JP2005321537A - Method for recovering resin support - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for recovering a support from a photographic sensitive material with a film formed using a silver salt of an organic acid and a synthetic polymer binder in a state where the support is reused as a material of a support for a photographic sensitive material. <P>SOLUTION: In the method for recovering a resin support by which a resin support is recovered from a photographic sensitive material comprising the resin support and a film comprising at least a silver salt of an organic acid and a synthetic polymer binder, the photographic sensitive material is treated with an alkaline treating liquid containing an alcoholic solvent. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for recovering a resin support used for a photographic light-sensitive material, particularly a polyester resin support.

  Polyester resins such as polyethylene terephthalate and polyethylene naphthalate are used as a support for silver halide photographic light-sensitive materials, heat-developable photographic light-sensitive materials, ink-jet recording materials, magnetic recording materials and the like due to their excellent characteristics, and further, liquid crystal displays, organic As an optical film used for various display devices such as an EL display, it is widely used in the information recording industry.

  In recent years, the information recording industry has undergone remarkable development and the number of polyester resin materials used has been rapidly increasing. Along with this, the amount of waste products (for example, inspection scraps and defective products generated in the product inspection process) and used products generated in the manufacturing process are increasing.

  In fact, most of these polyester-based resin material wastes are handled by landfill or incineration without being effectively used. However, in landfill, there is no decay, and incineration generates dioxins depending on the incineration conditions. It is also a cause of increasing the global environmental load. In addition, there is a problem of polyester raw material loss, which is not preferable from the viewpoint of resource saving.

  In particular, these polyester resins are used as a support, and for photosensitive materials using synthetic polymer materials as binders for coating films, they cannot be recovered and used as a support, and have been used. Most of the products and production scraps were not effectively used, and inevitably, in order to suppress the generation of dioxins, they were handled by incineration at a high temperature. For this reason, with the high temperature incineration process, the damage of the incinerator is quick, and there is a problem that a maintenance cost is required.

  In order to solve these problems, a method for recovering a polyester resin support from a photographic material using a polyester resin as a support has been studied. For example, a printing plate-making film using a copolymer of vinylidene chloride, itaconic acid, acrylic acid or the like as an undercoat layer and polyethylene terephthalate (hereinafter abbreviated as PET) as a polyester resin as a support in an aqueous solution of an alkali metal salt. A method for recovering a support by heat treatment at 50 to 95 ° C. with a cationic surfactant is known (for example, see Patent Document 1).

  A polyester resin support having an undercoat layer (hereinafter also referred to simply as a support) and a silver halide photographic light-sensitive material using the support are crushed into chips, and a surfactant (nonionic surfactant, cationic surfactant) And an anionic surfactant) are used together, and a method of recovering the support by heating with stirring in an aqueous alkali solution containing sodium hydroxide or potassium hydroxide at a temperature of 70 to 100 ° C. is known ( For example, see Patent Document 2.)

  However, when the support is recovered from a photographic material in which a coating film using a synthetic polymer binder is formed on the support by the recovery method described in Patent Documents 1 and 2, the peeled coating film or alkaline processing liquid is used. The sludge generated by the process reattaches to the support, or the coating film is mixed with the recovered support due to the incomplete peeling of the coating film and a part of the coating film remaining. At present, the purity is insufficient for reuse as a raw material for the support, and it cannot be used.

Under these circumstances, development of a method for recovering a support from a photographic light-sensitive material in which a coating film is formed using organic acid silver or a synthetic polymer binder in a state where it can be reused as a raw material for a support for a photographic light-sensitive material. Was desired.
Japanese Patent Laid-Open No. 11-302580 JP-A-8-146560

  The present invention has been made in view of the above circumstances, and its object is to provide a support for a photographic photosensitive material from a photographic photosensitive material in which a coating film is formed using an organic acid silver or a synthetic polymer binder. It is to provide a method for recovering a support in a state where it can be reused as a raw material.

  The above problem could be solved by the following configuration.

(Claim 1)
In a resin support recovery method for recovering a support from a photographic photosensitive material having a resin support and a coating film comprising at least an organic acid silver and a synthetic polymer binder, the support is recovered with an alkaline processing solution containing an alcohol solvent. A resin support recovery method characterized by the above.

(Claim 2)
The resin support recovery method according to claim 1, wherein the alcohol solvent has 3 or more carbon atoms.

