JPH1124081A - Optical element and laminated transfer sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical element which has various superior characteristics that the optical element needs to have, i.e., mechanical strength and chemical resistance and the laminated transfer sheet used suitably for its manufacture. SOLUTION: This optical element which is formed including a transparent substrate 1, a radiation cross-linked adhesive layer 2 laminated on the transparent substrate 1, and a laminated body 3 formed on the adhesive layer 2 by being transferred from a temporary carrier 4 so that the laminated body 3 has a transparent conductive layer 31 formed on the adhesive layer 2 in contact and a resin layer 32 laminated on the transparent conductive layer 31 has the resin layer 32 formed of a coating containing polyimide calcined before the laminated body 3 is transferred from the temporary carrier 4 to the adhesive layer 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an optical element and a laminate transfer sheet. More specifically, an optical element effectively used for various display devices such as a liquid crystal display,
And a laminate transfer sheet suitable for manufacturing the optical element. The polyimide resin layer in the optical element and the laminate transfer sheet is effectively used, for example, for forming a liquid crystal alignment film.

[0002]

2. Description of the Related Art Conventionally, polymethyl methacrylate,
Polyethylene terephthalate, on a transparent substrate made of a plastic such as polyethylene naphthalate, a transparent conductive layer that is releasably laminated on a temporary carrier is transferred via an adhesive, and includes a transparent substrate and a transparent conductive layer. A method for manufacturing an optical element consisting of Such a transparent conductive layer is usually made of an ITO (indium-tin-oxide) film, and has a light transmittance of usually 70% or more. Further, the light transmittance of the above transparent substrate is usually 70% or more. As such an optical element and a laminate transfer sheet, for example, JP-A-60-231396 discloses
A transfer-type laminate in which an ITO layer is provided on a support (temporary support) in a detachable state is disclosed. This publication states that an IT support is provided on a support made of Teflon film.
An O layer is deposited, and then a heat treatment is performed in an oven at 300 ° C. to reduce the resistance of the ITO layer. Using a transfer-type laminate formed, the ITO layer is formed on a polymethyl methacrylate substrate via an acrylic adhesive. The method of transferring onto the image is exemplified. It is also suggested that an aromatic polyimide can be used as a support (temporary support). Also, JP-A-59-204542 discloses that after an ITO layer is deposited on a heat-resistant substrate subjected to a release treatment, the surface of a polarizing plate (polyethylene terephthalate (polyethylene terephthalate) A method of transferring an ITO layer to a (PET) film) is disclosed. This polarizing plate has two P
It has a structure in which a polarizer is stuck between ET films. Also, JP-A-58-177345 discloses that an ITO layer is sputtered on a release treatment surface of a polyester film having a silicone release treatment surface, and the ITO layer and the polyvinyl butyral sheet are thermocompression-bonded to each other. A method for transferring an ITO layer onto a butyral sheet surface is disclosed. JP-A-59-151705 discloses that a layer of an ITO vapor-deposited film is formed on a temporary support such as a Teflon sheet, and the ITO layer is formed through a thermosetting or photocurable adhesive. And a method of transferring to the surface of a plastic transparent substrate. Further, Japanese Patent Application Laid-Open No.
Japanese Patent No. 2517 discloses an IT device formed on a support (temporary support) via an adhesive layer whose adhesive force changes by light irradiation.
There is disclosed a method in which an O layer is brought into close contact with a substrate, light is irradiated onto a predetermined pattern through a mask that transmits or blocks light, and the patterned ITO layer is transferred to the substrate. It also discloses that a polyimide film can be used for the temporary support, and that a composition comprising an acrylate monomer can be used as an adhesive whose adhesive force changes by light irradiation. Also, JP-A-7-80980 discloses that
IT on a substrate consisting of a film with low surface energy
A transparent conductive transfer sheet in which an O layer and an adhesive layer are laminated in this order is disclosed. As a specific example of a film having a low surface energy, it is disclosed that oriented polypropylene can be used for the adhesive layer and that the film has low surface energy.

