JPH05200942A - Cellulose ester laminated film and production thereof - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the adhesion between the cellulose ester layer and the undercoat layer. Make the cellulose ester layer very easy to separate. [Structure] Reference numeral 10 is a cellulose ester layer, and a cellulose diacetate layer 20 is provided on the upper surface of the cellulose ester layer 10.
Are laminated, and further, this cellulose diacetate layer 20
A polycarbonate layer 30 is laminated on the upper surface of the. An undercoat layer 40 is laminated on the upper surface of the polycarbonate layer 30, and the undercoat layer 40 is formed of a copolymer composed of a diolefin monomer and a vinyl monomer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cellulose ester laminated film useful as a support for photographic light-sensitive materials and a method for producing the same, and more specifically, it has excellent adhesion of a cellulose ester layer to an undercoat layer, and The present invention relates to a recyclable cellulose ester laminated film and its manufacturing method.

[0002]

2. Description of the Related Art In a photographic light-sensitive material, a photographic emulsion is coated on the surface of a support, and in recent years, a support made of cellulose ester has been widely used. However, polyesters are hydrophobic, while photographic emulsions are hydrophilic. Therefore, if the photographic emulsion is directly coated on the surface of the cellulose ester support, the adhesion of the photographic emulsion layer to the support is significantly deteriorated. Therefore, the surface of the cellulose polyester support is coated with an undercoat liquid consisting of gelatin or a dissolved polymer in an organic solvent to form an undercoat layer to improve the adhesion to the photographic emulsion. However, the organic solvent used for such an undercoating liquid is generally poor in handleability, toxic to the human body, and highly likely to pollute the environment.

Therefore, an undercoating method has been proposed in which an aqueous dispersion is used in place of the organic solvent and the handling is good and there is no adverse effect on the human body and the environment (JP-A-55-65).
No. 949 publication).

[0004]

However, the undercoating method using the above-mentioned aqueous dispersion is preferable because the problems of the organic solvent are eliminated, but the adhesion between the undercoat layer and the cellulose ester support is preferable. There is a problem that it is inferior in sex.
Further, if a strong adhesion is imparted by introducing a chemical bond, it becomes difficult to separate the support from the photographic emulsion layer,
This causes problems when reusing cellulose ester film.

The present invention solves the above problems, has good adhesion between the cellulose ester layer and the undercoat layer, and can separate the cellulose ester layer from the photographic emulsion layer, etc., and contributes to resource saving and energy saving. An object of the present invention is to provide a cellulose ester laminated film which can be manufactured and a method for producing the same.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above object, and found that polycarbonate firmly adheres to an undercoat layer of an aqueous dispersion.
The present invention has been completed by finding that the cellulose ester layer can be easily separated by interposing the cellulose diacetate layer.

That is, the cellulose ester laminated film of the present invention comprises a cellulose ester layer and a cellulose diacetate layer laminated on the cellulose ester layer.
It is characterized by having a polycarbonate layer laminated on the cellulose diacetate layer, and an undercoat layer containing a copolymer composed of a diolefin monomer and a vinyl monomer laminated on the polycarbonate layer.

Further, the method for producing a cellulose ester laminated film of the present invention comprises casting a cellulose ester layer dope, a cellulose diacetate layer dope and a polycarbonate layer dope to form a cellulose ester layer, a cellulose diacetate layer and a polycarbonate layer. Is formed, and then the polycarbonate layer is coated with an aqueous dispersion of a copolymer containing at least a diolefin monomer and a vinyl monomer.

Examples of the cellulose ester of the cellulose ester layer include cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate. 62% cellulose acetate is preferred and 59-61% is particularly preferred.

The thickness of the cellulose ester layer is appropriately selected according to its use, but in the case of a photographic light-sensitive material, it is preferably in the range of 50 to 300 μm.

