Classifications

• • C—CHEMISTRY; METALLURGY
  • C14—SKINS; HIDES; PELTS; LEATHER
  • C14C—CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
  • C14C11/00—Surface finishing of leather
• • C—CHEMISTRY; METALLURGY
  • C14—SKINS; HIDES; PELTS; LEATHER
  • C14C—CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
  • C14C11/00—Surface finishing of leather
  • C14C11/003—Surface finishing of leather using macromolecular compounds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F265/00—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00
  • C08F265/02—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00 on to polymers of acids, salts or anhydrides

Definitions

• the present invention concerns the technical sector of collagen-based substrates and notably hides, leathers, undressed hides and reconstituted leathers, and more specifically the use of acrylic polymers grafted with one or more proteinic derivatives or natural or synthetic fatty derivatives in the aim of allowing smoothing of the said substrate without the use of crosslinking agents, notably formol.
• the invention also concerns smoothing agents consisting of the said acrylic polymers grafted with one or more proteinic derivatives or natural or synthetic fatty derivatives.
• the invention also concerns collagen-based substrates, notably hides, leathers, undressed hides and reconstituted leathers smoothed using these said grafted acrylic polymers.
• the invention also concerns leather objects smoothed using these said grafted acrylic polymers.
• the first is a stage of sorting of the passes or hides or again substrates, which is undertaken in the abattoirs and/or in the tanneries, as desired by the client.
• the Applicant has chosen to use the word hide to designate all types of collagen-based substrates, including notably hides, leathers, undressed hides and reconstituted leathers.
• hide will be understood to include all the substrates mentioned above.
• the second stage still called river work
• the second stage constitutes a stage in the preparation of the sorted hide, which is still, at this stage, putrescible.
• This stage comprises firstly the soaking or dressing of the hide to clean the said hide, followed by the unhairing and liming of this cleaned hide to create points for mounting of the hide, which points will enable the various hide treatment additives to be fixed subsequently.
• the hide can be subjected to a skiving action followed by a shaving action corresponding to the removal of the subcutaneous part, which has no purpose, followed by actions of bating and finally of drenching, which is an enzymatic reaction to clean the keratin remains and the interfibrillary spaces.
• the hide is subjected to a third stage of treatment, a stage which is broken down firstly into pickling, i.e. acid conditioning of the hide to allow the penetration of tannins into the hide, and subsequently the tanning itself to make the hide rot-proof.
• This tanning of the hide habitually makes use of mineral derivatives such as, notably, chromium-, aluminium- or zirconium-based salts, together with organic derivatives such as hydrolysable vegetal tannins such as, for example, glucosides of the chestnut tree, Vallonnee, vinegar plant or Myrobolam types, or of organic derivatives such as condensed vegetal tannins, including among others catechic oligomers of the Quebrach, mimosa or gambir type.
• mineral derivatives such as, notably, chromium-, aluminium- or zirconium-based salts
• organic derivatives such as hydrolysable vegetal tannins such as, for example, glucosides of the chestnut tree, Vallonnee, vinegar plant or Myrobolam types, or of organic derivatives such as condensed vegetal tannins, including among others catechic oligomers of the Quebrach, mimosa or gambir type.
• organic derivatives can also be synthetic tannins which can replace the vegetal tannins. They are then called substitution tannins.
• substitution tannins are compounds rich in OH ⁇ in their structure and are mainly formol phenolic or naphtol-phenol condensates.
• These synthetic organic derivatives can also be secondary tannins used as a supplement to other tannins. They have less tanning power, but have other properties, notably including dispersing, filling or “full” properties, or lightening or other properties.
• These secondary tannins are also sulfonic naphthalene condensates, sulfonic aromatic acid, urea-formol, or again precondensed melamine and other condensates, but are also other than synthetic tannins such as, notably, aldehydes of the formol type, glyoxal, glutaraldehyde, aldehyde derivatives mainly multi-function products such as aldehyde-alcohols, phosphoniums, fatty chain sulfochlorides and other sulfochlorate paraffins.
• the fourth stage of the process is undertaken, consisting in all the operations undertaken after tanning, which is called currying.
