (manufactured by Tokyo general Petroleum Co., ltd.) (19.7 g) as a solvent were mixed, and the resultant mixture was filtered using a filter having a pore size of 0.45 μm, thereby obtaining curable composition 1.

(preparation of curable Silicone 2)

The curable silicone 2 is obtained by mixing organohydrogensiloxane and alkenyl group-containing siloxane. In the composition of the curable silicone 2, the molar ratio of M unit, D unit, T unit was 9:59:32, the molar ratio of methyl to phenyl of the organic group is 44:56, the molar ratio of all alkenyl groups to hydrogen atoms bonded to all silicon atoms (hydrogen atoms/alkenyl groups) was 0.7, and the average number of OX groups was 0.1.

(preparation of curable composition 2)

Platinum (0) -1, 3-divinyl-1, 3-tetramethyldisiloxane (CAS No. 68478-92-2) was added to the curable silicone 2 in such a manner that the content of the platinum element was 120ppm, thereby obtaining a mixture A. Diethylene glycol diethyl ether ("Hysorb EDE", manufactured by Toho chemical industries, inc.) (84.7 g) was mixed with the mixture A (200 g), and the resultant mixture was filtered using a filter having a pore size of 0.45 μm, thereby obtaining a curable composition 2.

< example 1 >

(production of a laminate substrate comprising a glass substrate and a polysiloxane resin layer)

A PET film (manufactured by Toyo-yo Co., ltd., cosmo Shine A4160, thickness 50 μm) was prepared as a release film (corresponding to a temporary support). The film had a flat surface and an uneven surface, and the prepared curable composition 1 was coated on the flat surface side, and heated at 140 ℃ for 10 minutes using a hot plate, thereby forming a silicone resin layer.

Subsequently, a laminate in which a glass substrate, a silicone resin layer and a PET film were sequentially disposed was produced by bonding a glass substrate "AN100" (glass substrate) having a thickness of 0.5mm, which was washed with AN aqueous glass cleaner (product of k PARKER CORPORATION, PK-LCG 213) and then washed with pure water, to a PET film (size: 190mm×190 mm) having a silicone resin layer formed thereon.

Next, the obtained laminate was placed in an autoclave, and heated at 60℃under 1MPa for 30 minutes. Then, the PET film was peeled off, and the obtained laminate was put into an oven preheated to 250 ℃ and subjected to annealing treatment for 30 minutes, thereby producing a laminate substrate including a glass base material and a silicone resin layer (annealing step).

The film thickness of the polysiloxane resin layer after the annealing treatment was measured at any 10 points by a film thickness measuring system (manufactured by Filmetrics Co., "F20"). As the measurement range, a peripheral region extending 3mm from the peripheral end portion to the central portion of the silicone resin layer was excluded. The average value of the film thicknesses of the 10 measured values was 7.2. Mu.m. The maximum value of the film thickness of the silicone resin layer was 7.4. Mu.m, and the minimum value was 7.1. Mu.m. The difference between the maximum value and the minimum value of the film thickness was used as the film thickness variation. The film thickness variation was 0.3. Mu.m.

The surface roughness (Ra) of the annealed polysiloxane resin layer at any 10 points was measured using a non-contact surface, layer cross-sectional shape measuring system (manufactured by rhombic systems Co., ltd., "Vertscan R3300-lite"). As the measurement range, a peripheral region extending 3mm from the peripheral end portion to the central portion of the silicone resin layer was excluded. One measurement area was set to 940 μm long by 700 μm wide. The average value of the surface roughness of 10 measured values was 0.81nm. The maximum value of the surface roughness was 0.87nm, and the minimum value was 0.72nm. The difference between the maximum value and the minimum value of the surface roughness is referred to as the surface roughness fluctuation. The surface roughness variation was 0.15nm.

In the measurement of the film thickness and surface roughness of the silicone resin layer, when foreign matter such as lint and cullet is observed on the surface of the silicone resin layer, the measurement is performed again without using the foreign matter as measurement data.

