JP2001279011A - Method for forming film on plastic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of warpage, crack, etc., caused by a film- forming stress in the forming of an inorganic film, etc., on a plastic substrate. SOLUTION: A film is applied to a plastic substrate having thermal expansion coefficient different from that of the film by bending the substrate to a curvature to give a coated substrate having flat surface at normal temperature and applying the film to the bent substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for forming a film on a plastic substrate useful in the field of electronic materials and the like.
More specifically, the present invention relates to a method for manufacturing a plastic substrate having an inorganic film.

[0002]

2. Description of the Related Art In recent years, in the field of electronic materials, particularly in the field of portable equipment, plasticization has been promoted for reasons such as lightness and cracking. Among them, substrates for liquid crystal displays
Generally, glass having excellent heat resistance, dimensional stability, gas barrier properties, and the like is used, but various attempts have been made to replace it with plastic. For example, JP
9-204545 Patent polymethylmethacrylate as publication, polycarbonate, polyethersulfone, or on general thermoplastic resins such as polyethylene terephthalate,, SiO _x undercoat film, ITO (Indi
An electrode substrate having an order of um tin oxide) has been proposed. As described above, an electrode film such as a tin oxide film or an ITO film is generally formed on a plastic substrate by vacuum evaporation, sputtering, ion plating, or the like. Requires film formation under heating, and there is a problem such as warpage caused by a difference in thermal expansion coefficient with the base material. Further, when an inorganic film such as SiO ₂ is provided on the substrate to provide gas barrier properties, cracks and the like may occur due to stress of the electrode film. To solve this problem, Japanese Unexamined Patent Publication No.
A method of thickening one of the coat layers of a substrate described in JP-A-66411 or a method of applying a transparent conductive film to both surfaces of a substrate and peeling it later described in JP-A-7-175055 are proposed. However, an increase in the number of steps is inevitable, which is not preferable in terms of productivity. Also, Japanese Patent Application Laid-Open
Japanese Patent Application Laid-Open No. 64067/1994 proposes a method of manufacturing a resin substrate by applying a curvature in advance. However, distortion is finally left on the substrate, which is not preferable in terms of productivity. .

Attempts have also been made to form an electrode film at a low temperature, but none of such electrode substrates can sufficiently satisfy the required characteristics such as low resistance, chemical resistance and adhesion. unknown.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to suppress the occurrence of warpage, cracks and the like caused by film forming stress when forming an inorganic film or the like on a plastic substrate.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have formed a film having a different thermal expansion coefficient from a plastic substrate on a plastic substrate. The inventors have found that by forming a film by bending the substrate to have a curvature such that the substrate becomes flat at room temperature, stress distortion and warpage after film formation can be suppressed, and the present invention has been completed.

That is, the present invention provides a method for forming a thin film having a different thermal expansion coefficient from a plastic substrate on a plastic substrate, wherein the film is formed by bending the substrate to have a curvature such that it becomes flat at room temperature after the formation. Characterized by
A method of forming a plastic substrate, wherein the thin film is a transparent conductive film made of a metal oxide film, wherein the plastic substrate has an inorganic gas barrier film formed on the substrate in advance. The method for forming a plastic substrate according to any one of claims 1 to 3, wherein the plastic substrate has a SiO ₂ film formed in advance by a liquid phase deposition method on the substrate. Features,
The method for forming a plastic substrate according to any one of the above, wherein the plastic substrate has the following general formula (1) in one molecule:
Resin (resin) obtained by polymerizing a monomer (A) having both a functional group represented by the following formula (2) and a functional group represented by the following general formula (2) or (3): -A),

[0007]

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(In the above formula, R ₁ represents a hydrogen atom or a methyl group, and X represents an oxygen atom or a sulfur atom.) Alternatively, the monomer (A) and the following formulas (4), (5) and (6) By copolymerizing a monomer (B) having m (m is an integer of 1 to 6) at least one kind of functional group selected from the functional group group represented by (Chem. 4) Resin (resin-b)
A method for forming a film on a plastic substrate according to any one of claims 1 to 4.

[0009]

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[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The method for forming a plastic substrate of the present invention eliminates the warpage of the formed substrate by forming a thin film in a state where the substrate has a predetermined curvature.

As the plastic substrate in the present invention, any resin can be used, and it is preferable that the plastic substrate is a transparent resin substrate. For example, acrylic resin, polycarbonate resin, polyester, polyether sulfone and the like can be mentioned. Among them, a three-dimensional cross-linkable resin, for example, a cross-linked acrylic resin is preferable from the viewpoint of heat resistance, retardation and the like.

