JP6718736B2 - Method for peeling heat-resistant organic polymer layer and method for manufacturing flexible wiring board - Google Patents

Description

The present invention relates to a method for peeling a heat-resistant organic polymer layer from a substrate, for example, manufacturing a flexible device or a flexible wiring board in which an electronic element is formed on the surface of a heat-resistant organic polymer layer (for example, a polyimide film). It is useful when doing.

2. Description of the Related Art Conventionally, in the field of flat panel displays (FPD) such as liquid crystal displays (LCD), plasma display panels (PDP), organic EL displays (OLED) and electronic devices such as electronic paper, electronic elements are mainly formed on a glass substrate. Things are used. However, since the glass substrate is rigid and lacks flexibility, it is difficult to be flexible.

Therefore, a method of using a heat-resistant organic polymer material such as polyimide having flexibility and heat resistance as a substrate is known. For example, a flexible heat-resistant polyimide coating film is formed on a glass substrate with excellent light-transmitting properties for a carrier, and this coating film is used as a substrate for forming electronic elements or a wiring substrate. The method to do is proposed.

In the glass substrate on which such a polyimide coating film is formed, the glass substrate is used as a carrier substrate. Therefore, after forming an electronic element on the surface of the polyimide coating film, a method of peeling the polyimide film from the glass substrate by irradiating the polyimide interface in contact with the glass substrate with a laser is disclosed (Patent Documents 1 and 2). ). However, this method has a problem that it is difficult to cope with an increase in the size of equipment and that the laser processing requires a long time.

Therefore, a peeling method that does not use a laser has been proposed. For example, Patent Documents 3 and 4 propose methods of using light rays from a xenon flash lamp or the like. In this method, a photothermal conversion film such as a molybdenum thin film or a silicon thin film is provided on the surface of a glass substrate, and an organic polymer layer is provided on this surface to form a laminated body. Is irradiated with light from a xenon flash lamp or the like to peel off the organic polymer layer on the photothermal conversion layer.

JP, 2006-203219, A Japanese Patent Publication No. 2007-512568 JP, 2013-235196, A JP, 2013-145808, A

However, the methods described in Patent Documents 3 and 4 are not always sufficient in releasability. Further, it is difficult to repeatedly use the glass substrate having the photothermal conversion layer formed thereon.

Therefore, the present invention is to solve the above problems, and an object thereof is to provide a method for easily and sufficiently peeling a heat resistant organic polymer layer from a substrate such as a glass substrate without using a laser. ..

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and after arranging a specific structure of a laminate composed of a substrate and a heat-resistant organic polymer layer, irradiating with a specific light beam The inventors have found that the problems can be solved and completed the present invention.

That is, the present invention has the following gist.
A laminate having at least one heat-resistant organic polymer layer formed on a substrate is irradiated with a continuous light beam in a wide wavelength range to separate at the interface between the substrate and the heat-resistant organic polymer layer. A method for peeling a heat-resistant organic polymer layer, which comprises:
A peeling method, wherein a heat-resistant organic polymer layer A containing a filler having a photothermal conversion ability is formed in contact with the substrate in the laminate.

The present invention also provides a laminate obtained by forming a heat-resistant organic polymer layer A containing a filler having a photothermal conversion ability, a heat-resistant organic polymer layer B not containing the filler, and an electronic element in this order on a substrate. On the other hand, the present invention also relates to a method for manufacturing a flexible wiring board, which is characterized by applying the above-mentioned peeling method.

According to the peeling method of the present invention, the heat resistant organic polymer layer can be easily and sufficiently peeled from the substrate without using a laser. Therefore, the peeling method of the present invention is useful for manufacturing flexible devices and flexible wiring boards. The substrate from which the heat-resistant organic polymer layer is peeled off can be used repeatedly.

Hereinafter, the present invention will be described in detail.

The present invention relates to a method for peeling a heat resistant organic polymer layer laminated on a substrate. Specifically, peeling is performed at the interface between the substrate and the heat resistant organic polymer layer.