(production of laminate)

The polysiloxane resin layer of the laminated substrate obtained above was subjected to corona treatment, and then a colorless polyimide varnish (manufactured by mitsubishi gas chemical Co., ltd., "Neopulim H230") was applied thereto, followed by heating at 80℃for 20 minutes using a hot plate. Then, the laminate was heated at 400℃for 30 minutes using an inert gas oven under a nitrogen atmosphere, to thereby obtain a laminate having a glass substrate, a silicone resin layer and a colorless polyimide film (thickness: 7 μm) in this order.

(formation of gas barrier film and Heat resistance test)

A silicon nitride film (SiN film) having a thickness of 50nm was formed on the colorless polyimide film surface of the laminate obtained in the above-described (laminate production) using a plasma CVD apparatus. Next, the laminate having the glass substrate, the silicone resin layer, the colorless polyimide film, and the silicon nitride film in this order was heated for 1 hour under a nitrogen atmosphere at 400 ℃ using an inert gas oven (heat resistance test).

(stripping of colorless polyimide film)

The colorless polyimide film having the SiN film formed on the surface was peeled from the laminate by pinching the end of the colorless polyimide film of the laminate after the heat resistance test with a finger and lifting vertically.

< examples 2 to 6, examples 9 to 13 >, respectively

Evaluation samples were prepared in the same manner as in example 1, except that the curable compositions, release films and annealing conditions shown in table 1 were used.

< example 7 >

Curable composition 1 was applied onto a glass substrate "AN100" (glass substrate) of 190mm by 190mm in thickness and 0.5mm in thickness, which was washed with AN aqueous glass cleaner (Kyowa Co., ltd. PARKER CORPORATION, "PK-LCG 213") and then washed with pure water, using a spin coater. The polysiloxane resin layer was formed by heating at 140℃for 10 minutes using a hot plate. The laminated substrate including the glass base material and the silicone resin layer was put into an oven preheated to 250 c, and subjected to an annealing treatment for 30 minutes (annealing step).

The film thickness at any 10 points of the annealed silicone resin layer was measured by a film thickness measuring system (manufactured by Filmetrics Co., ltd., "F20") (excluding a peripheral region extending 3mm from the end portions to the central portion of the silicone resin layer as a measurement range). The average value of the film thicknesses of the 10 measured values was 7.0. Mu.m. The maximum value of the film thickness was 9.5. Mu.m, and the minimum value was 6.8. Mu.m. The film thickness variation, which is the difference between the maximum value and the minimum value of the film thickness, was 2.7. Mu.m.

The surface roughness (Ra) of the annealed polysiloxane resin layer at any 10 points was measured using a non-contact surface/layer cross-sectional shape measurement system (manufactured by rhombic systems Co., ltd., "Vertscan R3300-lite"). As the measurement range, a peripheral region extending 3mm from the end portions to the central portion of the silicone resin layer was excluded. One measurement area was set to 940. Mu.m.times.700. Mu.m. The average value of the surface roughness of 10 measured values was 0.42nm. The maximum value of the surface roughness was 0.47nm, and the minimum value was 0.40nm. The surface roughness variation, which is the difference between the maximum value and the minimum value of the surface roughness, was 0.07nm.

In the measurement of the film thickness and surface roughness of the silicone resin layer, when foreign matter such as lint and cullet is observed on the surface of the silicone resin layer, the measurement is performed again without being adopted as measurement data.

(production of laminate)

The polysiloxane resin layer of the laminated substrate obtained above was subjected to corona treatment, and then a colorless polyimide varnish (manufactured by mitsubishi gas chemical Co., ltd., "Neopulim H230") was applied thereto, followed by heating at 80℃for 20 minutes using a hot plate. Then, the laminate was heated at 400℃for 30 minutes using an inert gas oven under a nitrogen atmosphere (curing step), thereby obtaining a laminate having a glass substrate, a silicone resin layer and a colorless polyimide film (thickness: 7 μm) in this order.

(formation of gas barrier film and Heat resistance test)

A silicon nitride film (SiN film) having a thickness of 50nm was formed as a gas barrier film on the colorless polyimide film surface of the laminate obtained above (laminate production) using a plasma CVD apparatus.

Next, as a heat resistance test, a laminate having a glass substrate, a silicone resin layer, a colorless polyimide film, and a silicon nitride film in this order was heated for 1 hour at 400 ℃ in a nitrogen atmosphere using an inert gas oven.