In the above-described series of transfer laminates and transfer methods, an ITO layer is directly laminated on a temporary carrier, and a resin layer (exfoliation) transferred together with the ITO layer is provided between the temporary carrier and the ITO layer. (A resin layer that is not a layer) is not provided.
On the other hand, a method of transferring a laminate composed of a transparent conductive layer such as ITO and a resin layer adhered on the transparent conductive layer has been proposed.
For example, it is disclosed in the following literature. JP 2
Japanese Patent Publication No. 1740011 discloses a temporary support (release sheet).
A resin film is laminated on the substrate, an ITO layer is laminated on the resin film, a heat-adhesive adhesive layer is laminated on the ITO layer, a transfer sheet is formed, and the transfer sheet is heated on a glass substrate. A method is disclosed in which a laminate composed of an ITO layer and a resin film is transferred via an adhesive layer while pressing and bonding.
It is disclosed that a synthetic resin film of polyethylene, polypropylene, polyester, or the like can be used as the temporary support, and that a release treatment can be performed if necessary. It is disclosed that the resin film functions as a protective film for the ITO layer and is preferably selected from the group consisting of a cellulose resin, an acrylic resin, and a nylon resin. Japanese Patent Application Laid-Open No. 8-254690 discloses a lamination comprising a water-soluble release film formed on a temporary support and an ITO layer formed by sputtering on the water-soluble release film. A method of transferring a body to a transparent substrate via a layer of a thermal transfer adhesive is disclosed. It is disclosed that a polyethylene terephthalate film or the like can be used as a temporary support, and that a polyester resin or an acrylic resin can be used as a thermal transfer adhesive. It also discloses that a polymer such as polyvinyl alcohol can be used as the water-soluble release film, and that the release film is removed by washing after transfer of the laminate.

[0004]

However, the resin layer of the laminate disclosed in the latter two documents has only the function of easy transfer (peeling) from the temporary support and the function of protecting the ITO layer. Is just what is expected. For example, in an optical element used for manufacturing a liquid crystal display, a liquid crystal alignment film is formed on the surface of a transparent conductive layer. In order for the resin layer to function as a layer for forming the liquid crystal alignment film, the liquid crystal must be oriented in a certain direction. In addition to generating an appropriate pretilt angle, characteristics such as high mechanical strength and high chemical resistance are required. For example, in order to provide an orientation function, it is necessary to rub the resin layer with a cloth such as cotton, nylon, rayon or the like having hair of several mm wound around a roll. When used as an alignment film, the thickness of the resin layer is usually about 0.05 to 0.5 μm, and if the mechanical strength is insufficient, breakage occurs. Further, in order to remove abrasion powder of the resin layer due to rubbing, ultrasonic cleaning is usually performed in water or an organic solvent. Therefore, if the chemical resistance is insufficient, the alignment film is eroded. On the other hand, the IT
The method of providing such a resin layer on the ITO layer after transferring only the O layer should be avoided from the following viewpoints. That is, the formation of such a resin layer requires a baking treatment at a temperature of 80 ° C. or higher, and a film such as polymethyl methacrylate or polyethylene terephthalate useful as a transparent substrate can withstand such a heat treatment. And cannot be deformed. The present invention has been made in view of the above-described problems, and is suitably used for an optical element excellent in all of the characteristics required as an optical element, that is, mechanical strength, chemical resistance, and the like, and for manufacturing the optical element. It is an object to provide a laminate transfer sheet.