The resin having a three-dimensional crosslinked structure used in the present invention is more preferably the above-mentioned (resin-a) or (resin-b). (Resin-a) is a monomer having both a functional group represented by the general formula (1) and a functional group represented by the general formula (2) or (3) in one molecule. A)
And a monomer having m (where m is an integer of 1 to 6) at least one functional group selected from the functional group group represented by the formulas (4), (5) and (6) And B). These (Resin-a) and (Resin-b) are disclosed in JP-A-2-84406, JP-A-3-3-1.
48042, JP-A-3-478172, JP-A-3-725132, JP-A-3-179015
And JP-A-4-266927.

The monomer (A) having both the functional group represented by the general formula (1) and the functional group represented by the general formula (2) or (3) in one molecule includes, for example, , Isopropenyl-α, α-dimethylbenzyl isocyanate and 1
It is obtained by reacting a compound (compound P) having at least either a hydroxyl group or a mercapto group in the molecule and a functional group represented by the general formula (2) or (3). Examples of the compound P include: 1. Compounds obtained by opening a ring of an epoxy group or a thiirane group with acrylic acid or methacrylic acid, for example, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, 1,4- Butylene glycol monoacrylate, 1,4-butylene glycol monomethacrylate, glycerol-1,2-diacrylate,
Glycerol-1,2-dimethacrylate, glycerol-1,3-diacrylate, glycerol-1,3-
Dimethacrylate, glycerol-1-acrylate-
3-methacrylate, 2. Ring-opening reaction product of acrylic acid or methacrylic acid of phenylglycidyl ethers, for example, 3-phenoxy-2
-Hydroxypropyl acrylate, 3-phenoxy-
2-hydroxypropyl methacrylate, 2,4-dibromophenoxy-2-hydroxypropyl acrylate, 2,4-dibromophenoxy-2-hydroxypropyl methacrylate, 3. Ring opening reaction of acrylic acid or methacrylic acid of bisphenol A-diglycidyl ether Pentaerythritol triacrylate, pentaerythritol trimethacrylate, 5. vinylbenzyl alcohol, vinylthiobenzyl alcohol, 6. bis (acryloyloxyethyl) isocyanurate, bis (methacryloyloxyethyl) isocyanurate, and the like.

That is, the monomer A is a carbamate or a thiocarbamate, for example, by reacting an isocyanate group of isopropenyl-α, α-dimethylbenzyl isocyanate with a hydroxyl group or a mercapto group of the compound P. can get. In this reaction, a tin compound such as dibutyltin dilaurate or dimethyltin dichloride, or an amine such as morpholine or dimethylaminobenzene may be added so that the synthesis reaction proceeds easily. Note that it is preferable to select a tin compound in order to prevent coloring due to a radical reaction at the time of subsequent polymerization. When a solvent is used during the reaction, the solvent is distilled off after the synthesis reaction, and the monomer (A) is obtained without purification or without purification.

As the monomer (A), specifically, N-
(3-isopropenyl-α, α-dimethylbenzyl)-
2-acryloyloxyethyl carbamate, N- (3
-Isopropenyl-α, α-dimethylbenzyl) -2-
Methacryloyloxyethyl carbamate, N- (4-
Isopropenyl-α, α-dimethylbenzyl) -2-acryloyloxyethyl carbamate, N- (4-isopropenyl-α, α-dimethylbenzyl) -2-methacryloyloxyethyl carbamate, N- (3-isopropenyl-α , Α-dimethylbenzyl) -1-acryloyloxypropan-2-ylcarbamate, N- (3
-Isopropenyl-α, α-dimethylbenzyl) -1-
Methacryloyloxypropan-2-ylcarbamate, N- (4-isopropenyl-α, α-dimethylbenzyl) -1-acryloyloxypropan-2-ylcarbamate, N- (3-isopropenyl-α, α-dimethylbenzyl) ) -1,3-Diacryloyloxypropan-2-ylcarbamate, N- (3-isopropenyl-α, α-dimethylbenzyl) -1,3-dimethacryloyloxypropan-2-ylcarbamate, N- (3
-Isopropenyl-α, α-dimethylbenzyl) -1-
Acryloyloxy-3-methacryloyloxypropan-2-ylcarbamate, N- (4-isopropenyl-α, α-dimethylbenzyl) -1,3-diacryloyloxypropan-2-ylcarbamate, N- (3-
Isopropenyl-α, α-dimethylbenzyl) -2,2
-Diacryloyloxymethyl-3-acryloyloxypropylcarbamate, N- (4-isopropenyl-
α, α-dimethylbenzyl) -2,2-dimethacryloyloxymethyl-3-methacryloyloxypropylcarbamate. In addition, as a compound obtained by a reaction between an isocyanate compound and a mercapto group, a compound in which the above carbamate is converted to a thiocarbamate is used.

