KR102368739B1 - Manufacturing method of heat-resistant adhesive sheet and functional film - Google Patents

Abstract

(Project) To provide the manufacturing method of the heat-resistant adhesive sheet and functional film which can reduce the manufacturing cost of the functional film by manufacturing process shortening.
(Solution) The heat-resistant adhesive sheet 1 of the present invention includes a release base material 11 made of a polyester film, a resin layer 12 formed on one main surface of the release base material 11, and a release base material 11 a release film 10 including a release agent layer 13 formed on the other main surface of the It is characterized in that the Δ haze value, which is an absolute value of the difference between the initial haze value of the release film 10 and the haze value after heating at 150° C. for 2 hours, is 0.15% or less.

Description

The manufacturing method of a heat-resistant adhesive sheet and a functional film TECHNICAL FIELD

The present invention relates to a method for producing a heat-resistant pressure-sensitive adhesive sheet and a functional film having a functional layer, and more particularly, to a method for producing a heat-resistant pressure-sensitive adhesive sheet and a functional film using a polyester film as a release substrate.

Conventionally, in the manufacturing process of a touchscreen, the transparent conductive film provided with transparent electrode layers, such as an ITO (Indium Tin Oxide) film|membrane, is used. This transparent conductive film forms a hard-coat layer on a pair of main surfaces of a support body, respectively, while forming a transparent electrode layer on one hard-coat layer, surface protection on the other hard-coat layer It is manufactured by bonding the adhesive sheet as a film so that peeling is possible. As an adhesive sheet used for manufacture of a transparent conductive film, what formed the adhesive layer on the base film which consists of a polyester film which has heat resistance is proposed (for example, refer patent document 1).

Moreover, in the manufacturing process of a touchscreen, a transparent conductive film is stuck to a glass substrate etc. via the adhesive film for optics (Optical Clear Adhesive, hereafter "OCA" may be called). The release film which consists of a polyester film is laminated|stacked on both surfaces of an OCA normally.

Japanese Laid-Open Patent Publication No. 2003-205567

By the way, in the manufacturing process of a transparent conductive film, on the other surface of the transparent conductive film (or the raw material film of a transparent conductive film) in which the transparent conductive layer was formed on one surface, the peeling base material which has an adhesive layer protects a transparent conductive layer. The adhesive sheet as a film is affixed. Then, after performing annealing treatment of heating the transparent conductive film in a state in which the adhesive sheet is attached, the peeling substrate of the adhesive sheet is removed and the transparent conductive film is attached to a glass substrate or the like through an adhesive layer. Used in products such as touch panels do. As described above, in the conventional manufacturing process of a transparent conductive film, heat resistance is required for the adhesive sheet to be heat-treated together with the transparent conductive layer, and the process of attaching the adhesive sheet to the back side of the transparent conductive film of the transparent conductive film is Essentially, the manufacturing process may become complicated.

The present invention was made in view of such a situation, and an object of the present invention is to provide a heat-resistant pressure-sensitive adhesive sheet and a method for producing a functional film that are excellent in heat resistance and can reduce the production cost of a functional film by shortening the production process.

The heat-resistant pressure-sensitive adhesive sheet of the present invention comprises a release film comprising a release substrate made of a polyester film, a resin layer formed on one main surface of the release substrate, and a release agent layer formed on the other main surface of the release substrate; A pressure-sensitive adhesive layer formed on the release agent layer and a base film formed on the pressure-sensitive adhesive layer are provided, and the Δhaze value, which is the absolute value of the difference between the initial haze value of the release film and the haze value after heating at 150°C for 2 hours, is 0.15% It is characterized by the following.

According to this structure, since the change rate of the haze value of the peeling film before and behind a heating is small, the heat resistant adhesive sheet excellent in heat resistance can be implement|achieved. Moreover, since the back side with respect to the functional layer on a base film can be protected by the peeling film containing a peeling base material, a resin layer, and a release agent layer, when manufacturing a functional film, the protective sheet which protects the back side of a functional layer It becomes possible to omit the process of bonding together. Therefore, the heat resistant adhesive sheet which can reduce the manufacturing cost of the functional film by manufacturing process shortening can be implement|achieved.

In the heat resistant adhesive sheet of this invention, it is preferable that the said release agent layer hardens|cures addition-reaction type silicone.

In the heat-resistant adhesive sheet of the present invention, the resin layer is formed by curing a composition for forming a resin layer containing (A) a bisphenol A epoxy compound, (B) a polyester compound, and (C) a polyfunctional amino compound. it is preferable According to this structure, since a resin layer is formed on one surface of a peeling base material by hardening the composition for resin layer formation containing a bisphenol A epoxy resin compound, a polyester compound, and a polyfunctional amino compound, the crosslinking density of a resin layer is an appropriate range. Thereby, the heat resistant adhesive sheet becomes possible to prevent precipitation of the oligomer with respect to the surface side of the heat resistant adhesive sheet from a polyester film, and even if pressure or an impact is applied to the heat resistant adhesive sheet, it prevents the occurrence of cracks in the resin layer. Thus, it is possible to prevent the oligomer from leaking from the crack.

In the heat resistant adhesive sheet of this invention, in the said composition for resin layer formation, content of the said bisphenol A epoxy compound is 50 mass % or more and 80 mass % or less, and content of the said polyester compound is 5 mass % or more and 30 mass %. It is below, and it is preferable that content of the said polyfunctional amino compound is 10 mass % or more and 40 mass % or less.

In the heat resistant adhesive sheet of this invention, it is preferable that the weight average molecular weights of the said bisphenol-type epoxy compound are 10000 or more and 50000 or less.

In the heat resistant adhesive sheet of this invention, it is preferable that the glass transition temperatures (Tg) of the said polyester compound are 0 degreeC or more and 50 degrees C or less.

In the heat resistant adhesive sheet of this invention, it is preferable that the said resin layer apply|coats the solution of the said composition for resin layer formation on the said base film, and it is what heated the application layer formed, and it is what made it a cured film.

In the heat resistant adhesive sheet of this invention, it is preferable that the film thickness of the said resin layer are 50 nm or more and 500 nm or less.

The method for producing a functional film of the present invention is a release film comprising a release substrate made of a polyester film, a resin layer formed on one main surface of the release substrate, and a release agent layer formed on the other main surface of the release substrate On the release agent layer, the pressure-sensitive adhesive layer and the base film are laminated in this order, and the Δ haze value, which is the absolute value of the difference between the initial haze value of the release film and the haze value after heating at 150° C. for 2 hours, is 0.15 % or less, a lamination process of obtaining a heat-resistant adhesive sheet, a film-forming process of forming a conductive material as a functional layer on the base film of the heat-resistant adhesive sheet, and a heat treatment process of heat-treating the heat-resistant adhesive sheet on which the functional layer is formed characterized by including.

According to this method, since the back side with respect to the functional layer formed on the base film can be protected by the peeling film containing a peeling base material, a resin layer, and a release agent layer, when manufacturing a functional film, the back side of a functional layer It becomes possible to abbreviate|omit the process of bonding together the protective sheet|seat to protect. Therefore, the heat resistant adhesive sheet which can reduce the manufacturing cost of the functional film by manufacturing process shortening can be implement|achieved.

In the manufacturing method of the functional film of this invention, it is preferable that the said functional layer is a transparent conductive layer.

ADVANTAGE OF THE INVENTION According to this invention, while being excellent in heat resistance, it is realizable to provide the manufacturing method of the heat resistant adhesive sheet and functional film which can reduce the manufacturing cost of the functional film by manufacturing process shortening.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing of the heat resistant adhesive sheet which concerns on one Embodiment of this invention.
It is a cross-sectional schematic diagram of the laminated body which concerns on one Embodiment of this invention.
It is a schematic cross section which shows the other example of the heat resistant adhesive sheet which concerns on one Embodiment of this invention.
It is explanatory drawing of the manufacturing method of the functional film which concerns on embodiment of this invention.
It is explanatory drawing of the manufacturing method of the functional film which concerns on embodiment of this invention.
It is explanatory drawing of the manufacturing method of the functional film which concerns on embodiment of this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited to the following embodiment, It can change suitably and can implement. In addition, the same code|symbol is attached|subjected to the component common in the following embodiment, and duplication of description is avoided.

1 : is a schematic sectional drawing of the heat resistant adhesive sheet 1 which concerns on one Embodiment of this invention. As shown in FIG. 1, the heat resistant adhesive sheet 1 which concerns on this embodiment is formed on the one main surface of the peeling base material 11 which consists of a polyester film, this peeling base material 11, For resin layer formation A release film (10) comprising: a resin layer (12) formed by curing the composition; . On the release agent layer 13 of the release film 10, the base film 21 is laminated|stacked through the adhesive layer 14. As shown in FIG. That is, in this heat-resistant adhesive sheet 1, the resin layer 12, the peeling base material 11, the release agent layer 13, the adhesive layer 14, and the base film 21 are laminated|stacked in this order.

On the base film 21, the transparent conductive layer etc. as the functional layer 22 are formed (refer FIG. 2). After the heat resistant adhesive sheet 1 which concerns on this embodiment forms a transparent conductive material into a film on the base film 21, forms the functional layer 22, and sets it as the laminated body 3, in the laminated body 3 state It is possible to form a transparent conductive layer through the annealing process by heating. Moreover, although a transparent conductive layer is mentioned as the functional layer 22, for example, it is not restrict|limited to this.