A glass substrate, a single crystal substrate, or a polycrystalline substrate can be used as the substrate. As the glass substrate, for example, a substrate made of soda lime glass, borosilicate glass, non-alkali glass, or the like can be used. Among these, non-alkali glass substrate is preferable, and quartz glass may be used. These glass substrates may be subjected to a known surface treatment such as a silane coupling agent treatment. As the single crystal substrate, for example, a substrate made of quartz, sapphire, or the like can be used, and as the polycrystalline substrate, a substrate in which these are polycrystalline can be used. Generally, the substrate only needs to transmit a light ray in at least a part of the irradiated wavelength range, and preferably has a transparency to a wavelength in the near infrared range.

The thickness of the substrate is preferably 0.3 to 5.0 mm, and particularly preferably 0.3 to 3.0 mm, from the viewpoints of handleability and productivity of the substrate.

The heat-resistant organic polymer layer laminated on the substrate contains at least one heat-resistant organic polymer layer, and contains a filler having a photothermal conversion ability as the heat-resistant organic polymer layer in contact with the substrate. A heat-resistant organic polymer layer (herein, referred to as "heat-resistant organic polymer layer A") is included. Any heat-resistant organic polymer layer may be formed on the surface of the heat-resistant organic polymer layer A laminated on the substrate.

From the viewpoint of applying the peeling method of the present invention to the method for manufacturing a flexible wiring board, the heat-resistant organic polymer layer laminated on the substrate is heat-resistant not containing at least the heat-resistant organic polymer layer A and a filler having a photothermal conversion ability. It is preferable to include an organic polymer layer (referred to as “heat resistant organic polymer layer B” in this specification) in this order from the substrate side, and an electronic element such as wiring is formed on the surface of the heat resistant organic polymer layer B. Is more preferable.

In the present invention, the heat-resistant organic polymer layer A formed so as to be in direct contact with the substrate contains a heat-resistant organic polymer and a filler having a photothermal conversion ability.

The heat resistant organic polymer used in the method of the present invention means an organic polymer having a glass transition temperature (Tg) of 250° C. or higher measured by DSC (differential thermal analysis). Specific examples of the heat resistant organic polymer include polyimide, modified polyimide (polyamideimide, polyesterimide, etc.), polybenzimidazole, polybenzoxazole, aramid and the like. Of these, polyimide is preferred.

As the polyimide, it is preferable to use a polyimide obtained by thermosetting a polyamic acid (hereinafter, may be abbreviated as “PAA”) that is a precursor thereof. PAA is obtained by reacting tetracarboxylic dianhydride and diamine, which are raw materials, in approximately equimolar amounts in a solvent.

Examples of the tetracarboxylic dianhydride include pyromellitic acid, 3,3′,4,4′-biphenyltetracarboxylic acid, 3,3′,4,4′-benzophenonetetracarboxylic acid and 3,3′. ,4,4'-diphenylsulfone tetracarboxylic acid, acid, 3,3',4,4'-diphenyl ether tetracarboxylic acid, 2,3,3',4'-benzophenone tetracarboxylic acid, 2,3,6,7 -Naphthalene tetracarboxylic acid, 1,4,5,7-naphthalene tetracarboxylic acid, 1,2,5,6-naphthalene tetracarboxylic acid, 3,3',4,4'-diphenylmethane tetracarboxylic acid, 2,2 -Bis(3,4-dicarboxyphenyl)propane, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane, 3,4,9,10-tetracarboxyperylene, 2,2-bis[4 -(3,4-dicarboxyphenoxy)phenyl]propane, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]hexafluoropropane, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,4,5-Cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetra Examples include dianhydrides of carboxylic acids. Of these, pyromellitic dianhydride (PMDA) and 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) are preferable. These tetracarboxylic dianhydrides can be used alone or as a mixture of two or more kinds.