The monomer (B) is represented by the above formula (4) or (5)
And m (where m represents an integer of 1 to 6) at least one kind of functional group selected from the functional group group represented by (6), and an ester of acrylic acid or methacrylic acid;
Alternatively, it is a derivative of styrene.

Examples of m = 1 include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, benzyl acrylate, benzyl methacrylate, methoxy Ethyl acrylate, methoxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 1,4-butylene glycol monoacrylate, 1,4-butylene glycol monomethacrylate, glycidyl Acrylate, glycidyl methacrylate DOO, styrene, methyl styrene, chlorostyrene, bromostyrene, chloromethylstyrene, methoxystyrene, and the like.

Examples of those having m ≧ 2 include ethylene glycol diacrylate, ethylene glycol methacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, propylene glycol diacrylate, propylene glycol dimethacrylate, dipropylene glycol diacrylate, and dipropylene glycol diacrylate. Methacrylate, 2,2-bis (4-acryloyloxyethoxyphenyl) propane, 2,2-bis (4-methacryloyloxyethoxyphenyl) propane, 2,2-bis (4-acryloyloxydiethoxyphenyl) propane, 2, 2-bis (4-methacryloyloxydiethoxyphenyl) propane, 2,2-bis (4-acryloyloxypropyroylphenyl) propane 2,2-bis (4-methacryloyloxy propylonitrile yl) propane, 1,3
-Butanediol diacrylate, 1,3-butanediol dimethacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate,
1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, hydroxypentivalate neopentyl glycol ester diacrylate, spiro glycol diacrylate, spiro glycol dimethacrylate , Epoxy acrylate, epoxy methacrylate, 2-propenoic acid [2- (1,1-dimethyl-2-[(1
-Oxo-2-propenyl) oxy) ethyl] -5-ethyl-1,3-dioxan-5-yl] methyl ester, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate Bis (acryloyloxyethyl) hydroxyethyl isocyanurate, bis (methacryloyloxyethyl) hydroxyethyl isocyanurate, tris (acryloyloxyethyl) hydroxyethyl isocyanurate, tris (methacryloyloxyethyl) hydroxyethyl isocyanurate, petaerythritol tetraacrylate, Pentaerythritol tetramethacrylate, dipentaerythritol hexaacrylate, dipentae Sri Tall hexa methacrylate, methyl tri (acryloyloxyethoxy) silane, glycerol diacrylate, glycerol dimethacrylate, dibromo neopentyl glycol diacrylate, divinylbenzene, urethane acrylates,
Urethane methacrylates, 1,1,3,3,5,5-
Hexa (acryloyloxy) cyclotriphosphazene, 1,1,3,3,5,5-hexa (methacryloyloxy) cyclotriphosphazene, 1,1,3,3
5,5-hexa (acryloylethylenedioxy) cyclotriphosphazene and the like.

The monomer (A) is a monomer that can be polymerized alone, and (Resin-a) can be obtained by homopolymerization. Further, (Resin-b) can be obtained by copolymerizing the monomer (A) and the monomer (B). The ratio of the monomers (A) and (B) in this copolymerization cannot be determined unconditionally depending on the type of the functional group of each monomer and the structure of the monomer. Is the monomer (A) based on 1 equivalent of the isopropenylphenyl group in the monomer (A).
A functional group represented by the formula (2) or (3), and
It is preferable that the total of the functional groups represented by the formula (4), (5) or (6) in the monomer (B) is in the range of 0.5 equivalent to 10 equivalent.

Next, a method for producing the three-dimensionally crosslinked resin substrate of the present invention will be described. Preferably, the three-dimensional crosslinked resin substrate of the present invention is obtained by injecting the monomer (A) or a mixture of the monomers (A) and (B) into a space of a casting polymerization mold.
It is a resin having a transparent three-dimensional crosslinked structure obtained by polymerization and curing. Polymerization of the resin used in the present invention is radical polymerization, not only thermal polymerization, but also polymerization using ultraviolet rays or γ-rays is possible, and polymerization can be performed by further combining them. Is particularly preferred.
The radical polymerization initiator when performing the thermal polymerization is not particularly limited, and known benzoyl peroxide, p-chlorobenzoyl peroxide, diisopropylperoxycarbonate, di-2-ethylhexylperoxycarbonate, t-butylperoxypivalate Peroxides, such as
An azo compound such as azobisisobutyronitrile can be used. The amount used is 0.01% by weight based on the total amount of the monomers.
~ 5% by weight. Heating temperature in thermal polymerization is 50 ° C
To 200 ° C., and the heating time is 1 hour to 8 hours.