The heat-resistant adhesive sheet 1 which concerns on this embodiment is wound up by the core material in roll shape, and can be stored. This adhesive sheet 1 is unwound from the state wound up in roll shape, for example, after predetermined heat processing is performed, the peeling film 10 is removed, and the surface on which the adhesive layer 14 is exposed is attached to a to-be-adhered body. It is used for manufacture of various products by sticking. As a to-be-adhered body, a glass substrate is mentioned, for example. As predetermined heat processing, various heat processing can be performed within the range which exhibits the effect of this invention, For example, the annealing process for crystallization of a transparent conductive material is mentioned.

The heat-resistant pressure-sensitive adhesive sheet 1 according to the present embodiment, for example, forms a transparent conductive material as the functional layer 22 as described above, and then heats and anneals to produce a transparent conductive film used for a touch panel or the like. can be used for In this heat resistant adhesive sheet 1, the (DELTA) haze value which is the absolute value of the difference between the initial haze value of the peeling film 10 and the haze value after heating after heating at 150 degreeC for 2 hours is 0.15 % or less. As a result, even when a transparent conductive layer as the functional layer 22 is formed on the heat-resistant pressure-sensitive adhesive sheet 1 and annealing by heating is performed, the change in haze value of the release film before and after the annealing treatment is sufficiently small, so that it is transparent. It becomes possible to anneal with the heat resistant adhesive sheet 1 in which the conductive layer was provided with the adhesive layer 14. Moreover, since the release film 10 is formed on the back side of the functional layer 22 (one surface side of the heat-resistant adhesive sheet 1) through the adhesive layer 14, the peeling film 10 is a prior art. It can also serve as the protective sheet affixed on the back surface of the transparent conductive film in this, and cost reduction by shortening of the manufacturing process of a transparent conductive film becomes possible. In addition, since the resin layer 12 formed of a predetermined composition for forming a resin layer is provided on the back side of the functional layer 22, precipitation of oligomers on one surface side of the heat-resistant adhesive sheet 1 can be prevented. Even when the functional layer 22 is formed into a film and wound in a roll shape on the core material, contamination and damage to the surface of the functional layer 22 are prevented despite the use of a polyester film as the release base material 11. can be prevented

3 : is a cross-sectional schematic diagram which shows the other structural example of the heat resistant adhesive sheet 1 which concerns on this embodiment. As shown in FIG. 3 , in this heat-resistant adhesive sheet 2 , the pressure-sensitive adhesive layer 14 of the heat-resistant adhesive sheet 2 is a core material 141 and a first formed on one surface of the core material 141 . The adhesive layer 142 and the 2nd adhesive layer 143 formed on the other surface of the core material 141 are included. As the core material 141, various films, such as a polyester film similar to the peeling base material 11, paper, a nonwoven fabric, etc. can be used, for example. The first pressure-sensitive adhesive layer 142 and the second pressure-sensitive adhesive layer 143 are made of the same material as the pressure-sensitive adhesive layer 14 . Also by comprising in this way, the effect similar to the heat resistant adhesive sheet 1 shown in FIG. 1 mentioned above can be acquired. Hereinafter, various components which comprise the heat resistant adhesive sheets 1 and 2 which concern on this embodiment are demonstrated.

(Releasable substrate (11))

As the peeling base material 11, various polyester films can be used. The polyester film is excellent in heat resistance, and even when annealing a transparent electrode layer such as a transparent conductive film at a high temperature, problems such as shrinkage and melting do not occur. As a polyester film, polyester films, such as a polyethylene terephthalate, a polybutylene terephthalate, and a polyethylene naphthalate, are preferable, for example. Moreover, as a polyester film, a biaxially stretched polyethylene terephthalate film is more preferable.

The thickness of the peeling base material 11 can be changed suitably according to a use. The thickness of the release substrate 11 is preferably 10 µm or more, from the viewpoint of maintaining the strength of the heat-resistant pressure-sensitive adhesive sheet, and from the viewpoint of ensuring flexibility in the production of a transparent conductive film by a roll-to-roll method, 20 micrometers or more are more preferable, 30 micrometers or more are still more preferable, 250 micrometers or less are preferable, 225 micrometers or less are more preferable, and 200 micrometers or less are still more preferable. When the above is considered, 10 micrometers or more and 250 micrometers or less are preferable, as for the thickness of the peeling base material 11, 20 micrometers or more and 225 micrometers or less are more preferable, and their 30 micrometers or more and 200 micrometers or less are still more preferable.

(resin layer (12))

From the viewpoint of preventing precipitation of the oligomer from the release base material 11, the resin layer 12 includes (A) a bisphenol A epoxy compound (hereinafter also simply referred to as “component (A)”) and (B) poly Cured film obtained by curing a composition for forming a resin layer containing an ester compound (hereinafter also simply referred to as “component (B)”) and (C) a polyfunctional amino compound (hereinafter also simply referred to as “component (C)”). It is preferable to be Hereinafter, each component which comprises the composition for resin layer formation is demonstrated in detail.

<(A) Bisphenol A epoxy compound>

(A) As a bisphenol A epoxy compound, the bisphenol A epoxy resin etc. which are copolymers of bisphenol A and epichlorohydrin are mentioned, for example.

It is preferable that a weight average molecular weight (Mw) of component (A) is 10000 or more and 50000 or less from a viewpoint of being able to obtain the cured film of moderate crosslinking density. (A) When the weight average molecular weight (Mw) of component is 10000 or more, sufficient crosslinking density as a cured film is obtained, and it becomes possible to fully prevent precipitation of an oligomer. In addition, when the weight average molecular weight (Mw) of component (A) is 50000 or less, it is possible to impart appropriate flexibility to the cured film, and to prevent cracks in the resin layer 12 when the heat-resistant adhesive sheet 1 is deformed. can

50 mass % or more is preferable with respect to the total mass of the composition for resin layer formation, as for the compounding quantity of (A) component in the composition for resin layer formation, 60 mass % or more is more preferable, and 80 mass % or less is preferable. and 70 mass % or less is more preferable.

<(B) polyester compound>

(B) As a polyester compound, various well-known polyester compounds can be used in the range which exhibits the effect of this invention. As a polyester compound, resin obtained by the condensation reaction of a polyhydric alcohol and a polybasic acid is mentioned, for example. As such a resin, an invertible polyester compound obtained by modifying a condensate of a dibasic acid and a dihydric alcohol or a condensate of a non-drying oil fatty acid, etc., and an invertible polyester compound which is a condensate of a dibasic acid and a trihydric or higher alcohol can be heard A polyester compound may be used individually by 1 type, and may use 2 or more types together.

Examples of the polyhydric alcohol include dihydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, and neopentyl glycol, glycerin, trimethylolethane, and trimethylol. tetrahydric or higher polyhydric alcohols, such as trihydric alcohols, such as propane, diglycerol, triglycerol, pentaerythritol, dipentaerythritol, mannit, and sorbit, are mentioned. These polyhydric alcohols may be used individually by 1 type, and may use 2 or more types together.

As polybasic acid, For example, aromatic polybasic acids, such as phthalic anhydride, terephthalic acid, isophthalic acid, and trimetic anhydride, aliphatic saturated polybasic acids, such as succinic acid, adipic acid, and sebacic acid, maleic acid, maleic anhydride, fumaric acid , itaconic acid, and aliphatic unsaturated polybasic acids such as citraconic anhydride, cyclopentadiene-maleic anhydride adduct, terpene-maleic anhydride adduct, and rosin-maleic anhydride adduct obtained by Diels-Alder reaction A polybasic acid etc. are mentioned. These polybasic acids may be used individually by 1 type, and may use 2 or more types together.

(B) As a polyester compound, what has active hydrogen groups, such as a hydroxyl group used as a reaction point of a crosslinking reaction, a carboxyl group, and an amino group, is preferable, and what has a hydroxyl group is more preferable. (B) The polyester compound preferably has a hydroxyl value of 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, more preferably 500 mgKOH/g or less, and more preferably 300 mgKOH/g or less.

(B) the polyester compound has a number average molecular weight (Mn) of preferably 500 or more, more preferably 1000 or more, and preferably 10000 or less, from the viewpoint of imparting appropriate flexibility to the resin layer (12). , it is more preferably 5000 or less. (B) The polyester compound preferably has a glass transition temperature (Tg) of 0 ° C. or higher, preferably 10 ° C. or higher, and 50 ° C. or lower from the viewpoint of imparting appropriate flexibility to the resin layer 12. It is preferable, and it is more preferable that it is 40 degrees C or less. By using such a polyester compound (B), moderate flexibility can be imparted to the cured film of the resin layer 12, and cracks in the resin layer 12 are prevented even when the heat-resistant adhesive sheet 1 is subjected to pressure or impact. This can prevent leakage of oligomers due to cracks.

5 mass parts or more are preferable with respect to 100 mass parts of (A) component, as for the compounding quantity of (B) component in the composition for resin layer formation, 10 mass parts or more are more preferable, and 50 mass parts or less are preferable. and 45 parts by mass or less is more preferable.

5 mass % or more is preferable with respect to the total mass of the composition for resin layer formation, as for the compounding quantity of (B) component in the composition for resin layer formation, 10 mass % or more is more preferable, and 30 mass % or less is preferable. and 20 mass % or less is more preferable.

