US 2807557 A
Description (OCR text may contain errors)
Fatenterl Sept. 24, 1957 METHOD OF TREATING FURS Clifford R. Carney, Seattle, Wash.
No Drawing. Application April 16, 1951, Serial No. 221,331
11 Claims. (Cl. 117-141 The present invention relates to a novel composition of matter which is particularly adapted for use in the treatment of furred animal pelts, and to a novel method which utilizes said novel composition in treating such pelts.
The processing of furred animal pelts requires the extensive use of water or other aqueous treating or cleaning solutions. This occurs not only in the initial soaking and tanning of the raw or dried pelts, but also occurs in the subsequent processing operations which may include stretching and shaping of the pelts and the bleaching or dyeing of the fur thereon. In all such processing, it is important to secure penetration of the pelt and the fur by the water or aqueous solution utilized. After such penetration, the water or other aqueous constituents which have penetrated both the fur and skin portions of the pelt must be removed, and the pelt dried. During such processing, the wet pelt is very soft and pliable, and is easily worked. Removal of the water or aqueous treating solution, and the subsequent drying of the pelt causes the pelt to lose much of its softness and pliability. The pelt, on drying, becomes less flexible, the appearance of the fur deteriorates, and the bond or union between the skin and the fur hairs is weakened frequently causing excessive shedding of the fur hairs.
Surface treatments heretofore have been used in an attempt to restore the appearance of the fur. Such treatments frequently utilize the application of wax, glazing or polishing solutions, or the like, to impart a gloss to the fur hairs and to reduce the amount of fur shedding. Such treatments, at best, are temporary expedients and do not restore or maintain the natural appearance of the fur or the bond between the fur and the skin of the pelt. Such treatments have little or no effect on preserving or improving the pliability of the dried pelt.
I have observed that the successive wetting and drying of fur pelts causes a progressive hardening of the skin portion of such pelts and progressive deterioration in the appearance of the fur portion. The fur becomes matted and loses its natural texture. I have observed, also, that the rate of shedding of the fur hairs is increased as the pelt loses its pliability. This is due primarily, I believe, to a shearing action which results from the hardening of the skin of the pelt.
While the exact reactions causing these changes are at present incompletely understood, it is believed that the wetting of a pelt and its subsequent drying reduces the motility of the connected fibers and fibrils which compose the inner layer or corium of the skin. There is reason to believe that this is probably due to the formation of a glue-type adhesive between the fibers and the fibrils, such as is known to be formed by the reactions which follow the wetting of the skin portion of the pelt with Water or aqueous solutions. The presence of relatively insoluble mucines in the skin portion of the pelt also contributes to the hardening of the pelts. Water or aqueous solutions are known to promote reactions with the water soluble skin portion of the pelt which form mucilaginous products which will act as a glue upon drying. The progressive hardening of the pelt skin due to successive treatments with Water or other aqueous treating solutions causes the oil glands of the individual hairs, immediately below the thin epidermis or outer layer of the skin, to become hardened. This hardened skin subsequently causes severance of the fur hair at points adjacent the rootsthereof.
The fur hairs and the skin both are provided with an outer dense, waterproofing layer, formed of highly insoluble keratin. The protective hair layer is called the cuticle; the protective skin layer is called the epidermis. The materials conventionally used in the above surface treating operations do not materially penetrate these protective layers. Instead, they merely add to the waterproofing already alforded by the cuticle and the epidermis In addition, since these materials frequently contain waxes which are polymerized readily in air, the period of their usefulness is limited and the treatments must be repeated at frequent intervals. A
The inherent color characteristics of the fur pelt are due to the pigments of the fur hairs which are located in the cortex layer. These pigments and the cortex layer are covered and protected by the insoluble cuticle layer. In live pelts, the color of these pigments is preserved by the natural oils which flow by well known physical mechanisms from the oil secreting reservoirs in the corium of the skin, through the central capillary passage of the hair, called the medulla. During the processing of the pelt, these natural oils of the 'skin are removed and the medulla is filled with insoluble keratin. Waxes, such as are conventionally used in the surface treatments above referred to, do not normally penetrate the skin to any appreciable extent and, even if they did, they could not be drawn through the medulla, due to their viscosity characteristics.
