Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J11/00—Recovery or working-up of waste materials
  • C08J11/04—Recovery or working-up of waste materials of polymers
  • C08J11/06—Recovery or working-up of waste materials of polymers without chemical reactions
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2301/00—Characterised by the use of cellulose, modified cellulose or cellulose derivatives
  • C08J2301/08—Cellulose derivatives
  • C08J2301/10—Esters of organic acids
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W30/00—Technologies for solid waste management
  • Y02W30/50—Reuse, recycling or recovery technologies
  • Y02W30/62—Plastics recycling; Rubber recycling

Definitions

• This invention has to do with the.recovery of filmscrap, having a cellulose derivativebase, in which the scrap is, treated at an elevated temperature with water containing a cation. active detergent.
• photographic film comprises a base of; a cellulose derivative, preferably a cellulose ester, such as cellulose nitrate, cellulose acetate or a mixed ester of cellulose, such as cellulose acetate propionate. or cellulose acetate butyrate, overcoated with a gelatin layer containing a silver halide.
• a gelatin layer containing a silver halide.
• the scrap In carrying out our invention, it is preferred to first comminute the scrap, such as by chopping, although in some cases, such as with wide rolls of scrap film, it might be desirable to run a continuous process, by passing the sheeting through the recovery bath.
• the comminuted film In the case of the comminuted film, it is stirred with one or more changes of a solution of. a cation active detergent in water at an elevated. temperature after which the recovered film, base is rinsed and dried.
• the resulting product forms a, smooth, clear solution incoating solvents, which is a satisfactory indication of the, completeness of removal of the overcoatings, such as the gelatin layers and the subbing layers. which are present.
• the subbing layers which are susceptible to removalfrom the film in accordance with our invention, are any of the usual types of layers which are used to cause the gelatin layer to adhere to the film base. If the subbing layer is so moisture resistant that it will not be efiected by the solution of a cation active detergent at elevated temperature, it is not suitable to bond withthe gelatin layer.
• the preferred temperature of operation is 180-210" F. This temperature permits the use of the greatest amount of heat under normal pressure conditions. If, however, elevated pressures are not objectionable, the temperature may be raised above the boiling temperature of the water, the maximum temperature permissible being governed by the temperature which the film will stand without decomposing or being effected detrimentally.
• 180 F. isv preferred, as the lower limit, as only a short time is necessary for treating the film scrap, nevertheless, lower temperatures, such as from 180 down to 120 F., might be employed if sufiicient time is given for the treatment.
• a time of five minutes for each treatment is sufficient for a temperature of 210 and for the preferred temperature of 180-210 5-20 minutes is satisfactory for each treatment, especially where a plurality of treatments is given as is usually the case.
• a. total treatment time of 24 hours is desirable to give a substantially complete removal of the foreign material. 7
• the cation active detergent may be present in the water from .01% up to 25% or more, the higher limit being set only by the proportion of detergent which can be incorporated. In other words, very low concentrations of the detergent have been found to be effective and yet high concentrations have also given satisfactory results. However, in order to assure reuse of the liquid and economy of operation, it is preferred that the detergent be present in a proportion of .05%2%. In reusing the liquid, especially in cases of extended reuse, the liquid should be fortified at intervals by the further addition of small amounts of detergent. As pointed out previously, it is desirable, especially in case of comminuted scrap, to employ stirring as this uniformly exposes the particles of scrap to the action of the liquid and thereby gives a better treatment than would be possible where stirring is not employed.
• one treatment is sufficient to recover the ester employed as the film base.
• one treatment substantially removes all the foreign materials, but to obtain an excellent recovered product it is desirable to use more than one treatment. Twotreatments give a fairly satisfactory product and three are ordinarily sufficient to give a product of high quality. Further treatments may be given if desired but are ordinarily unnecessary.
• subbing layers which might be present and which are removable by our process are gelatin layers, whether hardened or not, layers of polyvinyl acetate (common known as Gelva resin), nitrate subbing layers, layers of resins, such as glyptal resins or mixtures of materials such as cellulose nitrate-gelatin or gelatin-oxidized cellulose acetate sub.
• Gelva resin polyvinyl acetate
• resins such as glyptal resins or mixtures of materials such as cellulose nitrate-gelatin or gelatin-oxidized cellulose acetate sub.
• the subbing layer except in the case of gelatin, is exceedingly thin, not exceeding one tenthousandth of an inch.
• the cation active detergents which are suitable for use in our process, are those of a watersoluble variety which have been previously mentioned in the prior art.
• the watersoluble cation active detergents disclosed in U. S. Patent No. 2,125,031 of Polak et al., are admirably suited for the purposes of our invention.
• Some of the compounds of this type, which give a good product when used in accordance with our invention, are triethyllaurylammonium bromide, triethyllaurylammonium perchlorate, lauryl pyridinium p-toluene-sulfonate, and dimethylbenzylcetylammonium chloride.
• the salts of other acids giving water-soluble products, such as the sulfates, may be employed.
• An example of compounds, which are valuable in our process are the quaternary ammonium salts having the following formula:
• R3-NX in which R represents aliphatic or aralkyl radicals, R represents aliphatic radicals, having 8 or more carbon atoms, and X represents an acid radical, giving water-soluble salts with the quaternary ammonium base.
• Example I 30 parts of film scrap, having a base of a lower fatty acid ester of cellulose, were chopped up and then boiled for one hour with 600 parts of a 0.5% solution of dimethyl benzyl cetyl ammonium chloride in water withoccasional agitation. The mother liquor was removed and the treatments were repeated twice, making a total of three treatments. The scrap was rinsed by boiling 6-8 times for fifteen minutes, each time with 600 parts of distilled water, and dried. The product gave a smooth, clear, brilliant solution in coating solvents, indicating complete removal of foreign materials known to be present in the untreated film scrap.