<(C) polyfunctional amino compound>

(C) Examples of the polyfunctional amino compound include melamine compounds such as hexamethoxymethylmelamine, methylated melamine compound, and butylated melamine compound, methylated urea compound, and butylated urea compound, such as urea compounds, methylated benzo Benzoguanamine compounds such as guanamine resins and butylated benzoguanamine compounds, diamines such as ethylenediamine, tetramethylenediamine, hexamethylenediamine, N,N'-diphenylethylenediamine, and p-xylylenediamine can be heard Among these, the viewpoint of sclerosis|hardenability to hexamethoxymethylmelamine is preferable.

20 mass parts or more is preferable with respect to 100 mass parts of (A) component, as for the compounding quantity of (C)component in the composition for resin layer formation, 25 mass parts or more are more preferable, and 60 mass parts or less are preferable, , 55 parts by mass or less is more preferable.

10 mass % or more is preferable with respect to the total mass of the composition for resin layer formation, as for the compounding quantity of (C)component in the composition for resin layer formation, 20 mass % or more is more preferable, and its 40 mass % or less is preferable. and 30 mass % or less is more preferable.

<(D) acid catalyst>

The composition for forming a resin layer contains, if necessary, a known acid catalyst (D) such as hydrochloric acid and p-toluenesulfonic acid (hereinafter also simply referred to as “component (D)”) in order to accelerate the curing reaction. You may use it. (D) When mix|blending component, it is preferable to make content of (D)component into 1 mass % or more and 5 mass % or less with respect to the total mass of the composition for resin layer formation.

The resin layer 12 is formed by applying a solution obtained by dissolving the composition for forming a resin layer in an organic solvent on the release substrate 11 to form a coating layer, and applying the formed coating layer at a temperature of 100°C or higher and 170°C or lower for 5 seconds. It is obtained by heat-hardening for more than 5 minutes or less. As a coating method of the composition for forming a resin layer, for example, a gravure coating method, a bar coating method, a spray coating method, a spin coating method, an air knife coating method, a roll coating method, a blade coating method, a gate roll coating method, and The die coating method etc. are mentioned. Among these, the gravure coating method and the bar coating method are preferable, and the bar coating method is more preferable. Moreover, as a heating and drying method of the composition for resin layer formation, the method of heat-drying in a hot-air drying furnace etc. are mentioned, for example.

The organic solvent is not particularly limited as long as it can dissolve the composition for forming a resin layer. Examples of the organic solvent include aromatic solvents such as benzene, toluene and xylene, aliphatic solvents such as normal hexane and normal heptane, ester solvents such as ethyl acetate and butyl acetate, methyl ethyl ketone, Alcohol solvents, such as ketone solvents, such as methyl isobutyl ketone, cyclohexanone, and cyclopentanone, isopropyl alcohol, and methanol, etc. are mentioned.

The film thickness of the resin layer 12 is preferably 50 nm or more, more preferably 80 nm or more, still more preferably 100 nm or more, and preferably 500 nm or less, from the viewpoint of effectively suppressing oligomer precipitation, and 300 nm or more. nm or less is more preferable, and 250 nm or less is still more preferable. If the film thickness of the resin layer 12 is 50 nm or more, it becomes possible to fully suppress oligomer precipitation, and if it is 500 nm or less, the resin layer at the time of coating and forming the resin layer 12 on the peeling base material 11. (12) Curl|Karl by cure shrinkage accompanying bridge|crosslinking can be prevented. In consideration of the above, the film thickness of the resin layer 12 is preferably 50 nm or more and 500 nm or less, more preferably 80 nm or more and 300 nm or less, and still more preferably 100 nm or more and 250 nm or less.

(Releasant Layer (13))

The release agent layer 13 is formed from the hardened|cured material of the composition for release agent layer formation containing a mold release agent, for example. As a composition for release agent layer formation, if the release agent layer 13 can provide the function of peeling the adhesive layer 14 laminated|stacked on the release agent layer 13 from the release film 10, there will be no restriction|limiting in particular. As a mold release agent, a silicone resin, a long-chain alkyl resin, an alkyd resin, etc. are mentioned, for example.

Examples of the silicone-based mold release agent include addition-reaction silicone, condensation-reaction silicone, and energy ray-curable silicone. Moreover, in order to adjust peeling force, you may use non-functional polydimethylsiloxane, a phenyl-modified silicone, a silicone resin, a silica, and a cellulose compound as an additive.

The thickness of the release agent layer 13 is preferably 30 nm or more, preferably 50 nm or more, more preferably 70 nm or more, more preferably 500 nm or less, more preferably 400 nm or less, and more preferably 300 nm or less. is more preferable. When the thickness of the release agent layer 13 is in such a range, it is easy to obtain a uniform release performance between the release film 10 and the pressure-sensitive adhesive layer 14, and when the release film 10 is wound in a roll shape, contact Blocking of the surfaces of the peeling film 10 can be prevented.

The release agent layer 13 is formed by, for example, applying the composition for forming a release agent layer to one surface of the release base material 11 by a conventionally known coating method, followed by heating at a predetermined temperature, drying and curing. Here, the composition for releasing agent layer formation may coat what diluted with the organic solvent on the peeling base material 11. Examples of the organic solvent include aromatic hydrocarbons such as toluene and xylene, fatty acid esters such as ethyl acetate and butyl acetate, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and aliphatic hydrocarbons such as hexane and heptane.

As a coating method of the composition for release agent layer formation, for example, a gravure coating method, a bar coating method, a spray coating method, a spin coating method, an air knife coating method, a roll coating method, a blade coating method, a gate roll coating method, and The die coating method etc. are mentioned. Among these, the gravure coating method and the bar coating method are preferable, and the bar coating method is more preferable. Moreover, as a heating and drying method of the composition for release agent layer formation, the method of heat-drying in a hot-air drying furnace etc. are mentioned, for example. Drying temperature is 50 degreeC or more and 150 degrees C or less, for example. Moreover, it is preferable that drying time is 10 second - 5 minutes, for example.

(Releasable Film (10))

As for the release film 10, the above-mentioned resin layer 12, the release base material 11, and the release agent layer 13 are laminated|stacked in this order, and are comprised. As thickness of the peeling film 10, 10 micrometers or more are preferable, for example, 15 micrometers or more are more preferable, 200 micrometers or less are preferable, and 100 micrometers or less are more preferable.

(Adhesive layer (14))

In the heat resistant adhesive sheet 1 which concerns on this embodiment, the adhesive layer 14 is heat-processed in the state pinched|interposed between the peeling base material 11 and the base film 21. In this heat treatment, since the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 14 is exposed to high temperature, when a general pressure-sensitive adhesive having low heat resistance is used, the viscosity of the pressure-sensitive adhesive decreases, and the pressure-sensitive adhesive layer from the ends of the base film 21 and the release film 10 (14) This protrusion phenomenon may occur. The pressure-sensitive adhesive layer 14 protruding from the ends of the base film 21 and the release film 10 is transferred to the object in contact with the pressure-sensitive adhesive and contaminates the contacted article (for example, a conveyance roll of an annealing apparatus and surface contamination by redeposition to the heat-resistant adhesive sheet) may occur.

Then, in this embodiment, as the adhesive layer 14, the storage elastic modulus in 23 degreeC from a viewpoint of improving the heat resistance at the time of heat processing of the adhesive layer 14, and a viewpoint from a viewpoint which adhesive durability becomes more favorable. (G) It is preferable that it is 0.3 MPa or more, It is more preferable that it is 0.35 MPa or more, It is preferable that it is 50 MPa or less, It is more preferable that it is 15 MPa or less, It is more preferable that it is 12 MPa or less. In addition, in this embodiment, the storage elastic modulus (G) laminates|stacks an adhesive layer with a thickness of 30 micrometers, produces a column-shaped test piece with a thickness of 8 mm phi x 3 mm, and by a torsion shearing method, under the following conditions is the measured value.

Measuring device: Dynamic viscoelasticity measuring device (Model No.: DYNAMIC ANALYZER RDAII, manufactured by Rheometric)

Frequency: 1 Hz

Temperature: 23℃, 80℃

In addition, as the pressure-sensitive adhesive layer 14, from the viewpoint of heat resistance, durability, and stability of the pressure-sensitive adhesive layer 14, and from the viewpoint of preventing contamination of the pressure-sensitive adhesive to an adherend, it is preferable that the gel fraction is 85% or more, 90 It is more preferable that it is 99.9 % or more.

The pressure-sensitive adhesive layer 14 is an acrylic pressure-sensitive adhesive, a natural rubber-based pressure-sensitive adhesive, a synthetic rubber-based pressure-sensitive adhesive, a polyether-based pressure-sensitive adhesive, a polyester-based pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, and a conventionally known composition for forming a pressure-sensitive adhesive layer such as a urethane-based pressure-sensitive adhesive is formed As an acrylic adhesive, the composition for adhesive layer formation containing an acrylic polymer is mentioned, for example. The pressure-sensitive adhesive is supplied in a form such as a solvent type, an emulsion type, a hot melt solvent-free type, and an ultraviolet curing solvent-free type, and the pressure-sensitive adhesive layer 14 is formed by a coating method suitable for each type.

<Acrylic polymer>

The acrylic polymer is obtained by polymerizing a (meth)acrylic acid ester, a vinyl monomer containing a reactive group such as a hydroxyl group and a carboxyl group, and a monomer containing an aromatic monomer or the like.

