JPH11105205A - Plastic film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plastic film having excellent light transmission properties and adhesion. SOLUTION: A plastic film is composed by providing at least one layer containing a layer formed of a coating liquid containing at least two types of acrylic polymer latex. In at least two acrylic polymer latex, the temperature difference between glass transition temperature (TgL) of the acrylic polymer latex showing lowest glass transition temperature, and glass transition temperature (TgH) of the acrylic polymer latex showing highest glass transition temperature is 10-80 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic film having improved adhesiveness, and more particularly to a highly processed product of the film, for example, a magnetic tape for audio, a magnetic tape for video, a magnetic tape for computer, a floppy disk, Photographic films, printing materials, medical materials,
The present invention relates to a plastic film having excellent adhesiveness, which is useful as a base material for telephone cards, membranes, diazo microfilms and the like.

[0002]

2. Description of the Related Art A thermoplastic polyester such as polyethylene terephthalate or a copolymer thereof, a polyethylene naphthalate or a copolymer thereof, or a blend thereof with a small proportion of another resin is melt-extruded to form a film. A biaxially stretched and heat-set polyester film has been produced by axially stretching and heat-setting. It is also known that these biaxially stretched and heat-set polyester films are superior in heat resistance, gas barrier properties, electrical properties and chemical resistance to films made of other resins.

[0003] However, since the surface is highly crystallographically oriented, the surface has high cohesiveness.
Poor adhesion to adhesives, inks, etc.

[0004] Therefore, the polyester film which has been biaxially stretched and heat-set is subjected to a physical treatment such as corona treatment, ultraviolet treatment, plasma treatment, EB treatment or flame treatment, or a chemical treatment such as alkali, amine aqueous solution, trichloroacetic acid, or the like. It has been practiced to improve the adhesiveness by treating with a chemical such as phenols.

[0005] However, when these treatment methods are used, there is a practical problem in that the adhesive force is deteriorated with time or the working environment is contaminated by evaporation of the chemical.

As another means for improving the adhesiveness of a biaxially stretched and heat-set polyester film, a primer is applied to the film surface by a process other than the ordinary polyester film forming process to provide easy adhesion. A method of providing a primer layer is known.

However, in this method, usually, an organic solvent is used as a solvent for the coating agent, and it is difficult to make the coating atmosphere sufficiently clean, so that surface defects of processed products due to adhesion of dust frequently occur. Problems such as deteriorating the environment due to organic solvents and impairing safety and hygiene arise.

[0008] If a water-based coating agent is used to form the primer layer and the primer layer is provided during the polyester film forming process, the primer layer is formed in a clean environment, so that dust adheres to the film surface. There is no risk of explosion or environmental degradation, which is advantageous in terms of economy and safety.

In order to take advantage of the above-mentioned advantages of using a water-based coating agent, for example, Japanese Patent Application Laid-Open No. Sho 54-43017 and Japanese Patent Publication No. Sho 4
JP-A-9-10243, JP-A-52-19786 and JP-A-52-19787 propose a technique using a water-soluble or water-dispersible polyester resin or acrylic resin as a primer. . However, when the above-mentioned water-soluble or water-dispersible polyester resin is used, there is a disadvantage that the adhesiveness to a film is poor, and when the above-mentioned water-soluble or water-dispersible acrylic resin is used, There is a defect that the adhesiveness to a film, the mechanical strength, and the adhesiveness to a magnetic layer are poor.

[0010]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a plastic film such as a polyester film having excellent light transmittance and excellent adhesiveness.

[0011]