Examples of the diamine include p-phenylenediamine (PDA), m-phenylenediamine, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether (DADE), 4,4′-diaminodiphenylmethane, 3,3. '-Dimethyl-4,4'-diaminodiphenylmethane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 1,2-bis(anilino)ethane, diaminodiphenyl sulfone, diaminobenzanilide, diaminobenzoate , Diaminodiphenyl sulfide, 2,2-bis(p-aminophenyl)propane, 2,2-bis(p-aminophenyl)hexafluoropropane, 1,5-diaminonaphthalene, diaminotoluene, diaminobenzotrifluoride, 1, 4-bis(p-aminophenoxy)benzene, 4,4′-bis(p-aminophenoxy)biphenyl, diaminoanthraquinone, 4,4′-bis(3-aminophenoxyphenyl)diphenylsulfone, and the like, including PDA and DADE is preferred. These diamines can be used alone or as a mixture of two or more kinds.

The filler having a photothermal varying換能contained in heat-resistant organic polymer layer A, by absorbing light having a wavelength in the near infrared region, refers to filler which itself generates heat. The type of filler is not limited, and specifically, carbon particles (graphite, carbon black, carbon nanotubes, carbon nanosheets, graphene, diamond-like carbon, etc.), metal oxide particles (iron oxide, nickel oxide, copper oxide, etc.) ), a metal (titanium, aluminum, molybdenum, etc.), a silicon particle, an organic pigment (atine-based, phthalocyanine-based, etc.) and the like. Among these, carbon particles and silicon particles are preferable. Filler having a photothermal varying換能may be used alone or as a mixture of two or more thereof.

Whether or not the used filler has a photothermal conversion ability can also be determined by the following method.
Photothermal strange換能of determination method:
First, a heat-resistant organic polymer film having a thickness of about 30 μm containing 30% by mass of filler is formed on a substrate. This is determined by irradiating a light beam from a xenon flash lamp from the substrate side and comparing the adhesive strength between the filler-containing heat-resistant organic polymer film and the substrate before and after the irradiation. If the adhesive strength after irradiation is 50% or more lower than the adhesive strength before irradiation, the filler is judged to have a photothermal conversion ability. On the contrary, if the decrease rate of the adhesive strength after irradiation is less than 50%, it is determined that the filler has no photothermal conversion ability. Here, the irradiation conditions of the light rays are the same as the irradiation conditions adopted in Example 1 of the present application. As the adhesive strength, a value measured by performing a 180° peel test based on JIS K6854-2 is used.

The average particle size range of the filler having photothermal conversion ability is preferably about 0.01 to 2 μm, more preferably 0.02 to 1 μm, and further preferably 0.02 to 0.5 μm. .. Here, the average particle size refers to a volume-based measurement value measured by a laser diffraction method. The particle shape is not limited, such as an irregular shape, a spherical shape, a square shape, and a linear shape, but an irregular shape is preferable. The content of such filler is preferably 5 to 50% by mass, more preferably 10 to 40% by mass, based on the total mass of the heat resistant organic polymer layer A.

The thickness of the heat resistant organic polymer layer A is preferably 0.1 to 5 μm, more preferably 0.2 to 4 μm, and further preferably 0.5 to 4 μm.

The heat resistant organic polymer layer B is preferably formed on the surface of the heat resistant organic polymer layer A. The heat-resistant organic polymer layer B contains the heat-resistant organic polymer, but does not contain the filler having the photothermal conversion ability as described above. The heat-resistant organic polymer layer B contains no filler having a photothermal varying換能, the content of filler with the photothermal variable換能is, relative to the total weight of the heat-resistant organic polymer layer B, 5 wt% It is less than. The heat-resistant organic polymer layer B, known additives used in the normal polyimide film production (e.g., lubricants, etc.) also filler having no photothermal varying換能of Examples are contained in any amount Good.

The heat-resistant organic polymer contained in the heat-resistant organic polymer layer B is independent of the heat-resistant organic polymer layer A within the same range as the heat-resistant organic polymer contained in the heat-resistant organic polymer layer A. However, polyimide is preferred. The polyimide in the heat resistant organic polymer layer B may be the polyimide exemplified in the description of the heat resistant organic polymer layer A, and the same polyimide as the preferable polyimide exemplified in the description of the heat resistant organic polymer layer A is preferable.