• Example II 40 parts of chopped processed film was boiled for three periods of one hour each with 600 parts of a 0.25% solution of dimethyl benzyl cetyl ammonium chloride. The scrap was rinsed, as in Example I, and dried. A solution of it in coating solvents was smooth and clear.
• Example III 30 parts of chopped film scrap was given 3 one hour boils with 600 parts of a 0.05% solution of dimethyl benzyl cetyl ammonium chloride in distilled water, rinsed, as in Example I, and dried. The product formed a grain-free solution in coating solvents.
• Example IV 30 parts of chopped film scrap was boiled with three successive portions of 600 parts each of a 1% solution of triethyllaurylammonium perchlorate in distilled water. The product was rinsed, as in Example I, and dried. It formed a smooth solution in coating solvents.
• a purified water be employed, as we have found that certain impurities in some types of water used in the boiling operations either decrease or completely destroy the effectiveness of our treatment. Therefore, it is essential in our process that a purified water, such as distilled or softened water, be used, or that the solution have a pH sufficiently acid to neutralize the effect of the water.
• the cellulose esters, recovered by our process, may be dissolved up in suitable coating solvents and used to form sheeting, or coatings, or any other purpose for which the use of a clear solution of a cellulose ester is desirable.
• a method of renovating film scrap having a base of a water-insoluble cellulose compound which comprises treating the scrap with a plurality of 0.5% solutions of dimethyl benzyl cetyl ammonium chloride in water, at a temperature above 120 F. but below the decomposition temperature of the film base until a surface coating is removed therefrom.
• a method of renovating film scrap having a base of a water-insoluble cellulose compound which comprises treating the scrap with a plurality of 1% solutions of triethyllaurylammonium perchlorate at a temperature above 120 F. but below the decomposition temperature of the film base until a surface coating is removed therefrom.
• a method of removing a thin layer of nitrocellulose from a base of a water-insoluble lower fatty acid ester of cellulose to which the layer is attached which comprises treating the cellulose ester material with a bath substantially free of alkali essentially consisting of a water solution of a water-soluble cation active detergent in which a negative substituent is linked directely to nitrogen, the cation portion of the detergent containing an alkyl substituent having at least 8 carbon atoms, at a temperature above 120 F. but below the decomposition temperature of the fatty acid ester of cellulose until the thin nitrocellulose layer is removed therefrom.
• a method of removing a thin layer of nitrocellulose from a base of a water-insoluble lower fatty acid ester of cellulose to which the layer is attached which comprises treating the cellulose ester material with a bath substantially free of alkali essentially consisting of water containing 0.05 to 2% of a cation active detergent in which a negative substituent is linked directly to nitrogen, the cation portion of the detergent containing an alkyl substituent having at least 8 carbon atoms, at a temperature of 180-210 F. until the thin nitrocellulose layer is removed from the base material.
• a method of renovating film scrap having a base of a water-insoluble lower fatty acid ester of cellulose and a subbing layer of nitrocellulose thereon, which comprises treating the scrap With a bath substantially free of alkali essentially consisting of a water solution of a water-soluble cation active detergent in which the negative substituent is linked directly to nitrogen, the cation portion of the detergent containing an alkyl substituent having at least 8 carbon atoms, at a temperature above F. but below the decomposition temperature of the film base until the nitrate subbing layer is removed therefrom.
• a method of renovating film scrap having a base of a water-insoluble lower fatty acid ester of cellulose and a nitrocellulose subbing layer thereon which comprises treating the scrap with a plurality of water solutions of a cation active detergent in water, at a temperature above 120 F. but below the decomposition temperature of the film base until the nitrate subbing layer is removed therefrom, the cation active detergent employed having a negative substituent linked directly to nitrogen and the cation portion of the detergent containing an alkyl substituent of at least 8 carbon atoms.
• a method of renovating film scrap having a base of a water-insoluble mixed ester of cellulose the acyl of which consists of fatty acid groups of 2-4 carbon atoms to Which is attached a thin layer of nitrocellulose which comprises treating the scrap with an alkali-free bath essentially consisting of a water solution of a water-soluble cation active detergent in which the negative substituent is linked directly to nitrogen, the cation portion of the detergent containing an alkyl substituent having at least 8 carbon atoms, at a temperature above 120 F. but below the decomposi tion temperature of the film base until the nitrate subbing layer is removed therefrom.
• a method of renovating film scrap having a base of a water-insoluble lower fatty acid ester of cellulose and a thin layer of nitrocellulose thereon which comprises treating the scrap with a 0.5% solution of dimethyl benzyl cetyl ammonium chloride in water, at a temperature above 120 F. but below the decomposition temperature of the film base until the thin nitrate layer is removed therefrom.
• a method of renovating film scrap having a base of a water-insoluble lower fatty acid ester of cellulose and a thin layer of nitrocellulose thereon which comprises treating the scrap with a 1% solution of triethyllaurylammonium perchlorate, at a temperature above 120 F. but below the decomposition temperature of the film base until the thin nitrate layer is removed therefrom.

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• Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
• Silver Salt Photography Or Processing Solution Therefor (AREA)

Priority Applications (2)

Applications Claiming Priority (1)

Publications (1)

Family

ID=22991961

Family Applications (1)

Country Status (2)

Cited By (2)

• 0
  • FR FR956720D patent/FR956720A/fr not_active Expired
• 1939
  • 1939-03-10 US US26110139 patent/US2288799A/en not_active Expired - Lifetime

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