The photosensitizer in the case of curing by ultraviolet rays is not particularly limited, and is a known benzoin compound, benzoin methyl ether, benzoin ethyl ether, 2-hydroxy-2-benzoin propane, azobisisobityronitrile, benzyldimethyl. Ketal, diphenyl disulfide and the like can be used, and the amount used is 0.01% by weight to 5% by weight based on the total amount of the monomers. When radiation such as γ-rays is used, generally, a polymerization initiator or the like is not necessarily required.

In order to prevent the transparent resin substrate of the present invention from being colored or degraded with time and to prevent electrification, an antioxidant or An antistatic agent or the like can be added. Further, if necessary, other reactive monomers may be appropriately added. The monomer liquid thus adjusted is subjected to a defoaming treatment, if necessary, to prepare for polymerization.

The casting polymerization mold used in the production of the transparent resin substrate of the present invention includes two plate members selected from glass, metal, FRP and the like, soft vinyl chloride, elastomer,
It comprises a sheet or tube-like gasket such as silicone rubber or Teflon (registered trademark) or the like, and a fixture for fixing them. In order to obtain a resin plate having excellent surface accuracy, a glass plate or an FRP plate preferably has a polished surface, and a metal plate has a plated surface. In the case of thermal polymerization, it should not be one that lacks heat-induced deterioration or dimensional stability.
The plate material is selected in consideration of this point. The fixing tool may be in any form, but a stationery binder clip or the like can be easily used.

In the production of the transparent resin substrate of the present invention,
It does not necessarily require a release agent. However, in the case of manufacturing a relatively thin and large transparent resin substrate, a release agent can be used in order to release the mold more smoothly and better. At this time, any of an external release agent and an internal release agent can be used as the release agent, but from the viewpoint of rationalization of the molding process, the internal release agent is preferable. The internal release agent can be selected from commonly used internal release agents such as a silicone type, a wax type, a fatty acid metal soap type, a fluorine type, and an acidic phosphate ester type. The amount used is not generally determined by the type of the release agent or the type of the monomer of the resin, but is usually 0.02% by weight to 0.3% by weight based on the total amount of the monomers. . 0.02
If the content is less than 0.3% by weight, the effect of the release agent cannot be expected, and if the content is more than 0.3% by weight, the releasability is not changed. Excessive use tends to cause a decrease in the pot life of the monomer, a change in the resin properties, and the like, and is not preferred. A more preferred internal release agent is an acidic phosphate ester system which has particularly good release performance and is inexpensive and easy to handle. When an internal release agent is used, it is added at the same time as the radical initiator and other additives are added.

The thickness of the plastic substrate used in the present invention is usually 0.1 to 2 mm, preferably 0.2 to 1.5 mm.
mm, and more preferably 0.3 to 1.1 mm. When the substrate is less than 0.1 mm, it is difficult to handle because of lack of rigidity. When the substrate is thicker than 2 mm, a considerable force is required to apply a curvature, and productivity is deteriorated. As a method of forming the thin film of the present invention, a known film forming method, for example, a known method such as a spray method, a coating method, and a vacuum processing method can be used. Here, the vacuum processing method is a method of forming a thin film of a metal or the like generally under a vacuum, such as a vacuum evaporation method, a sputtering method, an ion plating method, a plasma CVD method, an ion cluster beam method, and an ion deposition thin film formation method. Can be used. Of these, a sputtering method and an ion plating method are preferably used. The film forming method of the present invention is characterized in that, when film formation is performed by these methods, the substrate is bent to have a curvature such that the substrate becomes flat after the film formation. FIG. 1 shows an example of forming a film on a substrate with a curvature. The transparent resin substrate 1 in FIG. 1 may be provided with various films such as an inorganic gas barrier film 2 on both sides or one side. This substrate is bent to a desired curvature by a substrate holding jig (holder) 3, and a thin film having a different thermal expansion coefficient from that of the substrate is formed from the upper part of the figure. Is obtained. The curvature in this case is determined by the temperature at which the thin film is formed, the coefficient of thermal expansion between the substrate and the thin film, and is not particularly limited. The material of the thin film having a different coefficient of thermal expansion from the substrate provided on the plastic substrate of the present invention is not particularly limited. The method of the present invention is effectively used when a material for a conventional transparent conductive layer, for example, a metal oxide is used.
Specifically, SnO ₂ , CdO, ZnO, CTO-based (C
dSnO ₃ , Cd ₂ SnO ₄ , CdSnO ₄ ), In ₂
O ₃ and CdIn ₂ O ₄ are exemplified. Preferably, it is a composite (doped) phase in which one or more selected from Sn, Sb, F and Al are added to the above metal oxide. Among them, In ₂ O to which Sn is added is preferable.
₃ (ITO), a SnO ₂ or the like with the addition of _SnO 2, F added with Sb, are particularly ITO is preferable.
The amount of tin contained in the ITO is not particularly limited, but is 0 to 25 parts by weight, preferably 5 to 5 parts by weight, based on indium 100.
18 parts by weight is suitable. Note that these transparent metal oxides may contain a trace amount of impurities.