• This currying includes the wet operations such as curing, which consists in allowing the hides to stay stacked for 24 hours to perfect the tanning, neutralisation, retanning, dyeing, nourishing agents to soften the hide, and mechanical operations such as draining, drying, tempering or re-wetting, staking, which consists in stretching the hide to soften it at a degree of humidity of around 23% to 28%, framing, which consists in stretching the staked hides on to frames to flatten them, and sliding these frames into a drying machine to eliminate the previous moisture, trimming, which is a manual operation consisting of eliminating the frayed edges of the hide which make the skin unpresentable, and smoothing.
• wet operations such as curing, which consists in allowing the hides to stay stacked for 24 hours to perfect the tanning, neutralisation, retanning, dyeing, nourishing agents to soften the hide
• mechanical operations such as draining, drying, tempering or re-wetting, staking, which consists in stretching the
• This mechanical smoothing operation consists in smoothing the hide using a metal, glass or agate cylinder, or cylinder of any other material, or again using a plate or any other method for shining the hide.
• This operation is accompanied by a heating which encourages the shine to “rise”, since it is undertaken on a dry hide during currying, after trimming and framing, or again after the fifth stage of the process, which is the finishing of the hide on conclusion of manufacture.
• casein crosslinking agent notably formol
• the specifications sheet generally applied requires that the formol contents in the hides have:
• the handling problems are constituted by the need to use casein and then to spray, during a second stage, the crosslinking agent of the said casein.
• the Applicant has found that the use, on collagen-based substrates, and notably hides, leathers, undressed hides and reconstituted leathers, of acrylic polymers grafted with one or more proteinic derivatives or natural or synthetic fatty derivatives enables the abovementioned problems posed to arisen to the skilled man in the art to be resolved; i.e. allows firstly problems relating to manipulation due to the use of casein followed by a spraying of crosslinking agent to be avoided, secondly allows all or part of the casein crosslinking agent, notably formol, to be eliminated, and thirdly enables the smoothing operation before the finishing operation, giving by this means the advantage of obtaining the smoothed appearance, which will enhance the finishing operation.
• grafted acrylic polymers are acrylic polymers grafted with one or more proteinic derivatives or natural or synthetic fatty derivatives.
• This use is, preferably, characterised in that it is used at a rate of 0.8% to 6% by dry weight, relative to the so-called “wet blue” support weight, and more particularly at a rate of 1.2% to 2.4% by dry weight, relative to the so-called “wet blue” support weight, of the said acrylic polymers grafted with one or more proteinic derivatives or of the natural or synthetic fatty derivatives.
• the weight of the so-called “wet blue” support is the weight of the hide after the river work, chromium tanning, wringing and skiving operations.
• these grafted acrylic polymers result from various radical polymerisation processes in the presence of the proteinic derivatives or of the natural or synthetic fatty derivatives for grafting.
• use as a smoothing agent of these polymers resulting from homopolymerisation or radical copolymerisation of unsaturated ethylene monomers in the presence of a proteinic derivative or derivatives, or from the natural or synthetic fatty derivative or derivatives for grafting is characterised in that the said agent is a product of radical polymerisation of at least one of the monomers from among: acrylic acid, methacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic anhydride and/or 2-acrylamido-2-methyl-1-propane sulfonic acid, 2-methacrylamido-2-methyl-1-propane sulfonic acid, 3-methacrylamido-2-hydroxy-1-propane sulfonic acid, allylsulfonic acid, methallylsulfonic acid, allyloxybenzene sulfonic acid, methallyloxybenzene sulfonic acid, 2-hydroxy-3-(2-propenyloxy) propane
• acrylic or methacrylic acid esters are chosen from alkyloxypolyalkylene glycol acrylate or methacrylate and particularly is methoxypolyethylene glycol methacrylate.
• polymers resulting particularly from homopolymerisation or from radical copolymerisation of the monomers previously listed in the presence of the proteinic derivative or derivatives or from the natural or synthetic fatty derivatives, or from their mixtures mentioned above, are characterised even more particularly in that the mass rate of proteinic derivatives or of natural or synthetic fatty derivatives, relative to the total quantity of monomers, is between 2.5% and 40%, and preferably between 5% and 10%.