As (meth)acrylic acid ester, For example, (meth)acrylic acid methyl, (meth)acrylate, (meth)acrylic acid-n-propyl, (meth)acrylic acid isopropyl, (meth)acrylic acid-n-butyl, ( Isobutyl meth)acrylate, (meth)acrylic acid-sec-butyl, (meth)acrylic acid-t-butyl, (meth)acrylic acid-n-pentyl, (meth)acrylic acid-n-hexyl, (meth)acrylic acid cyclohexyl, ( Meth) acrylic acid-2-ethylhexyl, (meth) acrylate isooctyl, (meth) acrylic acid decyl, (meth) acrylate dodecyl, (meth) acrylate myristyl, (meth) acrylate palmityl, and (meth) acrylate stearyl and (meth)acrylic acid alkylesters having 1 or more and 20 or less carbon atoms of the alkyl group of the ester moiety, such as these. Here, "(meth)acryl" represents "acryl" or "methacryl." These acrylic monomers may be used individually by 1 type, and may use 2 or more types together.

As a vinyl monomer containing a reactive functional group, For example, hydroxyl-containing (meth)acrylates, such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate; 1,4-di(meth)acryloxyethyl pyromellitic acid, 4-(meth)acryloxyethyl trimellitic acid, N-(meth)acryloyl-p-aminobenzoic acid, 2-(meth)acryloyloxy carboxyl group-containing (meth)acrylates such as benzoic acid, N-(meth)acryloyl-5-aminosalicylic acid, acrylic acid, and methacrylic acid; Primary and secondary amino group-containing (meth)acrylates, such as aminoethyl (meth)acrylate, ethylaminoethyl (meth)acrylate, aminopropyl (meth)acrylate, and ethylaminopropyl (meth)acrylate; and thiol group-containing (meth)acrylates such as 2-(methylthio)ethyl methacrylate. These may be used individually by 1 type, and may use 2 or more types together.

The content of the structural unit derived from the vinyl monomer containing the reactive functional group in the acrylic polymer is preferably 0.01 mol% or more, more preferably 0.1 mol% or more, preferably 20 mol% or less, and 10 mol% or less more preferably.

As an aromatic monomer, the high refractive index acrylic monomer in which a homopolymer shows the glass transition temperature of 50 degrees C or less from a viewpoint of improving the refractive index of the adhesive layer 14 is preferable.

As an aromatic monomer, For example, phenoxyethyl (meth)acrylate, 2-(1-naphthyloxy)-1-ethyl (meth)acrylate, 2-(2-naphthyloxy)-1-ethyl (meth)acrylate, 6-(1-naphthyloxy)-1-hexyl (meth)acrylate, 6-(2-naphthyloxy)-1-hexyl (meth)acrylate, 8-(1-naph Tyloxy)-1-octyl (meth) acrylate, 8- (2-naphthyloxy) -1-octyl (meth) acrylate, 2-phenylthio-1-ethyl (meth) acrylate, 6- (4 ,6-dibromo-2-isopropylphenoxy)-1-hexyl (meth)acrylate, 6-(4,6-dibromo-2-s-butylphenoxy)-1-hexyl (meth) acrylate, 2,6-dibromo-4-nonylphenyl (meth)acrylate, and 2,6-dibromo-4-dodecylphenyl (meth)acrylate.

It is preferable to contain an acryl-type triblock copolymer as a composition for adhesive layer formation. The acrylic triblock copolymer is represented by the following general formula (1) and has a weight average molecular weight (Mw) of 50,000 or more and 300,000 or less, a molecular weight distribution (Mw/Mn) of 1.0 to 1.5, and the content of the polymer block B is It is preferable that they are 50 mass % or more and 95 mass % or less.

A1-B-A2 Formula (1)

(In formula (1), A1 and A2 each independently represent an alkyl methacrylate polymer block having a glass transition temperature of 100°C or higher, and B represents an acrylic acid alkylester polymer block having a glass transition temperature of -20°C or lower)

In the acrylic triblock copolymer represented by the general formula (1), the polymer blocks A1 and A2 are constrained phases in the acrylic triblock copolymer that form a microphase-separated structure at the normal operating temperature of the pressure-sensitive adhesive. (physical pseudo-crosslinking point). Thereby, even if chemical crosslinking is not performed, sufficient cohesive force is expressed, and the outstanding adhesive property and durability are exhibited. The polymer blocks A1 and A2 in the acrylic triblock copolymer represented by the general formula (1) have a glass transition temperature of 100° C. or more and 200° C. from the viewpoint of durability, heat resistance, followability to substrate deformation, and moderate stress relaxation property. It is preferable that they are below, and it is more preferable that they are 100 degreeC or more and 150 degrees C or less. In addition, as A1 and A2, polymers [same alkyl methacrylic acid ester polymer with the same molecular weight, monomer composition, three-dimensional structure (syndiotacticity, etc.), etc.] may be sufficient, and also different polymers [molecular weight, monomer composition, three-dimensional structure ( and syndiotacticity, etc.) and the like), and the like).

Examples of the methacrylic acid alkyl ester unit of the polymer blocks A1 and A2 include methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, and methacrylic acid. Acid n-hexyl, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, isobornyl methacrylate, etc. The unit which consists of methacrylic acid alkylester of is mentioned. Polymer blocks A1 and A2 may be formed in only one type of the above-mentioned methacrylic acid alkylester unit, and may be formed in two or more types. Among these, as polymer blocks A1 and A2, from a viewpoint of availability, durability, and a weather resistance, what is comprised by 1 type of methyl methacrylate unit is preferable.

As polymer block B, the polymer block whose glass transition temperature which consists of an acrylic acid alkylester from a viewpoint of the adhesive force of the adhesive layer 14 and rework property is -20 degreeC or less is preferable. As the polymer block B, from the viewpoint of stability under low-temperature conditions, a polymer block having a glass transition temperature of -30°C or less is more preferable, and a polymer block having a glass transition temperature of -80°C or more and -40°C or less is still more preferable.

Examples of the polymer block B include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, t-butyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, la acrylate. The unit which consists of acrylic acid alkylesters, such as uril, tridecyl acrylate, and stearyl acrylate, is mentioned. The polymer block B may be formed in only one type of the above-mentioned acrylic acid alkylester unit, and may be formed in two or more types. Among these, as the polymer block B, the glass transition point of the polymer block becomes -20 ° C. or less, so that the adhesive strength and tack at low temperatures of the pressure-sensitive adhesive become good, and the adhesive strength increase and the zipping phenomenon at the time of high-speed peeling can be suppressed. From a viewpoint, it is preferable to consist of 1 type, or 2 or more types of the unit which consists of propyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, and n-octyl acrylate. In addition, as the polymer block B, ease of availability and phase separation between the polymer blocks A1 and A2 and the polymer block B are clear, the pseudo-crosslinking point of the polymer block A does not collapse, the cohesive force as an adhesive is high, and from the viewpoint of becoming excellent in durability, acrylic acid It is preferably composed of n-butyl units and/or 2-ethylhexyl acrylate units.

As the polymer blocks A1, A2 and the polymer block B of the acrylic triblock copolymer represented by the general formula (1), a small amount (for example, usually 10 mass based on the mass of each polymer block) within the range exhibiting the effects of the present invention % or less), you may have another monomer unit. Examples of the other monomer unit include methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, (meth)acrylic acid 2 -(meth)acrylic acid ester, (meth)acrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid and (meth)acrylic acid having a functional group such as aminoethyl, (meth)acrylic acid glycidyl and (meth)acrylic acid tetrahydrofurfuryl ) Vinyl-based monomers having a carboxyl group such as acrylamide, aromatic vinyl-based monomers such as styrene, α-methylstyrene and p-methylstyrene, conjugated diene-based monomers such as butadiene and isoprene, olefinic monomers such as ethylene and propylene, ε - The unit which consists of lactone-type monomers, such as caprolactone and valerolactone, etc. is mentioned. These monomer units may contain individually by 1 type, and may contain 2 or more types.

There is no restriction|limiting in particular as a polymerization method of an acryl-type polymer, The general radical polymerization method can superpose|polymerize. As a radical polymerization method, solution polymerization, suspension polymerization, emulsion polymerization, block polymerization, etc. are mentioned.

The molecular weight of the acrylic polymer is preferably 500,000 or more, more preferably 600,000 or more, still more preferably 700,000 or more in terms of a weight average molecular weight from the viewpoint of heat resistance. As the weight average molecular weight of the acrylic polymer increases, entanglement of molecular chains increases, flow at high temperature is suppressed, and heat resistance is improved. Moreover, as molecular weight of an acryl-type polymer, 2 million or less are preferable in terms of a weight average molecular weight from a viewpoint of coatability or adhesiveness with a to-be-adhered body, and 1.8 million or less are preferable. When the upper limit of the weight average molecular weight of the acrylic polymer is this level, the composition for forming an adhesive layer can be coated without requiring excessive dilution, and the fluidity is not excessively insufficient, so that the adhesive layer follows the surface roughness of the adherend. This can be done to ensure adhesion. In addition, the said weight average molecular weight is a polystyrene conversion value measured by the gel permeation chromatography (GPC) method.

<Active energy ray-curable compound>

Moreover, as a composition for adhesive layer formation, it is preferable to contain an active energy ray-curable compound from a viewpoint of improving the elastic modulus of the adhesive layer 14, and a gel fraction. As the active energy ray-curable compound, for example, a polyfunctional (meth)acrylate-based monomer having a molecular weight of less than 1000, an acrylate-based oligomer, and an adduct acrylate-based polymer in which a group having a (meth)acryloyl group is introduced into the side chain. and the like.