The heat-resistant organic polymer layer B preferably has a thickness of about 5 to 100 μm.

The laminate used in the present invention comprises at least a heat resistant organic polymer layer A formed on a substrate, preferably at least a heat resistant organic polymer layer A and a heat resistant organic polymer layer B on the substrate. Are formed in this order. Such preferred laminate, for example, on a substrate, the light-to-heat strange換能uniformly mixed and heat-resistant organic polymer layer A forming PAA solution filler having a (hereinafter, abbreviated as "PAA-1 ' Is applied and dried, and then the surface of the coating film is coated with a PAA solution for forming a heat-resistant organic polymer layer B containing no filler (hereinafter, may be abbreviated as “PAA-2”), After drying, PAA is obtained by thermosetting. In addition, known additives such as various surfactants and organic silane coupling agents may be added to these PAA solutions, if necessary, within a range that does not impair the effects of the present invention.

The PAA solution is obtained, for example, by polymerizing approximately equimolar amounts of tetracarboxylic dianhydride and aromatic diamine in a solvent. The solvent used is not limited as long as it is a solvent that dissolves PAA. For example, an amide solvent, a urea solvent, an ether solvent, or the like can be used.

Specific examples of the amide solvent include N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc) and the like. Further, specific examples of the urea-based solvent include tetramethylurea, tetraethylurea, dimethylethyleneurea, dimethylpropyleneurea and the like. Further, specific examples of the ether-based solvent include 2-methoxyethanol, 2-ethoxyethanol, 2-(methoxymethoxy)ethoxyethanol, 2-isopropoxyethanol, 2-butoxyethanol, tetrahydrofurfuryl alcohol, diethylene glycol, diethylene glycol monomethyl. Ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monoethyl ether, tetraethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether Examples thereof include ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, polyethylene glycol, polypropylene glycol, tetrahydrofuran, dioxane, 1,2-dimethoxyethane, diethylene glycol dimethyl ether and diethylene glycol diethyl ether. These solvents can be used alone or in combination of two or more. Of these, NMP and DMAc are preferred.

As a reaction temperature at the time of producing a PAA solution, −30 to 70° C. is preferable, and −15 to 50° C. is more preferable. In addition, in this reaction, the order of addition of the monomer and the solvent is not particularly limited and may be any order. The solid content concentration of the PAA solution is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. This PAA may be partially imidized. In the present invention, the viscosity of the PAA solution at 25°C is preferably 0.05 to 150 Pa·s, more preferably 0.1 to 100 Pa·s. The viscosity may be adjusted by known means such as diluting appropriately according to the coating method. Commercially available products can be used as these PAA solutions.

To produce the preferred laminate in the present invention, specifically, first, PAA-1 is applied onto a substrate and dried. Next, PAA-2 is applied onto this coating film, dried, and then heat cured collectively. The drying temperature after coating is preferably 80 to 200°C, and more preferably 80 to 150°C for both PAA-1 and PAA-2. The thermosetting temperature is preferably 350 to 520°C, more preferably 350 to 450°C, further preferably 380 to 450°C, and further preferably 380 to 420°C. preferable. Note that it is preferable to apply PAA-2 without thermally curing after applying and drying PAA-1 as described above. By doing so, the adhesive strength at the interface between the heat resistant organic polymer layer A and the heat resistant organic polymer layer B is improved, and a strongly integrated heat resistant organic polymer film can be obtained. ..

As a method for applying PAA-1 to the substrate and a method for applying PAA-2 to the PAA-1 coating film, known methods such as a dip coater, a bar coater, a spin coater, a die coater, and a spray coater are used, and a continuous method or a batch method is used. Can be applied with.