The thickness of these thin films can be arbitrarily set according to the purpose and material. In the case of the above-mentioned metal oxide, the thickness is 100 to 4000 °, preferably 200 to 300 °.
0 °, more preferably 300 to 2000 °. still,
When the thickness of the metal oxide film is 100 ° or less, sufficient conductivity cannot be obtained, and the scratch resistance as a transparent conductive film is not sufficient. On the other hand, a film thickness of 4000 ° or more not only eliminates the necessity, but also leads to an increase in manufacturing cost, and further causes undesired results such as a decrease in transparency and coloring due to light interference.

As long as the object of the present invention is not impaired, one or more layers may be provided on both sides or one side of the resin substrate in advance. For example, for the purpose of improving the adhesion between the substrate and the transparent electrode layer, and preventing cracks caused by the difference in the coefficient of thermal expansion between the substrate and the transparent metal oxide film,
In some cases, a primer layer is used. Examples of such a resin include an acrylic resin, an epoxy resin, a polyester resin, a polyamide resin, a urethane resin, a phenol resin, a fluorine resin, a silicone resin, and an ethylene resin.
Vinyl alcohol-based polymer, acrylonitrile-butadiene-based resin (for example, ABS-based resin) and vinyl chloride-
At least one selected from vinyl acetate resin-based polymers
Types of resins, among which silicone resins are preferred, and silicone-based hard coat materials having an intermediate coefficient of thermal expansion between the resin and the metal oxide film are particularly preferred. The silicone-based hard coat material is generally used for the purpose of imparting abrasion resistance to plastic, and is generally an organosilicon compound represented by the following general formula (7), and a hydrolyzate thereof, R _n Si ( OR ′) _4-n (7) Metal oxide fine particles containing (R, R ′ being an organic group having 1 to 10 carbon atoms, n being an integer of 1 to 4) as a main component and being dispersed in a colloidal form as required. , A curing catalyst, an organic solvent and the like are mixed, prepared, applied, and cured. In addition, these film-forming components containing a silicone-based resin as a main component include acrylic resins, polyurethane-based resins, epoxy-based resins, melamine-based resins, polyolefin-based resins, and polyvinyl alcohol as long as their properties are not impaired. It is also possible to add a base resin, a urea resin, a polycarbonate base resin or the like.

The silicone hard coat is applied by a usual coating method, that is, dip coating, spin coating, spray coating, roll coating, bar coating, flow coating, brush coating, or the like. After coating by such a method, it is fired usually in the range of 50C to 250C, preferably 100C to 200C. If the substrate is subjected to a surface treatment such as an alkali treatment, a plasma treatment, and a sanding process before the application, the adhesion to the substrate is further improved.

Further, for the purpose of imparting gas barrier properties,
In some cases, a gas barrier layer is provided. With gas barrier layer
Although not particularly limited, SiO 2_xAnd S
iN _xInorganic gas barrier film such as a film has gas barrier properties
Is preferred. PVD (sputtering method)
Etc.), CVD, sol-gel method, coating of polysilazane paint
Ceramics-based coatings formed by cloth-firing etc.
Are known, such as a liquid deposition method and a liquid phase deposition method.
Is possible, but better barrier properties can be obtained.
It is preferable to provide it on both sides to reduce the number of processes.
Rugel method, ceramic coating method, liquid phase deposition
It is preferable to provide them in advance without distortion by a method or the like.
Good. In the liquid phase deposition method, the substrate is placed in an aqueous solution of saturated hydrofluoric acid.
Is immersed in the SiO.sub.2 on the substrate.₂Is deposited
Is useful as a gas barrier membrane,
It is also used as an antireflection film and an insulating film. This method
Room-temperature film formation is possible, so there is almost no distortion, and both sides are simultaneously
Productivity is good because a film can be formed. But
However, since a dense film is formed, metal oxide is added from above.
Are cracks particularly likely to occur when film is formed under heat?
Therefore, it is effective to use the film forming method of the present invention.

These layers can be used in combination as needed, or can be combined differently depending on the surface.

