JP2002082223A - Protective film or polarizing plate, optical film and picture display material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical film such as a protective film for a polarizing plate, an antistatic film which are excellent in adhesion to a polyvinyl alcohol sheet and are manufactured with safety in operation and by processing without any adverse effect on environment, a polarizing plate, a liquid crystal display and further a picture display material using the films. SOLUTION: The protective film for the polarizing plate is characterized by having a layer with >=10.0 mN/m polar term component of surface energy, <=0.1 μm film thickness and >=90% transmittance on one surface of a transparent substrate film, to which a polarizer is adhered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an optical film,
In particular, the present invention relates to a protective film for a polarizing plate used for a liquid crystal display, a polarizing plate, and an image display material using the optical film for improving storage stability of an image.

[0002]

2. Description of the Related Art Various optical films are used in liquid crystal displays and plasma displays. Functional films such as a polarizing plate (film), a retardation film, and a viewing angle widening film are used for a liquid crystal display, and these films are mainly produced by coating or laminating. Above all, the polarizing plate has a structure in which a protective film for a polarizing plate made of cellulose ester is laminated on both sides of a polarizer made of a polyvinyl alcohol film or the like in which iodine or a dye is adsorbed and oriented. However, in the process of manufacturing a polarizing plate, a process of saponifying a cellulose acetate film with a strong alkali is performed, and has problems such as maintenance, safety, and environment related to waste liquid. JP-A-6-94915 and JP-A-6-118252
Nos. 7-333436 and 8-96801 propose a method of solving the above problem by applying an easy-adhesion layer to a base film. However, the method of forming an easily-adhesive layer by coating has a problem of a yield problem due to a coating defect due to dust, foreign matter, and the like, and has a problem that equipment such as a coating line and a drying line is required and costs are increased. .

As another optical film, there is, for example, a triacetyl cellulose film having an antistatic property. As described in JP-A-6-123806, an antistatic layer containing a metal oxide or an ionic polymer is used. Is known. However, when a resin film on which an antistatic layer is formed by a coating method is used as a protective film for a polarizing plate, there is a problem in that the curl becomes large due to the influence of a coating solvent on a substrate, or the antistatic layer is not used. There was a drawback that blocking occurred on the back surface and reduced productivity. Further, when forming an antistatic layer by coating, there is a problem that coating failure occurs due to mixing of dust and foreign matter, and the yield is reduced.

[0004] On the other hand, a technique for modifying the surface of a film or forming a thin film by plasma processing is a technique that has been attracting attention in recent years because continuous processing is possible and processing is simple. As a result of various studies, the inventors of the present invention have found that the technology of surface modification and thin film formation by performing plasma discharge treatment in the presence of a reactive gas has been developed for protective films for polarizing plates and polarizing plates (films). It was found to be particularly effective in optical films.

Further, as another application of the optical film, there is a use as an image display film used for laminating an image. For example, an image outputted by an ink jet has a drawback that image storability is poor and fading easily occurs. Improvements are desired, and post-treatments such as lamination with a polyester film and an adhesive have been performed.However, in the conventional lamination method using a film and an adhesive, the laminating operation is complicated or bubbles are generated. There were problems such as mixing. Many ink receiving layers of ink jet recording paper are mainly composed of polyvinyl alcohol, and a laminate film having better adhesion to these ink receiving layers has been desired.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a process which is excellent in adhesion to a polyvinyl alcohol film or a sheet having a polyvinyl alcohol-containing layer used in a polarizer or an ink-jet image-receiving sheet and which is safe and environmentally friendly to work. To provide an optical film such as a protective film or an antistatic film for a polarizing plate and a polarizing plate using the same, which can be produced by processing that has no adverse effect, and to provide a liquid crystal display. It is an object of the present invention to provide an image display material that can be used together with an ink jet recording paper and can integrally improve the storability of an image.

[0007]

The above object of the present invention is achieved by the following means.

[0008] 1. On the surface of the transparent substrate film to which the polarizer is bonded, the polarity term component of the surface energy is 10.0 mN /
A protective film for a polarizing plate, comprising a layer having a thickness of 0.1 μm or less that is not less than m and having a transmittance of 90% or more.

[0009] 2. In a protective film for a polarizing plate having a layer having a thickness of 0.1 μm or less on a surface of a transparent substrate film to which a polarizer is adhered and having a transmittance of 90% or more, the protective film for a polarizing plate having a thickness of 0.
Elemental ratios of oxygen, nitrogen, and phosphorus to carbon on the surface of the layer of 1 μm or less are Ocl, Ncl, Pcl, and oxygen, nitrogen, and phosphorus for carbon on the surface of the base film excluding the layer having a thickness of 0.1 μm from the surface. Element ratio is O
When expressed as cs, Ncs, Pcs, Ocl / Ocs,
A protective film for a polarizing plate, wherein one of the values of Ncl / Ncs and Pcl / Pcs is 1.1 or more.

[0010] 3. In a protective film for a polarizing plate having a layer having a thickness of 0.1 μm or less on a surface of a transparent substrate film to which a polarizer is adhered and having a transmittance of 90% or more, the protective film for a polarizing plate having a thickness of 0.
When polyvinyl alcohol (polymerization degree: 1500 or more, saponification degree: 98 to 99 mol%) is further applied on a layer having a thickness of 1 μm or less, the polyvinyl alcohol layer has a thickness of 0.1 μm.
When the cross-cut tape method conforming to JIS K-5400 is used for the adhesion to a layer having a thickness of not more than m, the number of cross-cuts remaining without peeling is 90 or more, and the polarizing plate is protected. the film.

4. The layer according to any one of the above items 1 to 3, wherein the layer having a thickness of 0.1 μm or less is formed by subjecting the transparent substrate film to plasma discharge treatment under a reactive gas atmosphere containing an organic compound. Item 2. The protective film for a polarizing plate according to item 1.

5. 5. The protective film for a polarizing plate as described in 4 above, wherein the organic compound is a compound having an unsaturated bond.

6. 6. The protective film for a polarizing plate as described in 5 above, wherein the compound having an unsaturated bond is a compound having at least a substituent selected from a hydroxyl group, a carbonyl group, a carboxyl group, and an epoxy group.

7. 6. The protective film for a polarizing plate according to the item 5, wherein the compound having an unsaturated bond is at least a compound selected from the general formulas I to IV.

[8] 5. The protective film for a polarizing plate as described in 4 above, wherein the organic compound is a compound having a nitrogen atom.

9. 9. The protective film for a polarizing plate as described in 8 above, wherein the compound having a nitrogen atom is at least a compound selected from the general formula V.

10. The protective film for a polarizing plate according to any one of the above items 4 to 9, wherein the reactive gas used for the plasma discharge treatment further contains a gas containing an oxygen atom.

11. The protective film for a polarizing plate according to any one of the above items 1 to 10, wherein a cellulose ester film, a polycarbonate film, a polyester film, a polylactic acid or a polyacryl film is used as the transparent substrate film.

[12] 12. The protective film for a polarizing plate according to any one of the items 4 to 11, wherein the pressure in the plasma discharge treatment is set to 0.007 to 27 hPa or less.

13. Wherein the plasma discharge treatment is performed at or near atmospheric pressure.
2. The protective film for a polarizing plate according to claim 1.

14. 14. The protective film for a polarizing plate as described in 13 above, wherein at least one of the electrodes used for the plasma discharge treatment has a solid dielectric.

15. 15. The protective film for a polarizing plate as described in 13 or 14, wherein the reactive gas used for the plasma discharge treatment further contains an inert gas.

16. 16. The protective film for a polarizing plate as described in 15 above, wherein the inert gas is an argon gas or a helium gas.

17. 15. The protective film for a polarizing plate as described in 13 or 14, wherein a pulse-like voltage is applied between the plasma discharge electrodes.

18. The rising or falling time of the pulse electric field created between the electrodes by application of the pulsed voltage is both in the range of 40 ns to 100 μs, and the intensity of the pulse electric field is in the range of 1 to 100 kV / cm. 18. The protective film for a polarizing plate as described in 17 above, which is characterized by:

19. The frequency of the pulse electric field is 1 kHz to 1
20. The protective film for a polarizing plate as described in 18 above, wherein the frequency is 00 kHz, and the formation time of one pulse electric field is 1 μs to 1000 μs.

20. 20. The protective film for a polarizing plate as described in 18 or 19 above, wherein a pulse electric field is generated by simultaneously applying different polar voltages to at least two opposing electrodes.

21. An inert gas or a mixed gas of an inert gas and a reaction gas is introduced into a slit-shaped reaction tube provided with an outer electrode and a reaction tube of a plasma processing apparatus provided with an inner electrode inside the reaction tube. An optical film characterized in that a surface treatment is performed by applying an AC electric field during the process to generate excited active species including plasma and spraying the excited active species onto a transparent substrate film.

22. An inert gas or a reaction gas containing an inert gas and a metal element-containing compound is introduced into a slit-shaped reaction tube having an outer electrode and a reaction tube of a plasma processing apparatus having an inner electrode inside the reaction tube. An optical field characterized by applying an alternating electric field between the electrode and the inner electrode to generate excited active species including plasma and performing a surface treatment by spraying the excited active species onto a transparent substrate film. the film.

23. 23. The optical film as described in 22 above, wherein the absolute value of the impedance at a frequency of 20 Hz is 4 × 10 ⁵ Ω or more.

24. 24. The optical film as described in any one of 21 to 23 above, wherein the transparent substrate film is cellulose acetate.

