JP3287652B2 - Photographic support - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper substrate having a waterproof resin layer on one side of a paper substrate containing natural pulp as a main component (hereinafter may be abbreviated as "base paper"). The present invention relates to a resin-coated paper-type photographic support having a resin layer capable of forming a film on the side on which a constituent layer is provided, and has a good adhesion between a base paper and a resin layer capable of forming a film. The present invention relates to a resin-coated paper-type photographic support which is free from problems in the development processing such as contamination of the processing liquid and is suitable for environmental problems.

[0002]

2. Description of the Related Art As a photographic support, a resin-coated paper-type support in which a base paper surface is coated with a resin capable of forming a film is well known. For example, Japanese Patent Publication No. 55-12584 discloses a technique for a photographic support in which a base paper is coated with a film-forming resin, preferably a polyolefin resin. U.S. Pat. No. 3,501,298 discloses a technique for a photographic support in which both sides of a base paper are coated with a polyolefin resin. In addition, since the rapid photographic processing method for silver halide photosensitive materials was applied,
A photographic support in which both sides of a base paper are coated with a polyethylene resin is mainly put to practical use for photographic printing paper, and if necessary, a sharpness is provided in a resin layer on one image forming side. For application, it usually contains a titanium dioxide pigment.

However, the resin-coated paper-type photographic supports disclosed in these prior arts are completely or hardly decomposed by microorganisms even when buried in soil due to the resin. It was not biodegradable and had problems in terms of environmental protection.

On the other hand, as biodegradable plastics, polyethylene resin compositions mixed or blended with biodegradable starch and copolymers of ethylene and carbon monoxide are known. It was still insufficient in workability. Recently, aliphatic polyester-based resins have begun to attract attention in terms of biodegradability and moldability. As a polyester resin having excellent biodegradability and moldability, Plastics, Vol. 43, No. 10, p. 87
(1992). However, these polyester resins are good in terms of biodegradability, but still insufficient in terms of moldability.

[0005] First, a resin-coated paper-type photographic support is formed by extruding a molten resin composition from a slit die into a film on a normally running base paper using a melt extruder. It is produced in a series of steps of coating, pressing between a pressure roll and a cooling roll, and peeling off the roll after cooling. However, when a resin composition composed of a polyester-based biodegradable resin is used, moldability such as neck-in is poor compared to a conventionally known polyethylene-based resin composition, and thermal decomposition of the resin is difficult. It is necessary to extrude the resin composition at a relatively low temperature for reasons such as being likely to occur. Specifically, the melt extrusion temperature of the polyethylene resin composition is usually from 280 ° C to 340 ° C.
° C, but the melt extrusion temperature of the resin composition composed of the polyester-based biodegradable resin usually needs to be 250 ° C or lower, preferably 200 ° C or lower. The resin-coated paper-type photographic support in which the resin composition is extruded and coated at such a low temperature has a problem that the adhesiveness between the base paper and the resin layer becomes extremely insufficient.

A resin-coated paper type photographic support having insufficient adhesion between a base paper and a resin layer, and a photographic material having the support,
Not only does the resin layer tend to peel off from the base paper during its handling, making it completely non-commercially worthy, but also, especially when the resin layer peels off from the base paper at the edge of the support during the development processing. In some parts, the developing solution is absorbed by the base paper, causing a problem that the edge of the photographic material is stained and the edge of the support is stained.

Second, a polyester resin composition originally,
For example, when a photographic material is formed by coating a photographic component layer on a resin-coated paper-type photographic support material whose base paper is coated with a polyethylene terephthalate resin composition, the adhesion between the support and the photographic component layer, There was a tendency for the undercoating to be insufficient. When a polyester-based biodegradable resin composition is used as the polyester-based resin composition, the problem that the film of the photographic constituent layer is insufficient is not only reduced but rather worsened. In the middle, that is, in the wet state, the film formation of the photographic constituent layer with the support tended to be poor.
A photographic material having a poor photographic constituent layer with a film sometimes causes a serious problem in practical use due to peeling of the photographic constituent layer from the support during the development processing.

[0008]

SUMMARY OF THE INVENTION Accordingly, a first object of the present invention is to provide good adhesion between a base paper and a resin layer capable of forming a film, and therefore, a treatment liquid stain on the edge of the support. An object of the present invention is to provide a resin-coated paper-type photographic support which is free from problems in development processing and is adapted to environmental problems. The second object of the present invention is that the adhesiveness between the base paper and the resin layer capable of forming a film is good, and therefore, there is no occurrence of a problem in the development processing such as a processing liquid stain on the edge of the support, Another object of the present invention is to provide a resin-coated paper-type photographic support which has good film-forming properties between the photographic constituent layer and the support and is suitable for environmental problems. Other objects of the present invention will become clear from the description of the following specification.