As distinguished from the methods used in prior practice, the present invention provides a method and composition for preserving the pliability of the skins through successive wetting and drying operations and for maintaining the fur hairs firmly bonded to the skins and at the same time improving the color, luster, general appearance and feel of the furs.
It is accordingly an object of the present invention to provide a novel composition of matter and a method for the use thereof in treating furred animal pelts to preserve the pelts for long periods of time, and to assure the maintenance of the skin portion of the pelt as .a permanently pliable element which securely and firmly holds the fur hairs in place. 7
Another object of the invention is to provide a novel composition of matter and a method for treating furred animal pelts by which the color, texture and appearance of the fur is improved over fur treated by conventional materials and methods, the individual fur hairs being continuously supplied with oil through the medulla to wet the pigment in the cortex with the result that the hairs of the fur stand out and flufi up as dothe hairs of natural live fur, and similarly will resist kinking or matting.
Another object of this invention is to provide a novel fur treating composition which may be readily and easily applied to the exterior surfaces of the pelts, as by spraying, and which will readily and thoroughly penetrate the epidermis and cuticle of the pelt and be retained within the interstices thereof to provide vital oils to the pelt for retaining motility in the fibers thereof over relatively long periods of time.
Another object of this invention is to provide a novel composition for providing furs with a high gloss or shine without oi1iness.-
Other objects of the invention will appear in the following description and appended claims. Before explaining the present invention in detail, it is to be understood that the invention is capable of other embodiments and of being practiced or carried out in various ways. It is also to be understood that the phraseolo-gy or terminology employed herein is for the purpose of description and not of limitation.
According to the present invention, the pelts are treated with an aqueous solution containing the novel composition of matter herein disclosed. This composition of matter is preferably in the form of an oil in water type emulsion and contains a tanning agent, such as tannic acid or oleic acid, a hydrocarbon wax, such as ozokerite, a silicone resin, a silicone oil and water. If desired, additional polishing waxes, such as carnauba or China-wood Wax, may also be added to the composition to provide an external polish and waterproof, although these ingredients are not essential to the purposes of the present invention.
The above composition is added to any water or aqueous solution used in processing the pelt. It may be added .to a tanning, soaking or dyeing bath or it may be added to the water used in subsequent shaping, stretching or cleaning operations. It is applied by any suitable means to the pelt being treated. One of the simplest and easiest means, after the pelt has been tanned and dried, is to spray the external surfaces of the pelt with water containing the composition. The materials in the emulsion readily penetrate the pelt skin and cover the fur hairs and are absorbed into the cellular structure of the corium of the skin.
The oil glands at the base of the hair of the pelt retain the fluid materials supplied in the novel composition of this invention, thus reducing the amount of severance and shedding of the hair. In addition, these oil glands serve as a reservoir for the oils contained in the emulsion, which oils are secreted during subsequent use of the pelt and flows through the medulla to wet the pigments of the hair and thus maintain the appearance and texture of the fur hairs in a natural, lifelike condition. After treatment with the novel composition of the present invention, the fur hairs remain flulfy and firm as in their natural live state and have a texture and coloration strikingly similar to the texture and coloration of live fur.
The novel composition of matter embodying the present invention is compounded in the physical form of an emulsion of the oil in water type. The disperse phase of the emulsion contains solutions or line dispersions of an organopolysiloxane, oil, an organopolysiloxane resin and the hydrocarbon waxes utilized. The continuous phase contains chiefly water or aqueous solutions which, if desired, may contain a tanning agent. A suitable emulsifier is employed to assist in the formation and stabilization of the emulsion. The emulsion may be further stabilized by treatment in a colloid mill or homogenizer.
Since the continuous phase is aqueous, the emulsion may be mixed as desired with water or other aqueous solution utilized in the particular fur treating operation. Due to the highly dispersed character of the organopolysiloxanes and the waxes in the emulsion, they are readily held in suspension in the extended continuous aqueous phase and are carried into both the skin and fur of the pelt. The emulsion is broken. by the removal of the water from the pelt, and the materials in the disperse phase of the emulsion are thus deposited on and in the pelt. The deposited materials in the skin portion of the pelt preserve motility of the fibers and fibrils and thus keep the entire pelt pliable. The oil glands are softened and supplied with oily materials which are supplied through the medulla to the interior of the fur hairs. The exterior of the fur hairs also absorbs athin coating or layer of the deposited materialsin the disperse phase of the emulsion.