The cellulose ester layer is formed by casting a cellulose ester layer dope. The dope for the cellulose ester layer is mainly composed of the above-mentioned cellulose ester and organic solvent. Examples of the organic solvent include methylene chloride, chloroform, tetrachloroethylene, and dimethylacetamide. When cellulose acetate is used as the cellulose ester, the content of cellulose acetate in the dope is preferably 5 to 50% by weight, particularly preferably 8 to 27% by weight.

A plasticizer may be added to the cellulose ester layer in order to improve the flexibility or moisture resistance of the film. Examples of the plasticizer include triphenyl phosphate, biphenyl diphenyl phosphate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl glycolate and trimethyl trimellitic acid ester. The addition amount of the plasticizer is determined within a range that does not impair the flexibility of the membrane, and is preferably in the range of about 2 to 20% by weight, particularly preferably in the range of about 2 to 15% by weight, based on the cellulose ester.

As other additives, for the purpose of preventing edge lighting or optical filters,
Various dyes, ultraviolet ray or infrared ray absorbing agents and the like can be added alone or in combination. The addition amount is appropriately determined according to the purpose of use.

The cellulose diacetate layer is for separating the cellulose ester layer, and the cellulose diacetate preferably has an acetylation degree of 52 to 56%. Further, various additives similar to those of the cellulose ester layer can be added.

The thickness of the cellulose diacetate layer is 0.2
˜10 μm is preferable, and 0.5˜5 μm is particularly preferable.

The cellulose diacetate layer is formed by casting a cellulose diacetate layer dope. The dope for the cellulose diacetate layer is mainly composed of cellulose diacetate and an organic solvent. This organic solvent is the same as in the case of the dope for the cellulose ester layer. The content of cellulose diacetate in this dope is preferably 3 to 50% by weight, particularly preferably 5 to 25% by weight.

The polycarbonate layer is for improving the adhesion to the undercoat layer, and the polycarbonate is not particularly limited, but bisphenol A polycarbonate is a typical example.

Although the thickness of the polycarbonate layer is not particularly limited, it is preferably in the range of 0.2 to 10 μm.

The polycarbonate layer is formed by casting a polycarbonate layer dope. The polycarbonate layer dope is mainly composed of polycarbonate and an organic solvent. Examples of the organic solvent include methylene chloride and tetrachloroethylene. The content of polycarbonate in this dope is 10-
30% by weight is preferred and 15-23% by weight is particularly preferred.

The undercoat layer improves adhesion to photographic emulsions and the like, and contains a copolymer of a diolefin monomer and a vinyl monomer. This diolefin monomer means a monomer having two ethylene bonds in one molecule, and may be an aliphatic unsaturated hydrocarbon or a cyclic structure. For example, butadiene, which is a conjugated diene,
1,4-as isoprene, chloroprene, and non-conjugated dienes
Pentadiene, 1,4-hexadiene, 3-vinyl-1,5-hexadiene, 1,5-hexadiene, 3-methyl-1,5-hexadiene, 3,4-dimethyl-1,5-hexadiene, 1,2- Divinylcyclobutane, 1,6-heptadiene, 3,5-diethyl-1,5-
Heptadiene, 4-cyclohexyl-1,6-heptadiene, 3
-(4-Pentenyl) -1-cyclopentene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1,9-octadecadiene, 1-cis-9-cis-1,2-octa Decatriene, 1,10
-Undecadiene, 1,11-dodecadiene, 1,12-tridecadiene, 1,13-tetradecadiene, 1,14-pentadecadiene, 1,15-hexadecadiene, 1,17-octadecadiene,
There is 1,21-docosadiene.

Among these diolephin monomers, butadiene, isoprene and chloroprene, which are conjugated dienes, are preferable, and butadiene is particularly preferable.

Examples of vinyl monomers include (i) styrene, acrylonitrile, methyl methacrylate, vinyl chloride, vinyl acetate and derivatives thereof, (ii) acrylic acid, methacrylic acid, itaconic acid, alkyl esters of acrylic acid, acrylamide. , Methacrylamide, acrolein, methacrolein, glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, allyl acrylate, allyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide,
There are vinyl isocyanate and allyl isocyanate.