[0009]

Means for Solving the Problems and Actions As a result of intensive studies to solve the above problems, the present inventors have provided a waterproof resin layer on one side of a paper substrate mainly composed of natural pulp, In a photographic support having a film-forming resin layer on the other side of the paper substrate on which the photographic component layer is provided, a polyester-based biodegradable resin layer is used as the film-forming resin layer, and the paper substrate and the polyester-based resin are used. It has been found that the object of the present invention can be achieved by providing an anchor coat layer or an adhesive layer between the resin layer and the decomposable resin layer.

It has been found that the object of the present invention is remarkably achieved by providing an undercoat layer on a polyester-forming decomposable resin layer. Further, the object of the present invention has been found to be remarkably achieved by using a resin layer containing a vinyl acetate-based copolymerized polyolefin resin or a polyester-based resin as a main component as an anchor coat layer or an adhesive layer. This is the invention.

The polyester biodegradable resin used in the practice of the present invention is not particularly limited as long as it is a biodegradable polyester resin, and various melting points, densities and melt flow rates (hereinafter referred to as JIS). The melt flow rate measured under the conditions of a test temperature of 190 ° C. and a test load of 2.16 kg in accordance with K 7210 may be abbreviated as MFR), a molecular weight, and a molecular weight distribution can be used. Melting point: 85-130 ° C, density: 1.0 g / cm ³
As described above, the MFR was 0.1 to 50 g / 10 min, and the number average molecular weight (M
n) is 30,000-60,000, and the weight average molecular weight (Mw) is 140,000-
Those having 300,000 and Mn / Mw of 4.5 or more can be advantageously used alone or in combination. Specific examples of the polyester-based biodegradable resin include NUC-Null biodegradable resin series sold by Nippon Unicar Co., Ltd.
The Pionore series of Showa Polymer Co., Ltd. can be mentioned.

As a method for providing the polyester biodegradable resin layer of the photographic support in the present invention on the base paper, an anchor coat layer for improving the adhesiveness of the polyester biodegradable resin layer to the base paper is provided. It is preferable to melt-extrude and coat the polyester-based biodegradable resin composition on the base paper using a melt extruder, but after manufacturing a polyester-based biodegradable resin film in advance, the film is anchor coated on the base paper with an anchor coat layer or Lamination or bonding may be performed via an adhesive layer.

[0013] The photographic support of the present invention is obtained by forming a resin composition containing a polyester-based biodegradable resin as a main component on a base paper having a running anchor coat layer by a melt extruder through a slit die thereof. It is preferable to manufacture by a so-called melt-extrusion coating method in which the material is cast and coated. At that time, the temperature of the molten film is preferably from 150 ° C to 250 ° C. As the slit die, a flat die such as a T-type die, an L-type die, or a fishtail type die is preferable, and the slit opening diameter is preferably 0.1 mm to 2 mm. Before coating the resin composition on the base paper, the base paper is preferably subjected to an activation treatment such as a corona discharge treatment or a flame treatment.
Further, as described in JP-B-61-42254, a resin layer may be coated on a running base paper after spraying an ozone-containing gas onto a molten resin composition in contact with the base paper.

The base paper preferably used in the practice of the present invention is provided with an anchor coat layer. The preferred anchor coat layer is selected from the viewpoint of adhesiveness between the polyester biodegradable resin layer and the base paper. And a resin layer containing a vinyl acetate-based copolymerized polyolefin resin or a polyester-based resin as a main component, and a resin layer containing a polyester-based resin as a main component is particularly preferable. Specific examples thereof include vinyl acetate-based copolymerized polyolefin resins, and vinyl acetate-based copolymerized polyolefin resin emulsions (trade names: V-100, V-20, manufactured by Mitsui Petrochemical Co., Ltd.).
0, V-300), and as the polyester resin for the anchor coat layer, Toyobo Co., Ltd.
Vironal MD series (for example, MD1100, MD1
330, MD1930, etc.).

As a method of providing an anchor coat layer on a base paper, a composition containing a vinyl acetate-based copolymerized polyolefin resin emulsion or an aqueous dispersion of a high-molecular polyester-based resin is subjected to size press or tab size press, blade coating, air knife, or the like. It is preferable to provide an anchor coat layer on the base paper by containing or applying it by coating such as coating. The content or coating amount of the vinyl acetate copolymerized polyolefin resin or the polyester resin for the anchor coat layer on the base paper is 0.1 g.
Although the range of at least / m ² is useful, the range of 0.2 to 15 g / m ² is preferred, and the range of 0.4 to 10 g / m ² is more preferred.
If the content or coating amount is too small, the adhesiveness between the polyester-based biodegradable resin layer and the base paper becomes insufficient, and if it is too large, the curl properties of the photographic support deteriorate, which is not preferable.