25. 24. The optical film as described in any one of 21 to 23 above, which is used as a protective film for a polarizing plate, a retardation film, or a brightness enhancement film.

26. 25. A polarizing plate using the optical film according to any one of 21 to 24.

27. A liquid crystal display using the optical film described in 25 above.

28. 27. A liquid crystal display using the polarizing plate described in 26 above. 29. A polarizing plate, wherein the protective film for a polarizing plate according to any one of 1 to 11 and a polarizer made of polyvinyl alcohol are bonded to each other.

30. 12. A method for producing a polarizing plate, comprising: washing the polarizing plate protective film with water before laminating the polarizer protective film described in any one of 1 to 11 and a polarizer made of polyvinyl alcohol.

31. A transparent substrate film having a layer formed by spraying excited active species including plasma discharge treatment or plasma under a reactive gas atmosphere,
A method for improving the storability of an image, comprising laminating an image display material having at least a layer containing polyvinyl alcohol, on which an image is formed, on a support.

32. A transparent substrate film having a layer formed by spraying excited active species including plasma discharge treatment or plasma under a reactive gas atmosphere,
An image display material having improved image storability characterized by laminating an image display material having at least a layer containing polyvinyl alcohol on a support on which an image is formed.

33. 32. The method for improving image storability according to the item 31, wherein the transparent substrate film is a cellulose ester film, a polycarbonate film, or a polyester film.

34. 33. The image display material as described in 32 above, wherein the transparent substrate film is a cellulose ester film, a polycarbonate film, or a polyester film.

35. The image display material having at least a layer containing polyvinyl alcohol on a support is an ink jet recording paper;
3. The method for improving image storability according to item 3.

36. 32 or 34, wherein the image display material having at least a layer containing polyvinyl alcohol on a support is an ink jet recording paper.
The image display material described in 1.

Hereinafter, the present invention will be described in detail. The transparent substrate film used in the present invention is not particularly limited, for example, polyethylene terephthalate, polyester film such as polyethylene naphthalate, polyethylene film, polypropylene film, cellophane, cellulose acetate film, cellulose acetate butyrate film, cellulose acetate phthalate film,
Cellulose acetate propionate film, cellulose triacetate, a film composed of cellulose esters such as cellulose nitrate or a derivative thereof, a polyvinylidene chloride film, a polyvinyl alcohol film, an ethylene vinyl alcohol film, a syndiotactic polystyrene film, a polycarbonate film, Norbornene resin film, polymethylpentene film, polyetherketone film,
Examples thereof include a polyether sulfone film, a polysulfone film, a polyether ketone imide film, a polyamide film, an acrylic film, and a polyacrylate film. In the present invention, a cellulose ester film such as a cellulose triacetate film (TAC film), a polycarbonate film, a polyester film, a polylactic acid, or a polyacryl film is particularly preferable in terms of transparency, mechanical properties, and absence of optical anisotropy. Further, a film in which these resins are laminated or a film in which these resins are mixed may be used, and a resin layer or an inorganic layer may be applied to these base materials according to the application. Among the films described above, the lower fatty acid ester of cellulose that is particularly preferably used is cellulose triacetate. Furthermore, from the viewpoint of base strength,
Particularly, the polymerization degree is 250 to 400, and the amount of bound acetic acid is 54.0 to 6
2.5% cellulose triacetate is preferably used, and the weight average molecular weight is 70,000 to 120,000.
0 is preferable, and 80,000 to 100,000 is more preferable. More preferably, the amount of bound acetic acid is 58-62.
5% cellulose triacetate. A film in which cellulose acetate propionate or cellulose diacetate is mixed with the cellulose triacetate at a ratio of 1: 9 to 9: 1 is also preferably used.

As the cellulose triacetate according to the present invention, either cellulose triacetate synthesized from cotton linter or cellulose triacetate synthesized from wood pulp can be used alone or in combination. During film formation by casting, if the releasability from the belt or drum becomes a problem, it is preferable to use a large amount of cellulose triacetate synthesized from cotton linter, which has good releasability from the belt or drum. . When cellulose triacetate synthesized from wood pulp is used by mixing, the ratio of cellulose triacetate synthesized from cotton linter is preferably 40% by mass or more, and the effect of releasability is remarkable, and more preferably 60% by mass or more. It is most preferred to use it alone.

Many of these cellulose esters are known as to a method for producing the cellulose ester by casting and additives of the cellulose ester.
Additives such as a matting agent, a plasticizer, and a UV absorber, and a method for producing a film by casting, for example, see JP-A-10-2371.
No. 86, Japanese Patent Application No. 11-238290, and No. 11-353
162, etc., and these techniques can be used.

The polarizer used in the present invention is a film in which iodine or a dichroic dye is adsorbed and oriented on a polyvinyl alcohol-based film, and the protective film for a polarizing plate is a film on which a polarizer is bonded, a polarizing plate. Refers to a film having a structure in which, for example, a triacetyl cellulose film is bonded to a polarizer as a protective film.

The protective film for a polarizing plate is preferably coated with a hard coat layer, an antiglare layer, an antireflection layer, a protective layer, an adhesive layer, an alignment film, and a liquid crystal layer. It is preferable to coat an antiglare layer, an antireflection layer, a protective layer, an adhesive layer, an alignment film, and a liquid crystal layer.

In the protective film for a polarizing plate of the present invention,
It was found that the surface energy of the surface layer was related to the adhesion to the polarizer. That is, in the present invention, the polarity term component of the surface energy of the layer surface composed of the polymer film of 0.1 μm or less formed on the surface of the base film by performing the plasma discharge treatment on the surface in the presence of the reactive gas is 10 mN. / M or more had good adhesion to the polarizer. Probably, the contribution of hydrogen bonding between the polar group on the surface or near the surface and the polyvinyl alcohol constituting the polarizer can be presumed to be large. The value of the polar component of the surface energy is 10 mN / m or more, preferably 15 mN / m or more, more preferably 20 mN / m or more. The upper limit of the value of the polar term component of the surface energy is about 40 mN / m. In general, the surface energy (surface tension) of the material forming the surface γ ^T
Is mainly the dispersion force component γ ^{d as} shown in the following equation (1).
And the polar term component γ ^p .

Γ ^T = γ ^d + γ ^p (1) Further, there is the following relational expression between the surface energy of the solid surface and the surface energy of the solvent: (1 + COS θ) γ _L ^T = 2 (γ _L ^d · γ _{^{S d) 1/2 +2 (γ L}} p + γ S p) 1/2 (2) θ is the contact angle (°), γ _L ^T, the surface energy of the solvent,
γ _L ^d is the dispersive force component of the surface energy of the solvent, γ _L ^p
A polar term component of the surface energy of the solvent, gamma _S ^d is the dispersion force component of the surface energy of the solid surface, gamma _S ^p represents the polar term component of the solid surface energy of the. The unit of energy is mN / m.

[0050] (2) from the equation, if the dispersion force component and a polar term component by measuring the contact angle using a known two solvents solving the simultaneous equations, gamma _S ^d and gamma _S ^p component of solid surface Desired. For example, the dispersing power component and the polar term component of water and methylene iodide used for obtaining the dispersing force component and the polar term component of the surface-modified film in Examples described later are shown below (JA).
dhsion, Vol. 2, p66 (1970)).

Solvent γ _L ^d γ _L ^p γ _L ^T Water 21.5 51.0 72.5 Methylene iodide 48.5 2.3 50.8 In the present invention, the measurement of the contact angle between water and methylene iodide Using a goniometer G1 manufactured by Elma Industry Co., Ltd., 5 μl is dropped on the surface of the base film, and the measurement is performed five times, and the average is used as the contact angle to calculate the surface energy.

In the present invention, it was also found that the element ratio on the film surface was related to the adhesiveness. That is, by analyzing the elements on the surface of the polymer film having a thickness of 0.1 μm or less formed by performing a plasma discharge treatment on the surface of the substrate film in the presence of a reactive gas, the proportion of oxygen, nitrogen, and phosphorus It was found that when the content was larger than that inside the substrate, the adhesion to the polarizer was good. It is presumed that in these polymerized films, the proportion of oxygen, nitrogen and phosphorus was increased as compared with the base film, so that the hydrogen bond with polyvinyl alcohol used for the polarizer was increased. In the present invention, the thickness of the polymer film formed on the surface of the base film by the plasma surface treatment varies depending on the conditions of the plasma treatment. .1 μm or less is preferred in terms of productivity. When the film thickness is large, the processing time is long, and the productivity is inferior. More preferably, it is 0.05 μm.

The substrate film may be any surface of the substrate film excluding the layer composed of the polymer film formed by the above-described plasma discharge treatment. In the present invention, the substrate film has a thickness of 0.1 μm from the surface. Oxygen, nitrogen and phosphorus atoms with respect to carbon atoms on the surface excluding the film layer are measured.

The element ratio on the surface of the polymer film formed by the plasma discharge treatment of the present invention and the oxygen relative to the carbon atoms on the surface of the substrate film, that is, excluding the layer comprising the polymer film having a thickness of 0.1 μm or less from the surface. , Nitrogen, and phosphorus atoms are in the following XPS (X-ray Pho)
(Spectroscopic Spectroscopy).

The element on the surface is XPS (X-ray Pho).
electron spectroscopy). When a solid sample surface is irradiated with X-rays, photoelectrons are emitted from atoms excited by the X-rays. If the kinetic energy of the photoelectrons is KE, the energy of the irradiated X-rays is hν, and the binding energy of the electrons is BE, the following equation is obtained. (3) is established.