The object of the present invention is to provide: (1) a plastic film provided with at least one layer formed from a coating solution containing at least two kinds of acrylic polymer latexes, Of the glass transition temperature (Tg _L ) of the acrylic polymer latex exhibiting the lowest glass transition temperature and the glass transition temperature (Tg _H ) of the acrylic polymer latex exhibiting the highest glass transition temperature among the various acrylic polymer latexes. A plastic film having a difference of 10 to 80C. (2) A plastic film provided with at least one layer formed from a coating solution containing at least two types of acrylic polymer latex, and having the lowest glass transition temperature among the at least two types of acrylic polymer latex. The difference between the glass transition temperature (Tg _L ) of the acrylic polymer latex and the glass transition temperature (Tg _H ) of the acrylic polymer latex exhibiting the highest glass transition temperature is 10 to 80 ° C. and the lowest glass transition temperature A plastic film, wherein each of the acrylic polymer latex exhibiting the above and the acrylic polymer latex exhibiting the highest glass transition temperature is a hydrophobic latex. (3) A plastic film provided with at least one layer formed from a coating solution containing at least two kinds of acrylic polymer latex, and showing the lowest glass transition temperature among the at least two kinds of acrylic polymer latex. The difference between the glass transition temperature (Tg _L ) of the acrylic polymer latex and the glass transition temperature (Tg _H ) of the acrylic polymer latex exhibiting the highest glass transition temperature is 10 to 80 ° C. and the lowest glass transition temperature A plastic film, wherein the acrylic polymer latex exhibiting the following is a hydrophilic latex, and the acrylic polymer latex exhibiting the highest glass transition temperature is a hydrophobic latex. (4) A plastic film provided with at least one layer formed from a coating solution containing at least two acrylic polymer latexes, and having the lowest glass transition temperature among the at least two acrylic polymer latexes. The difference between the glass transition temperature (Tg _L ) of the acrylic polymer latex and the glass transition temperature (Tg _H ) of the acrylic polymer latex exhibiting the highest glass transition temperature is 10 to 80 ° C. In the coating solution containing, the solid content of the acrylic polymer latex showing the lowest glass transition temperature is the solid content of the acrylic polymer latex showing the lowest glass transition temperature and the solid content of the acrylic polymer latex showing the highest glass transition temperature 5 to 95% by weight of the total amount of Plastic film to be. (5) The above (1) to (1), wherein at least one acrylic polymer latex is formed of a copolymer containing 10 to 80% by weight of a styrene component.
The plastic film according to any one of (4). (6) The above (1) to (1), wherein a layer formed from a coating liquid containing at least two kinds of acrylic polymer latex is provided adjacent to the plastic film.
The plastic film according to any one of (5). Therefore, it can be achieved.

Hereinafter, the present invention will be described in detail.

In the present invention, the acrylic polymer latex is a latex having an acrylic monomer such as methacrylic acid, acrylic acid, an ester or salt thereof, acrylamide or methacrylamide as a polymer constituent.

The acrylic polymer latex used in the present invention can be produced by an emulsion polymerization method. For example, using water as a dispersion medium, 10 to 50% by weight of a monomer with respect to water, 0.05 to 5% by weight of a polymerization initiator with respect to the monomer, and 0.1 to 20% by weight of a dispersant, 30-1
It can be produced by polymerizing under stirring at 00 ° C, preferably 60 to 90 ° C for 3 to 8 hours. Conditions such as the amount of the monomer, the amount of the polymerization initiator, the reaction temperature, and the reaction time can be widely changed.

Examples of the polymerization initiator include water-soluble peroxides (eg, potassium persulfate, ammonium persulfate, etc.) and water-soluble azo compounds (eg, 2,2′-azobis (2-aminodipropane) hydrochloride, etc.). Alternatively, a redox-based polymerization initiator in which a reducing agent such as an Fe ²⁺ salt or sodium bisulfite is combined can be used.

As the dispersant, a water-soluble polymer is used, and an anionic surfactant, a nonionic surfactant,
Either a cationic surfactant or an amphoteric surfactant can be used.

When the acrylic polymer latex is a hydrophobic latex, the average particle size is 0.01 to 0.8 μm.
m is particularly preferred, but any one of 0.005 to 2.0 μm can be preferably used. Also,
When it is a hydrophilic latex, the average particle size is from 0.01 to
0.8 μm is particularly preferred, but 0.005 to 2.0 μm
Any of these can be preferably used.

Examples of the acrylic monomer forming the acrylic polymer latex include methacrylic acid, acrylic acid, esters or salts thereof, acrylamide, methacrylamide and the like.

The acrylic polymer latex of the present invention can be produced by using an acrylic monomer alone or by using another monomer (hereinafter, referred to as a comonomer) copolymerizable with the acrylic monomer and the acrylic monomer. .