In the photographic support of the present invention, a film of a polyester-based biodegradable resin composition is prepared in advance, and the film is laminated or laminated on a base paper via an anchor coat layer or an adhesive layer. Can be manufactured. When producing the film, uniaxial stretching or biaxial stretching may be performed, and the stretching ratio can be arbitrarily selected. Examples of the anchor coating agent include an epoxy resin, an alkyd resin, an organic titanium ester compound, and an ethylene / acrylic acid copolymer in addition to the vinyl acetate-based copolymerized polyolefin resin and the polyester-based resin. Examples thereof include those mainly containing a system-based emulsion, a wax-based hot melt, and a polyurethane-based compound. Preferably, the base paper is subjected to corona discharge treatment to promote the adhesion of the anchor coat layer and the adhesive layer to the base paper.

In the present invention, the opposite side (hereinafter abbreviated as the front side) of the base paper of the photographic support opposite to the side on which the resin layer made of the polyester-based biodegradable resin composition is provided (hereinafter may be abbreviated as the front side). Is covered with a waterproof resin layer. As such a waterproof resin, a thermoplastic resin such as a polyolefin resin such as a polyethylene resin, a polycarbonate resin, a polyester resin, or a polyamide resin is preferable. Among them, a polyester biodegradable resin is particularly preferable from the gist of the present invention.
Further, it may be coated with an electron beam curing resin described or exemplified in JP-B-60-17104.

The coating thickness of the resin layer on the front side of the photographic support in the present invention is usefully in the range of 4 to 100 μm, preferably 6 to 50 μm, and more preferably 9 to 35 μm.
Is particularly preferred. The back surface of the base paper is coated with a waterproof resin layer, and the coating thickness is preferably set appropriately with the resin on the front side, particularly in a range where curl balance is obtained, and generally a range of 4 to 100 μm is useful. However, it is preferably in the range of 6 to 50 μm. Further, it is preferable that the front and back resin layers are coated sequentially, preferably continuously. The surface of the photographic support, on which the photographic component layer is coated, may be processed into a glossy surface, a slightly rough surface described in JP-B-62-19732, a matte surface or a silk surface. It is preferable that the surface of the back resin layer on the opposite side is usually processed to a matte surface.

Various additives can be contained in the front resin layer and, if necessary, in the back resin layer of the photographic support of the present invention. JP-B 60-3430, JP-B 6
No. 3-11655, Japanese Patent Publication No. 1-38291, Japanese Patent Publication No. 1-38292
Patent, JP-A-1-105245 and the like or titanium dioxide pigments or white pigments such as zinc oxide, talc, calcium carbonate, etc., fatty acid amides such as stearamide, arachidic amide, zinc stearate, calcium stearate , Aluminum stearate, magnesium stearate, zinc palmitate, zinc myristate,
Fatty acid metal salts such as calcium palmitate, JP-A-1-10
Hindered phenol, hindered amine, phosphorus-based, various antioxidants such as sulfur-based, described in 5245 publication, blue-based pigments and dyes such as cobalt blue, ultramarine, celian blue, phthalocyanine blue, cobalt violet, fast violet And magenta pigments and dyes such as manganese violet, and various additives such as a fluorescent whitening agent and an ultraviolet absorber described or exemplified in JP-A-2-254440 can be incorporated in an appropriate combination. These additives are preferably contained as a resin masterbatch or compound.

The object of the present invention can be more remarkably achieved by coating an undercoat layer on the surface resin layer on the side where the photographic constituent layer is provided. That is, due to the synergistic effect of the resin layer composed of the polyester-based biodegradable resin composition of the present invention and the subbing layer coated thereon, the film formation in the wet state between the photographic constituent layer and the support is remarkable. It was found to be improved.

The undercoat layer used in the practice of the present invention is preferably an undercoat layer containing gelatin as a main component. Examples of such gelatin include lime-processed gelatin, acid-processed gelatin, enzyme-processed gelatin, gelatin derivatives, such as gelatin reacted with an anhydride of dibasic acid, and low-molecular-weight gelatin described in JP-A-4-60633. Can be raised. In addition, other hydrophilic polymers such as polyvinyl alcohol and starch can be used in combination with gelatin. The amount of gelatin applied to the undercoat layer is as follows:
Range 0.005~1.0g / m ² are useful, preferably 0.01 to 0.3 g / m ^2, more preferably 0.015 to 0.1
g / m ² . Further, the pH of the undercoating liquid is not particularly limited, but is preferably pH 8 or less, more preferably pH 7 or less, from the viewpoint of storage stability.