I have found that both the silicone oil and silicone resin have advantageous properties when used separately for treating furs. However, when either of these are used alone, the fur has an undesirable oily feeling and appearance which makes the fur pelt unsatisfactory in subsequent use. .When combined, as in the present invention, in the required proportions and emulsified, the resulting composition has all of the inherent good qualities of the two silicone forms, without the disadvantages noted above.
The silicone oils are highly resistant to polymerization and maintain their fluidity and viscosity over long periods of time. In the emulsion composition of this invention, these oils apparently also protect the waxes used against such polymerization and thus maintain fluidity thereof while they remain in the interstices of the skin fibers and glands, prior to their passage through the medulla to feed and oil the hair. The low surface tension of the silicones assures their ready passage through the pores of the pelt and through the medulla and interior capillaries and pores of the fur hairs.
The emulsion embodying the present invention is generally of the oil in water type but actually is an emulsion system in which the dispersed phases are a plurality of different oil compositions, each of which has been separately emulsified. One of the emulsions contains a selected amount within the range of from 1% to 33% (by weight) of a mixed solution of a hydrocarbon-soluble organopolysiloxanc oil and resin, having from 1 to 3 aryl, alkyl or alkaryl radicals per silicon atom mixed with a selected amount within the range of from 15% to 50% (by weight) of a heated hydrocarbon solvent and the organopolysiloxane materials are dissolved therein. A volume of water equal in volume to the organopolysiloxane solution is heated to its boiling point and 20 parts by weight of an emulsifying agent suitable for forming emulsions of the oil in water type is added thereto. The water and emulsifying agent are thoroughly mixed and the heated organopolysiloxane-solvent and wax-solvent mixture is added thereto.
Both the organopolysiloxane oil and organopolysiloxane resin may be emulsified a the same time, as described above, by mixing them together in a suitable common hydrocarbon solvent. Benzol or xylol are suitable for this purpose. A small amount of turpentine may also be blended with the hydrocarbon solvent if desired to aid in the solubility of the organopolysiloxane resin.
The wax used in the second emulsion is also dis solved in a hot hydrocarbon solvent. The wax prefer ably is dissolved in hot xylol or hot benzol. Hot water is admixed with the solvent-wax mixture to form an emulsion which is then added to the combined organopolysiloxane oil and resin emulsion.
A third emulsion is added to the first two emulsions and contains in its dispersed phase primarily hydrocarbon waxes. Amechanical blending mechanism, such as a colloid mill or a homogenizer is preferably used to assure a uniform mixing of the materials. This produces a heavy white creamy emulsion which may then be blended with as much as 400 times its volume of hot water.
The following specific examples are illustrative of the present invention. in all instances, the amounts are stated in approximate parts by weight.
Example I A novel emulsion embodying the present invention was compounded by mixing three separately formed emul- The xylene was heated to approximately 150 F. and the ozokerite mixed thoroughly therein. The ammonium linoleate is then added to the resultant mixture. The
Water is heated to approximately 212 F. and, is then added slowly to the admixture while beingagitated to form a creamy, light emulsion.
Emulsion B consisted of:
In forming emulsion B, the polysiloxane oil and xylene are mixed together in one container. The polysiloxane resin and turpentine are mixed together in a separate container. The two resultant mixtures are then admixed and the tannic and oleic acids are added. The resulting mixture is stirred well. The triethanolamine is then mixed with the water and the organopolysiloxane mixtures are added slowly thereto, with stirring.
Emulsions A and B are then admixed while hot and stirred thoroughly.
Emulsion C consisted of:
Parts Carnauba wax 9 China-wood nil 2 Ammonium linoleate 14 Water 600 Tannic acid; Trace Oleic acid Trace Sulphonated castor oil Trace The wax should be melted at the lowest possible temperature and mixed with the China-wood oil. The hot water is then slowly added (about 30 cc. at a time) to the ammonium linoleate until a thinned solution is formed. 'The thinned ammonium linoleate solution is then added to the remaining boiling water. The tannic acid, oleic acid and the sulphonated castor oil are then added to this solution. The resulting solution is then slowly mixed into the melted wax and China-wood oil combination, stirring vigorously during the entire operation. The mixture is allowed to cool slowly, with continued vigorous agitation until a slightly heavy, creamy emulsion is produced.