Examples of the above styrene derivatives include:
Methyl styrene, dimethyl styrene, ethyl styrene,
Diethylstyrene, isopropylstyrene, butylstyrene, hexylstyrene, cyclohexylstyrene, decylstyrene, benzylstyrene, chloromethylstyrene, trifluoromethylstyrene, ethoxymethylstyrene, acetoxymethylstyrene, methoxystyrene,
4-methoxy-3-methylstyrene, dimethoxystyrene,
Chlorostyrene, dichlorostyrene, trichlorostyrene, tetrachlorostyrene, pentachlorostyrene, bromostyrene, dibromostyrene, iodostyrene, fluorostyrene, trifluorostyrene, 2-bromo-4-
There are trifluoromethylstyrene, 4-fluoro-3-trifluoromethylstyrene, vinyl benzoic acid, and vinyl benzoic acid methyl ester.

The copolymer of the subbing layer is composed of diolefin monomer-vinyl monomer, and diolefin monomer-vinyl monomer of the above (i), or diolefin monomer-vinyl monomer of the above (i) -of the above (ii). Those composed of vinyl monomers are preferred. Particularly preferred copolymers are styrene-butadiene, styrene-isoprene, styrene-chloroprene, methylmethacrylate-butadiene, acrylonitrile-butadiene and the like.

The content of diolefin monomer in the copolymer is preferably 10 to 60% by weight, in particular 15 to 40% by weight, based on the total weight of the copolymer. The vinyl monomer is 90 to 40% by weight of the whole, but in particular, the above vinyl monomer
It is preferred that (i), especially styrenes, account for 70-40% by weight of the total copolymer.

The thickness of the undercoat layer is preferably 0.1 to 2.0 μm. The undercoat layer is laminated on the polycarbonate layer by applying an undercoat liquid. This undercoat liquid is mainly composed of the above-mentioned copolymer and water, and if necessary, a crosslinking agent, a surfactant, a swelling agent, a hydrophilic polymer, a matting agent, an antistatic agent and the like can be added. Further, the gel fraction of the copolymer of the undercoat liquid is preferably less than 80% by weight.

Here, the gel is a three-dimensionally copolymerized state, and its degree of three-dimensional polymerization is such that it does not substantially dissolve even when immersed in purified tetrahydrofuran at 20 ° C. for 48 hours. Say something. Therefore, the gel fraction means a value obtained by the following calculation formula.

[0028]

[Equation 1]

Here, W ₁ : weight of the copolymer in the sample taken W ₂ : a sample vacuum dried at 20 ° C. is kept in purified tetrahydrofuran at 20 ° C. for 48 hours, and this is filtered. The weight of solid content obtained by drying the thus obtained filtrate. That is,
W ₂ is the weight of the components eluted in tetrahydrofuran.

The cellulose ester laminated film of the present invention may be laminated with other films depending on its use. The film includes, for example, an antistatic layer, a sliding layer for improving the running property in the camera, a protective layer for preventing scratches, and an antihalation layer.

In order to produce the above-described cellulose ester laminated film, first, a three-layer laminated film consisting of a cellulose ester layer, a cellulose diacetate layer and a polycarbonate layer is formed, and then the polycarbonate layer of this laminated film is formed. The undercoat layer is laminated by coating. To form the three-layer laminated film, a co-casting die, a single-layer casting die, or a combination thereof may be used. That is, even if three layers are formed at once with a co-casting die, or if they are successively cast using separate casting dies (the dope cast earlier is completely solidified and then the dope is cast, so-called (Including the case of coating.) Two layers may be co-cast and one layer may be separately cast.

In the cellulose ester laminated film of the present invention, the cellulose ester layer can be separated by immersing it in a separating solvent. Examples of the separating solvent include ketones represented by acetone, methyl cellosolve acetate, and nitromethane.