In the undercoat layer used in the practice of the present invention,
Various additives can be included. As preservatives, p-hydroxybenzoic acid ester compounds described in or exemplified in JP-A-1-102551, benzisothiazolone compounds, isothiazolone compounds, etc., and as surfactants, alkylbenzene sulfonates, sulfonates and the like anionic compounds Surfactant, saponin,
Nonionic surfactants such as alkylene oxides, JP-B-47-9303, fluorinated surfactants described in U.S. Pat.No.3,589,906, etc., and sulfobetaine-type surfactants described in JP-A-1-66035 Activators, amphoteric surfactants such as amino acids, esters of amino alcohols, etc., as hardeners, active halogen compounds, vinyl sulfone compounds, aziridine compounds, epoxy compounds, acryloyl compounds, isocyanate compounds, chrome alum, chromium sulfate, etc. Other hardeners, toning agents, optical brighteners, matting agents,
A fog inhibitor, a stabilizer, a pH adjuster and the like can be appropriately combined and contained.

The method of providing the undercoat layer on the surface of the polyester-based biodegradable resin used in the practice of the present invention is as follows. On the resin surface on the side where the image forming layer is provided, apply an undercoat coating solution and dry to provide an undercoat layer,
It is preferable to use a so-called on-machine method. Alternatively, the resin-coated paper may be wound up, and if necessary, stored after winding up, and a new undercoat layer may be provided, that is, a so-called off-machine method. As an apparatus for applying the undercoat coating liquid,
Examples include air knife coaters, roll coaters, bar coaters, wire bar coaters, blade coaters, slide hopper coaters, curtain coaters, gravure coaters, flexographic gravure coaters, and combinations thereof. Prior to the application, it is desirable that the resin surface be subjected to an activation treatment such as a corona discharge treatment or a flame treatment. Various drying devices such as hot air dryers such as linear tunnel dryers, arch dryers, air loop dryers, sine curve air float dryers, etc., drying devices using infrared rays, heating dryers, microwaves, etc. Can be given.
Drying conditions are arbitrary, but generally, 60 to 150.
C. in seconds to 10 minutes.

The base paper used in the practice of the present invention includes:
Natural pulp paper containing natural pulp as a main component is preferable, but mixed paper made of synthetic pulp and synthetic fiber containing natural pulp as a main component may also be used.

The natural pulp constituting the base paper which is advantageously used in the practice of the present invention is disclosed in JP-A-58-37642, JP-A-60-67940, JP-A-60-69649, Kaisho 61
It is advantageous to use appropriately selected natural pulp as described or exemplified in -35442 and the like. Natural pulp is subjected to normal bleaching treatment of chlorine, hypochlorite, chlorine dioxide bleaching, alkali extraction or alkali treatment and, if necessary, oxidation bleaching treatment with hydrogen peroxide, oxygen, ozone, etc., and a combination treatment thereof. Wood pulp of treated softwood pulp, hardwood pulp, and softwood mixed pulp is advantageously used, and various types of kraft pulp, sulfite pulp, soda pulp and the like can be used.

The base paper used in the practice of the present invention may contain various additives during preparation of the stock slurry. As sizing agents, fatty acid metal salts or fatty acids, alkyl ketene dimer emulsions or epoxidized higher fatty acid amides, alkenyl or alkyl succinic anhydride emulsions described or exemplified in JP-B-62-7534, rosin derivatives, etc. As a paper strength enhancer, anionic, cationic or amphoteric polyacrylamide, polyvinyl alcohol, cationized starch, vegetable galactomannan, etc., as a wet strength agent, polyamine polyamide epichlorohydrin resin, etc., as a filler, clay, kaolin , Calcium carbonate, titanium oxide, etc., as a fixing agent, aluminum chloride, water-soluble aluminum salts such as bansulfate, etc., as a pH regulator, caustic soda, sodium carbonate, sulfuric acid, etc., other JP-A-63-204251, Color pigments described or exemplified in JP-A 1-266537, etc., colored dyeing It is advantageously allowed to contain appropriately combining a fluorescent brightening agent.

In the base paper used in the practice of the present invention, various water-soluble polymers, antistatic agents, and additives are added to the base paper before the anchor coat layer is applied by a preliminary size press or a tab size press. May be included.
Examples of water-soluble polymers include starch-based polymers, polyvinyl alcohol-based polymers, gelatin-based polymers, polyacrylamide-based polymers, and cellulose-based polymers described or exemplified in JP-A 1-266537, and sodium chloride and potassium chloride as antistatic agents. Alkaline metal salts such as calcium chloride, barium chloride, etc., colloidal metal oxides such as colloidal silica, organic antistatic agents such as polystyrene sulfonate, etc. Emulsion,
Ethylene-vinyl acetate copolymer, an emulsion of a copolymer containing at least ethylene and acrylic acid (or methacrylic acid) as described or exemplified in JP-A-55-4027 and JP-A-1-80538. Or latex, etc., as pigments, clay, kaolin, talc, barium sulfate, titanium oxide, etc., as pH regulators, hydrochloric acid, phosphoric acid, citric acid, caustic soda, etc., other than the above-mentioned coloring pigments, coloring dyes, fluorescent brighteners, etc. It is advantageous to incorporate the additives in an appropriate combination.