[0005]

According to the present invention, there is provided an optical element and a laminate transfer sheet having the following features. [1] A transparent substrate, a radiation-crosslinked adhesive layer formed on the transparent substrate, and a laminate formed on the adhesive layer by transferring from a temporary carrier. In the optical element having a transparent conductive layer formed in close contact with the adhesive layer and a resin layer formed by being laminated on the transparent conductive layer, the resin layer includes An optical element comprising a polyimide-containing coating film that has been subjected to a baking treatment before transfer from the temporary support of the laminate to the adhesive layer. [2] The optical element according to [1], wherein the adhesive contains an acrylate compound containing a polyfunctional (meth) acrylate monomer as an adhesive component thereof. [3] A laminated body transfer sheet used for manufacturing an optical element, wherein the resin layer is composed of a temporary support and a coating film containing a polyimide which has been subjected to a baking treatment and is releasably provided on the temporary support. And, while comprising a transparent conductive layer formed by lamination on the resin layer, and a radiation-crosslinkable adhesive layer formed by lamination on the transparent conductive layer, the temporary carrier, The resin layer has a polymer surface made of a heat-resistant polymer that does not contain fluorine atoms and silicon atoms and has a glass transition temperature (Tg) higher than the firing temperature of the resin layer. A laminate transfer sheet comprising a coating film that has been applied to the polymer surface of the carrier and then subjected to a baking treatment. [4] The laminate transfer sheet according to [3], wherein the resin layer has a firing temperature of 80 to 300 ° C.

[0006]

Embodiments of the present invention will be specifically described below with reference to the drawings. I. Optical Element As shown in FIG. 1, the optical element of the present invention comprises a transparent substrate 1
And a radiation-crosslinked adhesive layer 2 formed on the transparent substrate 1 and a laminate 3 formed on the adhesive layer 2 by transfer from the temporary carrier 4. It is configured. The laminate 3 has a transparent conductive layer 31 formed in close contact with the adhesive layer 2 and a resin layer 32 formed by being laminated on the transparent conductive layer 31. The layer 32 is made of a predetermined coating containing polyimide, which has been subjected to a baking treatment before the transfer.

The resin layer used in the present invention is a coating film (polyimide resin layer) containing polyimide which satisfies the characteristics (high mechanical strength and chemical resistance) required for forming a liquid crystal alignment film as described above. ). Further, as described above, the polyimide resin layer is subjected to a baking treatment before the transfer from the temporary support. Therefore, there is no possibility that the transparent substrate is damaged by heating as described above. Further, the baking treatment of the polyimide resin layer acts to weaken the adhesive force at the interface (release surface) between the temporary support and the polyimide resin layer. Here, the “baking treatment” means a heating treatment for removing a residual solvent or completing a curing reaction in the case of a thermosetting type. In the case of forming a liquid crystal alignment film, a heat treatment as a process for generating a pretilt angle is also included. Such a baking treatment also acts to weaken the interfacial adhesion between the polyimide resin layer and the temporary carrier. Although the reason is not clear, it is considered that the increase in the internal cohesion of the resin layer due to the baking treatment is one of the causes.

On the other hand, when the adhesive layer for transfer is made of an adhesive which has been subjected to radiation crosslinking, the interfacial adhesion (adhesion) between the adhesive layer and the laminate can be effectively increased. Therefore, in combination with the effect of the baking treatment of the polyimide resin layer, peeling of the laminate from the temporary support, that is, transfer of the laminate to the transparent substrate becomes easy. In addition, particularly a fluorine-based resin is applied to the release surface of the temporary support (the surface to which the polyimide resin layer is applied).
Since there is no need to provide a release treatment layer of a silicone resin or the like, coating defects caused by repelling or the like at the time of applying the polyimide resin layer can be effectively prevented. Therefore, the resin layer can be easily formed into a coating film, and a uniform and smooth polyimide resin layer surface can be formed after the transfer. Also,
There is no inconvenience that the surface of the resin layer after transfer is contaminated with the release agent.