(Claim 3)
The resin support recovery method according to claim 1 or 2, wherein the resin support is a polyester resin support.

(Claim 4)
The resin support recovery method according to any one of claims 1 to 3, wherein the alcohol solvent is 2 to 70% by mass of the treatment liquid.

  In a method for recovering a support from a used photographic light-sensitive material having a coating film composed of an organic acid silver and a synthetic polymer binder, the photographic light-sensitive material is treated with an alkaline processing solution containing an alcohol solvent. It has become possible to recover the support in a reusable state as a raw material for the material support.

  Hereinafter, although the specific form of this invention is shown, the form of this invention is not limited to this.

  The present invention swells a coating film by treating a photosensitive material having a coating film comprising at least an organic acid silver and a synthetic polymer binder on a resin support with an alkaline processing liquid containing an alcohol solvent, The resin support is recovered by peeling from the support.

  In the case of a conventional silver halide photographic light-sensitive material using a natural polymer binder such as gelatin, the coating film is swollen and dissolved by simply heat-treating with an alkaline aqueous solution, and the coating film is peeled off from the support. However, it is difficult to remove the film only with an alkaline aqueous solution in the photosensitive material containing the organic acid silver using the synthetic polymer binder according to the present invention. As a result of investigation, it is possible to peel from the support in a swollen state without dissolving the coating film by using an alcoholic solvent mixed with an alkaline aqueous solution. Has been found to be separable using the specific gravity difference. As a result, the quality can be improved to a level that can be used as a raw material for producing the photosensitive material support, and this problem can be easily solved.

  FIG. 1 is a flowchart for collecting a support according to the prior art.

  In the figure, 1 is a film removal step, 2 is a first separation step, 3 is a second separation step, 4 is an acid treatment step, and 5 is a water washing / drying step.

  In recovering a support from a conventional photographic light-sensitive material, an alkaline aqueous solution has been used in one film removal step. The coating film was peeled off in the alkaline aqueous solution 103 by placing the alkaline aqueous solution 103 and the chip-shaped photographic photosensitive material 102 in the film removal pot 101, adding a surfactant as necessary, and performing heat treatment. It includes a support, a peeled coating film, a support with a part of the coating film remaining, sludge generated by the treatment with the alkaline processing liquid, and a support on which the peeled coating film is reattached.

  Therefore, the first separation step 2, the second separation step 3, and the acid treatment step 4 are further performed, followed by a water washing / drying step 5 to obtain a recovery support at a level that can be used as a raw material for producing a support for photosensitive material. I was getting.

  Hereinafter, each process of 2-5 is demonstrated easily.

  The first separation step 2 is a step of separating solids from the alkaline treatment liquid in the film removal step.

  The first separation step 2 includes a hydrocyclone 201, a first collision type centrifugal dehydrator 202, and a draining means 203. There is no limitation in particular as the draining means 203, For example, an air cyclone, a screen conveyor, etc. are mentioned.

  Reference numeral 201a denotes a hopper that receives solids separated from the alkaline processing liquid by the hydrocyclone 201.

  From the upper discharge port 201d of the hydrocyclone, the alkaline processing liquid containing a part of the coating film peeled off and the generated sludge or the like is discharged.

  In order to separate and remove the coating film, sludge, and the like that have reattached to the support, it is introduced from the lower portion of the first collision type centrifugal dehydrator 202 from the hopper 201a.

  While the solution introduced into the first collision type centrifugal dehydrator 202 moves to the upper part while colliding with each other, a part of the deposit and the peeled coating film, sludge and the like are discharged from the lower part 202a. Solid matter is discharged from the upper portion 202b.

  The solid matter discharged from the upper part 202b of the first collision type centrifugal dehydrator 202 is introduced into the air cyclone 203, which is a draining means, and the adhering water is removed.

  The second separation step 3 includes a high shear stirring device 301 and a second collision type centrifugal dehydrator 302.

  In the second separation step 3, the peeled coating film and sludge are peeled off from the solids collected in the first separation step 2 by physical force, and the peeled coating film and sludge are subdivided and easily removed. And a step of separating the support.

  The solid matter is processed by applying a high shearing force with the high shear stirring device 301, so that the coating film or the ludge remaining on the support is peeled off, and at the same time, it is subdivided into a solution mixed with water. .