The anchor coat composition containing a vinyl acetate-based copolymerized polyolefin resin emulsion or a high-molecular polyester-based aqueous dispersion, which is preferably used in the practice of the present invention, may be used after or after a preliminary size press or tab size. Without being applied to the base paper. The anchor coat composition may contain various water-soluble polymers, antistatic agents, and additives used in a preliminary size press or tab size press as long as the effects of the present invention are not impaired. The thickness of the base paper used in the practice of the present invention is not particularly limited, but preferably has a basis weight of 20 to 250 g / m ² .

The base paper used in the practice of the present invention includes a thickness unevenness index Rpy in the papermaking direction defined below.
Is preferably 140 mV or less, more preferably 132 mV or less, and most preferably 125 mV or less. Here, the film thickness unevenness index Rpy is a value specifically determined as follows. A film manufactured by Anritsu Corporation for measuring a thickness variation of a sample as an electric signal via an electronic micrometer by moving a sample between two spherical styluses having a diameter of about 5 mm having a measurement pressure of about 30 g / stroke. Using a thickness measuring instrument, scan the sample in the papermaking direction at a constant speed of 1.5 m / min after adjusting the zero point under the condition that the sensitivity range of the electronic micrometer is ± 15 μm / ± 3 V to obtain the thickness of the sample in the papermaking direction. The fluctuation is measured and the measured signal value obtained is
Using an Ono Sokki Co., Ltd. FFT analyzer CF-300 type machine (input signal AC ± 1V , sampling 512 points), the time window is a Hanning window and the frequency range is 5
Fast Fourier transform is performed under the processing condition of 0 Hz, and a power spectrum (unit: mV) on a linear scale is obtained by adding and averaging 128 times of integration, and a square of each power value on a linear scale in a frequency range of 2 Hz to 25 Hz is obtained. It can be obtained by multiplying the value obtained by the summation by 2/3 and raising to the 1/2 power. Other processing conditions were CF-300.
Perform under the initial setting conditions of the model machine The film thickness unevenness index Rpy is 14
As a method of producing a base paper of 0 mV or less, specifically,
Hardwood pulp that is short fiber and easily smooth is used in an amount of 30% by weight or more, preferably 50% by weight or more, and beaten by a beater so that the long fiber content is reduced as much as possible. For example, the beaten pulp has a weight average fiber of the pulp after the beaten of 0.4 to 0.4.
It is preferable that the thickness is 0.75 mm. Then
Regarding stock slurry to which internal additives have been added,
No. 7642, JP-A-61-260240, JP-A-61-284762
Paper making method using a suitable paper making method as described or exemplified in Japanese Patent Application Publication No. JP-A-2006-210, etc. so that uniform formation can be obtained by a commonly used paper machine such as a fourdrinier paper machine and a round net paper machine. Thereafter, calendering is performed using a machine calender, a super calender, a heat calender, or the like, and a base paper having a film thickness unevenness index Rpy of 140 mV or less can be produced.

After applying an activation treatment such as a corona discharge treatment or a flame treatment to the backing resin layer surface of the photographic support in the present invention, various backcoat layers are coated for antistatic purposes and the like. Can be. The back coat layer includes JP-B-52-18020, JP-B-57-9059, and JP-B-57-9059.
No. 53940, JP-B-58-56859, JP-A-59-214849
JP, JP-A-58-184144 and the like or inorganic antistatic agents described or exemplified, an organic antistatic agent, a hydrophilic binder, a latex, a curing agent, a pigment, a surfactant and the like may be appropriately combined and contained. it can.

The photographic support in the present invention preferably has a film thickness unevenness index Rpy of 170 mV or less, more preferably 160 mV or less, more preferably 15 mV or less.
Those having 0 mV or less are more preferable.

The photographic support in the present invention is coated with various photographic constituent layers and is used for color photographic printing paper, for black-and-white photographic printing paper, for typesetting photographic paper, for copying photographic paper, for inverted photographic material, The silver salt diffusion transfer method can be used for various purposes such as negative and positive, and printing materials. For example, a silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiodobromide emulsion layer can be provided. Color coupler in silver halide photographic emulsion layer
To provide a multi-layer silver halide color photographic constituting layer. Further, a photographic component layer for a silver salt diffusion transfer method can be provided. As a binder for these photographic constituent layers, in addition to ordinary gelatin, hydrophilic polymer substances such as polyvinylpyrrolidone, polyvinyl alcohol, and sulfate compounds of polysaccharides can be used. Further, the above-mentioned photographic constituent layer can contain various additives. For example, as sensitizing dyes, cyanine dyes, merocyanine dyes, etc., as chemical sensitizers, water-soluble gold compounds, sulfur compounds, etc., as antifoggants or stabilizers, hydroxy-triazolopyrimidine compounds, mercapto-heterocyclic compounds, etc. , Hardening agents such as formalin, vinylsulfone compounds and aziridine compounds, coating aids such as alkylbenzenesulfonates and sulfosuccinate salts, etc., dialkylhydroquinone compounds etc. as antifouling agents, and other fluorescent brighteners, improving sharpness Dye, antistatic agent, pH adjuster,
A fogging agent and a water-soluble iridium compound, a water-soluble rhodium compound, and the like at the time of generation and dispersion of silver halide may be incorporated in an appropriate combination.