As the acrylic monomer, for example,
Crylic acid; methacrylic acid; acrylic acid esters, for example
For example, alkyl acrylate (for example, methyl acrylate
G, ethyl acrylate, n-propyl acrylate,
Isopropyl acrylate, n-butyl acrylate,
Isobutyl acrylate, t-butyl acrylate, 2
-Ethylhexyl acrylate, cyclohexyl acrylate
Rate, phenyl acrylate, Nil Acrylic
G, phenylethyl acrylate, etc.), containing hydroxy
Alkyl acrylate (for example, 2-hydroxyethyl
Acrylate, 2-hydroxypropyl acrylate
Methacrylates, for example, alkyl methacrylate
Acrylate (eg, methyl methacrylate, ethyl methacrylate
Acrylate, n-propyl methacrylate, isopropyl
Methacrylate, n-butyl methacrylate, isobu
Tyl methacrylate, t-butyl methacrylate, 2-
Ethylhexyl methacrylate, cyclohexyl methac
Acrylate, phenyl methacrylate, Nilmethacrylate
Rate, phenylethyl methacrylate, etc.), hydroxy
Si-containing alkyl methacrylates (eg, 2-hydroxy
Siethyl methacrylate, 2-hydroxypropyl meth
Acrylate, etc.); acrylamide; substituted acrylamide
(For example, N-methylacrylamide, N-methylol
Acrylamide, N, N-dimethylolacrylamide
, N-methoxymethylacrylamide, etc.);
Substituted methacrylamides (eg, N-methyl
Methacrylamide, N-methylol methacrylamide,
N, N-dimethylol methacrylamide, N-methoxy
Methyl methacrylamide, etc.);
Acrylate (for example, N, N-diethylaminoethyl
Acrylate); amino-substituted alkyl methacrylate
(E.g., N, N-diethylaminomethacrylate);
Epoxy-containing acrylates (for example, glycidyl acrylate
Acrylate); methacrylate containing an epoxy group (for example,
Glycidyl methacrylate); Acrylic acid salt (eg.
Sodium, potassium, ammonium salts);
Salts of tacrylic acid (eg, sodium salt, potassium salt,
Ammonium salts). One of the above monomers
Alternatively, two or more kinds can be used in combination.

Examples of the comonomer include styrene and derivatives thereof; unsaturated dicarboxylic acids (eg, itaconic acid, maleic acid, fumaric acid); esters of unsaturated dicarboxylic acids (eg, methyl itaconate, dimethyl itaconate, maleic acid). Methyl, dimethyl maleate, methyl fumarate, dimethyl fumarate); salts of unsaturated dicarboxylic acids (eg, sodium salt, potassium salt, ammonium salt); monomers containing sulfonic acid groups or salts thereof (eg, styrene sulfonic acid) , Vinyl sulfonic acid and salts thereof (sodium salt, potassium salt, ammonium salt); acid anhydrides such as maleic anhydride and itaconic anhydride;
Vinyl isocyanate; allyl isocyanate; vinyl methyl ether; vinyl ethyl ether; vinyl acetate. One or more of the above-mentioned monomers can be used in combination.

In the present invention, the hydrophobic latex is defined as a solubility parameter (SP).
Value is less than 15, refers to hydrophilic latex,
SP value is 15 or more.

The solubility parameter (solubility paramet)
er) The dimension of SP is (cal / ml) ^1/2 . Details of the solubility parameter are described in "Chemistry of Paint Resin" (Hiroshi Kakiuchi, published February 15, 1972), pp. 239-246.

The hydrophobic latex can be obtained by using a monomer having no water-soluble group. The hydrophilic latex can be obtained using a monomer having a water-soluble group such as a sulfonic acid group.

In the present invention, the glass transition temperature (Tg)
Is "Polymer Handbook" by Brand Wrap and others
It was determined by the method described on pages III-139 to III-179 (1966, Wiley and Sun).

The Tg (copolymer) of the copolymer can also be determined by the following equation.

[0027] Tg (copolymer) (° K) = v in _{1 Tg 1 + v 2 Tg 2} + ...... + v n Tg n _{-type, v 1, v 2 ...... v} n represents the weight fraction of monomer in the copolymer _{, Tg 1, Tg 2 ...... Tg} n is the homopolymer derived from the respective monomers in the copolymer Tg (° K)
Represents

The accuracy of Tg calculated according to the above equation is ±
5 ° C.

Next, the plastic film of the present invention will be described.