Hereinafter, the present invention will be specifically described for each component. 1. Transparent substrate As the transparent substrate used in the present invention, high transparency,
A flexible plastic film is preferred. Specific examples of such plastics include polyester resins such as polyethylene terephthalate and polyethylene naphthalate; acrylic resins such as polymethyl methacrylate and modified polymethyl methacrylate; fluororesins such as polyvinylidene fluoride and acrylic-modified polyvinylidene fluoride; polycarbonate resins Vinyl chloride resins such as vinyl chloride copolymers; and polyarylates. These may be either alone or a mixture thereof. Further, a multilayer film including a plurality of such plastic films may be used. The transparent substrate can be formed by performing a baking treatment on a polyimide resin layer described later, forming a transparent conductive layer on the resin layer, and then laminating the transparent conductive layer on the transparent conductive layer.
Since it can be formed in this manner, a plastic film having relatively low heat resistance can be used as the transparent substrate.

[0010] Among the above plastics, polymethyl methacrylate is particularly suitable for producing optical elements for liquid crystal displays because of its excellent transparency and relatively small retardation value. The transmittance of the transparent substrate is preferably 70% or more, more preferably 80% or more. In addition, the "light transmittance" in the present invention means a light transmittance measured using a self-recording spectrophotometer "Model: U-4000" manufactured by Hitachi, Ltd. using light of 550 nm. The thickness of the transparent substrate is preferably from 10 to 1,000 μm. Further, as long as the effects of the present invention are not impaired, additives such as an ultraviolet absorbent, a moisture absorbent, a coloring agent, a fluorescent substance, and a phosphorescent substance may be contained in the transparent base material.
Further, a prism film can be used as the transparent substrate. 2. Adhesive layer In the present invention, the adhesive layer is used for bonding the transparent conductive layer and the transparent substrate. This adhesive layer can be formed, for example, by coating a crosslinkable liquid containing a crosslinkable monomer or oligomer on the transparent conductive layer and crosslinking the transparent conductive layer. Since the viscosity of the liquid containing the monomer or oligomer is sufficiently low, an adhesive layer having a uniform thickness can be formed. The viscosity (25 ° C.) of the crosslinkable liquid is preferably from 1 to 100,000 centipoise, more preferably from 5 to 80,000 centipoise, and most preferably from 10 to 50,000 centipoise. If the viscosity is less than 1 centipoise, a layer having a sufficient thickness cannot be formed, and the adhesiveness may be reduced. Conversely, if the viscosity exceeds 100,000 centipoise, a layer having a uniform thickness may not be formed. There is. The thickness of the adhesive layer is preferably from 1 to 100 μm.

The adhesion of the transparent conductive layer and the transparent substrate by the adhesive layer (that is, the transfer of the laminate composed of the transparent conductive layer and the polyimide resin layer from the temporary support) is performed by the crosslinking formed on the transparent conductive layer. The method can be carried out by laminating and adhering a transparent substrate to the surface of the previous adhesive layer, irradiating the adhesive with radiation and crosslinking, and then removing and removing the temporary carrier. Lamination and adhesion between the adhesive layer and the transparent substrate can be easily performed by pressing the transparent substrate. The peeling direction of the temporary support is not particularly limited, but it is preferable that the peeling is performed such that the angle between the polyimide resin layer and the temporary support is 5 to 180 degrees.

After forming an adhesive layer before crosslinking on the surface of the transparent substrate, the adhesive layer is brought into close contact with the laminated body composed of the transparent conductive layer and the polyimide resin layer after firing to crosslink the adhesive. You can also. In this case, after the primer is applied to the surface of the transparent substrate, a crosslinkable liquid can be applied.