The photographic material according to the present invention is subjected to exposure, development, and stoppage according to the photographic material, as described in "Photosensitive Material and Handling Method" (Kyoritsu Shuppan, Goro Miyamoto, Photographic Technology Course 2). , Fixing, bleaching, and stabilization. Further, the multi-layer silver halide color photographic material may be treated with a developer containing a development accelerator such as benzyl alcohol, thallium salt, phenidone or the like, or may be treated with a developer substantially free of benzyl alcohol. it can.

[0034]

EXAMPLES The present invention will be described below in detail with reference to examples, but the contents of the present invention are not limited to the examples.

Example 1 A mixed pulp composed of 50% by weight of hardwood bleached kraft pulp, 35% by weight of hardwood bleached sulphite pulp and 15% by weight of softwood bleached sulphite pulp has a fiber length of 0.6 m.
m, and beaten to 100 parts by weight of pulp.
3 parts by weight of cationized starch, 0.2 parts by weight of anionized polyacrylamide, 0.4 parts by weight of alkyl ketene dimer emulsion (as ketene dimer), 0.4 parts by weight of polyamide epichlorohydrin resin and an appropriate amount of fluorescent brightener , A blue dye and a red dye were added to prepare a stock slurry. The fiber length of the pulp after beating was determined by JA
PAN TAPPI Paper Pulp Test Method No.52-89
Expressed as the length-weighted average fiber length measured with a Kajaani FS-100 type machine in accordance with "Paper and Pulp Fiber Length Test Method". Thereafter, the stock slurry was placed on a fourdrinier machine running at 200 m / min to form a web while giving appropriate turbulence, and the linear pressure was adjusted in the wet part in the range of 15 to 100 kg / cm. After performing a three-stage wet press,
Treat with smoothing rolls, and in drying part 3
After performing a two-stage tension press in which the linear pressure was adjusted in the range of 0 to 70 kg / cm, the resultant was dried. Thereafter, during the drying, the binder and the optical brightener of the kind and amount shown in Table 1 were used in an amount of 0.0.
5% by weight, 0.002% by weight of blue dye, 0.5% by weight of polystyrene sulfonate metal-based antistatic agent and the remaining weight%
Is pressurized to a size of 40 g / m ² , and the finally obtained base paper is dried so as to have a moisture content of 8% by weight with absolutely dry water, and machine calendered at a linear pressure of 70 kg / cm. The film thickness unevenness index Rpy with a basis weight of 170 g / m ² is 13
A photographic support base paper of 5 mV was prepared.

Next, after a corona discharge treatment is applied to the surface of the base paper (back surface) opposite to the side on which the photographic constituent layer is coated, a polyester biodegradable resin (trade name: Knucknal) sold by Nippon Unicar Co., Ltd. B prototype, density 1.14 g / cm ³ , MFR
= 4 g / 10 min) using a melt extruder and a resin temperature of 19
The resin was melt-extruded and coated at 0 ° C. with a resin thickness of 40 μm at a running speed of the base paper of 100 m / min. At this time, a cooling roll roughened by a liquid honing method was used as the cooling roll, and the operation was performed at a cooling water temperature of 12 ° C.

Subsequently, after the surface of the base paper was subjected to corona discharge treatment, the polyester-based biodegradable resin 67.
5 wt%, hydrated aluminum oxide titanium dioxide pigment consisting of (vs. Al ₂ O ₃ minutes as 0.5 wt% with respect to titanium dioxide) surface treated with 30 wt% titanium dioxide pigment and zinc stearate 2.5 wt% A resin composition comprising 35 parts by weight of a master batch and 65 parts by weight of the above-mentioned polyester-based biodegradable resin was melted at a resin temperature of 19 using a melt extruder.
The resin was melt-extruded and coated at 0 ° C. at a resin thickness of 32 μm at a running speed of the base paper of 100 m / min. At this time, a cooling roll having a mirror surface is used as the cooling roll, and the cooling water temperature 12
Operated at ° C. In addition, the melt extrusion coating of the front and back resin compositions was performed by a so-called tandem method in which extrusion coating was sequentially performed.

On the other hand, as a comparative example, instead of the polyester-based biodegradable resin, a polyester resin (trade name: Novatex HS004, density 1.33 g /
cm ³ , intrinsic viscosity [η] 0.7 dl / g ), except that melt extrusion coating was performed at a resin temperature of 290 ° C.