[0031]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not particularly limited thereto. In addition, the measured value in an Example is based on the following method. Electric resistivity: Measured by a four-probe method and converted to obtain sheet resistivity. Visible light transmittance: measured according to JIS-R-3106 method. A) Appearance: When observed with the naked eye, those having no cracks, rough surfaces or other defects in the coating film were evaluated as (（), and the others were evaluated as (x). B) Warpage of the substrate) A substrate of 10 cm square was placed on a flat table, and a substrate with no clearance of 1 mm or more was marked with (○), and the others were marked with (x). C) Adhesion: A cross-cut peeling test was performed, and the number of cross-cuts of the thin film remaining without peeling was counted, and those that did not peel off were counted (100/100), and those that were completely peeled off were evaluated as (0/100).
/ 100), and those with partial peeling were observed (n / 10
0).

[Plastic substrate (three-dimensional crosslinked resin plate)
Production of Resin] 1: Resin plate 1: After mixing 30.2 parts by weight of 3-isopropenyl-α, α-dimethylbenzyl isocyanate and 43.2 parts by weight of tris (acryloyloxyethyl) isocyanurate, dibutyltin dilaurate 0.02 was mixed.
After adding 19.5 parts by weight of 2-hydroxyethyl acrylate, the mixture was reacted at the same temperature for 2 hours, and then triethylene glycol diacrylate was added. Mix 12.5 parts by weight
did. T-butyl peroxy-2 was added to the obtained monomer.
-Ethyl hexanoate (1.16 parts by weight) was added, and the mixture was defoamed while mixing. Next, the de-processed monomer liquid is poured into a space of a mold prepared by using a silicon rubber sheet gasket so that two glass plates having a size of 200 mm × 300 mm have a space distance of 0.4 mm.
After placing in a hot air oven, polymerization was performed for 3 hours by heating at a temperature of 60 ° C. to 180 ° C., and a transparent resin plate 1 having a thickness of 0.4 mm was obtained.
I got The glass transition temperature of the obtained resin was 300 ° C., the flexural modulus was 440 kgf / mm ² , and the visible light transmittance was 90.2%.

Resin plate 2: 3-isopropenyl-α, α
To 45.6 parts by weight of dimethylbenzyl isocyanate and 4.7 parts by weight of ethylene glycol, 0.02 parts by weight of dibutyltin dilaurate was added as a reaction catalyst, and the reaction was carried out for 1 hour while maintaining the internal temperature at 40 ° C. To this reaction solution was added 9.8 of 2-hydroxyethyl methacrylate.
The reaction was carried out for 2 hours while maintaining the internal temperature at 50 ° C. Thereafter, 39.9 parts by weight of pentaerythritol tetraacrylate was added to the reaction solution, and the mixture was stirred well. Further, 0.100 part by weight of t-butylperoxy-2-ethylhexanoate was added, and the mixture was stirred well. Foam went. The obtained monomer liquid was polymerized in the same manner as in the case of the resin plate 1 to obtain a transparent resin plate 2 having a thickness of 0.4 mm. The glass transition temperature of the obtained resin was 210 ° C., the flexural modulus was 463 kgf / mm ² , and the visible light transmittance was 90.1%.

Resin plate 3: 3-isopropenyl-α, α
-30.2 parts by weight of dimethylbenzyl isocyanate,
Mix 42.3 parts by weight of tris (acryloyloxyethyl) isocyanurate, and maintain the internal temperature at 50 ° C.
Stir for 0 minutes. Next, dibutyltin dilaurate 0.0
2 parts by weight and 2-hydroxyethyl methacrylate
5 parts by weight were added, and the reaction was carried out for 5 hours while maintaining the internal temperature at 50 ° C. Then, t-butyl peroxy-
0.100 parts by weight of 2-ethylhexanoate, 0.2 parts by weight of Irgacure 651 (manufactured by Ciba Geigy), internal release agent of acidic phosphate ester type (trade name: Zelec U)
N, manufactured by Du Pont) and then defoamed. This monomer was poured into the same mold as in Example 1,
A metal halide lamp of 80 W / cm is irradiated for 240 seconds from a distance of 30 cm from above and below the mold to a thickness of 0.4 mm.
Was obtained. The glass transition temperature of the obtained resin is 280 ° C., and the flexural modulus is 444 kgf / m.
m ² , and the visible light transmittance was 91.0%.