Examples of the polyfunctional (meth)acrylate-based monomer having a molecular weight of less than 1000 include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and neopentylglycoldi(meth)acrylate. ) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, capro Bifunctional types such as lactone-modified dicyclopentenyldi(meth)acrylate, ethylene oxide-modified phosphate di(meth)acrylate, di(acryloxyethyl)isocyanurate, and allylated cyclohexyldi(meth)acrylate , trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide modified trimethylol Trifunctional types, such as propane tri (meth) acrylate and tris (acryloxyethyl) isocyanurate, tetrafunctional types, such as diglycerol tetra (meth) acrylate, and pentaerythritol tetra (meth) acrylate, 5 functional types such as propionic acid-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and 6 functional types such as caprolactone-modified dipentaerythritol hexa (meth) acrylate, etc. can be heard These polyfunctional (meth)acrylate-type monomers may be used individually by 1 type, and may use 2 or more types together.

As the polyfunctional (meth)acrylate-based monomer, one having a cyclic structure in the skeleton structure is preferable. The cyclic structure may be a carbocyclic structure, a heterocyclic structure, or a monocyclic structure or a polycyclic structure. Examples of the polyfunctional (meth)acrylate-based monomer include those having isocyanurate structures such as di(acryloxyethyl)isocyanurate and tris(acryloxyethyl)isocyanurate. , dimethyloldicyclopentane diacrylate, ethylene oxide-modified hexahydrophthalic acid diacrylate, tricyclodecane dimethanol acrylate, neopentyl glycol-modified trimethylolpropane diacrylate, and adamantane diacrylate.

As an acrylate-type oligomer, the thing of 50000 or less of weight average molecular weights is preferable. Examples of such acrylate oligomers include polyester acrylate oligomers, epoxy acrylate oligomers, urethane acrylate oligomers, polyether acrylate oligomers, polybutadiene acrylate oligomers, and silicone acrylates. system oligomer etc. are mentioned.

The polyester acrylate oligomer can be obtained by, for example, esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both terminals obtained by condensation of a polyhydric carboxylic acid and a polyhydric alcohol with (meth)acrylic acid. Moreover, the polyester acrylate type oligomer can also be obtained by esterifying the hydroxyl group of the terminal of the oligomer obtained by adding alkylene oxide to polyhydric carboxylic acid with (meth)acrylic acid.

The epoxy acrylate oligomer can be obtained by, for example, reacting (meth)acrylic acid with an oxirane ring of a relatively low molecular weight bisphenol-type epoxy resin or novolak-type epoxy resin to esterify it. Moreover, the epoxy acrylate oligomer of the carboxyl modification type|mold which modified|denatured this epoxy acrylate type oligomer partly with dibasic carboxylic acid anhydride can also be used. The urethane acrylate oligomer can be obtained by, for example, esterifying a polyurethane oligomer obtained by the reaction of polyether polyol or polyester polyol with polyisocyanate with (meth)acrylic acid, and the polyol acrylate oligomer, It can obtain by esterifying the hydroxyl group of polyether polyol with (meth)acrylic acid.

The weight average molecular weight of the acrylate-based oligomer is preferably 50000 or less in terms of standard polymethyl methacrylate measured by GPC method, more preferably 500 or more and 50000 or less, more preferably 3000 or more and 40000 or less. desirable. These acrylate-type oligomers may be used individually by 1 type, and may use 2 or more types together.

The adduct acrylate-based polymer in which a group having a (meth)acryloyl group is introduced into the side chain uses a copolymer of the above-mentioned (meth)acrylic acid ester and a monomer having a crosslinkable functional group in the molecule, and crosslinks the copolymer It can obtain by making a part of sexual functional group react with the compound which has a group which reacts with a (meth)acryloyl group and a crosslinkable functional group. The weight average molecular weights of an adduct acrylate type polymer are 500,000 or more and 2 million or less normally in conversion of polystyrene.

<Photoinitiator>

When using an energy-beam sclerosing|hardenable compound as a composition for adhesive layer formation, from a viewpoint of improving the elastic modulus of the adhesive layer 14, and a gel fraction, what contained the photoinitiator is used. Examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, and dimethylaminoacetophenone. , 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclo Hexylphenylketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan 1-one, 4-(2-hydroxyethoxy)phenyl-2-(hydroxy-2 -Propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethyl ketal; Acetophenone dimethyl ketal, p-dimethylaminobenzoic acid ester, oligo[2-hydroxy-2-methyl-1[4-(1-methylvinyl)phenyl]propanone], 2,4,6-trimethylbenzoyldiphenylphos Fin oxide etc. are mentioned. These may be used individually by 1 type, and may use 2 or more types together.

As a compounding quantity of a photoinitiator, 0.2 mass part or more and 20 mass parts or less are preferable with respect to 100 mass parts of energy-beam sclerosing|hardenable compounds.

<crosslinking agent>

As a composition for adhesive layer formation, it is preferable to contain a crosslinking agent (hardening|curing agent) from a viewpoint of improving the elastic modulus of the adhesive layer 14, and a gel fraction. The crosslinking agent is preferably at least one selected from the group consisting of polyfunctional isocyanate compounds such as polyfunctional amino compounds and polyisocyanate compounds, polyfunctional epoxy compounds, polyfunctional aziridine compounds, polyfunctional oxazoline compounds, and polyfunctional metal compounds. Do. As a crosslinking agent, what crosslinks an adhesive by reacting with the reactive functional group of an acrylic polymer can be used, for example. Moreover, as a composition for adhesive layer formation, what contains a hardening accelerator, a hardening retarder, etc. can also be used.

Specific examples of the polyfunctional isocyanate compound include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4, 4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, Dicyclohexylmethane-2,4'-diisocyanate, lysine isocyanate, etc. are mentioned. Moreover, the terminal isocyanate urethane prepolymer etc. which are obtained by making the trimer of these polyfunctional isocyanate compounds, and these polyfunctional isocyanate compounds and a polyol compound react can also be used.

Specific examples of the polyfunctional epoxy compound include 1,3-bis(N,N-diglycidylaminomethyl)benzene, 1,3-bis(N,N-diglycidylaminomethyl)toluene, N, N,N',N'-tetraglycidyl-4,4-diaminodiphenylmethane and the like.

Specific examples of the polyfunctional aziridine compound include N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide)trimethylolpropanetri-β-aziridinylpropionate, tetramethyl olmethane tri-β-aziridinyl propionate, N,N'-toluene-2,4-bis(1-aziridinecarboxamide)triethylenemelamine, etc. are mentioned.

Specific examples of the polyfunctional oxazoline compound include addition polymerizable 2-oxazoline and other unsaturated monomers having a substituent having an unsaturated carbon-carbon bond at the 2-position carbon position, such as 2-isopropenyl-2-oxazoline. of copolymers and the like.

Specific examples of the polyfunctional metal compound include coordination compounds of polyvalent metals such as aluminum chelate compounds such as aluminum trisethylacetacetate, aluminum ethylacetoacetate diisopropylate, and trisacetylacetonatoaluminum. Among these, an aluminum chelate type compound is preferable from a viewpoint of obtaining sufficient adhesive force.

The composition for adhesive layer formation WHEREIN: A crosslinking agent may be used individually by 1 type, and may be used combining two or more types of crosslinking agents. In order to improve the heat resistance of the pressure-sensitive adhesive layer, it is preferable to combine different types of crosslinking agents. As a specific example in the case of combining different types of crosslinking agents, the combination of a polyfunctional isocyanate compound and a polyfunctional epoxy compound, and the combination of a polyfunctional isocyanate compound and a polyfunctional metal compound are preferable.

As a compounding amount of the crosslinking agent, from the viewpoint of forming an adhesive layer excellent in adhesive performance and cohesive strength, 0.1 parts by mass or more of the crosslinking agent per 100 parts by mass of the acrylic polymer is preferable, and more preferably 1 part by mass or more, Moreover, 30 mass parts or less are preferable, and 20 mass parts or less are more preferable.

<Silane coupling agent>

As a composition for adhesive layer formation, you may use what contained the silane coupling agent as needed. By containing this silane coupling agent, when bonding a transparent conductive film together to a glass substrate etc., the adhesiveness between an adhesive layer and a glass cell becomes favorable, for example. As a silane coupling agent, it is an organosilicon compound which has at least 1 alkoxysilyl group in a molecule|numerator, Compatibility with an adhesive component is favorable, and what has light transmittance is preferable.

Examples of the silane coupling agent include polymerizable unsaturated group-containing silicon compounds such as vinyltrimethoxysilane, vinyltriethoxysilane, and methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane Silicon compounds having an epoxy structure such as , 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrime and amino group-containing silicon compounds such as oxysilane and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, and the like. These may be used individually by 1 type, and may be used in combination of 2 or more type.

As a compounding quantity of a silane coupling agent, 0.001 mass part or more and 10 mass parts or less are preferable with respect to 100 mass parts of solid content of the composition for adhesive layer formation, and 0.005 mass part or more and 5 mass parts or less are more preferable.