KE = hν-BE (3) Since the electron binding energy has a value specific to each element, it is possible to identify the element by observing the photoelectron spectrum.

In the present invention, the layer having a thickness of 0.1 μm or less formed by the plasma discharge treatment is not limited as long as it has a polar component of surface energy of 10.0 mN / m or more. When the surface of the layer having a thickness of 0.1 μm or less is measured by the XPS, the ratio of each of oxygen, nitrogen, phosphorus, and atoms to carbon atoms on the surface is one of one of the above elements compared to the inside of the film substrate. The thickness is not limited, provided that it is at least 1 layer.
These layers can be manufactured by forming a polymer film on the transparent substrate film by plasma-treating the transparent substrate film in the presence of a reactive gas or spraying a reactive gas plasma, which will be described later. The film thickness can be adjusted by the conditions of these treatments.

The thickness of the polymer film formed in the present invention is preferably 0.1 μm or less from the viewpoint of productivity. When the film thickness is large, the plasma processing time required for the production is long, and the productivity is inferior. More preferably, it is 0.05 μm.

The element ratio of the surface measured by XPS is within a range of at most 10 nm from the surface. Therefore, the surface in the present invention is a composition ratio including a layer of at least 10 nm or less. It can be said that the surface is sufficiently thin and sufficient compared to a layer having a thickness of 0.1 μm or less.

In order to measure the ratio of the element ratio of oxygen, nitrogen and phosphorus to carbon on the surface of the layer of 0.1 μm or less to the inside of the substrate, the element ratio on the surface is measured, After removing the base film by a thickness of 0.1 μm (dissolving or mechanically) and exposing a new surface, the element ratios of oxygen, nitrogen and phosphorus to carbon are further measured by XPS. The element ratios of oxygen, nitrogen, and phosphorus to carbon on the surface measured in this manner are represented by Ocl, Ncl,
Ocl / Ocs, where Ocl, Ncs, and Pcs represent the elemental ratios of oxygen, nitrogen, and phosphorus to carbon on the surface of the substrate inside the Pcl, and further removing the thickness of 0.1 μm from the surface.
If any one of the values of s, Ncl / Ncs, and Pcl / Pcs is 1.1 or more, the adhesion to the polarizer becomes good. Preferably it is 1.2 or more, more preferably 1.5 or more. In order to increase the ratio of oxygen, nitrogen, and phosphorus on the surface of the film, it is preferable to perform plasma processing in the presence of a compound containing oxygen, nitrogen, and phosphorus in a reactive gas and a reactive gas containing oxygen in the plasma processing. .

The actual measurement of the element ratio of oxygen, nitrogen, and phosphorus to carbon on the measurement surface is performed by XPS measurement (ESCALAB).
-200R) using a Mg anode (600 W) and a silver plate having a clean energy resolution such that the half width of the Ag3d5 / 2 peak is 1.80 eV ± 0.2 when the peak is measured. Set. Each element is measured at an extraction angle of 90 degrees. In the present invention, the ratio of the area intensity of oxygen, nitrogen, and phosphorus atoms to the area intensity of the carbon peak is represented as the element ratio to carbon.

Polyvinyl alcohol for coating on a protective film for a polarizing plate having a thickness of 0.1 μm or less and having a transmittance of 90% or more in the present invention and having a film thickness of 0.1 μm or less in the present invention to check adhesion. Can be used as those generally available on the market. The polymerization degree is 1500 or more, and the saponification degree is 9
Use 8 to 99 mol%. After dissolving the polyvinyl alcohol in water or warm water, the polyvinyl alcohol layer is applied on the test surface of the protective film for a polarizing plate with a bar coater or the like, and dried at 80 ° C. for 30 minutes. The thickness of the formed polyvinyl alcohol layer is adjusted to 0.5 μm ± 10%. The evaluation of the adhesion of the polyvinyl alcohol layer is based on the grid tape method of JIS K-5400,
1mm using the specified cutter knife and cutter guide
One hundred squares are made at intervals, glued with a specified cellophane adhesive tape, and rubbed with an eraser to adhere to the coating.
Two minutes after application of the tape, it is momentarily peeled off in the direction perpendicular to the coated surface. If the number of remaining grids is 90 or more, it was found that the protective film for a polarizing plate had good adhesion to a polarizer and excellent durability.

The layer having a thickness of 0.1 μm or less according to the present invention can be produced by subjecting the transparent base film to a plasma discharge treatment under a reactive gas.

The plasma discharge treatment is to generate a plasma state by a discharge in a reactive gas and treat the surface of a film or the like with the plasma. These are disclosed in JP-A-06-123062 and JP-A-11-293011.
And a method described in JP-A-11-5857 can be used, and a plasma discharge treatment performed by applying a voltage to at least two opposing electrodes is preferable.

As the organic compound used as the reactive gas in the present invention, a compound which forms a polymer film on a substrate by plasma discharge treatment is used. As a compound that forms a polymerized film by plasma discharge treatment, any organic compound that can vaporize because it passes through a radical can be a polymerizable monomer.However, the degree of polymerization differs depending on the chemical structure and functional groups. Since there is a difference depending on the conditions, films having various characteristics can be produced. In the present invention, a compound having an unsaturated bond is preferably used because the formation rate of a polymer film is faster than that of a saturated compound and the film is strong (not easily damaged).

As the organic compound used as the reactive gas in the present invention, any compound having an unsaturated bond can be used by selecting the conditions of the plasma discharge treatment. Particularly, it is a compound having a substituent selected from a hydroxyl group, a carbonyl group, a carboxyl group, and an epoxy group.

The organic compound having an unsaturated bond, which is preferably used as a reactive gas in the present invention, is a compound represented by the above general formula. For the purpose of the present invention, among these, a hydroxyl group and a carbonyl group are particularly preferable. And a compound having a substituent selected from a carboxyl group and an epoxy group.

In the above general formula I, R ₁ and R ₂ represent hydrogen,
Represents an alkyl group which may have a substituent. Specific examples of the compound include compounds having an acetylene (ethynyl) group at the terminal, such as acetylene, propyne, and butyne-.
1, Hexin-1, octene-1, and compounds having an ethynylene group (—C≡C—) in the molecule include butyne-2, hexyne-2, hexyne-3, and octin-4. .

Examples of the compound having an aromatic group include phenylacetylene, 3-phenylpropyne and 4-phenylbutyne-1.

The compound represented by the general formula I is represented by O, N, F,
Field containing an atom selected from Cl, Br, Si, S
Examples of the case include an oxygen-containing acetylene compound such as 3
-Methyl-1-butyn-3-ol and 3-phenyl-
1-butyn-3-ol; silicon-containing acetylene-based compound
, For example, the 1-butyn-3-ol O-trimethyl
Lylated product (HC≡C-CH (CH_Three) -O-Si (C
H_Three)_Three) And 3-phenyl-1-propyn-3-ol
O-trimethylsilyl compound (HC≡C-CH (C
₆H_Five) -O-Si (CH_Three)_Three) Etc.
You.

The compound having an unsaturated bond includes an ethylenically unsaturated compound. Examples of the compound include ethylene, propylene, butadiene, isoprene, 1,4-dioxene,
1,4-dioxin is preferable, and particularly, the compound represented by the general formula II is preferable.

In the general formula II, R _{1 to} R ₆ represent hydrogen,
Represents an alkyl group which may have a substituent;
Represents an integer up to 4.

Further, as the ethylenic compound having a substituent, a compound represented by the above general formula III is also preferable. In the general formula III, R _{1 to} R ₃ represent hydrogen or an alkyl group which may have a substituent. X is -CH ₂ -
Or -CH (Y)-. Y represents a hydroxyl group, an epoxy group, a heterocyclic group, an alicyclic hydrocarbon group, or an alkyl group. n represents the integer of 0-4.

Examples of the heterocyclic ethylenically unsaturated compound include heterocyclic (meth) acrylates such as morpholine (meth) acrylate and tetrahydrofurfuryl (meth) acrylate.
Alkoxy (poly) alkylene glycol (meth) acrylates such as acrylates [eg, methoxyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, butoxypolyethylene glycol (meth) acrylate, etc.], alkylphenoxyethyl (meth) acrylate [ For example, nonylphenoxyethyl (meth) acrylate or the like], phenoxy (poly) alkylene glycol (meth) acrylate [for example, phenoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate or the like], alkyl (meth) acrylate [for example. Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, etc.], cycloalkyl (meth)
Acrylates [eg, cyclohexyl (meth) acrylate], aralkyl (meth) acrylates [eg, benzyl (meth) acrylate], di (meth) acrylates having an alicyclic hydrocarbon group [eg, isobornyl (meth) acrylate, Dicyclopentadiene (meth) acrylate, dicyclopentenyl (meth) acrylate, tricyclodecanyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, tricyclodecanyloxyethyl (meth) acrylate, isobornyloxy Ethyl (meth) acrylate, etc.), hydroxyl group-containing (meth) acrylate [for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3
-Chloro-2-hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth)
Acrylate, 2- (meth) acryloxyethyl-2-
Hydroxyethylphthalic acid, 3-acryloxyglycerin (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-1- (meth) acryloxy-3- (meth) acryloxypropane, polypropylene glycol mono (meth) Acrylate, glycerol mono (meth) acrylate, N, N, N-trimethyl N- (2-hydroxy-3-methacryloyloxypropyl) ammonium chloride, etc., epoxy group-containing (meth) acrylate [for example, glycidyl (meth)
Acrylate], halogen-containing (meth) acrylate [for example, trifluoroethyl (meth) acrylate,
2,2,3,3-tetrafluoropropyl (meth) acrylate, 2,2,3,4,4,4-hexafluorobutyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, etc.] . Y is particularly preferably a hydroxyl group or an epoxy group from the viewpoint of adhesiveness.