[Preparation of Silicone Hard Coat Solution (Primer Layer)] γ-glycidoxypropyltrimethoxysilane 10
6.2 parts by weight kept at 10 ° C.
24.3 parts by weight of a 2% aqueous hydrochloric acid solution were gradually added dropwise. After the completion of the dropwise addition, the cooling was stopped to obtain a silane hydrolyzate. To this solution, 125.4 parts by weight of methanol-dispersed colloidal silica (“Methanol Silica Sol” manufactured by Nissan Chemical Co., Ltd., solid content: 30%, average particle diameter: 13 ± 1 μm) was added with stirring, and then 43.5 parts by weight of methanol Parts, 12.5 parts by weight of diethylene glycol dimethyl ether and 0.4 parts by weight of a silicone surfactant, 3.8 parts by weight of aluminum acetylacetonate were further added, and the mixture was sufficiently stirred to prepare a composition 1 for a primer. 178. Isopropyl alcohol in 18 parts by weight of vinyltriethoxysilane.
2 parts by weight were added, and while stirring, 1.28 parts by weight of a 0.01% aqueous hydrochloric acid solution was gradually added dropwise. After completion of the dropwise addition, the mixture was stirred at room temperature for 1 hour to prepare a composition 2 for a primer.

(Example 1) On one side of the resin plate 1 having a thickness of 0.4 mm, ITO (thin content: 5%) having a thickness of 700 ° was provided.
The film was fixed by making the ITO side concave so that the substrate became flat after the film formation, and was formed at 100 ° C. by a sputtering method. The visible light transmittance of the obtained transparent electrode substrate was 89.
5%, and the electric resistance was about 100Ω / □. The appearance of the coating film, the warpage of the substrate, and the adhesion were measured according to the above-mentioned inspection methods, and the results are shown in Table 1.

Example 2 An epoxy overcoating agent (AC510) was applied to one side of the resin plate 1 having a thickness of 0.4 mm.
0, manufactured by Nissan Chemical Industry Co., Ltd.) using a spin coater (1000 rpm, 20 seconds) and heat treatment at 150 ° C. for 30 minutes to obtain a 2 μm thick primer layer. On top of this coat, a 1300 mm thick ITO (tin content: 5
%) After forming the film, the ITO side was concaved and fixed so that the substrate became flat, and formed at 120 ° C. by a sputtering method. The visible light transmittance of the obtained transparent electrode substrate is 8
7.5%, and the electric resistance was about 30Ω / □.
Table 1 shows the results of the same inspection as in Example 1 performed on this substrate.

(Example 3) The primer composition 1 was applied to both surfaces of the resin plate 2 having a thickness of 0.4 mm using a spin coater (700 rpm, 15 seconds) and air-dried at room temperature for 30 minutes. After that, heat treatment was performed at 120 ° C. for 60 minutes to obtain a primer layer having a thickness of 3 μm. On both surfaces of the obtained substrate, perhydropolysilazane (20% xylene solution: manufactured by Tonen Co.) was applied using a spin coater (20).
00 rpm, 20 seconds), heated at 180 ° C. for 1 hour in the air atmosphere, immersed in 1% HCl aqueous solution, and
A 0 ° SiO ₂ coating was obtained. One side of this substrate has a thickness of 1
An ITO film of 300 ° was fixed by making the ITO side concave so that the substrate became flat after the film formation, and was formed by a high-frequency ion plating method. The visible light transmittance of the obtained substrate was 89%, and the electric resistance was 30 Ω / □. Table 1 shows the results of the same inspection as in Example 1 performed on this substrate.

(Example 4) An SiO ₂ film having a thickness of 500 ° was formed on both surfaces of the resin plate 3 having a thickness of 0.4 mm by sputtering, and then a film having a thickness of ₂ mm was formed on one surface of the substrate.
An ITO film of 600 ° was fixed by making the ITO side concave so that the substrate became flat after the film formation, and was formed at 200 ° C. by a sputtering method. The visible light transmittance of the obtained substrate was 88%, and the electric resistance was 10 Ω / □.
Table 1 shows the results of the same inspection as in Example 1 performed on this substrate.

Example 5 A SiO ₂ film having a thickness of 500 ° was formed on both sides of a polycarbonate film having a thickness of 50 μm by a sputtering method. Subsequently, ITO (thin content: 700) having a thickness of 700 ° was formed on one surface of the substrate. %) A film was fixed by making the ITO side concave so that the substrate became flat after the film formation, and formed by a sputtering method. The visible light transmittance of the obtained transparent conductive film was 82%, and the electric resistance was about 200 Ω / □. Table 1 shows the results of the same inspection as in Example 1 performed on this substrate.