As the plastic film of the present invention,
For example, a cellulose nitrate film, a cellulose triacetate (hereinafter abbreviated as TAC) film, a cellulose acetate butyrate film, a cellulose acetate propionate film, a polyethylene terephthalate (hereinafter abbreviated as PET) film, a polyethylene naphthalate (hereinafter abbreviated as PET) Abbreviated as PEN.) Film,
Modified polyester films and polycarbonate films (hereinafter abbreviated as PC) described in JP-A-6-51437 are mentioned. Further, a laminate of the above-described film, an α-olefin polymer (eg, polyethylene,
Paper or the like coated or laminated with polypropylene or ethylene-butene copolymer). Of these, T
AC films, PET films, polyethylene-coated paper, and the like are commercially available and easily available.

The plastic film of the present invention may be colored according to the purpose of use.

When the plastic film of the present invention is used as a support which particularly requires transparency, such as a photosensitive material for printing, the plastic film is uncolored and transparent. It is colored neutral gray when used as a support for color films, and blue when used as a support for X-ray photosensitive material films. The purpose of coloring in these is prevention of light piping, prevention of halation, facilitation of diagnosis, and the like. When the plastic film of the present invention is used as a photographic support, the thickness of the plastic film is usually 50 to 200 μm.

The layer formed from the coating liquid containing at least two kinds of the acrylic polymer latex of the present invention (hereinafter, referred to as the primer layer of the present invention) is a coating liquid containing at least two kinds of the acrylic polymer latex of the present invention ( Hereinafter, the coating solution of the present invention) can be formed by coating and drying using a generally well-known coating method.

Examples of the coating method that can be used include dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, and US Pat. No. 2,68
No. 1,294, an extrusion coating method using a hopper. Also, if necessary, U.S. Pat. Nos. 2,761,791, 3,508,947, and 2,941,898
No. 3,526,528, Yuji Harazaki, "Coating Engineering", p. 253 (published by Asakura Shoten in 1973), etc., may be used to simultaneously apply two or more layers. it can.

Prior to the application of the coating solution of the present invention, the plastic film can be subjected to a pretreatment.

Since the PET film has a regular structure in which the surface is hardly adhered, it is particularly preferable to perform a pretreatment to form the primer layer of the present invention.

In the pretreatment, a so-called etching solvent (for example, phenol, cresol, resorcin, chloral hydrate, chlorophenol, etc.) treatment for bonding the primer layer of the present invention by an anchoring effect, mechanical treatment, corona discharge treatment, flame There are surface activation treatments such as treatment, ultraviolet treatment, high frequency treatment, glow discharge treatment, active plasma treatment, laser treatment, mixed acid treatment, and ozone treatment.

When the primer layer of the present invention is provided on a PET film, it can be provided during, before or after the film formation of the PET film. The coating amount of the coating liquid of the present invention is 0.01 to 10 cc per 1 m ^{2 in} solid content volume,
In particular, it is preferably 0.1 to 3 cc.

Drying conditions are generally at 120 to 200 ° C. for 1 hour.
It is about 0 seconds to 10 minutes.

A surfactant, a swelling agent, a matting agent, a dye for crossover, an antihalation dye, a pigment, an antifoggant, a preservative, and the like may be added to the coating solution of the present invention, if necessary. When the plastic film is a PET film or a PEN film, swelling agents such as phenol, resorcin, cresol, and chlorophenol are used, and the amount added is 1 per liter of the coating liquid of the present invention.
10 to 10 g may be sufficient. As a matting agent, a particle size of 0.1 to 10
Pills of silica, polystyrene spheres, methyl methacrylate spheres and the like are preferred.

[0041]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 << Preparation of Treated Plastic Film Samples 1 to 40 >> A biaxially stretched 100 μm thick polyethylene terephthalate film was subjected to a corona discharge treatment, and then a coating solution having the following formulation was applied at 20 ° C. and a relative humidity of 55%. Was applied by an air knife method under the following conditions. However, the coating liquid was applied so that the film thickness after drying was 0.8 μm to form a first undercoat layer.

(Formulation of Coating Solution) 261 g of a mixture of polymer latex A (solid content 30%) and polymer latex B (solid content 30%) (A) / (B) = 40/60 by weight ratio A) 30.0 g Distilled water was added to make 1000 ml, and a coating solution was applied.