Further, after the corona discharge treatment on the back resin layer surface of the resin-coated paper, the following back coat coating solution was applied on-machine. As dry weight, colloidal silica: styrene
Acrylate copolymer latex = 1: 3, 0.021 g of polystyrene sodium sulfonate
/ m including other suitable amount of coating aid, etc. ² backcoat - DOO coating solution to obtain a photographic support by Coating with a latex content (in solid weight calculation) coating amount to be 0.42 g / m ² as .

Each sample obtained as described above was evaluated by the method described below.

As a method for evaluating the adhesiveness between the base paper of the photographic support and the resin layer, the sample was separated into a base paper layer and a surface resin layer containing a titanium dioxide pigment, and Tensilon manufactured by Orientec Co., Ltd. was used. Attached to a universal tester (CR-7000 type), the peeling strength (g / 15mm width) at 180 ° peeling at a pulling speed of 300m / min and a chuck of 50mm was measured. The adhesiveness between the resin and the resin layer was evaluated. The evaluation criteria were as follows: ○: good adhesion with peel strength of 250 g / 15 mm or more, Δ: 250 g / peel with peel strength of 100 g / 15 mm or more
Less than 15 mm, the adhesiveness is somewhat poor but there is no practical problem. X: The peel strength is less than 100 g / 15 mm, indicating poor adhesiveness and some practical problems.

As a method for evaluating the stain on the edge of the photographic support after the development processing, the photographic support was developed with each processing solution prepared by diluting a commercially available color developing solution kid with water. After drying at 70 ° C., the degree of dirt on the edge of the photographic support was visually evaluated.

The development processing conditions are as follows. Color development (35 ° C, 3 minutes 30 seconds) → bleach-fix (33 ° C,
1 minute 30 seconds) → stable (30 ° C, 3 minutes).

The evaluation criteria for stains after development of the edge of the photographic support were as follows: ○: good or no stain after development of the edge of the support, Δ: development of the edge of the support There is some dirt after processing, but there is no practical problem,
×: A lot of dirt on the edge of the support, causing some practical problems.
Represents

Table 1 shows the obtained results.

[0046]

[Table 1]

(Note 1) to (Note 6) in the table are as follows.

(Note 1) ○ indicates a sample according to the present invention.

(Table 2) Carboxy-modified PVA: carboxy-modified polyvinyl alcohol (trade name: Gosenal T-330H, manufactured by Nippon Synthetic Chemical Co., Ltd.).

(Note 3) Polyester resin: Aqueous dispersion of high molecular polyester resin, manufactured by Toyobo Co., Ltd., trade name Vironal MD-1930.

(Note 4) Vinyl acetate copolymer polyolefin resin: aqueous dispersion of vinyl acetate copolymer polyolefin resin manufactured by Mitsui Petrochemical Co., Ltd., trade name: Chemipearl V-300.

(Note 5) Polyester biodegradable resin: described in Example 1 of the specification.

(Note 6) Polyester resin: as described in Example 1 of the specification.

From the results in Table 1, it can be seen that the photographic support (paper-based) of the present invention, which is coated with a polyester-based biodegradable resin layer and has an anchor coat layer containing a polyester-based resin or a vinyl acetate-based polyolefin resin, is used. (Samples No. 3, No. 4, No. 7, No. 8 and No. 10)
It can be understood that is an excellent photographic support having good adhesion of the resin layer to the base paper, less contamination of the end portions of the support after the development processing, and biodegradability. The amount of the resin applied to the anchor coat layer is preferably 0.5 g / m ² or more in terms of dry weight from the viewpoint of the adhesion of the resin layer to the base paper (samples No. 3 and No. 4). Comparison).
On the other hand, the samples other than the present invention have poor adhesion of the resin layer to the base paper and have much stains after development of the end of the support (Sample N).
o.1 to No. 2) or non-biodegradable (samples No. 5, No. 6, and No. 9), and it is understood that there is a problem.

Example 2 Samples No. 4, No. 7, No. 8 and No. 1 of Example 1
0, after the backcoat coating solution was applied and before the resin-coated paper was wound up, the surface of the support containing the titanium dioxide pigment was subjected to a corona discharge treatment to give 1.5 g of lime-treated gelatin, 0.3 g of a 10% by weight methanol solution of butyl benzoate, sulfosuccinic acid-2-
5% by weight of methanol and water of ethylhexyl ester salt
It contains 0.45 g of the mixed solution and 0.36 g of a 10% by weight aqueous solution of the amphoteric surfactant represented by the formula (1), and the total amount is 100 parts with water.
g of the undercoating liquid having a formulation of 0.06 g.
g / m ² was uniformly applied on-machine to obtain a photographic support.