The emulsions A, B, and C are then mixed thoroughly while hot to form the novel composition of matter embodying the present invention. If desired, any suitable water soluble dye or color may then be added to the emulsion.
Example II Emulsion E: 1 Parts Methyl (or ethyl) phenolsiloxane (oil) 8 Benzol 16 Methyl (or ethyl) phenolsiloxane (resin) 4 Turpentine 8 Tannic a id 5 Oleic acid Trace Morpholine oleate 20 Water 400 The silicone oil is mixed with its solvent, the silicone resin is mixed with the turpentine, and then the two are combined.
The water should be heated to the boiling point and the emulsifier slowly added, while the water is stirred Another example of a novel composition of matter embodying the present invention is an emulsion which is formed by combining with emulsion C of Example I, emulsions D and E as follows:
Parts Emulsion D:
Candelilla wax 4 Benzene 80 Morpholine oleate 14 Water 400 vigorously. The acids are then added. This final mixture is added slowly to the combined silicone combina tion, during which time the mixture is stirred vigorously. The above emulsions D and E are combined, while hot, with emulsion C of Example I.
Example III Another example of an emulsion embodying the present invention comprises emulsions F and G which are formed as above described in the. foregoing examples and are admixed with emulsion C of Example I to form the final product.
Emulsion F in this example consists of the following:
Parts Ouricuri wax 8 Toluol Hexaethylene glycol m noleate 14 Water 400 Emulsion G in this example consists of the following:
Parts Polyphenylsiloxane (oil) 8 Toluol 16 Polyphenylsiloxane (resin) 4 Turpentine 8 Tannic acid 5 Oleic acid Trace Morpholine stearate 20 Water 400 In any of the foregoing examples any of the separate emulsions may be substituted for a corresponding emulsion in the example. In place of emulsions A, D and F of the examples given, I may utilize either of the following emulsions:
Emulsion H: Parts Japan wax 3 Gasoline 7 70 Stearic acid 2 Triethanolamine 14 Water 400 Emulsion I:
Parafiin wax g 6 Benzol 70 Monpholine oleate V 14 Water 400 While in all instances it is preferable to use emulsion Cv of Example I as one of the emulsions in making the final composition, it is to be understood that this may be dispensed with in all instances where a final polishing or waxing of the exterior of the fur hairs is not required. The particular constituents of the final emulsion comprising the novel composition of matter embodying the present invention are selected and combined as may be required to meetthe anticipated requirements of the ultimate user. In all instances the emulsion is added to the Water or q asg utign used in the particular fur treating or Pratasi eratic .In h case 9 s g.
tanning or dyeing operation, the emulsion is added as a part of the soaking, tanning, bleaching .or dyeing bath. In stretching or shaping operations, the emulsion is added to the water used by the furrier and is sprayed, sprinkled or sponged onto the pelts. In cleaning operations, the emulsion may be added directly to the cleaning media employed. 1 No change in any of the mechanical processing of the pelts is required in using the novel product of the present invention, although the required time of the operation may be reduced in some instances, particularly where .time is required to secure thorough penetration of the pelts.
In instances in which the novel fur treating emulsion of the present invention was extended with water and sprayed onto, the outer surfaces of the fur pelts, it was found that tthe emulsion rapidly and thoroughly penetrated the surface of the skin. After drying, the pelts exhibited a highly flexible and pliable skin portion and the fur hair was fluify, soft, and natural appearing. The fur hairs had a desirable gloss and yet did not possess an undesirably oily texture.
After processing of these pelts into fur garments, using in the stretching and shaping operations Water to which the composition of the present invention had been added, the pelts upon drying retained their desirable appearance and texture. Moreover, the garments showed no sign of deterioration, such as due to shedding of the hair, anddid not require retreatment or additional glazing, such as has been found to be necessary with former fur treating compositions and methods.
The silicone oils referred to above are hydrocarbonsoluble organopolysiloxane polymers having linear or cyclic molecules, preferably methyl substituted. However, as is well known, these organopolysiloxanes may be substituted with aryl, alkyl or alkaryl radicals, generally 1 to 3 organic radicals per silicon atom. The alkyl radical is preferably methyl, ethyl, propyl or octadecyl. The aryl radical may be p'henyl, tolyl, chlorophenyl and xenyl. The alkaryl radical preferably is methyl-phenyl or ethylphenyl, of benzoyl.