In the present invention, the heat-resistant organic polymer layer A of the laminate obtained as described above is irradiated with a continuous light beam in a wide wavelength range from a light source, so that the heat-resistant organic polymer layer can be easily and sufficiently heated. The molecular layer A can be peeled off from the substrate. As the substrate, it is preferable to use a substrate that is transmissive to light in at least the near infrared region, and more desirably, the wavelength region absorbed by the filler. The light rays are preferably emitted from the substrate side. After the irradiation, the substrate is completely separated from the laminate by a known method, for example, a method using a mechanical device such as a driving roll or a robot or a manual method. Here, peeling occurs only at the interface between the heat resistant organic polymer layer A and the substrate. For filler having a photothermal varying換能contained in the heat-resistant organic polymer layer A is absorbed rapidly heating the light, rapid temperature of the heat-resistant organic polymer constituting the heat-resistant organic polymer layer A Rises and expands. Therefore, it is considered that the adhesive strength at the interface between the heat-resistant organic polymer layer A and the substrate is significantly reduced and the heat-resistant organic polymer layer is easily peeled off. In the present invention, the heat-resistant organic polymer layer A containing a filler having a light-heat converting ability is not irradiated with light, but the film composed of the light-heat converting substance itself such as a silicon thin film is irradiated with light. Therefore, since relatively large expansion can be caused, it is considered that the heat resistant organic polymer layer A can be easily and sufficiently peeled off.

Irradiating a continuous light beam in a wide wavelength range means irradiating a continuous light beam in a relatively wide wavelength range, unlike a laser having a single wavelength. Wavelength region of light to be irradiated may if it contains a wavelength range of filler having a photothermal varying換能that at least the can absorb, typically includes wavelength range of the near-infrared region. A preferred wavelength range includes a continuous wavelength spectral range from ultraviolet to infrared.

A flash lamp is preferably used as a light source for irradiating such light rays. Specific examples of flash lamps include xenon lamps and halogen lamps. Among these, a xenon flash lamp having a continuous spectrum from ultraviolet to infrared, capable of instantaneously obtaining a large amount of light, and capable of high-speed repetitive light emission is preferable.

Irradiation conditions are not particularly limited as long as peeling between the substrate and the heat resistant organic polymer layer A is achieved. For example, an irradiation time (pulse width) of about 0.05 ms or more and about 100 ms or less, and an irradiation energy of about 1 J/cm ² or more and about 20 J/cm ² or less, which is extremely short and strong, may be used. Further, as long as peeling between the substrate and the heat resistant organic polymer layer A is achieved, the flash lamp may be irradiated once or plural times. The reason why the preferable irradiation energy has a lower limit is that the temperature of the interface between the heat-resistant organic polymer layer A and the substrate cannot be sufficiently increased. Therefore, at the interface between the substrate and the heat-resistant organic polymer layer A, if the adhesive force at the interface is sufficiently reduced, the irradiation energy may be lower than 1 J/cm ^2. .. The reason why the preferable irradiation energy has an upper limit is that the substrate and the heat-resistant organic polymer layer A can be separated to such an extent that the substrate and the heat-resistant organic polymer layer A can be separated by applying the irradiation energy at the upper limit. At the interface of, the point that the adhesive force of the interface is reduced and it is not necessary to give the irradiation energy above the upper limit, and the increase of power consumption of the xenon flash lamp is suppressed by not outputting the extra irradiation energy, The point is that it contributes to a longer life, and that the device mounted on the heat-resistant organic polymer layer A is prevented from being damaged by not giving extra irradiation energy to the heat-resistant organic polymer layer A. To be Therefore, when the irradiation energy satisfying the above points is higher than 20 J/cm ² due to various conditions such as the thickness and composition of the heat-resistant organic polymer layer A and the characteristics of the material used as the substrate, 20 J/cm 2 Irradiation energy of ² or more is also adopted as a suitable condition.

As described above, according to the peeling method of the present invention, the heat resistant organic polymer layer can be easily and sufficiently peeled from the substrate without using a laser.

The heat-resistant organic polymer layer peeling method of the present invention is useful for manufacturing a flexible wiring board. Specifically, in the above-mentioned laminate formed by forming a heat-resistant organic polymer layer A and a heat-resistant organic polymer layer B on a substrate in this order, the surface of the heat-resistant organic polymer layer B is provided with electrons such as desired wirings. The element is formed in advance. Since an electric element, particularly an organic EL, is easily deteriorated by moisture, a gas barrier film can be formed on the heat-resistant organic layer B before forming the electric element, if necessary. By applying the above peeling method to this laminate, peeling occurs at the interface between the substrate and the heat-resistant organic polymer layer A, and the flexible wiring board can be easily manufactured.