The cellulose ester laminated film of the present invention can be used as a support for photographic light-sensitive materials, an optical film, a polarizing film and the like. When it is used as a support for a photographic light-sensitive material, a photographic emulsion is coated on the undercoat layer to produce a photographic light-sensitive material. As the photographic emulsion, any known emulsion can be used.

[0034]

In the present invention, the polycarbonate layer firmly adheres the undercoat layer, and the cellulose diacetate film layer is dissolved in the separating solvent to easily separate the cellulose ester film layer.

[0035]

EXAMPLE One example of the cellulose ester laminated film according to the present invention will be described with reference to FIG.

FIG. 1 is a partial sectional view of a cellulose ester laminated film. In FIG. 1, reference numeral 10 is a cellulose ester layer, a cellulose diacetate layer 20 is laminated on the upper surface of the cellulose ester layer 10, and a polycarbonate layer 30 is further laminated on the upper surface of the cellulose diacetate layer 20. An undercoat layer 40 is laminated on the upper surface of the polycarbonate layer 30, and the undercoat layer 40 is formed of a copolymer composed of a diolefin monomer and a vinyl monomer.

Next, a method for producing the above cellulose ester laminated film will be described with reference to FIG.

FIG. 2 is a sectional view of a co-casting die for carrying out the method for producing a cellulose ester laminated film of the present invention. In FIG. 2, reference numeral 50 denotes a co-casting die, and a casting support base 60 is provided below the co-casting die 50. The co-casting die 50 has a first manifold 51, A second manifold 52 and a third manifold 53 are formed.

Then, the first manifold 51 is provided with the cellulose ester layer dope 11, the second manifold 52 is provided with the cellulose diacetate layer dope 21, and the third manifold 53.
Are filled with a dope 31 for a polycarbonate layer, and these dopes 11, 21, and 31 are co-cast on a casting support 60. The cast dopes 11, 21, and 31 are solidified on the casting support 60 to form a three-layer laminated film including the cellulose ester layer 10, the cellulose diacetate layer 20, and the polycarbonate layer 30.

Next, the three-layer laminated film is sent to the undercoating step (not shown), and the undercoat liquid is applied to the polycarbonate layer 30 to form the undercoat layer 40.

Next, specific examples of the cellulose ester laminated film of the present invention and the method for producing the same will be described.

Example 1 A cellulose ester laminated film comprising a cellulose ester layer 10, a cellulose diacetate layer 20, a polycarbonate layer 30 and an undercoat layer 40 shown in FIG. The thickness of each layer is shown in Table 1.

Using the following dope, a co-casting die shown in FIG. 2 was used to form a laminated film consisting of a cellulose ester layer, a cellulose diacetate layer and a polycarbonate layer, and then the following undercoat liquid was applied to the polycarbonate layer. A subbing layer was formed. [Cellulose ester layer dope] -Cellulose triacetate (acetylation degree 59.5%) 22 parts by weight [Cellulose diacetate layer dope] -Cellulose diacetate (acetylation degree 55%) 18 parts by weight [Polycarbonate layer dope] -Polycarbonate (Weight average molecular weight 30,000) 19 parts by weight [Undercoat liquid] ・ Butadiene-styrene copolymer latex (solid content 50%, butadiene / styrene weight ratio = 40/60, gel fraction 38%) 10cc ・ 2,4-dichloro- 6-hydroxy-s-triazine sodium salt 8% aqueous solution 2cc-distilled water 150cc

Example 2 Example 1 is the same as Example 1 except that the undercoat liquid shown below is used. [Undercoating liquid] ・ Butadiene-styrene copolymer latex (solid content 50%, butadiene / styrene weight ratio = 40/60, gel fraction 95%) 10cc ・ 2,4-dichloro-6-hydroxy-s-triazine sodium salt 8 % Aqueous solution 2cc ・ distilled water 150cc

Comparative Example 1 A laminated film comprising a cellulose ester layer 10 and an undercoat layer 40 shown in FIG. The thickness of each layer is shown in Table 1.

The following dope was used to form a cellulose ester film with a single layer casting die, and then the following undercoat liquid was applied. [Cellulose Ester Layer Dope] The same as in Example 1. [Undercoating liquid] The same as in Example 1.