Compounds having two or more functional groups represented by the above general formula IV can also be preferably used.

In the general formula IV, R _{1 to} R ₃ represent hydrogen or an alkyl group which may have a substituent, Ra represents hydrogen or a hydroxyl group, and n represents an integer of 1 to 3. As specific compounds, di (meth) acrylate of 2,2-dimethyl-3-hydroxypropyl-2,2-dimethyl-3-hydroxypropionate, (polyoxy) alkylene glycol di (meth) acrylate [eg, ethylene glycol Di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (Meth) acrylate, 1,4-butanediol di (meth)
Acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentanediol di (meth) acrylate, etc.], glycerin di (meth) acrylate, trimethylolpropane di (meth) acrylate, penta Erythritol di (meth) acrylate, di (meth) acrylate of an alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of bisphenol A [for example, di (meth) acrylate of 2,2-bis (2-hydroxyethoxyphenyl) propane Acrylate), a di (meth) acrylate having a crosslinked alicyclic hydrocarbon group [eg, tricyclodecane dimethanol di (meth) acrylate, dicyclopentadiene di (meth) acrylate, etc.], Functional epoxy resin (meth) acrylic acid adduct [e.g., 2,2-bis (glycidyloxyphenyl) propane (meth) acrylic acid adduct], and the like. Examples of the compound with n = 3 include trimethylolpropane tri (meth) acrylate and trimethylolpropane trioxyethyl (meth)
Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (hydroxypropyl) isocyanurate Of tri (meth) acrylate, triallyl trimellitic acid, triallyl isocyanurate, and the like. These ethylenically unsaturated compounds can be used alone or in combination of two or more.

Among these ethylenically unsaturated compounds, a polymer film formed by plasma discharge treatment in a compound atmosphere containing a substituent having an oxygen atom, for example, a hydroxyl group, a carboxyl group, an epoxy group, etc., has an adhesion to a polarizer. This is preferable in that the polymer film can be formed even when the discharge treatment energy is small, and the treatment time can be shortened, so that the productivity can be increased.
Also, it was unexpected that a polymer coating formed of an unsaturated compound containing a hydrophilic group such as a hydroxyl group, a carboxyl group, or an epoxy group, when bonded to a polarizer, was less likely to contain air bubbles and provided a uniform bonded surface. It is presumed that it depends on the surface energy and the flexibility of the film. Examples of these particularly preferred compounds include acrylic acid, methacrylic acid, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and 2-hydroxypropyl (meth) acrylate.

Another example of a compound preferably used in the present invention is an organic compound containing nitrogen.
Compounds containing nitrogen include amino groups, amide groups,
Imino group, substituent such as cyano group, pyridine ring, pyrimidine ring, pyrazole ring, imidazole ring, pyrazine ring,
A compound containing a nitrogen-containing aromatic ring such as a triazole ring is preferable, and a compound represented by the above general formula V is particularly preferable.

In the formula, Rb represents H or various monovalent substituents, and Rb is bonded to an adjacent carbon atom C so that the nitrogen atom N and the carbon atom C form a double bond. 2
It may be a simple bond of valence. Z is a group of atoms necessary to complete a heterocyclic ring, and may have a substituent bonded thereto.

Examples of nitrogen-containing organic compounds include tricyclohexylamine, tribenzylamine, octadecylbenzylamine, stearylamine, allylurea, thiourea, methylthiourea, allylthiourea, ethylenethiourea, 2-benzylimidazole, 4-benzylimidazole, Phenylimidazole, 2-phenyl-4-methylimidazole, 2-undecylimidazoline, 2,4,5-trifuryl-2-imidazoline, 1,2-diphenyl-4,4
-Dimethyl-2-imidazoline, 2-phenyl-2-imidazoline, 1,2,3-triphenylguanidine,
1,2-dicyclohexylguanidine, 1,2,3-tricyclohexylguanidine, N, N'-dibenzylpiperazine, 4,4'-dithiomorpholine, 2-aminobenzothiazole, 2-benzoylhydrazinobenzothiazole, N- Vinylpyrrolidone, N-vinylpyridine,
N-vinyl heterocyclic compounds such as N-vinylcaprolactam, N-vinylacetamide, N-vinylformamide, dialkylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, N, N '-Dimethylacrylamide, and the like. These can be used in combination of two or more. Among these, when a nitrogen-containing compound having an unsaturated bond is used, the energy of the plasma discharge treatment is low and a polymer film can be formed, and bubbles are generated in the adhesiveness to the polarizer and in the adhesiveness to the polarizer. It is particularly preferable in terms of difficulty.

Further, in the present invention, a compound containing a volatile phosphorus (for example, vinylphosphonic acid, etc.)
The compound of the formula (1) is also preferably used.

In the present invention, when a polymer film is formed on a transparent substrate film by plasma discharge treatment in a reactive gas, the reactive gas preferably contains a gas containing an oxygen atom. Oxygen atoms are incorporated into the polymer film formed during the plasma discharge treatment, and are incorporated into the inside and the surface of the film as hydroxyl groups and carbonyl groups. For this reason, hydrogen bonds with polyvinyl alcohol are increased, and the adhesiveness and the adhesive durability are improved, which is preferable. The gas containing an oxygen atom is oxygen, ozone, carbon monoxide, or carbon dioxide, preferably oxygen, ozone, or carbon dioxide, and particularly preferably carbon dioxide from the viewpoint of safety. Further, when plasma discharge treatment is performed using a reactive gas containing a gas containing an oxygen atom and a compound having an unsaturated bond at the same time, a plasma discharge treatment is performed using an oxygen-containing gas after forming a polymerized film of a compound containing an unsaturated bond. A substituent containing an oxygen atom can be provided on or in many polymerized films. Therefore, by performing the treatment at the same time, it is possible to improve the adhesiveness and to simplify the process. As a preferable example of the unsaturated compound used simultaneously with the gas containing an oxygen atom, butadiene, isoprene and the like are particularly preferable in view of the rate of forming a polymer film.

The unsaturated compound and the nitrogen-containing compound of the present invention may be supplied as a reactive gas into a plasma discharge treatment atmosphere by heating and vaporizing the gas, or by heating or decompressing the material dissolved in a solvent. For example, a method of vaporizing and introducing by vaporization is used.

The thickness of the polymer film formed in the present invention is 0.1.
1 μm or less is preferable in terms of productivity. When the film thickness is large, the processing time is long, and the productivity is inferior. More preferably, it is 0.05 μm. Regarding the adhesion to the polarizer and the adhesion durability, there is no difference in performance even if the film is thinner. Rather, the thinner film is preferable because it is less likely to cause adhesion workability and bubbles and hardly cracks when bent. The film thickness is more preferably 0.01 μm or less, and the thinner the film, the higher the transparency. In the present invention, the transmittance for visible light is 90% or more.

The term “plasma discharge” refers to the generation of a plasma state by discharge. A plasma discharge treatment performed by applying a voltage to at least two opposing electrodes is preferred. The plasma discharge processing system according to the present invention is a processing space in which a plasma discharge is performed in the presence of a reactive gas, and specifically, a processing chamber separated by providing a partition with walls or the like. In the case of a vacuum plasma discharge treatment performed at a pressure of 0.007 hPa to 27 hPa close to a vacuum in the processing chamber, it is necessary to adjust the introduction of the reactive gas. In order to increase the processing speed, it is necessary to increase the voltage applied to the electrodes, but care must be taken because if the electric field intensity is too high, the object to be processed (eg, a base film) may be damaged. It is.

As a preferred embodiment, an atmospheric pressure plasma treatment in which the pressure in the processing chamber is at or near atmospheric pressure is preferable in terms of increasing productivity. As a gas introduced into the processing chamber, it is preferable to introduce an inert gas other than the reactive gas in order to generate a stable discharge.
Atmospheric pressure or near atmospheric pressure means 133 to 1064 hP
a, preferably 931 to 1037
hPa. The inert gas is a gas that does not react by plasma discharge itself, and includes an argon gas, a helium gas, a xenon gas, and a krypton gas. Among them, preferred gases are argon gas and helium gas. It is preferable that the ratio of the inert gas introduced into the processing chamber during the atmospheric pressure plasma treatment is 60% by pressure or more, which is larger than the reactive gas, because the discharge can be stably generated. The processing speed can be increased by increasing the applied voltage,
Care must be taken because an excessively high electric field strength may damage the object.

However, even in the case of the above-mentioned atmospheric pressure plasma processing, in the case where plasma is generated by a pulsed electric field, an inert gas is not always necessary, and the concentration of a reactive gas in the processing system may be increased. It becomes possible and production efficiency can be increased. The pulse waveform at this time is, for example,
A pulse waveform as shown in FIGS. 1 (a) to 1 (d) of JP-A-10-130851 is used.

The rise or fall time of the pulse electric field created between the electrodes by application of the pulse voltage is
It is preferable that both ranges from 40 ns to 100 μs and the intensity of the pulse electric field ranges from 1 to 100 kV / cm.