Hereinafter, the present invention will be specifically described based on Examples, but the present invention is not limited to these Examples.

<Preparation of polyimide precursor solution>
PAA (polyimide precursor) solutions used in Examples and Comparative Examples were prepared as follows.

<Preparation of filler-free polyimide precursor solution PAA-2>
In a nitrogen atmosphere, PDA (0.6 mol) and dehydrated DMAc (polymerization solvent) were placed in a glass reaction vessel and stirred to dissolve PDA. While cooling this solution to 30° C. or lower with a jacket, BPDA (0.6 mol) was gradually added, and then a polymerization reaction was carried out at 50° C. for 100 minutes to obtain a polyimide precursor solution PAA-2. The solid content concentration of PAA-2 was 15% by mass, and the polystyrene-equivalent weight average molecular weight (Mw) by gel permeation chromatography (GPC) was 62,000.

<Preparation of filler-containing polyimide precursor solution PAA-1>
(PAA-1-1)
Carbon black (average particle size: 0.03 μm, CTE: 3.0 ppm/° C.) and dehydrated DMAc (diluting solvent) were added to PAA-2, and a mixing treatment was performed for 60 minutes using a planetary mixer to obtain a solid content. Was 16% by mass and the carbon black content was 30% by mass with respect to the total solid content to obtain a filler-containing polyimide precursor solution PAA-1-1.

(PAA-1-2)
PAA-1-2 was obtained by the same method as the production method of PAA-1-1 except that the carbon black content was 50% by mass with respect to the total solid content.

(PAA-1-3)
PAA-1-3 was obtained by the same method as the production method of PAA-1-1 except that the carbon black content was 10% by mass with respect to the total solid content.

(PAA-1-4)
PAA-1-4 was obtained by the same method as the production method of PAA-1-1 except that graphite particles (average particle diameter: 0.3 μm, CTE: 3.2 ppm/° C.) were used as fillers. ..

(PAA-1-5)
PAA-1-5 was obtained by the same method as the method for producing PAA-1-4, except that the content of graphite particles was 10% by mass with respect to the total solid content.

(PAA-1-6)
PAA-1-6 was obtained by the same method as the method for producing PAA-1-1 except that silicon particles (average particle diameter: 0.5 μm, CTE: 4.7 ppm/° C.) were used as fillers. ..

(PAA-1-7)
PAA-1-7 was obtained by the same method as the production method of PAA-1-1 except that silicon dioxide particles (average particle diameter: 0.5 μm, CTE: 0.5 ppm/° C.) were used as fillers. It was

(PAA-1-8)
PAA-1-8 was obtained by the same method as the method for producing PAA-1-1 except that glass particles (average particle diameter: 1 μm, CTE: 4.0 ppm/° C.) were used as fillers.

[Example 1]
PAA-1-1 was applied on a 0.7 mm-thick non-alkali glass substrate (Eagle 2000 manufactured by Corning Co., Ltd.) by a table coater and dried at 130° C. for 10 minutes to form a PAA film. Then, the temperature was returned to room temperature (25° C.), PAA-2 was coated on this PAA coating by a table coater, and dried at 130° C. for 10 minutes to form a second PAA coating. Then, under a nitrogen gas stream, the temperature was raised from 100° C. to 400° C. over 2 hours and then heat-treated at 400° C. for 2 hours to thermally cure PAA to imidize it. Thus, a layered product L-1 was obtained in which Layer-1 (filler-containing polyimide layer: thickness 3 μm) and Layer-2 (filler-free polyimide layer: thickness 20 μm) were formed in this order on this glass substrate ( Polyimide coating thickness: 23 μm).