  In this state, the support is separated from the coating film, sludge, and the like by being introduced into the second collision type centrifugal dehydrator 302 and processed, and the support is recovered. When the support is recovered from the second collision type centrifugal dehydrator 302, it is recovered via an air cyclone as shown in the first separation step 2.

  Usually, since a slight coating film, sludge, and the like adhere to the support recovered at this stage, it is not yet in a state where it can be reused as a support for a photographic photosensitive material.

  In the acid treatment step 4, the support recovered from the second separation step 3 can be reused as a raw material for the support of the photographic material. The acid treatment apparatus 401 treats the support body while stirring the support body 402 collected from the second collision-type centrifugal dehydrator 302 with the acidic treatment liquid 403 using the stirrer 401b. By treating with an acidic treatment liquid, a slight coating film, sludge, and a fine coating film binder adhering to the support 402 are decomposed.

  The support recovered at the stage where the acid treatment is completed has no adhesion of foreign matters, and becomes the same level as the support used in the production of the photographic photosensitive material by separating the acidic processing solution. It can be reused.

  5 shows a water washing and drying process. The water washing / drying step 5 is a step in which the support treated in the acid treatment step 4 is washed with water and dried to make it reusable as a raw material for the support for a photographic photosensitive material.

  Reference numeral 501 denotes a water washing apparatus, and 502 denotes a drying apparatus. As the washing apparatus 501, a recovered support is efficiently washed. For example, a washing tank equipped with a stirrer or a mesh drum type container that can be rotated while showering washing water is used. When the drying is completed by the drying apparatus, the recovery of the support that can be reused as the raw material for the support of the photographic photosensitive material is completed.

  FIG. 2 is a schematic perspective view of a vertical mixer preferably used as the film removal pot 101 in the film removal step 1. The vertical mixer 105 stirs the alkaline processing liquid in the vertical tank 105a and the cylindrical vertical tank 105a having an open port at the top for processing the crushed chip-shaped photographic material and the alkaline processing liquid. A stirring blade 105c attached to the rotary shaft 105b for spraying, and a spraying device 105e for spraying the processing liquid on the inside of the vertical tank 105a. The spraying device 105e circulates the annular spray tube 105e1 that sprays the processing liquid on the inside of the vertical tank 105a, and the processing liquid in the vertical tank 105a, and supplies the processing liquid to the spraying pipe 105e1 through the supply pipe 105e3. And a circulation pump 105e2. The spray pipe 105e1d is disposed inside the vertical tank 105a via an attachment member 105f. Note that the processing liquid sprayed from the spray pipe 105e1 may be of a type that is sent by a pump from a separately prepared tank.

  The spraying is performed intermittently or continuously, and the spraying is a means for cleaning the solid matter sticking above the gas-liquid interface inside the vertical tank 105a.

  The stirring blade 105c is not particularly limited as long as it can apply a high shearing force to the crushed photographic photosensitive material chip, and examples thereof include a propeller, a flat blade, a flat blade disk turbine, and the like. A disk type is shown.

  3 is a schematic view of the first or second collision type centrifugal dehydrator (202, 302) of FIG. 1, FIG. 3 (a) is a schematic sectional view thereof, and FIG. 3 (b) is a collision type centrifugal separator. It is a schematic plan view of a dehydrator.

  In the figure, 302a indicates a cylindrical outer cylinder of a collision type centrifugal dehydrator, and 302b indicates a rotating rotor disposed inside the outer cylinder 302a. 302c shows a cylindrical separation cylinder. Reference numeral 302d denotes a motor for driving the rotary rotor 302b. Reference numeral 302c1 denotes a hole provided in the cylindrical separation cylinder 302c. Reference numeral 302b1 denotes a stirring blade attached to the surface of the rotating rotor 302b. When the rotary rotor 302b rotates (in the direction of the arrow in the figure), the processing blade is fed from the supply port 304 into the gap 303 between the separation cylinder 302c and the outside of the rotary rotor 302b. As the rotating rotor 302b rotates, centrifugal force acts, and the coating film, sludge, and treatment liquid peeled off from the support pass through and are removed from the holes provided in the separation cylinder 302c, and the support does not pass through the upper part. It is discharged and separated from the discharge port 305. The processing liquid that has passed through the hole is discharged from a discharge port 306 at the bottom of the outer cylinder 302a.