[0013] The crosslinking treatment of the adhesive layer can be performed by irradiating the transparent substrate with radiation. As the radiation, ultraviolet rays, electron beams, visible rays, far infrared rays, and the like can be used. The irradiation amount can be appropriately determined so that the adhesive layer is sufficiently crosslinked. For example, in the case of ultraviolet rays, 1 to 10 J / cm ² is preferable. As the monomer or oligomer contained in the crosslinkable liquid forming the adhesive layer, compounds such as (meth) acrylate compounds and epoxy compounds can be used. The (meth) acrylate compound preferably comprises a polyfunctional acrylate compound. Thereby, the crosslink density of the adhesive layer after polymerization can be improved, the dimensional stability over time can be increased, and peeling due to shrinkage or expansion of the adhesive layer can be effectively prevented. Also,
Additives can be included in the crosslinkable liquid, if desired. For example, a polymerization initiator can be included to increase the reactivity. In addition, a coupling agent such as a silane coupling agent can be included to enhance the adhesiveness. The coupling agent is a crosslinking compound 1
It is preferable to add 0.1 to 10 parts by weight to 00 parts by weight. Also, in order to increase the refractive index of the adhesive layer,
Inorganic colloid particles such as antimony pentoxide and zirconia may be included. As other additives, as long as the effects of the present invention are not impaired, conductive particles, surfactants, ultraviolet absorbers, antioxidants, fungicides, rust inhibitors, moisture absorbers, coloring agents such as fluorescent paints, Additives such as phosphorescent substances can also be used.

3. Laminate The laminate used in the present invention has a transparent conductive layer and a resin layer as described above. (1) Transparent conductive layer The transparent conductive layer used in the present invention is preferably formed by applying a baking treatment to a polyimide resin layer and then coating the polyimide resin layer on the resin layer. As the transparent conductive layer, ITO, which is widely used as a transparent electrode of a liquid crystal display, is used.
(Indium tin oxide) film or the like can be used. The thickness of the transparent conductive layer is 0.01 to 1,000.
The surface resistance is preferably 500 Ω / □ or less, more preferably 1 to 200 Ω / □. Also,
The light transmittance is preferably 70% or more, more preferably 80% or more. The ITO film can be formed by general-purpose coating means such as vapor deposition, sputtering, and application of a paste. Thereby, an ITO film adhered to the polyimide resin layer can be obtained. In addition, as long as the effects of the present invention are not impaired, after providing a primer layer on the polyimide resin layer, a transparent conductive layer can be coated on the primer layer.

(2) Resin Layer The resin layer used in the present invention comprises a polyimide-containing coating film (polyimide resin layer) which has been subjected to a baking treatment before transfer. As the polyimide resin layer, it is preferable to use a coating film of the following [a] or [b]. [A] a coating film formed from a coating material comprising an organic solvent and a soluble polyimide dissolved in the organic solvent,
[B] A cured coating film formed from a paint containing a thermosetting polyimide resin. Here, the thermosetting polyimide resin also includes what is generally called “thermopolymerized polyimide resin”. This resin layer can be formed by directly coating the above-mentioned paint containing polyimide on the surface of a polymer made of a heat-resistant polymer of a temporary support described later.

In order to transfer the laminate to the transparent substrate more effectively, it is preferable to use the following [I] and / or [II]. [I] The adhesive layer contains an adhesive component composed of an acrylate compound containing a polyfunctional (meth) acrylate monomer. [II] The firing temperature of the polyimide resin layer is set in the range of 80 to 300 ° C. The adhesive layer in the case of the above [I] preferably contains a polymerization initiator in order to promote crosslinking of the adhesive component. Further, a more preferable range of the firing temperature of [II] is 140 to 290 ° C.,
80 ° C. is most preferred.

Specific examples of the polyimide include soluble polyimide having a tetraphenylthiophene skeleton, cyclobutanetetracarboxylic dianhydride / aromatic diamine-based polyimide, vapor-deposited polymerization polyimide, aromatic tetracarboxylic dianhydride / aromatic diamine / Contains silicone diamine-based polyimide, aromatic tetracarboxylic dianhydride / aliphatic diamine-based polyimide, fluorine-containing polyimide, wholly aromatic polyimide using long-chain aromatic diamine, organic electrolyte-added polyimide, silylated polyimide, and polyamic acid A polyimide formed by polymerizing (curing) a precursor can be used.