The frequency of the pulse electric field is 1 kHz to 1
It is preferable that the frequency is 00 kHz and the time for forming one pulse electric field is 1 μs to 1000 μs.

It is preferable that at least two opposing electrodes used in the atmospheric pressure plasma treatment have a solid dielectric on the opposing surface side. It is preferable to use sintered ceramics as the solid dielectric, and it is preferable that the volume specific resistance value is 10 ⁸ Ω · cm or more.

Further, when performing the plasma discharge treatment near the atmospheric pressure, it is preferable to generate a pulsed electric field by simultaneously applying different polar voltages to at least two opposing electrodes.

In the present invention, the object to be processed (base film) can be efficiently provided with an antistatic property by being placed between at least two opposing electrodes in the processing chamber. it can. In the case where a long film-shaped substrate is continuously transported, it is preferable to dispose the facing electrodes with a length on a line and to transport the gap therebetween.

FIG. 1 shows a long object to be processed (film-like substrate).
FIG. 1 schematically shows an embodiment of an apparatus for performing a continuous atmospheric pressure plasma discharge process.

The apparatus has a front chamber 10, an inlet 8 and an outlet 9, which can continuously introduce a processing gas (reactive gas).
It comprises a reaction chamber 2 provided with electrode groups 3 and 4 and a rear chamber (not shown) similar to the front chamber, and a processing object (a long film base material) is provided between the electrode groups in the reaction chamber. 1 can be continuously subjected to a plasma discharge process generated between the electrodes when the wafer 1 is transported.

In the present invention, as a more preferable plasma discharge treatment method, a method in which excited active species including plasma generated by glow discharge under atmospheric pressure is sprayed on a substrate to be treated is particularly preferable. In this method, the above-described reactive gas can be used. However, in this method, when processing is performed on a base film, the processing can be performed on one side at a time, and only by changing the reactive gas or gas conditions, the function can be achieved. Can be provided. For example, a configuration in which one side is an adhesive layer and another side is an antistatic layer, a configuration such as a hydrophilic layer / water repellent layer (antifouling layer), an antifouling layer / adhesive layer, and a low reflection layer / antistatic layer are exemplified. As another effect,
In an atmospheric pressure glow discharge sandwiched between electrodes, the object to be processed is easily damaged due to the presence of the object in the discharge space. On the other hand, the method in which the plasma is sprayed on the object does not easily damage the substrate. There is. In particular, cellulose acetate had a problem that the cellulose acetate became brittle due to the electron beam in the plasma discharge atmosphere in the atmospheric pressure glow discharge treatment sandwiched between the electrodes, but the method in which the plasma was sprayed on the workpiece significantly reduced the damage to the cellulose acetate. It was found that the surface treatment could be performed and the polymer film of the present invention could be formed efficiently. As another effect, when a polymer film is formed, the film forming speed can be controlled by the gas flow rate, so that an optical film can be manufactured without reducing productivity. Further, since single-sided processing is possible, an optical film having another function as described above can be manufactured on each side of the substrate.

Therefore, instead of applying a voltage to the two opposing electrodes described above and passing a base film between the opposing electrodes and subjecting the base film to a surface treatment, plasma is contained under such atmospheric pressure. A method of treating a substrate film by spraying an excited active species onto a treated substrate is also useful.

FIG. 2 is a schematic diagram showing an example of a surface treatment apparatus for treating an object to be processed (film substrate) by spraying excited species including plasma under atmospheric pressure. An alternating current is applied by a power supply 14 between the electrodes of a tubular reaction tube 11 having an outer electrode 12 on the outside and an inner electrode 13 on the inside (the electrode has a cooling water inlet 13a and an outlet 13b for cooling), By generating a glow discharge inside the reaction tube 11, the processing gas introduced from the inlet 16 is made into an excited active species including plasma, and is blown from the lower blowing port 17 to the workpiece.

In the method of the present invention in which excited active species including plasma are sprayed on the treated substrate, the degree of the antistatic property of the substrate film, for example, when an optical film having an antistatic property on one surface is produced. By changing the gas conditions of the processing system (gas type, gas concentration, gas sealing conditions, pressure, etc.), electric field strength, discharge conditions, and the like, the control can be conveniently performed. The absolute value of the impedance at a frequency of 20 Hz is 4 × 10 ⁵
It is preferably Ω or more. Further, the surface specific resistance of the optical film is preferably 1 × 10 ¹² Ω / cm ² or less. The method described later is used for the impedance measurement method.

The surface resistivity was measured by the following method. The sample to be measured was conditioned at 23 ° C. and 55% RH for 24 hours, and measured using a Teraohmmeter model VE-30 manufactured by Kawaguchi Electric Co., Ltd. The electrodes used for the measurement were two electrodes (the part in contact with the sample was 1c
m × 5 cm) were arranged in parallel at an interval of 1 cm, the sample was brought into contact with the electrode, and measured. The value obtained by doubling the measured value was defined as the surface resistivity Ω / cm ² .

The reactive gas used for forming these layers having antistatic properties on a substrate film (a conductive layer (provided in the present invention that a conductive layer is formed on a substrate film by plasma discharge). Is a gas that can form), specifically, a gas containing a metal compound containing indium, zinc, tin, titanium, etc., oxygen, carbon monoxide, carbon dioxide, nitrogen monoxide, nitrogen dioxide. , Hydrogen peroxide and ozone, and a gas that can react with the base film and the metal-containing compound.

In order to generate a stable discharge, it is preferable to introduce an inert gas other than the reactive gas.

As the metal compound-containing gas described above, an organic compound containing indium, zinc, tin, titanium and the like is preferably used. In particular, zinc acetylacetonate, triethyl indium, trimethyl indium, diethyl zinc, dimethyl zinc, tetraethyl tin, tetramethyl tin, dibutyl tin diacetate, tetrabutyl tin, and the like are preferable, and gas is passed through these liquids or solutions and generated by bubbling. It is preferable because it can be performed. When the gas for bubbling is the reactive gas such as oxygen, carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, hydrogen peroxide or ozone or the inert gas, the reactive gas is efficiently prepared. This is particularly preferred because When the solution to be bubbled is triethylindium, diethylzinc, or dimethylzinc, it is safe to use carbon dioxide due to the problem of ignitability.

The conductive layer according to the present invention is formed by plasma discharge in the presence of the above-mentioned substrate film and the above-mentioned reactive gas. A layer in which a substance and an organic component are mixed and exhibiting conductivity means that the film having the conductive layer according to the present invention has an absolute value of impedance of 4 × 10 ⁵ Ω or more at a frequency of 20 Hz. Say.

As is known, the antistatic property of a material is exhibited by a cation, an anion, or a charge carrier such as an electron or a hole present in a particle. When the main charge carrier is an ion, it becomes a solid electrolyte, and when the charge carrier is an electron, it becomes a semiconductor. In addition, a detailed study of the conductivity reveals that, generally, as the conductivity of the material increases, the absolute value of the impedance Z including the resistance term decreases as shown in the following known formula. Have been.

| Z | = [R ² + (1 / ωC) ² ] ^1/2 where Z: impedance R: resistance, C: capacitance, ω: 2πf, f: frequency Regarding the impedance measurement, a general impedance measurement device used for measuring the permittivity of an electronic component can be used, but preferably, an impedance measurement device capable of measuring a frequency of 1 Hz or more and a film measurement electrode are combined. .
For example, Precision L manufactured by Hewlett-Packard Company
This is a combination of the CR meters HP4284A and HP16451B. When using another device, it is necessary to correct the electrode portion. In order to achieve the present invention, it is necessary to correctly measure the impedance of the film material. Therefore, when an uncorrectable device is used, a favorable result cannot be obtained. 20Hz more with this device combination
An example of obtaining the absolute value of the impedance in the following is described in detail below. However, the present invention does not limit the measuring method as long as the accurate absolute value of the impedance of the film material at a frequency of 20 Hz can be measured.

Using a precision LCR meter HP4284A connected to an HP16451B having two electrodes composed of parallel planes and a guard electrode, at 23 ° C. and 55%
Under an RH atmosphere, the absolute value of the impedance of the film material is measured by a gap method. Regarding the measurement of the void method,
Follow the electrode non-contact method described in the instruction manual of HP16451B. The size of the sample is not particularly limited as long as it is larger than the electrode plane, but when the diameter of the main electrode is 3.8 cm, the size is 6 cm × 6 cm to 5 c.
A square sample of mx 5 cm is preferred. If the surface resistivity measured using the direct current of the sample is the same on the front and back, either side may be placed on the upper side. A sample is placed between two electrodes composed of parallel planes, and measurement is performed by the air gap method while applying an AC voltage. The measured range is preferably such that the absolute value of the impedance at a frequency of 20 Hz is 4 × 10 ⁵ Ω or more, preferably 4 × 10 ⁵ Ω.
10 ⁵ to 1 × 10 ²⁰ Ω, more preferably 5 × 10 ⁵ to 1 ×
10 ¹⁴ Ω. The surface resistivity is 1 × 10 ¹² Ω /
cm ² or less (23 ° C., 55% RH), more preferably 5 × 10 ¹¹ Ω / cm ² or less (23 ° C., 55% RH).
RH).