Example 6 The resin plate having a thickness of 0.4 mm
The primer composition 2 was coated on both sides of
(2000 rpm, 15 seconds)
After air drying for 5 minutes, heat treatment at 200 ° C for 5 minutes,
A 10 nm-thick primer layer was obtained. The obtained substrate is
Immersed in saturated aqueous solution of silicon fluoride for 40 minutes,
ＳｉＯ SiO ₂A coating was obtained. One side of this substrate has a thickness of 13
The ITO film of 00Å is formed so that the substrate becomes flat after the formation.
Make the ITO side concave and fix it.
It was formed by a rubbing method. The visible light transmittance of the obtained substrate is
89%, and the electrical resistance was 30Ω / □. This group
The results of the same inspection as in Example 1 were performed on the plate (Table 1).
Shown in 1).

Comparative Example 1 A substrate was formed in the same manner as in Example 4 except that the ITO film was formed while keeping the substrate straight. The visible light transmittance of the obtained substrate was 88%, and the electric resistance was 10Ω. Table 1 shows the results of the same inspection as in Example 1 performed on this substrate.

Comparative Example 2 A 0.2 mm thick PET film was coated with an epoxy overcoating agent (AC5100,
Nissan Chemical Industry Co., Ltd.) (1000 rpm, 20 seconds)
Then, a heat treatment was performed at 110 ° C. for 30 minutes to obtain a primer layer having a thickness of 4 μm. On one surface of the obtained substrate, an SiO ₂ film having a thickness of 500 ° was formed by a sputtering method,
Furthermore, an ITO (tin content: 5%) film having a thickness of 600
The substrate was formed while being fixed straight. The visible light transmittance of the obtained transparent conductive film was 82%, and the electric resistance was about 200 Ω / □. The same inspection as in Example 1 was performed on this substrate. The results are shown in (Table 1).

(Comparative Example 3) The same monomer as that for the resin plate 2 was produced with a curvature so that the substrate became flat after the ITO film formation, and a transparent resin substrate having a thickness of 0.4 mm was obtained. The primer composition 2 was applied to both surfaces of the substrate using a dip coater, and air-dried at room temperature for 5 minutes.
Heat treatment was performed at 0 ° C. for 5 minutes to obtain a primer layer having a thickness of 10 nm. The obtained substrate was immersed in a saturated silicon fluoride aqueous solution for 40 minutes to obtain a 400 ° thick SiO ₂ coating film.
An ITO film having a thickness of 1300 ° was formed on the concave surface of the substrate by a high-frequency ion plating method while holding the substrate without applying a force. The visible light transmittance of the obtained substrate was 89%, and the electric resistance was 30 Ω / □. Table 1 shows the results of the same inspection as in Example 1 performed on this substrate.

[0045]

[Table 1]

Examples 1 to 6 produced as described above,
From the test results (Table 1) of the plastic substrates of Comparative Examples 1 to 3, it can be seen that Examples have less warpage and better adhesion than Comparative Examples.

[0047]

The substrate formed by the method for forming a plastic substrate of the present invention has no warpage, so that the post-process is easy, and a substrate with a transparent electrode with little residual distortion can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 transparent resin substrate 2 inorganic gas barrier film 3 substrate holding jig

Continued on the front page F-term (reference) 2H090 JB03 JC07 LA01 4F006 AA22 AA35 AA36 AB74 BA07 CA08 DA01 EA01 4F100 AA00C AA17B AA20B AA33 AK01A AK12A AK25A AK51 AL01A AL06 AT00A BA03 BA07 J11B01 J01B01 J02B10 BA48 BC09 CA03 CA05 FA07 JA01

Claims (5)

[Claims] 1. A method for forming a thin film having a different coefficient of thermal expansion from a plastic substrate on a plastic substrate, wherein the film is formed by bending the substrate to have a curvature such that it becomes flat at room temperature after the film is formed. , Plastic substrate film formation method. 2. The method according to claim 1, wherein the thin film is a transparent conductive film made of a metal oxide film. 3. The method for forming a plastic substrate according to claim 1, wherein the plastic substrate has an inorganic gas barrier film on the substrate in advance. 4. The plastic according to claim 1, wherein the plastic substrate has an SiO ₂ film formed on the substrate in advance by a liquid phase deposition method. Substrate deposition method. 5. A plastic substrate comprising, in one molecule, a functional group represented by the following general formula (1) and a general formula (2) or (3): A resin (resin-a) obtained by polymerizing a monomer (A) having a functional group; (In the above formula, R ₁ represents a hydrogen atom or a methyl group, and X represents an oxygen atom or a sulfur atom.) Alternatively, the monomer (A) and the following formulas (4), (5) and (6) A resin obtained by copolymerizing a monomer (B) having m (m is an integer of 1 to 6) at least one kind of functional group selected from the group of functional groups represented by (Formula 2) Resin-b)
The method for forming a plastic substrate according to claim 1, wherein: Embedded image