Comparative Example 2 A laminated film comprising a cellulose ester layer 10, a polycarbonate layer 30 and an undercoat layer 40 shown in FIG. The thickness of each layer is shown in Table 1.

The following dope was used and the manifold was 2
A co-casting die was used to form a laminated film composed of a cellulose ester layer and a polycarbonate layer, and then the following undercoat liquid was applied. [Cellulose Ester Layer Dope] The same as in Example 1. [Polycarbonate Layer Dope] Same as in Example 1. [Undercoating liquid] The same as in Example 1.

Adhesion Test of Undercoat Layer The undercoat layer of the cellulose ester laminated films produced in Examples 1 and 2 and Comparative Examples 1 and 2 were reticularly scratched at a distance of about 4 mm using a razor blade. , Adhere an adhesive tape (Scotch Permacell tape made by Sumitomo 3M) on it, and peel it off momentarily. And the peeled portion is 0-5
"A" when less than%, "B" when less than 5 to 30%,
The case of 30% or more was defined as "C". The results of Examples 1 and 2 and Comparative Examples 1 and 2 are shown in Table 1. In addition, Example 2 had a slightly lower adhesive strength when wet than Example 1.

Separation Test of Cellulose Ester Layer Each of the light-sensitive materials produced in Examples 1 and 2 and Comparative Examples 1 and 2 was cut into a piece of 1 cm square, and then cut into an acetone / methanol (weight ratio 7/3) mixture. Was immersed and stirred at room temperature in, and the separability of the cellulose ester layer was visually evaluated. The results are shown in Table 1.
Shown in.

[0051]

[Table 1]

From the results of the adhesion test of the undercoat layer, it was confirmed that Examples 1 and 2 having the polycarbonate layer had better adhesion than Comparative Example 1 having no polycarbonate layer.

From the results of the cellulose ester layer separation test, Example 1 having a cellulose diacetate layer was obtained.
It was confirmed that in Examples 2 and 2, the separability of the cellulose ester layer was better than in Comparative Examples 1 and 2 which did not have the cellulose diacetate layer.

[0054]

INDUSTRIAL APPLICABILITY In the present invention, the adhesion between the cellulose ester film layer and the undercoat layer is large, and as a result, the adhesion between the photographic emulsion and the like is large. Further, since the cellulose ester layer can be easily separated, the cellulose ester film can be recovered from the used laminated film and reused.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing a layer structure of an example of a cellulose ester laminated film according to the present invention.

FIG. 2 is a sectional view of a co-casting die for carrying out the method for producing a cellulose ester laminated film of the present invention.

FIG. 3 is a partial cross-sectional view showing a layer structure of a cellulose ester laminated film of a comparative example.

FIG. 4 is a partial cross-sectional view showing a layer structure of a cellulose ester laminated film of a comparative example.

[Explanation of symbols]

 10 ... Cellulose ester layer 11 ... Cellulose ester layer dope 20 ... Cellulose diacetate layer 21 ... Certose diacetate dope 30 ... Polycarbonate layer 31 ... Polycarbonate layer dope 40 ... Undercoat layer 50 ... Co-casting die

Claims (2)

[Claims] 1. A cellulose ester layer, and a cellulose diacetate layer laminated on the cellulose ester layer,
A cellulose ester laminated film comprising a polycarbonate layer laminated on the cellulose diacetate layer, and an undercoat layer containing a copolymer composed of a diolefin monomer and a vinyl monomer laminated on the polycarbonate layer. 2. A dope for a cellulose ester layer, a dope for a cellulose diacetate layer and a dope for a polycarbonate layer are cast to form a laminated film composed of a cellulose ester layer, a cellulose diacetate layer and a polycarbonate layer, and then the polycarbonate layer is formed. A method for producing a cellulose ester laminated film, which comprises applying an undercoat liquid containing a copolymer of at least a diolefin monomer and a vinyl monomer.