<Tackifying resin>

As a composition for adhesive layer formation, you may use what contains tackifying resin which adjusts a tack|tack, adhesive force, and holding|maintenance force. Examples of the tackifying resin include coal-based tackifying resins such as rosin-based tackifying resins, terpene-based tackifying resins, petroleum-based tackifying resins, and coumarone-indene-based resins, phenolic resins, xylene resins, styrene-based resins, and their Outside tackifying resin etc. are mentioned. Examples of the rosin tackifying resin include gum rosin, tall oil rosin, wood rosin, hydrogenated rosin, disproportionated rosin, polymerized rosin, glycerol ester of modified rosin, and pentaerythritol ester of modified rosin. As terpene type tackifying resin, (alpha)-pinene resin, (beta)-pinene resin, dipentene resin, aromatic modified terpene resin, terpene phenol resin, etc. are mentioned. As petroleum tackifying resin, C5-type petroleum resin, C9-type petroleum resin, C5-type/C9-type copolymer-type petroleum resin, hydrogenated C5-type petroleum resin, hydrogenated C9-type petroleum resin, hydrogenated C5-type/C9-type petroleum resin. Total petroleum resin, dicyclopentadiene type petroleum resin, styrene type petroleum resin, etc. are mentioned. These tackifying resins may be used independently and may use 2 or more types together. Among these, terpene resins such as hydrogenated terpene resins and terpene phenols, hydrogenated rosin esters, disproportionated rosin esters, and rosins such as polymerized rosin, from the viewpoint of high compatibility with the acrylic triblock copolymer and exhibiting stable adhesion Tackifying resins, such as petroleum resins, such as petroleum resin, such as a C5/C9 type|system|group petroleum resin and aromatic petroleum resin, and styrene type resin, such as (alpha) methyl styrene polymer and a styrene/(alpha) methyl styrene copolymer, are preferably used. These may be used independently and may use 2 or more types together. In order for the softening point of tackifying resin to express high adhesive force, it is preferable that they are 50 degreeC or more and 150 degrees C or less.

As a compounding quantity of the tackifying resin in the composition for adhesive layer formation, from a viewpoint of improving the adhesive force of the adhesive layer 14, 0.5 mass part or more and 100 mass parts or less are preferable with respect to 100 mass parts of acrylic polymers mentioned above, , 1 mass part or more and 50 mass parts or less are more preferable.

<Ultraviolet absorbent>

It is preferable to contain a ultraviolet absorber as a composition for adhesive layer formation. By containing a ultraviolet absorber, the pigment|dye used for color tone adjustment of the heat resistant adhesive sheet 1, etc. can be protected from an ultraviolet-ray.

Examples of the ultraviolet absorber include a benzophenone-based compound, a benzotriazole-based compound, and a triazine-based compound. These ultraviolet absorbers may be used individually by 1 type, and may use 2 or more types together.

<Rust inhibitor>

It is preferable to contain a rust preventive as a composition for adhesive layer formation. By containing a rust preventive agent, when the adhesive layer 14 obtained contacts a metal electrode etc., the change of the transmittance|permeability by interaction of a metal and an additive, interaction of a metal, an adhesive, etc. can be reduced.

As the rust inhibitor, for example, an azole compound having a hydroxyl group, a triazole compound, a benzotriazole compound, a thiazole compound, a benzothiazole compound, an imidazole compound, a benzoimidazole compound, a phosphorus compound, an amine compound , nitrite-based compounds, surfactants, silane coupling agents, and the like, among these, benzotriazole-based rust inhibitors are preferable from the viewpoint of corrosion prevention performance. In addition, a rust inhibitor may be used individually by 1 type, and may use 2 or more types together.

Examples of the benzotriazole-based rust inhibitor include 1H benzotriazole, tolyl benzotriazole, 1-[N,N-bis(2-ethylhexyl)aminomethyl]benzotriazole, and 1-[N,N -bis(2-ethylhexyl)aminomethyl]methylbenzotriazole etc. are mentioned.

The compounding quantity of the rust preventive agent in the composition for adhesive layer formation is 0.1 mass % or more and 5 mass % or less with respect to the total mass of the solid content of the composition for adhesive layer formation from a viewpoint and adhesive viewpoint of obtaining the effect as a rust preventive mentioned above. It is preferable, and 0.3 mass % or more and 2 mass % or less are more preferable.

The thickness of the pressure-sensitive adhesive layer 14 is not particularly limited as long as the effect of the present invention is exhibited, for example, 3 μm or more is preferable, 10 μm or more is more preferable, and 20 μm or more is still more preferable, Moreover, 500 micrometers or less are preferable, 400 micrometers or less are more preferable, and 300 micrometers or less are still more preferable.

Moreover, when the adhesive layer 14 is comprised from the 1st adhesive layer 142, the 2nd adhesive layer 143, and the core material 141, the thickness of the core material 141 is preferably 2 micrometers or more, 5 ㎛ or more is more preferable, 50 ㎛ or less is preferable, and 45 ㎛ or less is more preferable. 1 micrometer or more is preferable, respectively, and, as for the thickness of the 1st adhesive layer 142 and the 2nd adhesive layer 143, 50 micrometers or less are preferable, respectively.

(Base Film (21))

As the base film 21, a plastic film having heat resistance can be appropriately selected and used. Examples of such plastic films include polyester films such as polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate (PEN), polyethylene films, polypropylene films, cellophane, diacetyl cellulose films, Triacetyl cellulose film, acetyl cellulose butyrate film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film , polyetheretherketone film, polyethersulfone film, polyetherimide film, polyimide film, fluororesin film, polyamide film, acrylic resin film, norbornene-based resin film, and plastic film such as cycloolefin resin film. can Among these, polyester films, polycarbonate films, polyimide films, norbornene-based resin films, cycloolefin resin films, etc. are preferable from the viewpoint of being preferably used as a substrate for optics and excellent transparency, and polyester films are preferred. It is more preferable that

In the base film 21, the layer which adds various functions to the surface of the above-mentioned plastic film may be formed. The base film 21 may have, for example, an easily bonding layer for strengthening adhesion with each layer on the surface on the side in contact with the functional layer 22 or the pressure-sensitive adhesive layer 14, the functional layer ( 22) A hard-coat layer may be formed in the surface on the side in contact with.

As thickness of the base film 21, 25 micrometers or more are preferable, 30 micrometers or more are more preferable, 35 micrometers or more are still more preferable, 250 micrometers or less are preferable, 225 micrometers or less are more preferable, 200 ㎛ or less is more preferable. When the above is considered, 25 micrometers or more and 250 micrometers or less are preferable, as for the thickness of the base film 21, 30 micrometers or more and 225 micrometers or less are more preferable, and their 35 micrometers or more and 200 micrometers or less are still more preferable.

In addition, in FIG. 1, although the base film 21 was shown as a single layer, the base film 21 is not necessarily limited to what is necessarily comprised by a single layer. The base film 21 may be comprised as a two-layer film in which the base film and the release agent layer were laminated|stacked, for example, and similarly to the release film 10, it may be comprised as a three-layer film.

<Oligomer encapsulation property>

The present inventors paid attention to being able to evaluate the degree of oligomer precipitation quantitatively by measuring the haze value of a heat resistant adhesive sheet with respect to oligomer precipitation evaluation which was only visual evaluation in the prior art. And the present inventors discovered that the damage of a transparent electrode layer and foreign material mixing could be prevented effectively by quantitative evaluation of oligomer precipitation by the measurement of the haze value of a heat resistant adhesive sheet.

In the heat-resistant pressure-sensitive adhesive sheet 1 according to the present embodiment, the oligomer deposited on the surface layer of the release film 10 turbids the release base material 11 (polyester film) to change the haze value of the release film 10 . . Therefore, in the present embodiment, by measuring the Δ haze value, which is the absolute value of the difference between the initial haze value of the release film 10 and the post-heating haze value after heating the release film 10 at 150° C. for 2 hours, the resin layer 12 The oligomer encapsulation property in this can be confirmed. However, in order to exclude the influence of the base film 21 being removed at the time of heating use (at the time of annealing treatment), the measurement of the initial haze value and the haze value after heating is carried out after the base film 21 is removed and the release film 10 and It is measured in the laminated body state of the adhesive layer 14.

In this embodiment, since the resin layer 12 is formed using the said composition for resin layer formation, the composition of (A)-(C) component is a suitable range for preventing oligomer precipitation from the peeling film 10. , and the Δ haze value can be made 0.15% or less. In addition, the initial stage haze value of the heat resistant adhesive sheet 1 is a haze value before heating the heat resistant adhesive sheet 1 at 150 degreeC for 2 hours. 0.1 % or less is preferable, as for (DELTA) haze value, 0.08 % or less is more preferable, 0.04 % or less is still more preferable.

In addition, in this embodiment, (DELTA) haze value is computable as follows. First, the initial haze value (%) of the heat resistant adhesive sheet 1 is measured based on JISK7105 using the haze meter (brand name: NDH2000, the Nippon Denshoku Industries Co., Ltd. make) (average value of N=5). Next, after hanging the heat resistant adhesive sheet 1 in a 150 degreeC dryer and heating for 2 hours, based on JISK7105, the haze value (%) after a heating is measured (average value of N=5). And let the absolute value of the value obtained by subtracting the initial haze value from the haze value after heating be the Δ haze value.