(stripping of colorless polyimide film)

The colorless polyimide film (with SiN film on the surface) was peeled from the laminate by pinching the end of the colorless polyimide film of the laminate after the heat resistance test with a finger and lifting vertically.

< example 8, example 14, example 15 >

Evaluation samples were prepared in the same manner as in example 7, except that the curable compositions, the method for forming a silicone resin layer, and the annealing conditions shown in table 1 were used.

< evaluation of unevenness of colorless polyimide film >

The colorless polyimide film after peeling was visually observed, and the optical unevenness (unevenness) of the colorless polyimide film was evaluated. The evaluation area was set to 184mm×184mm, and evaluation was performed according to the following evaluation criteria.

And (3) the following materials: no unevenness was observed over the whole surface

And (2) the following steps: unevenness was observed in the region of less than 10% of the evaluation area

X: unevenness was observed in a region of 10% or more of the evaluation area

The results of the unevenness evaluation are shown in table 2.

In table 2, the "average" column of the "film thickness [ μm ]" column indicates the arithmetic average value of the measured values of 10 film thicknesses of the silicone resin layer, the "maximum" column indicates the maximum value of the measured values of 10 film thicknesses, the "minimum" column indicates the minimum value of the measured values of 10 film thicknesses, and the "fluctuation" column indicates the difference between the maximum value and the minimum value.

In table 2, the "average" column of the "surface roughness Ra [ nm ] column of the silicone resin layer indicates an arithmetic average value of the 10 measured values of the surface roughness of the silicone resin layer, the" maximum "column indicates a maximum value of the 10 measured values of the surface roughness, the" minimum "column indicates a minimum value of the 10 measured values of the surface roughness, and the" fluctuation "column indicates a difference between the maximum value and the minimum value.

TABLE 1

TABLE 2

As is clear from comparison of examples 1 to 4, 9 and 10 with examples 5, 6 and 11 to 13, colorless polyimide films having less optical unevenness (unevenness) can be obtained if the surface roughness Ra of the polysiloxane resin layer varies by 1.00nm or less.

From comparison of examples 1 to 4, 9 and 10 with examples 7, 8, 14 and 15, it is found that colorless polyimide films having less optical unevenness (unevenness) can be obtained if the film thickness of the polysiloxane resin layer varies by 1.5 μm or less.

Further, it was confirmed from the comparison of examples 1 to 4 with examples 9 and 10 that the effect was more excellent when the variation of the surface roughness Ra was 0.40nm or less.

< manufacturing of organic EL display device (corresponding to electronic device) >)

The following procedure was followed using the laminate obtained in examples 1 to 4, 9, and 10 to produce an organic EL display device.

First, a silicon nitride film, a silicon oxide film, and an amorphous silicon film are sequentially formed on a surface of a polyimide film of a laminated substrate on the side opposite to the glass substrate side by a plasma CVD method. Then, boron with a low concentration is implanted into the amorphous silicon layer by an ion doping apparatus, and a heating treatment and a dehydrogenation treatment are performed. Next, crystallization treatment of the amorphous silicon layer is performed by a laser annealing device. Next, phosphorus of low concentration is implanted into the amorphous silicon layer by using an etching and ion doping apparatus using photolithography, thereby forming N-type and P-type TFT regions.

Next, a silicon oxide film was formed on the side of the polyimide film opposite to the glass substrate side by a plasma CVD method to form a gate insulating film, and then molybdenum was formed by a sputtering method to form a gate electrode by etching using a photolithography method. Next, boron and phosphorus are implanted in high concentrations into the respective desired regions of the N-type and P-type by photolithography and an ion doping apparatus, thereby forming a source region and a drain region.

Next, an interlayer insulating film was formed by forming a silicon oxide film on the side of the polyimide film opposite to the glass substrate side by a plasma CVD method, and an aluminum film was formed by a sputtering method and a TFT electrode was formed by etching using a photolithography method. Next, a passivation layer is formed by performing a heat treatment in a hydrogen atmosphere, a hydrogenation treatment, and then forming a silicon nitride film by a plasma CVD method.