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Embedded image

Next, after performing a corona discharge treatment on the undercoat layer of the photographic support having the undercoat layer or on the photographic support having no undercoat layer or on the resin layer containing the titanium dioxide pigment. A black-and-white photographic printing paper was obtained by providing a photographic emulsion layer and its protective layer. The photographic emulsion layer is hexachloroiridium (II
I) Gelatin in the presence of 1.2 × 10 ⁻⁵ g of potassium acid 14.
ArBr / AgCl / AgI = 9 produced by producing and dispersing 19.2 g of silver halide grains with silver nitrate in 4 g.
Substantially [1, 0, 0] sensitized in combination with sulfur sensitization and gold sensitization to an optimum sensitivity of an average particle diameter of 0.6 μm having a halogen composition of 5 / 4.5 / 0.5 (mol%) Including a neutral silver halide photographic emulsion consisting of a surface, and in addition to gelatin necessary for film formation, appropriate amounts of stabilizers, sensitizing dyes, coating aids, hardeners, fluorescent brighteners, thickeners, include filter dyes, etc., 2.2 g / m ² silver nitrate were multilayer coating with a protective layer in a coating amount equivalent to 4.4 g / m ² gelatin. The protective layer contains a coating aid and a hardener in addition to gelatin corresponding to ² g / m ² .

The coated and dried sample was dried at 35 ° C. and under normal humidity.
After storage for one day, the sample was developed with a D-72 developing solution for 90 seconds, and the surface of the emulsion surface was scratched with a nail at intervals of 1 cm vertically and horizontally to make a grid-like scratch. Rubbing,
The degree of detachment of the photographic emulsion layer from the support was evaluated by the degree of peeling of the photographic emulsion layer. The peeling rate was represented by the area ratio (%) of the portion where the photographic emulsion layer was peeled off from the portion rubbed with the fingertip. The evaluation criteria were as follows: Grade 1: no peeling of the photographic emulsion layer at all, very good film attachment (peeling rate: 0%), Grade 2: Very little peeling of the photographic emulsion layer, but good filming (peeling rate) Grade 3: Little peeling of the photographic emulsion layer, but no practical problem with coating (peeling rate 0.5% or more and less than 2%), Grade 4: Peeling of the photographic emulsion layer Grade 5: Some extent of film coverage within practical limits (peeling rate 2% or more and less than 5%) Grade 5: Photographic emulsion layer peeled considerably, and film coating practically problematic (peeling rate 5% to less than 10%) ), Grade 6: Excessive peeling of the photographic emulsion layer and considerably poor film adhesion (peeling rate of 10% or more and less than 30%), Grade 7: Extremely large peeling of the photographic emulsion layer and extremely poor film adhesion (peeling) Rate of 30% or more).

As a result, Samples No. 4, No. 7, No.
The photographic supports provided with an undercoat layer in Nos. 8 and 10 had good adhesion of the resin layer to the base paper layer, and good grade 2 adhesion to the photographic emulsion layer with the support. And was particularly excellent. On the other hand, the photographic support having no undercoat layer was grade 5 with a film.

Example 3 The polyester biodegradable resin composition for the front and back sides used in Example 1 was melt-extruded at a resin temperature of 170 ° C. using a melt extruder, and was cooled at a cooling temperature of 12 ° C. or lower by a drum casting method. At a take-up speed of 40 m / min. The polyester biodegradable resin composition film containing the titanium dioxide pigment for the front was made 32 μm thick, and the polyester biodegradable resin film for the back was made 27 μm thick. Thereafter, a polyester biodegradable resin film for the front and back sides was laminated on the base paper used in Sample No. 1 of Example 1 to obtain a photographic support. At the time of bonding, an adhesive layer containing a urethane-based compound as a main component was previously applied to the film side, and the base paper and the film were bonded by pressing with a press roll.

The obtained photographic support was excellent in that the adhesiveness of the resin layer to the base paper was good and the end of the support was less contaminated after the development processing.

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According to the present invention, the adhesion between the base paper and the resin layer capable of forming a film is good, and therefore, there is no problem in developing processing such as stains of the processing liquid at the edge of the support. In addition, a resin-coated paper-type photographic support adapted to environmental problems can be provided. Further, according to the present invention, it is possible to provide a resin-coated paper-type photographic support having the above-mentioned properties and having good film formation between the photographic constituent layer and the support.

Claims (4)

(57) [Claims] 1. A photographic support having a waterproof resin layer on one side of a paper substrate mainly composed of natural pulp and a film-forming resin layer on the other side of the paper substrate on which a photographic component layer is provided. A photograph, wherein the resin layer capable of forming a film is a polyester biodegradable resin layer, and an anchor coat layer or an adhesive layer is provided between the paper substrate and the polyester biodegradable resin layer. Support. 2. The photographic support according to claim 1, wherein the polyester biodegradable resin layer contains a titanium dioxide pigment. 3. The photographic support according to claim 1, wherein an undercoat layer is provided on the polyester biodegradable resin layer. 4. The photographic support according to claim 1, wherein the anchor coat layer or the adhesive layer is mainly composed of a vinyl acetate copolymer polyolefin resin , a polyester resin and a urethane compound. .