  FIG. 4 is a schematic view of a high shear stirring device used in the second separation step 3. 4A is a schematic cross-sectional view of the high shear stirring device, FIG. 4B is a schematic perspective view of a lower blade of the high shear stirring device, and FIG. 4C is an upper blade of the high shear stirring device. FIG.

  In order to recover only the support from the solid matter recovered in the first separation step 2, a high shear force is applied, and the coating film and sludge remaining on the support are peeled off and subdivided to form the support. A Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) is preferably used as an optimum device that facilitates separation and applies a high shearing force uniformly.

  In the figure, 301a represents a bottomed cylindrical body of the Henschel mixer, and 301b represents a lid. Reference numeral 301 c denotes a rotating shaft, 301 d denotes a lower blade attached to the rotating shaft 301, and 301 e denotes an upper blade attached to the rotating shaft 301.

  Conventionally, the support was recovered from the photographic light-sensitive material through each of the steps as described above, but in the present invention, a coating film comprising a resin support, at least an organic acid silver, and a synthetic polymer binder is used. As a method for recovering the support from the photographic light-sensitive material, the chip-shaped photographic light-sensitive material that has been crushed in the film removal step 1 is treated with an alkaline processing solution containing an alcohol solvent without dissolving the coating film. It has been found that it can be peeled off from the support, and after the film removal step, it is possible to use the steps 2 to 5 in FIG. 1 in the same manner, but many of them can be omitted. For example, the second separation step 3 and the acid treatment step 4 can be omitted.

  The resin support of the photosensitive material according to the present invention is not particularly limited. For example, JP-A-2000-206646, 2001-290243, 2002-99063, 2002-116320, 2002-132187, 2002-250990, The thing of 2003-1774 grade | etc., Is mentioned. The resin support is preferably a polyester support, particularly preferably polyethylene terephthalate (PET) or polyethylene naphthalate (PEN).

  Examples of the photographic photosensitive material using a resin support and a synthetic polymer binder and organic acid silver as a coating film according to the present invention include a heat-developable photosensitive material and a heat-sensitive recording material. In particular, JP-A-9-292671, JP-A-9-304870, JP-A-9-304871, JP-A-9-304882, JP-A-10-31282, JP-A-10-62898, JP-A-11-295844, and JP-A-11 It is preferably applied to the photothermographic material disclosed in Japanese Patent No. -352627.

  In the present invention, examples of the transparent or translucent synthetic polymer binder used for the coating film formed on the support include the following. For example: polyvinyl alcohol, hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, polyvinyl pyrrolidone, polyacrylic acid, polymethyl methacrylic acid, polyvinyl chloride, polymethacrylic acid, styrene-maleic anhydride copolymer, styrene-acrylonitrile copolymer Polymers, styrene-butadiene copolymers, polyvinyl acetals (eg, polyvinyl formal and polyvinyl butyral), polyesters, polyurethanes, phenoxy resins, polyvinylidene chloride, polyepoxides, polycarbonates, polyvinyl acetate, cellulose esters, polyamides , Polyvinyl butyral resin, cellulose acetate resin, cellulose acetate butyrate resin, polyester resin, polycarbonate Sulfonates resins, polyacrylic resins, polyurethane resins, vinyl chloride resin or the like.

  In the light-sensitive material according to the present invention, the organic acid silver is a reducible silver source for forming a black image, and a silver salt of an organic acid and a heteroorganic acid containing a reducible silver ion source, particularly a long chain ( The present invention can be preferably applied to a light-sensitive material containing an aliphatic carboxylic acid having 10 to 30, preferably 15 to 25 carbon atoms. Examples of organic acid silver are described in Research Disclosure Nos. 17029 and 29963. For example, silver gallate, silver oxalate, silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, capron Examples thereof include silver oxide, silver myristate, silver palmitate, silver maleate, silver fumarate, silver tartrate, silver linoleate, silver butyrate and silver camphorate. Particularly commonly used silver sources are silver behenate, silver arachidate and silver stearate.

  The alcohol solvent according to the present invention has one or more hydroxy groups, and may be monovalent or polyvalent, and may be a lower alcohol or a higher alcohol.

  A higher carbon number is preferable because it easily dissolves the organic acid silver in the film, but the effect is lost when it becomes insoluble in an aqueous solution. It is preferable to mix with at least alkaline warm water.