As described above, an optical film provided with an antistatic layer can be manufactured by a method in which plasma generated by glow discharge under atmospheric pressure is sprayed onto a target object. Similarly, for example, in the apparatus shown in FIG. 2, an easily adhesive layer, a structure in which another surface is an antistatic layer, a hydrophilic layer / water repellent layer (antifouling layer), an antifouling layer / adhesive layer, and a low reflection layer / Layers with different functions such as antistatic layer, the type of reactive gas, composition, etc.
It can be applied to the substrate film only by changing the gas conditions, thereby making it possible to produce optical films having various functions.

Further, as one embodiment of the present invention, the optical film of the present invention can be used for protecting an image by an ink jet system, which will be described in detail below.

In recent years, inkjet printing has become widespread as heart copy. In particular, ink jet recording paper from which high-quality images are selected has come to be widely used. Above all, an ink jet recording paper in which ink absorption is improved by a layer having a void is generally one in which a void is formed by fine particles and an ink receiving layer is formed using a hydrophilic binder. The present inventors paid attention to the properties of the hydrophilic binder of the ink jet recording paper, and protected the film on which the plasma-treated hydrophilic polymer layer according to the present invention capable of forming hydrogen bonds with the hydrophilic binder was formed. It has been found that the film can be adhered to the ink jet recording paper, thereby improving the problems of the ink jet recording paper. In particular, it has good adhesiveness when a transparent film is bonded to the ink absorbing layer, prevents oxidative discoloration due to oxygen, improves image preservability, and prevents image bleeding due to moisture and the like. it can.

In the present invention, the polymer layer provided on the transparent substrate film is used as an adhesive layer,
The transparent film is bonded through the adhesive layer, and an image is viewed from the transparent film side. As the film used for the transparent film, the transparent film described above can be used.

The adhesive layer may be provided with an adhesive layer by saponifying or coating the above-mentioned transparent film with an alkali, or an adhesive layer by plasma discharge treatment, but is preferably formed by plasma discharge treatment in terms of film productivity. .

As the plasma treatment, there are methods such as vacuum glow discharge and atmospheric pressure glow discharge as described above.
2, Japanese Patent Application No. 10-97426, Japanese Patent Application No. 10-944
No. 68, it can be used by a method similar to the method described in further detail above, to form a polymer film on the transparent substrate film surface by plasma treatment to impart hydrophilicity be able to. Above all, those based on atmospheric pressure glow discharge are preferably used. As for the atmospheric pressure glow discharge, a method using an opposing electrode and a method in which plasma generated by the glow discharge is blown onto the object to be processed can be used as described above.

The gas used for the plasma processing includes
A hydrophilic surface can be obtained on a transparent substrate by adding a reactive gas such as hydrogen, oxygen, nitrogen, water vapor, carbon dioxide, ozone, carbon monoxide, or ammonia to an inert gas such as argon or helium. . Further, there is a method of forming a polymer film by adding a polymer compound to the reactive gas. The method for forming the polymer film is the same as the method described in detail above.

As an example of the adhesive layer formed by coating, see
As described in JP-A-6-94915, JP-A-06-118252, JP-A-07-333436, and JP-A-08-96801, a polymer compound having a -COOM group in a transparent substrate film is preferable. Is provided, and a layer containing a hydrophilic polymer compound as a main component is provided on the polarizing film side adjacent to the layer.
Examples of the polymer compound include a styrene-maleic acid copolymer having a -COOM group, a vinyl acetate-maleic acid copolymer having a -COOM group, and a vinyl acetate-maleic acid-maleic anhydride copolymer. -COOM
It is preferable to use a vinyl acetate-maleic acid copolymer having a group. As the hydrophilic polymer compound, preferably, a hydrophilic cellulose derivative (eg, methyl cellulose, carboxymethyl cellulose, hydroxycellulose, etc.), a polyvinyl alcohol derivative (eg, polyvinyl alcohol, a vinyl acetate-vinyl alcohol copolymer, polyvinyl acetal, polyvinyl formal) , Polyvinyl benzal, etc.), natural polymer compounds (for example,
Gelatin, casein, gum arabic, etc.), hydrophilic polyester derivatives (eg, partially sulfonated polyethylene terephthalate, etc.), hydrophilic polyvinyl derivatives (eg, poly-N-vinylpyrrolidone, polyacrylamide, polyvinylindazole, polyvinylpyrazole) And the like, and used alone or in combination of two or more.

The optical film used for protecting the image of the ink jet recording paper may also be one having an antistatic layer or the like formed on the other surface in addition to the adhesive layer by the method described above.

The ink jet recording paper used together with the optical film of the present invention has a void layer containing fine particles as an ink absorbing layer, and preferably contains fine particles having an average particle diameter of 100 nm or less. As the fine particles, various kinds of inorganic or organic solid fine particles conventionally known in ink jet recording paper can be used. Examples of inorganic fine particles include light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc hydroxide, zinc sulfide, zinc carbonate, hydrotalcite. , Aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, alumina, colloidal alumina, pseudoboehmite, aluminum hydroxide, lithopone, zeolite, white inorganic pigments such as magnesium hydroxide and the like. Can be done. Examples of the organic fine particles include polystyrene, polyacrylates, polymethacrylates, polyacrylamides, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, or a copolymer thereof, a urea resin, or Melamine resins and the like can be mentioned. In particular, silica fine particles are preferably used as the fine particles in terms of achieving a high density, recording a clear image, and being able to be manufactured at low cost.

In the case of ink-jet recording paper, in order to contain fine particles in the ink absorbing layer and form voids,
It is necessary to include a hydrophilic binder in the layer in order to form a stable film. As the hydrophilic binder used, gelatin or a gelatin derivative, polyvinylpyrrolidone, pullulan, polyvinyl alcohol or a derivative thereof, polyethylene glycol, carboxymethylcellulose, hydroxyethylcellulose, dextran, dextrin, polyacrylic acid and a salt thereof, agar, κ-carrageenan, λ-carrageenan, ι-
Carrageenan, xanthene gum, locust bean gum, alginic acid, gum arabic, JP-A-7-19582
Nos. 6 and 7-9957, polyalkylene oxide copolymerizable polymers, water-soluble polyvinyl butyral, and vinyl monomers having a carboxyl group or a sulfonic acid group described in JP-A-62-245260. Or a polymer such as a copolymer having these vinyl monomers repeatedly. These hydrophilic binders may be used alone or in combination of two or more. Among them, using a hydrophilic binder containing polyvinyl alcohol,
It is preferable because the film has a hygroscopic property, is sticky under high humidity, and has little bleeding of the dye during ink jet recording. The polyvinyl alcohol includes cationically modified, nonionicly modified, and anionicly modified polyvinyl alcohols.

The average degree of polymerization of polyvinyl alcohol is preferably from 1,000 to 5,000 from the viewpoint of film-forming properties, and particularly preferably the average degree of polymerization is 2,000 or more. The degree of saponification of polyvinyl alcohol is 70 to 10
0% is preferred, and 80-100% is particularly preferred.

[0119]

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

Example 1 << Preparation of Resin Film 1 >> (Preparation of Dope Composition (1)) Cellulose triacetate (average degree of oxidation: 61.0%) 85 kg Cellulose acetate propionate (degree of acetyl group substitution 2.0, propionyl) Degree of group substitution 0.8) 15 kg Triphenyl phosphate 5 kg Ethylphthalylethyl glycolate 2 kg Tinuvin 109 0.5 kg Tinuvin 117 0.5 kg Tinuvin 326 0.3 kg Ultrafine silica (Aerosil 200V: manufactured by Nippon Aerosil Co., Ltd.) 0 0.01 kg methylene chloride 430 kg methanol 90 kg The above composition was charged into a closed container, kept at 80 ° C. under pressure, and completely dissolved with stirring to obtain a dope composition. Next, this dope composition was filtered, cooled and kept at 35 ° C., and was uniformly cast on a stainless steel band. When the solvent was evaporated until peeling was possible, the dope composition was separated from the stainless steel band. In the drying zone between 50% by mass and 5% by mass of the residual solvent after the peeling, the drying proceeds while maintaining the width by the tenter, and further, while being conveyed by a number of rolls, until the residual solvent amount becomes 1% by mass or less. Dry, film thickness 80
A μm film was obtained.

The resin film 1 and <resin film 2> uniaxially stretched polyethylene terephthalate film (manufactured by Toyobo Co., Ltd.), and <resin film 3> polylactic acid film (weight average molecular weight 140000) manufactured by Unitika Ltd. Adhesion between the polyvinyl alcohol (PVA) layer and the plasma-treated surface of the film sample was determined using the film sample subjected to the plasma discharge treatment (the reactive gas and the inert gas used in the treatment are described in Table 1) under the conditions shown in Table 1. The evaluation was performed according to the method described in

<PVA Adhesion> Polyvinyl alcohol NH-17 manufactured by Nippon Synthetic Chemical Co., Ltd. (polymerization degree: 1500 or more, saponification degree: 98 to 99 mol%) is dissolved in warm water, and then coated with a bar coater on a transparent substrate film. 80 ° C
And dry for 30 minutes. The thickness of the formed polyvinyl alcohol layer is adjusted to 0.5 μm ± 10%. The evaluation of the adhesion of this polyvinyl alcohol layer is based on JIS K-540.
According to the crosscut tape method of 0, the specified cutter knife,
Using a cutter guide, 100 squares are formed at 1 mm intervals, and a specified cellophane adhesive tape is attached thereto and rubbed with an eraser to adhere to the coating film. Two minutes after application of the tape, it is momentarily peeled off in the direction perpendicular to the coated surface. It was represented by the number of grids remaining without peeling out of the 100 grids. The results are shown in Table 1.