As the polymer latex A, the polymer latex A-1 prepared as described below was used, and as the polymer latex B, the polymer latex B-1 prepared as described below was used.

<Preparation of Polymer Latex A-1> 300 parts by weight of degassed distilled water was put into a reaction vessel equipped with a stirrer, a reflux condenser, a dropping funnel, and a nitrogen inlet tube, and nitrogen gas was introduced through a nitrogen inlet tube. Then, the reaction vessel was placed under a nitrogen gas atmosphere, and dissolved oxygen in water was excluded. After raising the temperature to 80 ° C., 50 parts by weight of an aqueous solution containing 5 parts by weight of sodium dodecylbenzenesulfonate was added from a dropping funnel.
Also, a monomer mixture having the following composition
To 1 part by weight, 50 parts by weight of an aqueous solution containing 3 parts by weight of ammonium persulfate was added dropwise from another funnel, and a polymerization reaction was carried out at 80 ° C. for 8 hours under nitrogen gas reflux to obtain a water-dispersible polymer.

Composition of monomer mixture St / GMA / BA (20/40/40 (weight ratio)) St: styrene GMA: glycidyl methacrylate BA: butyl acrylate

<Preparation of Polymer Latex B-1> A polymerization reaction was carried out in the same manner as in Polymer Latex A-1, except that a monomer mixture having the following composition was used as the monomer mixture, to obtain a water-dispersible polymer.

Composition of monomer mixture St / GMA / BA (60/40 / 0.5 (weight ratio))

After performing a corona discharge treatment on the first undercoat layer, a coating solution having the following formulation was applied by an air knife method at 35 ° C. and a relative humidity of 22%. However, the coating liquid was applied so that the film thickness after drying was 0.1 μm, and then heat-treated at 140 ° C. for 2 minutes to form a second undercoat layer, thereby preparing a processed plastic film sample 1.

<Formulation of Coating Solution> Gelatin 9.6 g Surfactant (A) 0.2 g Surfactant (B) 0.2 g Ammonia 0.015 g Gelatin hardener (A) 0.12 g Silica having an average particle diameter of 3 μm Particles 0.14 g Distilled water was added to make 1000 ml, and the coating solution was applied.

[0051]

Embedded image

Table 1 and Table 2 as polymer latex B
In the same manner as the treated plastic film sample 1 except that the use ratio of the polymer latex A and the polymer latex B was changed as shown in Tables 1 and 2, the treated plastic film samples 2 to 4 were used.
0 was created.

The polymer latexes B-2 to B-6
Was obtained by performing a polymerization reaction in the same manner as in the polymer latex B-1 except that a monomer mixture having a composition shown in Table 2 was used.

Tables 1 and 2 show the glass transition temperature (Tg) of polymer latex A and polymer latex B and the difference in glass transition temperature (Tg) of polymer latex A and polymer latex B for each sample.

[0055]

[Table 1]

[0056]

[Table 2]

Obtained processed plastic film sample 1
For the samples No. to No. 40, the haze test was measured as follows.
Tables 3 and 4 show the obtained results. <Haze test> Turbidity meter Model- manufactured by Tokyo Denshoku Co., Ltd.
The transmittance (%) was measured using t-2600DA.

<< Preparation of silver halide photographic light-sensitive material >> On the second undercoat layer of the processed plastic film samples 1 to 40, a coating solution of a silver halide emulsion layer of the following formula 1 having a silver content of 2.9 g / m ² and the amount of gelatin was 1.2 g / m ^2, and a protective layer coating solution of the following formula 2 was simultaneously coated thereon so that the amount of gelatin was 0.6 g / m ² . An emulsion layer and a protective layer were formed to prepare a silver halide photographic light-sensitive material.