In the laminated body L-1, the peeling property before and after irradiation with a xenon flash lamp at the interface between the polyimide coating and the glass substrate was evaluated as follows. That is, the adhesive strength at the interface between the polyimide coating and the glass substrate of the unirradiated laminated body L-1 and the laminated body L-1 irradiated with the xenon flash lamp was measured by a 180° peel test based on JIS K6854, respectively. .. When the adhesive strength of the irradiated laminate was 50% or less of the adhesive strength of the non-irradiated laminate, the peeling property was determined to be “good”, and when it was more than 50%, the peeling property was determined to be “poor”. The results are shown in Table 1. Note that the xenon flash lamp irradiation has an irradiation time (pulse width) of 0.5 milliseconds or more and 1 millisecond or less and irradiation energy of 3 J/cm ² or more and 7 J/cm ² or less on the glass substrate side. It was irradiated from.

[Example 2]
By the same method as in Example 1 except that PAA-1-2 was used as the layer-1 forming solution, layer-1 (filler-containing polyimide layer: thickness 3 μm) and layer-2 (filler) were formed on the glass substrate. A laminate L-2 in which a non-containing polyimide layer: thickness 20 μm) was formed in this order was obtained (thickness of polyimide coating: 23 μm).
The peeling property of the laminate L-2 was evaluated in the same manner as in Example 1.

[Example 3]
By the same method as in Example 1 except that PAA-1-3 was used as the layer-1 forming solution, layer-1 (filler-containing polyimide layer: thickness 2 μm) and layer-2 (filler) were formed on the glass substrate. A laminate L-3 in which a non-containing polyimide layer: thickness 20 μm) was formed in this order was obtained (thickness of polyimide coating: 22 μm).
The peeling property of the laminate L-3 was evaluated in the same manner as in Example 1.

[Example 4]
By the same method as in Example 1 except that PAA-1-4 was used as the layer-1 forming solution, layer-1 (filler-containing polyimide layer: thickness 3 μm) and layer-2 (filler) were formed on the glass substrate. A laminate L-4 having a non-containing polyimide layer: thickness 20 μm formed in this order was obtained (thickness of polyimide coating: 23 μm).
The peeling property of the laminate L-4 was evaluated in the same manner as in Example 1.

[Example 5]
By the same method as in Example 1 except that PAA-1-5 was used as the layer-1 forming solution, layer-1 (filler-containing polyimide layer: thickness 2 μm) and layer-2 (filler) were formed on the glass substrate. A laminate L-5 having a non-containing polyimide layer: thickness 20 μm formed in this order was obtained (thickness of polyimide coating: 22 μm).
The peeling property of the laminate L-5 was evaluated in the same manner as in Example 1.

[Example 6]
By the same method as in Example 1 except that PAA-1-6 was used as the layer-1 forming solution, layer-1 (filler-containing polyimide layer: thickness 3 μm) and layer-2 (filler) were formed on the glass substrate. A laminate L-6 in which a non-containing polyimide layer: thickness 20 μm) was formed in this order was obtained (thickness of polyimide coating: 23 μm).
The peeling property of the laminate L-6 was evaluated in the same manner as in Example 1.

[Comparative Example 1]
Layer-1 (filler-free polyimide layer: thickness 3 μm) and layer- were formed on a glass substrate in the same manner as in Example 1 except that filler-free PAA-2 was used as the layer-1 forming solution. A laminate L-7 having 2 (filler-free polyimide layer: thickness 20 μm) formed in this order was obtained (thickness of polyimide coating: 23 μm).
The peeling property of the laminated body L-7 was evaluated in the same manner as in Example 1.

[Comparative Example 2]
By the same method as in Example 1 except that PAA-1-7 was used as the layer-1 forming solution, layer-1 (filler-containing polyimide layer: thickness 3 μm) and layer-2 (on a glass substrate). A laminate L-8 in which a filler-free polyimide layer: thickness 20 μm) was formed in this order was obtained (thickness of polyimide coating: 23 μm).
The peeling property of the laminated body L-8 was evaluated in the same manner as in Example 1.