<Use>

The heat resistant adhesive sheet 1 which concerns on the said embodiment can be used suitably as a raw material film for bonding the transparent conductive film in a capacitive-type touch panel manufacturing process to a glass substrate etc., for example. When the heat-resistant pressure-sensitive adhesive sheet 1 is used for the production of a transparent conductive film, indium oxide, zinc oxide, tin oxide, indium-tin composite oxide, tin-antimony composite oxide, zinc-aluminum composite oxide, and indium-zinc composite A transparent conductive material such as an oxide is formed on the pressure-sensitive adhesive layer 14 to form a transparent conductive layer as the functional layer 22 . The thickness of the transparent conductive layer is preferably 4 nm or more, more preferably 5 nm or more, still more preferably 10 nm or more, and from the viewpoint of obtaining stable conductivity and obtaining sufficient transparency as a continuous thin film, and 800 nm or less is preferable, 500 nm or less is more preferable, and 100 nm or less is especially preferable.

In the heat-resistant pressure-sensitive adhesive sheet 1 according to the present embodiment, the Δ haze value, which is the absolute value of the difference between the initial haze value of the release film 10 and the post-heating haze value after heating at 150°C for 2 hours, is 0.15% or less, so transparent conductive Even in the case of performing annealing treatment by forming a layer, the change in haze value of the release film before and after the annealing treatment can be reduced, so that the heat-resistant pressure-sensitive adhesive sheet 1 with the transparent conductive layer is provided with the pressure-sensitive adhesive layer 14 It becomes possible to perform annealing treatment with it. In addition, in the annealing process of the transparent conductive film, since the release film 10 in the heat-resistant adhesive sheet 1 also serves as a protective sheet, the annealing treatment at a temperature of about 150 deg. can also be preferably used. Moreover, in the heat resistant adhesive sheet 1 which concerns on this embodiment, also in annealing treatment or other heat processing, the oligomer contained in a polyester film bleeds out, or precipitation of the oligomer-derived crystal|crystallization on the resin layer 12 surface. can be preferably suppressed, so it is possible to suppress mixing of micro-foreign substances derived from oligomers unsuitable as a touch panel and damage to the transparent electrode layer. In addition, the heat resistant adhesive sheet 1 which concerns on this embodiment is applicable also in the use which requires heat processing other than the manufacturing process of the touch panel using a transparent conductive film.

As described above, according to the above embodiment, the Δ haze value, which is the absolute value of the difference between the initial haze value of the peeling film 10 and the haze value after heating at 150°C for 2 hours, is 0.15% or less, so peeling before and after heat treatment The change of the haze value of the film 10 can be reduced, and it becomes possible to anneale with the heat resistant adhesive sheet 1 in which the transparent conductive layer was provided with the adhesive layer 14. As shown in FIG. A functional layer formed on the base film 21 by the release film 10 including the release base 11, the resin layer 12, and the release agent layer 13 (for example, the transparent conductive layer 22) Since the back side with respect to can be protected, when manufacturing a functional film, it becomes possible to omit the process of attaching and detaching the protective sheet which protects the back side of a functional layer. Therefore, the heat resistant adhesive sheet which can reduce the manufacturing cost of the functional film by manufacturing process shortening can be implement|achieved.

(Method for producing functional film)

Next, with reference to FIGS. 4A - 4C, the manufacturing method of the functional film which concerns on this embodiment is demonstrated. Here, although the example which manufactures a transparent conductive film is demonstrated as an example of a functional film, this invention is applicable to manufacture of various functional films other than a transparent conductive film.

4A-4C, the manufacturing method of the functional film which concerns on this embodiment is the resin layer 12, the peeling base material 11, the release agent layer 13, the adhesive layer 14, and the base film 21 ), a lamination process to obtain a laminate 3 in this order, and a conductive material is formed on the base film 21 to form a functional layer (eg, transparent conductive layer 22) to form a heat-resistant adhesive sheet The film-forming process of obtaining (1), and the heat processing process of heat-processing a heat resistant adhesive sheet are included.

In the lamination step, as shown in Fig. 4A, the resin layer 12 is formed by applying the composition for forming a resin layer on one main surface of the release substrate 11 by the Meyer bar coating method or the like, and the release substrate ( 11) The composition for forming a release agent layer is applied by the Meyer bar coat method or the like on the other main surface to form a release agent layer 13 to obtain a release film 10 . Next, as shown in FIG. 4B, after forming the pressure-sensitive adhesive layer 14 by applying the pressure-sensitive adhesive layer-forming composition on the release agent layer 13, the base film 21 is formed on the pressure-sensitive adhesive layer 14, It is set as the laminated body (3).

Next, in the film-forming process, as shown in FIG. 4C, the transparent conductive layer 22 (ITO: indium tin oxide film) is formed by sputtering, CVD, PVD, etc. on the base film 21, The heat resistant adhesive sheet 1 ) to get Next, in a heat treatment process, crystallization of ITO advances by the annealing process which heats the heat resistant adhesive sheet 1, and the transparent conductive layer 22 which is low resistance is manufactured. Here, since the release film 10 is formed on the back side of the outer surface of the transparent conductive layer 22, annealing treatment is performed while protecting the back side of the transparent conductive layer 22 without attaching another protective sheet or the like. Therefore, it is possible to achieve reduction in manufacturing cost by shortening the manufacturing process.

Example

Hereinafter, the present invention will be described in more detail based on Examples that have been implemented in order to clarify the effects of the present invention. In addition, this invention is not limited at all by the following Example and a comparative example.

<Calculation of Δ Haze Value>

Each of the heat-resistant adhesive sheets produced in the Example and the comparative example was cut out to 5 cm in width and length, and it was set as the test piece. The release film was peeled from this test piece, and the haze of this release film was measured (average value of N = 5) using a haze meter (brand name: NDH2000, manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS K 7105, and the initial haze value ( %). In addition, after fixing one corner of each test piece with a clip, hanging in a dryer at 150° C. and heating for 2 hours, peel the release film from this test piece, and measure the haze of this release film in accordance with JIS K 7105 (N = 5 average value) and set it as the haze value (%) after heating.

The absolute value of the value which subtracted the initial stage haze value from the haze value after heating was made into (DELTA) haze value, and the following reference|standard evaluated. Moreover, there is sufficiently little precipitation amount of the oligomer from the polyester film used as a peeling base material that (DELTA) haze value is 0.15 % or less, and the influence on a subsequent process can be reduced.

○ (Good): 0.15% or less

× (defective): 0.15% or more

(Example 1)

(Preparation process of the composition for resin layer formation)

(A) 100 parts by mass of bisphenol A epoxy compound (trade name: EPICLON H-360, manufactured by DIC: solid content concentration of 40 mass%, weight average molecular weight 25000), (B) polyester compound (trade name: Byron GK680, manufactured by Toyobo Corporation) : 19.0 mass parts of toluene solution (solid content concentration 30 mass %) of number average molecular weight 6000, glass transition temperature 10 degreeC), and (C) hexamethoxymethylmelamine (trade name: Cymel 303, solid content concentration 100 mass %, Nippon Cytec 11.4 parts by mass (manufactured by Industries, Ltd.) were mixed. The liquid mixture was diluted with a mixed solvent of toluene/methyl ethyl ketone (hereinafter, also referred to as "MEK") = 50 mass %/50 mass % so that solid content might be 3 mass %, and it stirred. Then, 2.9 mass parts of methanol solutions (solid content concentration of 50 mass %) of (D) p-toluenesulfonic acid were added, and the composition for resin layer formation was obtained.

(Manufacturing process of resin layer formation film)

The obtained composition for forming a resin layer was uniformly coated by the Meyer bar coat method on one surface of a biaxially stretched polyethylene terephthalate film (trade name: E5001, manufactured by Toyobo Corporation: 75 µm in thickness) as a base film. Then, the base film which apply|coated the composition for resin formation was passed through 150 degreeC oven for 20 second, the 150-nm-thick resin layer was formed, and the polyester film in which the resin layer was formed was obtained.

(Preparation process of the composition for release agent layer formation)

Next, 100 parts by mass of an addition reaction silicone resin (trade name: KS-774, manufactured by Shin-Etsu Chemical Industry Co., Ltd.) is diluted with a mixed solvent of toluene/MEK=50 mass%/50 mass% so that the solid content is 1.5 mass%, and stirred. did Then, 1 mass part of platinum catalysts (trade name: PL-50T, the Shin-Etsu Chemical Co., Ltd. make) was added, and the composition for release agent layer formation was obtained.

(Manufacturing process of release film)

Next, the composition for forming a release agent layer was uniformly coated on the surface opposite to the resin layer of the base film by the Meyer bar coat method. Then, the 150 degreeC oven was passed through the base film which apply|coated the composition for release agent layer formation for 20 second, the 150 nm-thick release agent layer was formed, and the release film was obtained.

(Preparation process of adhesive)

The adhesive composition which consists of the compounding ratio (solid ratio) of the following adhesive formulation 1 was melt|dissolved in toluene, and the coating liquid was prepared.