As the solvent contained in the coating material, a polar solvent such as N-methylpyrrolidone and γ-butyrolactone can be suitably used. For coating of paint, usual coating means, for example, spin coating,
Die coating, bar coating, vapor deposition coating and the like can be used. Further, as long as the effects of the present invention are not impaired, the polyimide resin layer may be formed of a plurality of layers. Further, in the polyimide resin layer, as long as the effect of the present invention is not impaired, an ultraviolet absorber,
Additives such as a hygroscopic agent, a coloring agent, a fluorescent substance, and a phosphorescent substance may be contained.

4. Temporary Carrier As the temporary carrier used when transferring the laminate to the transparent substrate, a temporary carrier used in a later-described laminate transfer sheet can be suitably used.

[5] Manufacturing Method The optical element of the present invention can be suitably manufactured using a laminate described below.

II. Laminate Transfer Sheet The laminate transfer sheet of the present invention is suitably used for producing the optical element. The reason is as follows. That is, the ITO layer itself can be easily peeled from various polymer films, and can be easily peeled from the temporary support without the need to separately provide a release treatment layer. However, when an optical element having a laminate composed of a transparent conductive layer such as ITO and a resin layer laminated on the surface of the conductive layer is formed by a transfer method, the resin layer can be peeled off on the surface of the temporary carrier. Temporary bonding is required, and a release treatment layer is usually required on the resin layer. In such a method, productivity is reduced by the amount of steps for providing the release treatment layer. In addition, there is a risk of contamination of the resin layer surface by the release agent. Therefore, it is preferable to manufacture an optical element using the laminate transfer sheet of the present invention which has solved the above-mentioned problem.

As shown in FIG. 2, the laminate transfer sheet according to the present invention comprises a predetermined temporary carrier 4 and a polyimide resin layer 32.
, The transparent conductive layer 31 and the adhesive layer 2 are sequentially laminated. The laminate transfer sheet of the present invention does not include a release treatment material layer on the release surface (temporary adhesion surface) of the temporary support to which the polyimide resin layer is temporarily bonded, and the polymer of the temporary support has a molecular structure. Contains no fluorine atoms and no silicon atoms. Therefore, coating defects such as repelling at the time of applying the polyimide resin layer can be effectively prevented, and the polyimide resin layer can be easily formed into a coating film. Further, since the temporary bonding surface of the temporary support has a surface made of a heat-resistant polymer having a Tg exceeding the firing temperature of the polyimide resin layer, thermal deformation (thermal shrinkage, etc.) of the temporary support occurs in the firing process. Nothing. The Tg of the heat-resistant polymer is determined so as to exceed the baking temperature of the resin layer.
0 ° C. is more preferred.

Hereinafter, the present invention will be specifically described for each component.

1. Temporary Support The temporary support used in the laminate transfer sheet of the present invention is, as described above, a heat-resistant polymer that does not contain a fluorine atom and a silicon atom in the molecule and has a Tg exceeding the firing temperature of the polyimide resin layer. Having a polymer surface consisting of Examples of such a temporary support include [1] a polymer support made of the above heat-resistant polymer, and [2] a multilayered support having a polymer layer made of the above heat-resistant polymer on the surface of the support. it can. The thickness of the entire temporary support is preferably from 10 to 3,000 μm, and the thickness of the polymer layer in the case of the above [2] is preferably from 0.1 to 100 μm.

Specific examples of the above-mentioned heat-resistant polymer include PI (polyimide), PEI (polyetherimide), PAR (polyarylate), and PEEK (polyetheretherketone). In addition, as the material of the support in the above [2], a material that is not thermally damaged even during the baking treatment of the polyimide resin layer is selected. For example, glass, ceramic, metal, or a heat-resistant polymer as described above. As long as the effects of the present invention are not impaired, a temporary support (eg, PET, PEN) used in a normal transfer method is used.
(Polyether nitrile) and the like can also be used.

2. Polyimide resin layer As the polyimide resin layer used in the present invention, those used in the above-described optical element can be used. That is, as described above, a coating containing polyimide can be formed from a coating film that has been subjected to a baking treatment after being applied to the polymer surface of the temporary support.