  Examples of monohydric alcohol solvents include (iso-, n-) propanol, (iso-, s-, t-, n-) butanol, (iso-, neo-, n-) pentanol, hexanol, heptanol, octanol. Nonylnol, decylnol, undecylnol, dodecylnol, methoxyethanol, methoxypropanol, methoxybutanol, methoxyethoxyethanol, ethoxyethanol, ethoxyethoxyethanol, ethoxypropanol, ethoxybutanol, butoxyethanol, butoxypropanol, butoxybutanol and the like are preferable.

  Examples of the polyhydric alcohol solvent include ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, glycerin, and polyoxyalkylene polyol. Two or more of these may be used in combination.

  The addition amount is 2% by mass to 70% by mass, more preferably 5% by mass to 50% by mass, and still more preferably 5% by mass to 20% by mass with respect to water.

  The alkali-treated water is preferably an NaOH solution or a KOH solution, and the addition amount is preferably 0.2 mol / l to 2 mol / l.

  This treated water is preferably at a high temperature, preferably 50 ° C to 100 ° C.

  The amount is 1 to 1000 times the mass of the resin support without particular limitation.

  Hereinafter, although an example is given and the concrete effect of the present invention is shown, the mode of the present invention is not limited to this.

Example 1
(Preparation of photographic material)
A half-cut size of SD-P manufactured by Konica Medical and Graphic Co., Ltd. was used as the photothermographic material. The support was a PET film and the thickness was 200 μm.

<Recovery of support>
The support was recovered by the support recovery process described in FIG.

(Peeling treatment with alkaline treatment liquid)
The prepared Konica Medical and Graphic Co., Ltd. SD-P half-cut size 1 kg was crushed to an average size of about 10 mm square with a smoke mill, and the sodium hydroxide solution and alcohol solvent were listed in Table 1. The treatment was performed under the conditions shown. The film was removed by stirring at a temperature of 90 ° C. for 1 hour.

  The support and the state of film removal at that time were observed. As shown in FIG. 1, the comparative product had to be separated by the hydrocyclone in the second separation step 3 and the centrifugal dehydrator in the acid treatment step 4 after the first separation step 2, but the alcohol of the present invention. By performing the first separation step 2 and then the water washing / drying step 5 by treating with an alkaline processing liquid containing a system solvent, a recovery support that can be sufficiently used as a raw material for the support is obtained. I was able to. The results are summarized in Table 1.

Example 2
(Peeling speed with treatment liquid)
The same film removal treatment as in Example 1 was performed. The time for film removal at that time was measured. The results are shown in Table 2.

  It can be seen that the method of the present invention has a very high film removal speed for a photographic light-sensitive material having a coating film comprising an organic acid silver and a synthetic polymer binder.

Example 3
(Used as separation liquid)
After peeling in the comparative example of Example 1, the support and the membrane removal mixture were collected from the peeling solution with a collection net, stirred at 30 ° C. for 10 minutes with the separation liquid shown in Table 3, and then allowed to stand. The separation state was confirmed. In the comparative alkaline solution alone, the peeled film and the support were mixed and reattachment was observed, but in the treatment liquid of the present invention, the support film settled without the release film reattaching to the support. The peeled coating film floated and was separated cleanly. The results are summarized in Table 3.

It is a flowchart of the support body collection | recovery by a prior art. It is a schematic perspective view of a vertical mixer. It is the schematic of a collision type centrifugal dehydrator. It is the schematic of a high shear stirring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Film removal process 2 1st separation process 3 2nd separation process 4 Acid treatment process 5 Dehydration / drying process 101 Defilming pot 201 Hydrocyclone 202 First collision type centrifugal dehydrator 301 High shear stirring apparatus 302 Second collision type centrifugal dehydration Machine 401 Acid treatment device 501 Flushing device 502 Drying device

Claims (4)

In a resin support recovery method for recovering a support from a photographic photosensitive material having a resin support and a coating film comprising at least an organic acid silver and a synthetic polymer binder, the support is recovered with an alkaline processing solution containing an alcohol solvent. A resin support recovery method characterized by the above. The resin support recovery method according to claim 1, wherein the alcohol solvent has 3 or more carbon atoms. The resin support recovery method according to claim 1 or 2, wherein the resin support is a polyester resin support. The resin support recovery method according to any one of claims 1 to 3, wherein the alcohol solvent is 2 to 70% by mass of the treatment liquid.

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