Next, an ultraviolet curable resin was applied to the polyimide film on the side opposite to the glass substrate side, and a planarizing layer and a contact hole were formed by photolithography. Next, indium tin oxide was formed into a film by a sputtering method, and a pixel electrode was formed by etching using a photolithography method. Next, a polyimide film was deposited by vapor deposition The opposite side of the glass substrate is formed in sequence: 4,4' -tris (3-methylphenyl phenylamino) triphenylamine film as hole injection layer and bis [ (N-naphthyl) -N-phenyl film as hole transport layer]Benzidine film, 8-hydroxyquinoline aluminum complex (Alq) as light-emitting layer ₃ ) Is mixed with 40% by volume of 2, 6-bis [4- [ N- (4-methoxyphenyl) -N-phenyl ]]Aminostyryl group]Film of mixture of naphthalene-1, 5-dimethylnitrile (BSN-BCN), alq as electron transport layer ₃ And (3) a film. Next, aluminum was formed into a film by a sputtering method, and a counter electrode was formed by etching using a photolithography method.

Next, another glass substrate was bonded to the polyimide film on the side opposite to the glass substrate side via an ultraviolet-curable adhesive layer, and sealed. Through the above-described operation steps, an organic EL structure is formed on the polyimide film. The structure having an organic EL structure on a polyimide film (hereinafter referred to as a panel a) is a laminate with a member for an electronic device.

Next, the sealing body side of the panel a was vacuum-sucked onto the stage, and then a stainless steel cutter having a thickness of 0.1mm was inserted into the interface between the polyimide film and the glass substrate at the corner of the panel a, and the peeling start was formed at the interface between the polyimide film and the glass substrate. Then, the glass substrate surface of the panel a was sucked by using a vacuum chuck, and then the chuck was lifted. Here, the insertion of the cutter is performed while blowing the electric fluid from the ionizer (manufactured by kenshi corporation) to the interface.

Then, the vacuum chuck is pulled while continuing to blow off the electrical fluid from the ionizer to the formed void and while injecting water to the peeling front. As a result, only the polyimide film having the organic EL structure formed thereon remains on the stage, and the glass substrate having the polysiloxane resin layer can be peeled off.

Next, the separated polyimide film is cut into a plurality of units by a laser cutter or a scribe-and-break method, and then the polyimide film having the organic EL structure formed thereon is assembled with a counter substrate, and a module forming process is performed, thereby manufacturing an organic EL display device.

While various embodiments have been described above with reference to the drawings, the present invention is not limited to this example. It is obvious that various modifications and corrections can be made by those skilled in the art within the scope of the claims, and these naturally fall within the scope of the present invention. The components of the above embodiments may be arbitrarily combined within a range not departing from the gist of the invention.

The present application is based on japanese patent application (japanese patent application publication No. 2021-072745) filed at 22, 4, 2021, the contents of which are incorporated herein by reference.

Description of the reference numerals

10. Laminated substrate

12. Glass substrate

14. Polysiloxane resin layer

16. Laminate body

18. Polyimide film

20. Member for electronic device

22. Laminate with component for electronic device

24. Electronic device

26. Glass substrate with polysiloxane resin layer

Claims

1. A laminated substrate, the laminated substrate comprising:

the film thickness of the polysiloxane resin layer varies by 1.5 μm or less.

2. The laminated substrate according to claim 1, wherein the average value of the film thickness of the silicone resin layer is 50.0 μm or less.

3. The laminated substrate according to claim 1 or 2, wherein a releasable protective film is provided on the polysiloxane resin layer.

4. A laminate, wherein the laminate has the laminate substrate according to claim 1 or 2 and a polyimide film disposed on the polysiloxane resin layer of the laminate substrate.

5. A method for producing a laminate, wherein a polyimide varnish comprising polyimide or a precursor thereof and a solvent is coated on the polysiloxane resin layer of the laminated substrate according to claim 1 or 2 to form a polyimide film on the polysiloxane resin layer, thereby forming a laminate having the glass substrate, the polysiloxane resin layer and the polyimide film.

6. A laminate with a member for an electronic device, wherein the laminate with a member for an electronic device has:

the laminate according to claim 4, and

and an electronic device member disposed on the polyimide film in the laminate.

7. A method of manufacturing an electronic device, wherein the method of manufacturing an electronic device comprises:

a member forming step of forming a member for an electronic device on the polyimide film of the laminate of claim 4, thereby obtaining a laminate with a member for an electronic device; and