3. Transparent conductive layer The same layer as that used for the above-described optical element can be used.

4. Adhesive layer The same layer as that used for the above-mentioned optical element can be used.

5. Manufacturing Method The laminate transfer sheet of the present invention can be manufactured, for example, as follows. First, a polyimide-containing paint is coated on the temporary support to form a resin layer before firing having a uniform thickness. Next, a baking treatment is performed on the resin layer to form a polyimide resin layer. Subsequently, a transparent conductive layer is formed on the resin layer, and a laminate including the polyimide resin layer and the transparent conductive layer formed on the temporary carrier is obtained. Finally, a radiation-crosslinkable adhesive is dropped on the transparent conductive layer of the laminate, and the release film is laminated while being pressed, and a precursor of the adhesive is formed between the polyimide resin layer and the transparent substrate. Form a layer. Thereby, a laminated body transfer sheet including a release film laminated on the precursor layer of the adhesive can be obtained. As the release film, those used for ordinary adhesives can be used. For example, a polyethylene terephthalate film having a silicone-treated layer, a low molecular weight or ultra-low molecular weight polyethylene film, and the like.

6. Application to an optical element To produce an optical element using the laminate transfer sheet of the present invention, first, remove the release film, and laminate while pressing the transparent substrate on the adhesive precursor layer, continue,
Irradiate radiation from above the transparent substrate to crosslink the adhesive,
The laminate and the transparent substrate are bonded via a radiation-crosslinked adhesive layer. Finally, the temporary carrier is removed from the polyimide resin layer, and the transfer of the laminate including the transparent conductive layer and the polyimide resin layer to the transparent substrate is completed. Further, using a transparent substrate instead of the release film, a laminate transfer sheet, a precursor of an optical element consisting of a transparent substrate laminated on the precursor layer of the adhesive, to form an adhesive, After the crosslinking, the temporary support may be removed to complete the transfer of the laminate. Such a precursor of the optical element can be considered as another embodiment of the laminated body transfer sheet including the transparent substrate preliminarily laminated. Furthermore, as long as the effects of the present invention are not impaired, the transparent conductive layer can be arranged in a pattern according to the shapes and dimensions of, for example, pixels, electrodes, color filter layers and the like of the liquid crystal display device. For example, in the laminate transfer sheet of the present invention, an ITO layer arranged in a pattern on a polyimide resin layer can be transferred onto a transparent substrate via an adhesive layer. The patterned ITO layer can be formed into a pattern by, for example, forming an ITO layer formed of a continuous film on a polyimide resin layer and then performing an etching process to remove unnecessary portions.

[0031]

EXAMPLES The present invention will be described more specifically with reference to the following examples.

Example 1 On a polyimide film "Tapton made by Toray DuPont Kapton: 50 μm thickness" as a temporary carrier, a soluble polyimide solution "Product No. AL3046 made by Nippon Synthetic Rubber Co., Ltd .: Solvent γ" -Butyrolactone 'was spin-coated to form a resin layer before firing having a uniform thickness. Next, the resin layer was baked at 180 ° C. for 1 hour to form a polyimide resin layer. The thickness of the polyimide resin layer was about 100 nm. Subsequently, a sputtering target having a composition of indium oxide / tin oxide = 90/10 (weight ratio) was formed on the resin layer by using ITO.
A film is formed to a thickness of about 100 nm by a sputtering method, and a polyimide resin layer-IT formed on a temporary support is formed.
A laminate composed of an O film was obtained. Subsequently, on top of the ITO film of this laminate, bidantin hexaacrylate /
1,6-hexanediol diacrylate / Irgacure 651 = 70/29/1 [weight ratio]
A radiation-crosslinkable adhesive having a composition of (1) was dropped, and a transparent substrate (polymethyl methacrylate film) was laminated under pressure to form a layer of an adhesive precursor between the polyimide resin layer and the transparent substrate. . In addition, Irgacure 651
It was added as a polymerization initiator. Further, ultraviolet rays are irradiated from above the transparent substrate of the transfer sheet at an irradiation amount of about 3.5 J / cm ² to crosslink the adhesive, and the laminate and the transparent substrate are bonded together by radiation crosslinking. Adhered through a layer of agent. Lastly, the temporary carrier was removed from the polyimide resin layer, and the transfer of the laminate composed of the ITO film and the polyimide resin layer to the transparent substrate was completed. Through these series of operations, the optical element of the present invention could be easily formed. That is, the transparent substrate was not thermally damaged, and the surface of the polyimide resin layer was uniform and smooth. The surface of the resin layer after the transfer was not contaminated with the release agent. Furthermore, since the resin layer contains polyimide and has been subjected to a sufficient baking treatment, the resin layer has satisfied the required characteristics as a layer for forming a liquid crystal alignment film. That is, in the rubbing operation, an orientation function can be imparted without causing breakage, and ultrasonic cleaning was performed in isopropyl alcohol to remove abrasion powder of the resin layer due to rubbing. No erosion was observed.