<Adhesive formulation 1>

100 parts by mass of acrylic copolymer (a copolymer of 95 parts by mass of butyl acrylate and 5 parts by mass of a copolymer of 2-hydroxyethyl acrylate, a weight average molecular weight (Mw) of 800,000)

- 15 mass parts of polyfunctional acrylate compound (tris(acryloxyethyl) isocyanurate; Toa Synthetic company make, brand name "Aronix M-315")

· Photoinitiator (a mixture of benzophenone and 1-hydroxycyclohexylphenyl ketone in a mass ratio of 1:1; manufactured by Chiba Specialty Chemicals, trade name "Irgacure 500") 1.5 parts by mass

- 3 parts by mass of a crosslinking agent (trimethylolpropane-modified tolylene diisocyanate; manufactured by Nippon Polyurethane, trade name "Colonate L")

-Silane coupling agent (3-glycidoxypropyl trimethoxysilane; Shin-Etsu Chemical Co., Ltd. make, brand name "KBM-403") 0.2 mass part

(Manufacturing process of heat-resistant adhesive sheet)

After apply|coating the prepared coating liquid with the knife type coater on the peeling layer of the peeling film prepared in the said process, it dried at 90 degreeC for 1 minute. Next, it bonded together with the annealing-treated polyester film (trade name: Merinex SA, 125 micrometers in thickness, made by Teijin DuPont) as a base film. The thickness of the adhesive layer after drying was adjusted to 25 micrometers. Next, 30 minutes after bonding the base film to the release film, ultraviolet (UV) light was irradiated from the release film side under conditions of an illuminance of 600 mW/cm 2 and a light quantity of 150 mJ/cm 2 (using an electrodeless lamp H valve manufactured by Fusion Corporation). Thus, a heat-resistant adhesive sheet was produced. The 23 degreeC storage elastic modulus of the obtained adhesive layer was 0.86 Mpa, and the gel fraction was 93 %.

(Example 2)

The composition for resin layer formation was (B) 22.22 parts by mass of the polyester compound, (C) 20 parts by mass of hexamethoxymethylmelamine, and (D) 3.3 parts by mass of the methanol solution of p-toluenesulfonic acid. It operated similarly to Example 1, and obtained the heat resistant adhesive sheet.

(Example 3)

The composition for resin layer formation was (B) 44.4 parts by mass of the polyester compound, (C) 13.3 parts by mass of hexamethoxymethylmelamine, and (D) 3.3 parts by mass of the methanol solution of p-toluenesulfonic acid. It carried out similarly to Example 1, and obtained the heat resistant adhesive sheet.

(Example 4)

The composition for forming a resin layer was changed to 100 parts by mass of (A) a bisphenol A epoxy compound (trade name: EPICLON EXA-123, manufactured by DIC: solid content concentration 30 mass%, weight average molecular weight 45000), (B) polyester The same as in Example 1 except that the compound was 14.3 parts by mass, (C) hexamethoxymethylmelamine was 8.6 parts by mass, and (D) the methanol solution of p-toluenesulfonic acid (solid content concentration: 50 mass%) was 2.1 parts by mass. to obtain a heat-resistant adhesive sheet.

(Example 5)

The composition for forming a resin layer was (B) a polyester compound (trade name: Byron GK810, manufactured by Toyobo Corporation: number average molecular weight 6000, glass transition temperature 46°C) in toluene solution (solid content concentration: 30 mass%) except for changing It carried out similarly to Example 1, and obtained the heat resistant adhesive sheet.

(Example 6)

A heat-resistant adhesive sheet was produced in the same manner as in Example 1 except that the formulation of the pressure-sensitive adhesive composition was changed to the pressure-sensitive adhesive formulation 2 below, the drying treatment was 120° C. for 1 minute, and UV irradiation was not performed. The 23 degreeC storage elastic modulus of an adhesive layer was 0.61 Mpa, and the gel fraction was 88 %.

<Adhesive formulation 2>

100 parts by mass of acrylic copolymer (80 parts by mass of butyl acrylate, 10 parts by mass of methyl methacrylate and 10 parts by mass of 2-hydroxyethyl methacrylate, 800,000 weight average molecular weights)

· Crosslinking agent 1 (tolylene diisocyanate type (TDI type) crosslinking agent; manufactured by Toyo Ink Co., Ltd., trade name "Oribine BHS8515") 2.6 parts by mass

·Crosslinking agent 2 (metal chelate type crosslinking agent; manufactured by Soken Chemical Co., Ltd., trade name "M-5A") 0.25 parts by mass

(Example 7)

The adhesive sheet was manufactured like Example 1 except having changed the compounding|blending of an adhesive composition into the following adhesive formulation 3, and not having performed ultraviolet irradiation. The 23 degreeC storage elastic modulus of an adhesive layer was 0.58 Mpa, and the gel fraction was 75 %.

<Adhesive formulation 3>

100 parts by mass of acrylic copolymer (94.9 parts by mass of butyl acrylate, 5 parts by mass of 2-hydroxyethyl acrylate and 0.1 parts by mass of acrylic acid, weight average molecular weight (Mw) 1.8 million)

- 3 parts by mass of a crosslinking agent (trimethylolpropane-modified tolylene diisocyanate; manufactured by Nippon Polyurethane, trade name "Colonate L")

(Comparative Example 1)

Except not having formed the resin layer in the peeling film, it carried out similarly to Example 1, and obtained the adhesive sheet.

(Comparative Example 2)

The composition for forming a resin layer was carried out except that (B) no polyester compound was used, (C) hexamethoxymethylmelamine was 10 parts by mass, and (D) p-toluenesulfonic acid methanol solution was 2.5 parts by mass. It carried out similarly to Example 1, and obtained the adhesive sheet.

(Comparative Example 3)

The composition for resin layer formation was (B) 222.2 parts by mass of the polyester compound, (C) 26.7 parts by mass of hexamethoxymethylmelamine, and (D) 6.7 parts by mass of the methanol solution of p-toluenesulfonic acid. It carried out similarly to Example 1, and obtained the adhesive sheet.

As can be seen from Table 1, in the pressure-sensitive adhesive sheets of Examples 1 to 7, Δhaze, which is the amount of change in haze after heat treatment, is very small, and the oligomer component does not precipitate on the outer surface of the release film, and the oligomer encapsulation property is not It can be seen that good Accordingly, in the pressure-sensitive adhesive sheets of Examples 1 to 7, since oligomers do not precipitate on the outer surface of the release film even when subjected to heat treatment, the functional layer is not damaged by oligomers even when the pressure-sensitive adhesive sheet is wound. It is possible to heat-process without using the protective film for oligomer sealing.

On the other hand, in Comparative Example 1 in which the resin layer was not formed, it can be seen that the Δ haze was very large, there was precipitation of a large amount of oligomers, and the encapsulation properties of the oligomers were remarkably inferior. Moreover, even when the resin layer was formed, in the comparative example 2 which does not mix|blend a polyester compound, and the comparative example 3 with much content of a polyester compound, Δ haze became large and the oligomer sealing property was insufficient. Accordingly, in the pressure-sensitive adhesive sheets of Comparative Examples 1 to 3, when the pressure-sensitive adhesive sheet is wound after heat treatment such as annealing treatment, the oligomer component deposited on the outer surface of the release film by the heat treatment is electrodeposited on the surface of the functional layer side, , it becomes a factor that deteriorates the electrical properties and optical properties of the functional layer.

1, 2: Heat-resistant adhesive sheet
3: laminate
10: release film
11: peeling base material
12: resin layer
13: release agent layer
14: adhesive layer
141: heart
142: first pressure-sensitive adhesive layer
143: second pressure-sensitive adhesive layer
21: base film
22: functional layer

Claims (10)

A release film comprising a release substrate made of a polyester film, a resin layer formed on one main surface of the release substrate, and a release agent layer formed on the other main surface of the release substrate;
a pressure-sensitive adhesive layer formed on the release agent layer;
and a base film formed on the pressure-sensitive adhesive layer,
The heat-resistant adhesive sheet, characterized in that the Δhaze value, which is the absolute value of the difference between the initial haze value of the release film and the haze value after heating at 150°C for 2 hours, is 0.15% or less. The method of claim 1,
The heat-resistant adhesive sheet in which the said release agent layer hardens|cures addition-reaction type silicone. The method of claim 1,
The said resin layer hardens|cures the composition for resin layer formation containing (A) a bisphenol A epoxy compound, (B) a polyester compound, and (C) a polyfunctional amino compound, The heat-resistant adhesive sheet formed. 4. The method of claim 3,
In the composition for forming a resin layer, the content of the bisphenol A epoxy compound is 50 mass% or more and 80 mass% or less, the content of the polyester compound is 5 mass% or more and 30 mass% or less, and the polyfunctional amino compound is The heat-resistant adhesive sheet whose content is 10 mass % or more and 40 mass % or less. 4. The method of claim 3,
The heat-resistant adhesive sheet whose weight average molecular weights of the said bisphenol A epoxy compound are 10000 or more and 50000 or less. 4. The method of claim 3,
The heat-resistant adhesive sheet whose glass transition temperature (Tg) of the said polyester compound is 0 degreeC or more and 50 degrees C or less. 4. The method of claim 3,
The heat-resistant adhesive sheet in which the said resin layer applied the solution of the said composition for resin layer formation on the said base film, and made the coating layer formed by heating the cured film. The method of claim 1,
The heat-resistant adhesive sheet whose film thickness of the said resin layer is 50 nm or more and 500 nm or less. On the release agent layer of the release film comprising a release substrate made of a polyester film, a resin layer formed on one main surface of the release substrate, and a release agent layer formed on the other main surface of the release substrate, an adhesive layer and a substrate A lamination step of obtaining a heat-resistant adhesive sheet in which the films are laminated in this order, and the Δhaze value, which is the absolute value of the difference between the initial haze value of the release film and the haze value after heating at 150°C for 2 hours, is 0.15% or less;
A film forming step of forming a conductive material as a functional layer on the base film of the heat-resistant pressure-sensitive adhesive sheet;
A method for producing a functional film, comprising a heat treatment step of heat-treating the heat-resistant pressure-sensitive adhesive sheet on which the functional layer is formed. 10. The method of claim 9,
The manufacturing method of the functional film whose said functional layer is a transparent conductive layer.

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