The silicone resins suitable for use in the present invention areorganopolysiloxanes having a cross linking, and thus having a threedimensional network. Methyl and phenyl groupsare the most suitable organic modifiers, producing compounds such as dimethylpolysiloxane,
trimethylpolysiloxane and p'henymcthylpolysiloxane. However, these organopolys'iloxane resins may be substituted with aryl, alkyl or alkaryl radicals, generally containing 1 to 3 organic radicals per silicon atom.
As pointed out above, ozokerite is the most suitable hydrocarbon wax for use in combination 'with r the siloxane materials used in the emulsion of the present invention As is knovm, ozokerite is an amorphous hydrocarbon occurring naturally in the earth. The Wax is dispersed in the siloxane phase of the emulsion and is carried with thesiloxanes through the epidermis and cuticle when applied to the pelt. It remains dispersed within the siloxane phase of the emulsion and does not polymerize so that it is fed continually through the capillary passage in the hair. to lubricate and condition the hair. Ozokerite possesses the ability to sweat out the materials contained therein and liberate them through the hairs and the pelts. The wax-like elements of the ozokerite thus become progressively available to maintain a wax-like finish and gloss to the pelts for a relatively long period of time after application of the material to the pelts.
A suitable ozokerite has the following approximate properties:
Melting point 149-176 D. F. Specific gravity 0.85-0.95. Acid No. 0. Saponification No. 0.
Iodine No. 7.8-9.2.
Colors White, yellow,
Refractive index (60 C.) 1.440.
Dielectric constant 2.37-2.55.
Effective A. C. conductivity 10-24.
Volume resistivity 7-40.
Penetration 77 F. (100 g., 5 sec.) 14.
The use of such an ozokerite with the siloxane mate rials of the emulsion provides a modification of the natural oiliness of the siloxane materials and thus in addition to improving the appearance of the pelts, actually contributes to the material feel" and texture thereof. The combination of the ozokerite and siloxane materials preserve their ability to wet the hair pigments and to preserve pliability of the tanned skin. portion of the pelts.
Ozokerite is a preferred type of wax to use where optimum life of the treatment is desired. However, other waxes may be used as shown in the above examples. The modification of the action of the siloxanes in the emulsion with any of the named Waxes is similar to that above described with ozokerite, but is not quite as effective for the longer time periods during which the ozokerite re mains effective.
Any of a large number of emulsifying agents are suitable for use in the present invention. Ammonium lino leate has been found particularly suitable. However, any of the commercially available cationic, anionic or nonionic types may be used with the present invention. Examples of such materials are as follows: monoesters of polyethylene glycols and fatty acids of 12 to 18 carbon atoms, such as hexaethylene glycol monooleate; alkylate'd aryl polyether alcohols; acetates of n-primary amines having from 12 to 18 carbon atoms, such as n-dodecyl amine acetate, n-octadecyl amino acetate and n-octadecadienyl acetate; morpholine salts of fatty acids wherein the fatty acid contains 12 to 18 carbon atoms.
The addition of the. emulsified composition of matter embodying the present invention to Water or aqueous solutions used in the processing of fur pelts appears to increase the wetting power of the water or aqueous solution used. In dyeing, for example, a water soluble dye can be used and will be carried into parts of the pelt which normally are not wetted by water or aqueous solutions. If an oil soluble dye is desired, it can be incorporated in the oil phase of the emulsion and will be uniformly distributed throughout the pelt since the aqueous phase of the emulsion will rapidly and uniformly penetrate the pelt and carry with it the dispersed oil soluble dye. Tests h-ave shown that solutions containing the emulsion embodying the present invention wet rapidly and thoroughly both the keratin and mucine of the pelt as well as the other constituents thereof. Water or other aqueous solutions without the use of the emulsion embodying the present invention have a very limited wetting action, particularly on the keratin and mucine of the pelt.
Thus, in addition to providing skin preservation and fur beautification, the emulsion embodying the present invention accelerates the penetration of the pelt and distributes the active treating agents uniformly on the surface as well as through the pelt. After treatment, the cellular structure of the skin of the pelt contains the w-axes and siloxane constituents of the material which imparts a water resistance to the pelt. This is accomplished without upsetting the chemical properties of the pelt which permit subsequent stretching and shaping of the pelt by the use of water or aqueous solutions contain-. ing the emulsion embodying the present invention.