[0123]

[Table 1]

(Plasma discharge processing condition 1) Power output: 8000 W / m ² Processing gas: inert gas / reactive gas = 8/2 (pressure ratio)
The flow rate was controlled by a mass flow controller so as to achieve the ratio described above, and the mixture obtained by the mixer was introduced into the processing chamber.

Processing time: 35 seconds Apparatus 1: continuous atmospheric pressure plasma discharge processing apparatus (schematic diagram shown in FIG. 1) Power supply: Shinko Electric Co., Ltd. high frequency power supply SPG05-4500 Power supply frequency: 5 kHz (sine wave type) (plasma discharge Processing condition 2) Power output: 8000 W / m ² Processing gas: Same as plasma discharge processing condition 1 Processing time: 35 seconds Apparatus 2: Continuous atmospheric pressure plasma discharge processing apparatus (schematic diagram shown in FIG. 1) Power supply: Heiden Kenkyusha PHF-4K power supply frequency: 10 kHz The power supply was changed to an impulse type.

(Plasma discharge processing condition 3) Power output: 8000 W / m ² Processing gas: Same as plasma discharge processing condition 1 Processing time: Plasma blowing time was set to 15 seconds Apparatus 3: Processing excited active species including plasma Apparatus for spraying on substrate (schematic diagram shown in FIG. 2) Surface energy polar components Ocl / Ocs, Ncl / N
It can be seen that when the cs and Pcl / Pcs values are at high levels, the adhesion to PVA is good. Accordingly, when the protective film is a polarizing plate protective film, the adhesiveness to the polarizer is good.

Example 2 Resin films 1 to 3 used in Example 1 and Example 1
On the surface opposite to the surface-treated surface (A surface) of the film sample (described as a film to be treated in Table 2) prepared in
Samples 201 to 211 that were subjected to plasma discharge processing under the plasma processing conditions 4 shown below were produced (the surface subjected to the plasma processing is referred to as surface B). Table 2 shows the results of the evaluation of the impedance, the surface resistivity of the surface B, and the adhesion of dust to the surface B.
It was shown to.

<Measurement of Impedance>
Packard Precision LCR Meter HP428
20Hz using the combination of 4A and HP16451B
Was measured. More specifically, an HP16 having a two-electrode formed of parallel planes and a guard electrode
451B connected precision LCR meter HP
Using 4284A, it measured at 23 degreeC and 55% RH atmosphere.

<Surface Resistivity> Each sample was heated at 23 ° C. and 55 ° C.
The humidity was controlled for 24 hours under the condition of% RH, and the measurement was performed using a Teraohmmeter model VE-30 manufactured by Kawaguchi Electric Co., Ltd. The electrodes used for the measurement were measured by placing two electrodes (the part in contact with the sample was 1 cm × 5 cm) in parallel at an interval of 1 cm, contacting the sample with the electrode, and measuring the value five times. The value was defined as a surface resistivity value Ω / cm ² .

<Adhesion of Dust> A film sample of 10 cm ×
Cut out to 20 cm, rub each side of B side 20 times with tissue paper, bring the B side of the film close to the height of 1 cm for 10 seconds to the ash of cigarette, observe the adhesion of dust (ash), and evaluate the rank on a three-point scale Was done.

：: No dust adhesion was observed at all Δ: Dust adhesion was slightly observed ×: Dust adhesion was observed differently

[0132]

[Table 2]

(Plasma discharge processing condition 4) Power output: 8000 W / m ² Processing gas: Argon gas / reactive gas = 8/2 (pressure ratio) The flow rate was controlled by a mass flow controller, and the flow rate was controlled by a mixer. The mixture was introduced into the processing chamber.

Reactive gas: Zinc acetylacetonate heated to 100 ° C. was prepared by passing oxygen.

Processing time: The time for spraying plasma on the film surface was adjusted to 35 seconds. Apparatus 3: Apparatus for spraying excited active species including plasma onto the processing substrate (schematic diagram shown in FIG. 2) According to these, a conductive layer can be efficiently applied to one surface of the substrate film. It is possible to produce a film having good PVA adhesion and conductivity.

Example 3 Sample No. 1 of Example 1 101 to 116 and the sample Nos. Nos. 204 to 211 were used, and Sample Nos. Of these two films were used. Regarding 101 to 116, the plasma treated surface and the sample No. Regarding 204 to 211, a polyvinyl alcohol adhesive (3% aqueous solution, dry film thickness: 0.01 μm) was applied to the A side, and a polarizer produced as described below was bonded to produce a polarizing plate. No. 1
The adhesiveness of the polarizing plates prepared from samples other than Sample No. 01 was good. Even when the polarizing plate was stored at 80 ° C. and 90% for 2 weeks under a dry condition at 100 ° C., no change was observed in the adhesiveness of the polarizing plate. In addition, sample No. The evaluation of dust adhesion of the polarizing plate prepared from 204 to 210 was ○.

<Preparation of Polarizer> A 75 μm thick PVA film (Kuraray Vinylon # 7500; manufactured by Kuraray Co., Ltd.) was uniaxially stretched longitudinally (stretching ratio 4 times) to obtain a polarizer base material. This base material was washed with 0.2 g / l of iodine and 30 g of potassium iodide.
/ L of an aqueous solution at 30 ° C for 4 minutes. Then, it is immersed in an aqueous solution having a composition of boric acid 70 g / l and potassium iodide 30 g / l at 55 ° C. for 5 minutes, and further immersed in water at 20 ° C. for 3 minutes.
After washing for 0 second, drying was performed to obtain a polarizer.

Example 4 An in-plane switching (IPS) active liquid crystal display device was manufactured by the method described in the example of JP-A-11-264982 as follows. However, the polarizing plate used was the polarizing plate of Example 3 (manufactured using No. 204 of Example 2).

First, a cover sheet made of polyethylene was attached to both surfaces of the polarizing plate to prevent scratches. Next, the polyethylene cover sheet on one side was peeled off and attached to a liquid crystal glass substrate to produce a liquid crystal panel. When the polyethylene cover sheet on the surface of the liquid crystal panel was peeled off, there was no disturbance of the liquid crystal. On the other hand, when a polarizing plate having no conductive layer was used, the liquid crystal was disturbed. In addition, no dust adhered to the liquid crystal panel using the polarizing plate having the conductive layer formed thereon.

Example 5 Low-density polyethylene having a density of 0.92 and a thickness of 30 μm were applied to the back surface of a photographic base paper having a water content of 6% by mass and a basis weight of 170 g / m ^{2 by} an extrusion coating method. Then, low-density polyethylene containing 5.5% by mass of anatase-type titanium oxide and having a density of 0.92 was applied to the front side with a thickness of 35 μm by extrusion coating to prepare a support having both surfaces coated with polyethylene. Corona discharge was applied to the front side to form a gelatin undercoat layer of 0.3 g / m ² , and corona discharge was applied to the back side, and then a latex layer was applied to a thickness of 0.2 g / m ² . Further, after applying the coating solution-1 having the following composition on the front side, the coating temperature is rapidly cooled within 30 seconds so that the coating temperature becomes 15 ° C. or less, and rapidly dried in a wind of 20 to 50 ° C. for 2 minutes. Thus, an ink jet recording paper having a void layer having a dry film thickness of 20 μm was produced. The obtained recording paper is 36
C. for 3 days to harden. When the cross section of the void layer of this recording paper was observed with an electron microscope, the average particle size of the primary particles was 12 nm, and the average particle size of the secondary aggregated particles was 65 nm.

(Coating liquid-1) Fine particle silica dispersion * 450 ml Cationic polymer (P-1) 2 g Ethanol 35 ml n-propanol 10 ml Ethyl acetate 5 ml Polyvinyl alcohol (PVA203 manufactured by Kuraray Co., Ltd.) 0.1 g Polyvinyl alcohol (Kuraray stock) 12 g boric acid 2.0 g borax 1.0 g <fine particle silica dispersion> 80 g of A200 manufactured by Nippon Aerosil Co., Ltd. (vapor-phase silica having an average primary particle diameter of 12 nm) is added to 400 ml of pure water. After that, the whole amount was adjusted to 450 ml with pure water.

[0142]

Embedded image

The obtained recording paper was evaluated for the light fading property of the image by the following method. Seiko Epson Inkjet Printer PM-750C, Y,
M and C wedge images were printed. Sample No. of Example 1 110 and the sample Nos. A polyvinyl alcohol adhesive (3% aqueous solution, dry film thickness 0.01 μm) was applied to the A side of 209, and a wedge image was attached to the printed image, and then dried at 80 ° C. for 2 minutes to be adhered.

Each of them was irradiated with light using a xenon lamp for 100 hours using a light resistance tester manufactured by Suga Test Instruments Co., Ltd., and the dye remaining ratio (light resistance) at an initial density of 1.0 was examined.

Dye residual rate = 100 × (density after light irradiation)
/ (Initial concentration) (measured at an initial concentration of 1.0). The sample on which the film of the present invention was not applied,
Whereas the residual ratio of the magenta dye was 32%, those to which the film of the present invention was applied were 98% and 99%, respectively.
And most of the dye remained.