• polymers can be obtained by radical polymerisation or copolymerisation of the abovementioned monomers in the acid state, partially neutralised or totally neutralised, and preferably in the acid state in a polymerisation medium which can be water, one of the alcohols or a water-alcohol mixture, or again one of the solvents chosen from methanol, ethanol, propanol, isopropanol, the butanols, or mixtures of them, or again dimethylformamide, dimethylsulfoxide, tetrahydrofuran, acetone, methylethylketone, ethyl acetate, butyl acetate, hexane, heptane, benzene, toluene, xylene, halogenated solvents such as carbon tetrachloride, chloroform, methylene chloride, or again the glycol monopropylene ethers, or mixtures of them and their analogues.
• a polymerisation medium can
• the skilled man in the art will adapt the pH of the polymerisation medium according to the proteinic derivative or derivatives, or of the natural or synthetic fatty derivative or derivatives, or according to the mixtures of thereof used in this polymerisation reaction.
• neutralisation agents are chosen either from the group constituted by the compounds containing alkaline cations, particularly sodium and potassium, or again lithium, ammonium, or indeed the primary or secondary aliphatic and/or cyclic amines such as, for example, the ethanolamines, mono- and diethylamine, or again cyclohexylamine, or from the group constituted by the compounds containing alkaline-earth divalent cations, particularly magnesium and calcium, or again zinc, or the group constituted by the compounds containing trivalent cations, in particular aluminium, or again by certain compounds containing cations of higher valences, or are a mixture of at least two of the abovementioned agents.
• the homopolymer or copolymer produced from the polymerisation reaction in the presence of the proteinic derivative or derivatives or of the natural or synthetic fatty derivative or derivatives may be treated and separated into several phases, according to static or dynamic processes known to the skilled man in the art, by one or more polar solvents belonging notably to the group constituted by water, methanol, ethanol, propanol, isopropanol, the butanols, acetone, tetrahydrofuran, or mixtures of thereof.
• One of the phases then corresponds to the polymer used according to the invention as a smoothing agent.
• the invention also concerns smoothing agents consisting of the said acrylic polymers grafted with the said proteinic derivatives or natural or synthetic fatty derivatives.
• the smoothing agents according to the invention are characterised in that they are products of radical polymerisation of at least one of the monomers from among: acrylic acid, methacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic anhydride and/or 2-acrylamido-2-methyl-1-propane sulfonic acid in acid or partially neutralised form, 2-methacrylamido-2-methyl-1-propane sulfonic acid in acid or partially neutralised form, 3-methacrylamido-2-hydroxy-1-propane sulfonic acid in acid or partially neutralised form, allylsulfonic acid, methallylsulfonic acid, allyloxybenzene sulfonic acid, methallyloxybenzene sulfonic acid, 2-hydroxy-3-(2-propenyloxy) propane sulfonic acid, 2-methyl-2-propene-1-sulfonic acid, ethylene sulfonic acid, propene sulfonic acid,
• the smoothing agent according to the invention is characterised in that the acrylic or methacrylic acid esters are chosen from alkyloxypolyalkylene glycol acrylate or methacrylate and particularly is methoxypolyethylene glycol methacrylate.
• the smoothing agents according to the invention are characterised in that the mass rate of the proteinic derivatives or of the natural or synthetic fatty derivatives or of mixtures of thereof, relative to the total quantity of the monomers, is between 2.5% and 40%, preferably between 5% and 10%.
• the smoothing agent according to the invention obtained by radical polymerisation or copolymerisation of the abovementioned monomers, is in the acid state, or in the partially neutralised state, or the totally neutralised state, and is preferably in the acid state, i.e. a pH of under 7.
• the neutralisation agents are chosen from among those previously described.
• the smoothing agent according to the invention produced from the polymerisation reaction in the presence of the proteinic derivative or derivatives or from the natural or synthetic fatty derivative or derivatives may, as previously described, be treated and separated into several phases.
• the invention also concerns collagen substrates smoothed using the said acrylic polymers grafted with the said proteinic derivative or derivatives or natural or synthetic fatty derivatives.
• hides are characterised in that they contain the said acrylic polymers grafted with the said proteinic derivatives or natural or synthetic fatty derivatives or mixtures of thereof, and are characterised more particularly in that they contain 0.8% to 6% by dry weight, relative to the weight of the so-called “wet blue” support, and particularly 1.2% to 2.4% by dry weight relative to the weight of the so-called “wet blue” support, of the said acrylic polymers grafted with proteinic derivatives or natural or synthetic fatty derivatives.