Also, in cleaning a pelt or a fur garment, the emulsion embodying the present invention acts to increase the effectivenes of the cleaning materials employed. Sawdust,
9 nut shells, sand, and similar types of so-called dry cleaning materials may be moistened with a water solution containing the emulsions embodying the present invention to expedite the cleaning operation. By thus moistening the materials used in cleaning, a more effective cleaning job is done in a shorter time and the fur is treated at the same time to achieve many of the beneficial results previously described.
In view of the incomplete state of the scientific knowledge underlying the present invention I do-not wish at this time to be limited to any particular theory to explain the novel results herein disclosed.
Having thus described my invention, what I claim is:
1.. A composition of matter adapted for use in treating fur pelts to provide a long-lasting, soft, pliable leather and a natural and pleasant appearing hair having a nonoily texture, comprising a combined emulsion of the oil in water type consisting of the admixture as separate emulsions of the following materials in the approximate parts by weight as follows:
. Parts Ozokerite 6 Xylene 100 Ammonium linoleate 14 Water 400 Dimethyl polysiloxane (oil) 8 Xylene 16 Dimethyl polysiloxane (resin) 4 Turpentine 8 Tannic *acid Trace Oleic a-cid Trace Triethanolamine 20 Water 400 C. Carnauba wax 9 China wood oil 2 Ammonium linoleate 14 Water 600 Tannic acid Trace Oleic acid Trace Sulphonated castor oil Trace 2. A composition of matter for use in treating furs to provide a long-lasting, soft, pliable leather and a natural and pleasant appearing hair having a non-oily texture, comprising a combined emulsion of the oil in water type containing the following approximate parts by weight of the following materials:
Water 400 3. The method of treating fur pelts to provide a longlasting, soft, pliable leather and natural and pleasant appearing hair having a non-oily texture comprising the novel steps of wetting the surfaces of the pelt with an oil in water type of emulsion containing in its disperse phase a hydrocarbon-soluble hydrocarbon polysiloxane oil and a hydrocarbon-soluble hydrocarbon polysiloxane resin and a hydrocarbon wax, and continuing said wetting until the composition has throughly penetrated the pores and interstices of the skin, thereafter drying the pelt and agitating the fur hairs.
4. The method of treating fur pelts in accordance with claim 3 and being further characterized in that the hydrocarbon polysiloxane oil and resin in the emulsion are substituted with a hydrocarbon radical selected from the group consisting of aryl, alkyl and alkaryl radicals, and have one to three radicals per silicone atom.
5. The method of treating fur pelts in accordance with claim 3 and being further characterized in that the hydrocarbon polysiloxane oil and resin utilized in the emulsions are dimethyl polysiloxanes.
6. The method of treating fur pelts in accordance with claim 3 and being further characterized in that the hydrocarbon wax utilized in the emulsion is ozokerite.
7. The method of treating fur pelts in accordance with claim 4 and being further characterized in that the hydrocarbon wax in said emulsion is ozokerite.
8. A treated fur pelt characterized by continued pliability of the skin and by the natural lustrous appearance and texture of the fur hair and containing a dispersed admixture of an hydrocarbon polysiloxane oil, an hydrocarbon polysiloxane resin and a wax deposited in the pores of the skin and distributed throughout and con tailned within the natural oil glands and hair ducts of the pe t.
9. A treated fur pelt as claimed in claim 8 and further characterized in that said wax is ozokerite.
10. A treated fur pelt as claimed in claim 8 and further characterized in that the said wax comprises a mixture of ozokerite and carnauba wax.
11. The method of treating fur pelts to provide a long lasting, soft, pliable leather and natural and pleasant appearing hair having a non-oily texture comprising the novel steps of wetting the surfaces of the pelt with an oil-in-water type of emulsion containing in its dispersed phase a hydrocarbon-soluble dimethyl polysiloxane oil, a hydrocarbon soluble dimethyl polysiloxane resin, and ozokerite, and continuing said wetting until the composition has thoroughly penetrated the pores and interstices of the skin, and thereafter drying the pelt and agitating the fur hairs.
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