[0146]

According to the present invention, the work is safe and does not adversely affect the environment.
By performing surface treatment capable of forming a layer having excellent adhesion with a polyvinyl alcohol or a polyvinyl alcohol-containing layer on a base film, an optical film suitable for a protective film for a polarizing plate, an antistatic film, or the like can be obtained. Done
In addition, a polarizing plate and a liquid crystal display using these can be provided. Further, an image display material which is more excellent in adhesiveness to an ink jet recording paper as a laminating film and which can improve the preservability of an image integrally therewith can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating one embodiment of an apparatus for performing an atmospheric pressure plasma discharge process.

FIG. 2 is a schematic configuration diagram illustrating an embodiment of an apparatus for spraying excited active species including plasma onto a target object.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 film substrate (object to be processed) 2 reaction chamber 3, 4 electrode 5 power supply 6 ground 7 nip roll 8 processing gas inlet 9 processing gas outlet 10 front chamber 20, 21, 22 transport roll L electrode spacing 11 reaction tube DESCRIPTION OF SYMBOLS 12 External electrode 13 Internal electrode 13a Cooling water inlet 13b Cooling water outlet 14 Power supply 15 Ground 16 Processing gas inlet 17 Excited active species spray port

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G09F 9/00 313 G02B 1/10 Z F term (reference) 2H049 BA02 BB22 BB23 BB27 BB28 BB33 BB43 BB51 BC14 BC22 2H091 FA08X FA08Z FA11X FA11Z FA50X FA50Z FB02 FB12 FC27 FD14 GA16 LA01 LA07 LA09 2K009 BB11 BB14 BB24 BB28 DD17 EE00 FF03 5G435 AA03 AA14 BB12 FF00 FF05 GG42 KK05

Claims (36)

[Claims] 1. A polar component having a surface energy of 10.0 mN / m on a surface of a transparent substrate film to which a polarizer is adhered.
A protective film for a polarizing plate, comprising a layer having a thickness of 0.1 μm or less as described above and having a transmittance of 90% or more. 2. A protective film for a polarizing plate having a layer having a thickness of 0.1 μm or less on a surface of a transparent substrate film to which a polarizer is adhered, and having a transmittance of 90% or more.
oxygen, nitrogen to carbon on the surface of the layer below μm,
The element ratios of phosphorus are Ocl, Ncl, and Pcl, and the element ratios of oxygen, nitrogen, and phosphorus to carbon on the surface of the base film excluding the layer having a thickness of 0.1 μm are Oc, respectively.
When expressed as s, Ncs, Pcs, Ocl / Ocs, N
A protective film for a polarizing plate, wherein any one of cl / Ncs and Pcl / Pcs is 1.1 or more. 3. A protective film for a polarizing plate having a layer having a thickness of 0.1 μm or less on a surface of a transparent substrate film to which a polarizer is adhered and having a transmittance of 90% or more.
When polyvinyl alcohol (polymerization degree 1500 or more, saponification degree 98 to 99 mol%) is further applied on the layer having a thickness of 0.1 μm or less,
A protective film for a polarizing plate, wherein the number of grids remaining without being peeled off is 90 or more when the grid tape method conforming to JIS K-5400 is used for adhesion to the following layers. . 4. A layer having a thickness of 0.1 μm or less is formed by subjecting a transparent substrate film to plasma discharge treatment in a reactive gas atmosphere containing an organic compound. The protective film for a polarizing plate according to any one of claims 1 to 3. 5. The protective film for a polarizing plate according to claim 4, wherein the organic compound is a compound having an unsaturated bond. 6. The protective film for a polarizing plate according to claim 5, wherein the compound having an unsaturated bond is a compound having at least a substituent selected from a hydroxyl group, a carbonyl group, a carboxyl group, and an epoxy group. . 7. The protective film for a polarizing plate according to claim 5, wherein the compound having an unsaturated bond is at least a compound selected from formulas I to IV. Embedded image (In the formula, R ₁ and R ₂ represent hydrogen or an alkyl group, and the alkyl group may have a substituent.) (In the formula, R _{1 to} R ₆ represent hydrogen or an alkyl group, and the alkyl group may have a substituent. N represents an integer of 0 to 4.) (Wherein, R _{1 to} R ₃ represent hydrogen or an alkyl group, and the alkyl group may have a substituent. X is CH ₂ or CH
Represents -Y. Y represents a hydroxyl group, an epoxy group, a heterocyclic group, an alicyclic hydrocarbon group, or an alkyl group. n is 0 to 4
Represents an integer. ) (In the formula, R _{1 to} R ₃ represent hydrogen or an alkyl group, and the alkyl group may have a substituent. Ra represents hydrogen or a hydroxyl group, and n represents an integer of 1 to 3.) 8. The protective film for a polarizing plate according to claim 4, wherein the organic compound is a compound having a nitrogen atom. 9. The protective film for a polarizing plate according to claim 8, wherein the compound having a nitrogen atom is at least a compound selected from general formula V. Embedded image (In the formula, Rb represents H or a monovalent substituent.
May bond to an adjacent carbon atom C, and the nitrogen atom N and the carbon atom C may serve as a mere divalent bond for forming a double bond. Z is a group of atoms necessary to complete a heterocyclic ring, and may have a substituent bonded thereto. ) 10. The polarizing plate protective film according to claim 4, wherein the reactive gas used in the plasma discharge treatment further contains a gas containing an oxygen atom. 11. The polarizing plate according to claim 1, wherein a cellulose ester film, a polycarbonate film, a polyester film, a polylactic acid or a polyacryl film is used as the transparent substrate film. Protective film. 12. The air pressure is set at 0 in plasma discharge processing.
The protective film for a polarizing plate according to any one of claims 4 to 11, wherein the pressure is 007 to 27 hPa or less. 13. The plasma discharge process according to claim 4, wherein the plasma discharge process is performed at or near atmospheric pressure.
2. The protective film for a polarizing plate according to claim 1. 14. The protective film for a polarizing plate according to claim 13, wherein at least one of the electrodes used for the plasma discharge treatment has a solid dielectric. 15. The protective film for a polarizing plate according to claim 13, wherein the reactive gas used for the plasma discharge treatment further contains an inert gas. 16. The protective film for a polarizing plate according to claim 15, wherein the inert gas is an argon gas or a helium gas. 17. The protective film for a polarizing plate according to claim 13, wherein a pulse-like voltage is applied between the plasma discharge electrodes. 18. A pulse electric field generated between electrodes by application of a pulse-like voltage has a rise or fall time in a range of 40 ns to 100 μs and a pulse electric field strength of 1 to 100 kV / cm. The protective film for a polarizing plate according to claim 17, which is within the range. 19. The frequency of a pulse electric field is 1 kHz to 10 kHz.
The protective film for a polarizing plate according to claim 18, wherein the frequency is 0 kHz, and one pulse electric field is formed in a time of 1 µs to 1000 µs. 20. The protective film for a polarizing plate according to claim 18, wherein a pulse electric field is generated by simultaneously applying different polar voltages to at least two opposing electrodes. 21. An inert gas or a mixed gas of an inert gas and a reactive gas is introduced into a slit-shaped reaction tube having an outer electrode and a reaction tube of a plasma processing apparatus having an inner electrode inside the reaction tube; An optical field characterized by applying an AC electric field between the outer electrode and the inner electrode to generate excited active species including plasma, and performing a surface treatment by spraying the excited active species onto a transparent substrate film. the film. 22. A reaction gas containing an inert gas or an inert gas and a metal element-containing compound in a slit-shaped reaction tube having an outer electrode and a reaction tube of a plasma processing apparatus having an inner electrode inside the reaction tube. By applying an AC electric field between the outer electrode and the inner electrode to generate excited active species including plasma, and performing the surface treatment by spraying the excited active species onto the transparent substrate film. Characteristic optical film. 23. The optical film according to claim 22, wherein the absolute value of the impedance at a frequency of 20 Hz is 4 × 10 ⁵ Ω or more. 24. The optical film according to any one of claims 21 to 23, wherein the transparent substrate film is cellulose acetate. 25. The optical film according to claim 21, which is used as a protective film for a polarizing plate, a retardation film, or a brightness enhancement film. A polarizing plate comprising the optical film according to any one of claims 21 to 24. 27. A liquid crystal display using the optical film according to claim 25. 28. A liquid crystal display using the polarizing plate according to claim 26. 29. A polarizing plate comprising the protective film for a polarizing plate according to claim 1 and a polarizer made of polyvinyl alcohol. 30. A method for producing a polarizing plate, comprising: washing the polarizing plate protective film with water before laminating the polarizer protective film according to claim 1 with a polarizer comprising polyvinyl alcohol. . 31. A transparent substrate film having a layer formed by plasma discharge treatment in a reactive gas atmosphere or by spraying excited active species containing plasma, comprising at least polyvinyl alcohol having an image formed thereon. A method for improving image storability, comprising laminating an image display material having a layer on a support. 32. A transparent substrate film having a layer formed by plasma discharge treatment in a reactive gas atmosphere or by spraying excited active species containing plasma, and at least polyvinyl alcohol on which an image has been formed. An image display material having improved image storability, wherein the image display material has been laminated with an image display material having a layer on a support. 33. The method according to claim 31, wherein the transparent substrate film is a cellulose ester film, a polycarbonate film, or a polyester film. 34. The image display material according to claim 32, wherein the transparent substrate film is a cellulose ester film, a polycarbonate film, or a polyester film. 35. The image display material having at least a layer containing polyvinyl alcohol on a support is an ink jet recording paper.
3. The method for improving image storability according to item 3. 36. The image display material having at least a layer containing polyvinyl alcohol on a support is an ink jet recording paper.
The image display material described in 1.