<Formulation 1: Composition of silver halide emulsion layer coating solution> Silver halide emulsion Silver amount 2.9 g / m ² sensitizing dye (C-5) 0.6 mg / m ² hydrazine compound (H-7) 30 mg / m ² amino compound (C-6) 50 mg / m ² Surfactant (C-7) 100 mg / m ² Latex polymer (C-8) 1.0 g / m ² Hardener (C-9) 30 mg / m ² sodium-isoamyl-n-decylsulfosuccinate 0.7 mg / m ² 2-mercapto-6-hydroxypurine 10 mg / m ² EDTA 50 mg / m ² Gelatin 1.2 g / m ²

<Formulation 2: Composition of protective layer coating solution> Gelatin 0.6 g / m ² sodium-isoamyl-n-decylsulfosuccinate 12 mg / m ² Matting agent: monodisperse silica having an average particle size of 3.5 μm 25 mg / m ² Hardener (C-10) 30 mg / m ² Surfactant (C-11) 1 mg / m ² Colloidal silica (average particle size 0.05 μm) 20 mg / m ²

[0061]

Embedded image

The adhesiveness of the obtained silver halide photographic material to a silver halide emulsion layer was measured in the following manner. Tables 3 and 4 show the obtained results.

<Adhesion to Photosensitive Material> The silver halide photographic light-sensitive material was coated with a film in a dry state before development processing (with a raw film), and with a film in a wet state during development processing under the following development processing conditions ( The film attached (with a dry film) in the dry state after development processing under the later-described development processing conditions was evaluated by the following evaluation method.

(With raw film) The silver halide photographic material before development processing was conditioned at 23 ° C. and 80% relative humidity for 24 hours, and the surface of the silver halide emulsion layer side was shaved with a razor at 45 °. Scratch the polyester film at an angle to reach the polyester film, press the cellotape (Cellotape, a registered trademark of Nichiban Co., Ltd.), pull it off rapidly, visually observe the peeled area of the silver halide emulsion layer, The evaluation was performed by the following five-step method.

Evaluation Criteria 1; Adhesion is very weak and 100% or more of the area is completely peeled off 2; 50% or more and less than 100% of the area is peeled 3; 20% or more and less than 50% of the area is peeled 4: Adhesive strength is strong, and an area of 5% or more and less than 20% is peeled off. 5: Adhesive strength is very strong, and is not peeled off at all or peeled area is less than 5% even if peeled. It can be considered that the film is sufficiently strong.

(With a wet film) A sharp needle is applied to the surface of the silver halide emulsion layer side of the silver halide photographic light-sensitive material which has undergone development processing under the following development processing conditions and has undergone the development step-fixing step-water washing step. The surface of the silver halide emulsion layer is wet and the rubber halide gloves are rubbed vigorously for 10 seconds, and the silver halide emulsion layer is peeled off. The area was visually observed, and the presence of a wet film was evaluated by a five-step method. Evaluation criteria are the same as those with a biofilm.

(With a dry film) The silver halide photographic light-sensitive material which has been subjected to development processing under the following development processing conditions and has been dried is conditioned at 23 ° C. and a relative humidity of 80% for 24 hours. The surface of the silver emulsion layer was scratched with a razor to reach the polyester film at an angle of 45 °, and a cellophane tape (Nichiban Co., Ltd. cello tape, registered trademark) was pressed and rapidly peeled off, and the silver halide emulsion layer was peeled off. The area was visually observed, and the presence of the dried film was evaluated by a five-step method. Evaluation criteria are the same as those with a biofilm.

If the evaluation is 4 or more, it can be considered that the film is sufficiently strong for practical use.

<Development Processing Conditions> (Step) (Temperature) (Time) Development 38 ° C. for 12 seconds Fixing 35 ° C. for 10 seconds Washing 40 ° C. for 10 seconds Drying 50 ° C. for 12 seconds Total of 44 seconds

<Developer composition> Amount per liter of each used solution Diethyltriamine pentaacetic acid / 5 sodium salt 3 g Sodium sulfite 50 g Potassium carbonate 40 g Hydroquinone 21 g 4-Methyl-4-hydroxymethyl-1-phenyl-3-hydrazolidone ( Dimezone S) 0.9 g Potassium bromide 5 g Benzotriazole 0.2 g 5-methyl-benzotriazole 0.13 g Boric acid 8 g Diethylene glycol 40 g 2-mercapto-6-hydroxypurine 0.06 g Add water and potassium hydroxide to make 1 liter. , PH = 10.2.

<Composition of Fixing Solution> Amount per liter of working solution Ammonium thiosulfate (70% aqueous solution) 200 ml Sodium sulfite 22 g Boric acid 9.8 g Sodium acetate trihydrate 34 g Acetic acid (90% aqueous solution) 14.5 g Tartaric acid 0 g Aluminum sulfate (27% aqueous solution) 25 ml The pH of the working solution was 4.9.