Example 2 An optical element was formed in the same manner as in Example 1 except that a heat-resistant polymer film of polyetherimide was used as a temporary support.

Example 3 An optical element was formed in the same manner as in Example 1 except that a polyarylate heat-resistant polymer film was used as the temporary support.

Example 4 An optical element was formed in the same manner as in Example 1 except that a heat-resistant polymer film of polyetheretherketone was used as a temporary support.

In each of Examples 2 to 4, the optical element of the present invention could be easily formed in the same manner as in Example 1.

[Comparative Example 1] A glass substrate having a thickness of 1.1 mm (manufactured by Corning (product number) # 7059) was used as a temporary support in place of the polyimide film.
An optical element was formed in the same manner as in Example 1. However, in this example, it was difficult to peel off the laminate from the glass substrate, and the laminate could not be transferred to the transparent substrate.

[0038]

As described above, according to the present invention, an optical element excellent in various properties required as an optical element, that is, excellent in mechanical strength, chemical resistance and the like, and a laminate suitably used for the production thereof. A body transfer sheet can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing one embodiment of an optical element of the present invention.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 Adhesive layer 3 Laminated body 4 Temporary carrier 31 Transparent conductive layer 32 Resin layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B32B 27/34 B32B 27/34 C09J 133/08 C09J 133/08 C23C 14/08 C23C 14/08 D G09F 9/35 303 G09F 9 / 35 303 // C09D 179/08 C09D 179/08 Z C09J 4/02 C09J 4/02

Claims (4)

[Claims] 1. A transparent substrate, a radiation-crosslinked adhesive layer formed by laminating on the transparent substrate, and a laminate formed by transferring from a temporary carrier onto the adhesive layer. An optical element comprising: a transparent conductive layer formed in close contact with the adhesive layer; and a resin layer formed by being laminated on the transparent conductive layer. An optical element comprising a polyimide-containing coating film that has been subjected to a baking treatment before the transfer from the temporary support of the laminate to the adhesive layer. 2. The optical element according to claim 1, wherein the adhesive contains, as an adhesive component, an acrylate compound containing a polyfunctional (meth) acrylate monomer. 3. A laminated body transfer sheet used for manufacturing an optical element, comprising: a temporary carrier; and a coating film containing a baked polyimide which is provided on the temporary carrier in a releasable manner. A resin layer, a transparent conductive layer formed by being laminated on the resin layer,
A radiation-crosslinkable adhesive layer formed by laminating on the transparent conductive layer, wherein the temporary carrier does not contain fluorine atoms and silicon atoms in the molecule, and the sintering temperature of the resin layer Having a polymer surface made of a heat-resistant polymer having a glass transition temperature (Tg) of more than 2,000, and a resin layer having a polyimide-containing coating applied to the polymer surface of the temporary support and then subjected to a baking treatment. A laminated body transfer sheet comprising: 4. The sintering temperature of the resin layer is 80 to 300.
The laminate transfer sheet according to claim 3, wherein the temperature is ℃.