[Comparative Example 3]
PAA-2 was coated on the surface of the alkali-free glass substrate with a table coater so that the thickness of the coating after heat curing was 23 μm, and dried at 130° C. for 10 minutes to form a PAA coating. Then, under a nitrogen gas stream, the temperature was raised from 100° C. to 400° C. over 2 hours and then heat-treated at 400° C. for 2 hours to thermally cure PAA to imidize it. Thus, a laminated body L-9 in which the filler-free polyimide was formed as a single layer on the glass substrate was obtained (thickness of polyimide coating: 23 μm).
The peeling property of the laminated body L-9 was evaluated in the same manner as in Example 1.

[Comparative Example 4]
By the same method as in Example 1 except that PAA-1-8 was used as the layer-1 forming solution, layer-1 (filler-containing polyimide layer: thickness 3 μm) and layer-2 (on the glass substrate). A laminate L-10 in which a filler-free polyimide layer: thickness 20 μm) was formed in this order was obtained (thickness of polyimide coating: 23 μm).
The peeling property of the laminated body L-10 was evaluated in the same manner as in Example 1.

[Judgment of the light-to-heat strange換能]
The photothermal varying換能of the filler which is used to form the layers -1 in each example / comparative example was determined according to the "method of determining the photothermal varying換能" described above. In the "method of determining photothermal varying換能", formed of heat resistant organic polymer film, unless otherwise stated, it was performed according to the method of forming the layer-1 each example / comparative example.

As shown in Table 1, in the laminates L-1 to L-6 of the present invention, since the layer-1 in contact with the glass substrate contains the filler having the photothermal conversion ability, the peeling property was good. I know that there is. On the other hand, since the layer-1 of the laminated body L-8 shown in Comparative Example 2 contains the filler having no photothermal conversion ability, it is understood that the peeling property is poor. Further, in the polyimide coating containing no filler, the peeling property may be either a single layer like the laminate L-9 of Comparative Example 3 or two layers like the laminate L-7 of Comparative Example 1. It turns out that is bad.

The heat-resistant organic polymer layer peeling method of the present invention is useful for manufacturing flexible devices, flexible wiring boards, and flexible substrates.

Claims (9)

A laminate having at least one heat-resistant organic polymer layer formed on a substrate is irradiated with a continuous light beam in a wide wavelength range to separate at the interface between the substrate and the heat-resistant organic polymer layer. A method for peeling a heat-resistant organic polymer layer, which comprises:
A peeling method, wherein a heat-resistant organic polymer layer A containing a filler having a photothermal conversion ability is formed in contact with the substrate in the laminate. The peeling method according to claim 1, wherein in the laminate, at least the heat-resistant organic polymer layer A and the heat-resistant organic polymer layer B containing no filler are formed in this order on the substrate. The peeling method according to claim 1, wherein the heat-resistant organic polymer is polyimide. The peeling method according to claim 1, wherein the light source for irradiating the light beam is a flash lamp. Irradiating the laminated body with the light beam from the substrate side,
The peeling method according to any one of claims 1 to 4, wherein the substrate transmits a light beam in at least a part of the wavelength band of the irradiated wavelength band. The peeling method according to claim 5, wherein the substrate is a glass substrate, a polycrystalline substrate, or a single crystal substrate. Said filler having a photothermal varying換能is, graphite, carbon black, carbon nanotube, carbon nano sheet, graphene, diamond-like carbon, iron oxide, nickel oxide, copper oxide, titanium, aluminum, molybdenum, silicon particles, Achin pigments, phthalocyanine The peeling method according to claim 1, which is one or more fillers selected from the group consisting of pigments. The peeling method according to claim 1, wherein the heat-resistant organic polymer layer A contains the filler in an amount of 5 to 50 mass% with respect to the total mass thereof. A heat-resistant organic polymer layer A containing a filler having a photothermal conversion ability, a heat-resistant organic polymer layer B not containing the filler, and an electronic element are formed in this order on a substrate. Item 9. A method for manufacturing a flexible device or a flexible wiring board, to which the peeling method according to any one of Items 1 to 8 is applied.