[0072]

[Table 3]

[0073]

[Table 4]

From the results shown in Tables 3 and 4, it can be seen that the plastic film of the present invention has a good haze and an excellent adhesion to the silver halide emulsion layer.

<< Use as OHP Sheet >> The processed plastic film samples 1 to 40 were used as OHP sheets, and black paper was copied with a copying machine (KONICA U-BIX 4345AF).

(Evaluation with film)
After adjusting the humidity for 24 hours under the condition of a relative humidity of 80%, the surface was scratched with a razor to reach the polyester film at an angle of 45 °, and a cellotape (Cellotape, a registered trademark of Nichiban Co., Ltd.) was pressure-bonded and abruptly pressed. Peeled off, OHP
The area peeled off from the sheet was determined, and the following five steps were used to evaluate the presence of a film.

Evaluation Criteria 3. Adhesive strength is very weak and 100% or more of the area is completely peeled off 2. Area of 50% or more and less than 100% is peeled 3. Area of 20% or more and less than 50% is peeled 4. 4. The adhesive strength is strong, and the area of 5% or more and less than 20% peels off. The adhesive strength is very strong, and the peeling area is less than 5% and the film is not peeled at all. If the evaluation is 4 or more, it can be considered that the film is sufficiently strong for practical use.

Tables 5 and 6 show the obtained results.

[0079]

[Table 5]

[0080]

[Table 6]

The plastic film of the present invention is made of OHP
It was found that the sheet exhibited good adhesive strength.

[0082]

The plastic film of the present invention has excellent light transmittance and excellent adhesiveness.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G11B 5/633 G11B 5/633 5/704 5/704

Claims (6)

[Claims] 1. A plastic film provided with at least one layer formed from a coating solution containing at least two kinds of acrylic polymer latexes, wherein the glass transition temperature is the lowest of the at least two kinds of acrylic polymer latexes. And the glass transition temperature (Tg _L ) of the acrylic polymer latex exhibiting the highest glass transition temperature.
plastic film the difference between g _H) is characterized in that it is a 10 to 80 ° C.. 2. A plastic film provided with at least one layer formed from a coating solution containing at least two acrylic polymer latexes, wherein the glass transition temperature is the lowest of the at least two acrylic polymer latexes. And the glass transition temperature (Tg _L ) of the acrylic polymer latex exhibiting the highest glass transition temperature.
g _H ), and the acrylic polymer latex exhibiting the lowest glass transition temperature and the acrylic polymer latex exhibiting the highest glass transition temperature are each hydrophobic latex. And plastic film. 3. A plastic film provided with at least one layer formed from a coating solution containing at least two acrylic polymer latexes, wherein the glass transition temperature is the lowest of the at least two acrylic polymer latexes. And the glass transition temperature (Tg _L ) of the acrylic polymer latex exhibiting the highest glass transition temperature.
g _H ), the acrylic polymer latex exhibiting the lowest glass transition temperature is a hydrophilic latex, and the acrylic polymer latex exhibiting the highest glass transition temperature is hydrophobic. A plastic film characterized by being latex. 4. A plastic film provided with at least one layer formed from a coating solution containing at least two kinds of acrylic polymer latexes, wherein the glass transition temperature is the lowest of the at least two kinds of acrylic polymer latexes. And the glass transition temperature (Tg _L ) of the acrylic polymer latex exhibiting the highest glass transition temperature.
g _H ) is 10 to 80 ° C., and the solid content of the acrylic polymer latex showing the lowest glass transition temperature in the coating liquid containing the acrylic polymer latex is the acrylic showing the lowest glass transition temperature. 5 of the total amount of the solid content of the acrylic polymer latex and the solid content of the acrylic polymer latex exhibiting the highest glass transition temperature
A plastic film characterized by being about 95% by weight. 5. The method according to claim 1, wherein the at least one acrylic polymer latex is formed of a copolymer containing 10 to 80% by weight of a styrene component.
5. The plastic film according to any one of 4. 6. The plastic film according to claim 1, wherein a layer formed from a coating solution containing at least two acrylic polymer latexes is provided adjacent to the plastic film. .