• the invention also concerns leather objects smoothed using the said acrylic polymers grafted with the said proteinic derivative or derivatives, or natural or synthetic fatty derivatives.
• the aim of this example is to highlight is also the shining properties obtained through the use of acrylic polymers grafted with one or more proteinic derivatives or natural or synthetic fatty derivatives according to the invention.
• a goat's hide is prepared called “wet blue” after the river works, chromium tanning, wringing and skiving operations.
• the “wet blue” hide is then weighed, and this weight is the reference weight for the stages of neutralisation, retanning, dyeing and nourishment which follow.
• the “wet blue” hide is introduced in a cleaning drum at 40° C. containing a cleaning bath consisting of 150% by weight of water relative to the weight of the “wet blue” hide and of 1% by weight, relative to the weight of the “wet blue” hide, of the cleaning agent Actol DB sold by the company ATC.
• This bath containing the hide is stirred for 20 minutes at a speed of between 10 and 12 revolutions per minute, before being emptied from the drum.
• the stage of neutralisation at 35° C. is then undertaken up to a pH of 4.5, by addition, into the drum, of the neutralising medium, consisting of 100% by weight of water relative to the weight of the “wet blue” hide, and 1% by weight, relative to the weight of the “wet blue” hide, of the neutralising agent Actan NH sold by the company ATC.
• the neutralising medium consisting of 100% by weight of water relative to the weight of the “wet blue” hide, and 1% by weight, relative to the weight of the “wet blue” hide, of the neutralising agent Actan NH sold by the company ATC.
• the neutralising bath is, in its turn, emptied from the drum to allow room for the retanning stage.
• 50% by weight of water is added relative to the weight of the “wet blue” hide and 3% by weight, relative to the weight of the “wet blue” hide, of a black colouring agent sold by the company ATC under the name Dyacor Black ANT, and it is then stirred 3 times 10 minutes, at a speed of between 10 and 12 revolutions per minute, before adding 50% by weight of water, relative to the weight of the “wet blue” hide, and 1.5% by weight, relative to the weight of the “wet blue” hide, of a nourishment for hide sold by the company ATC under the name Actoil NM.
• the whole mixture is stirred for 20 minutes at the same speed, before adding 10% by weight, relative to the weight of the “wet blue” hide, of a vegetal mimosa tannin sold by the company Seta under the name Seta Sun.
• the whole mixture is also stirred for one hour at the same speed before adding 1% by weight, relative to the weight of the “wet blue” hide, of formic acid.
• the bath After adding formic acid and stirring for 20 minutes at a speed of between 10 and 12 revolutions per minute, the bath is emptied and then rinsed.
• the retanning operation then continues for all tests by adding at 50° C. of 50% by weight of water, relative to the weight of the “wet blue” hide, and of 0.1% by weight, relative to the weight of the “wet blue” hide, of a biocide sold by the company ATC under the name Biocide C3, and then by stirring the mixture for 5 minutes at a speed of between 10 and 12 revolutions per minute.
• the whole mixture is then stirred for 10 minutes at the same speed before adding 1% by weight, relative to the weight of the “wet blue” hide, of a nourishment for hide sold by the company ATC under the name Actoil VI, 2.5% by weight, relative to the weight of the “wet blue” hide, of another nourishment for hide sold by the company ATC under the name Actoil SGC, and finally before adding 0.5% by weight, relative to the weight of the “wet blue” hide, of a final nourishment for hide sold by the company ATC under the name Actoil NLP.
• the various tests of the example then implement the various polymers to be tested as a smoothing agent through the addition into the drum of the various agents for testing under stirring at 10 to 12 rpm for 30 minutes.
• these agents have been implemented, a final addition of 1% of formic acid by weight relative to the weight of the “wet blue” hide is made.
• This test is a control test which implements 1.2% by dry weight, relative to the weight of the “Wet blue” hide, of an acrylic acid homopolymer.
• the value of the shine obtained is equal to 4.1.
• This test illustrates the invention and implements 1.2% by dry weight, relative to the weight of the “Wet blue” hide, of a casein-grafted acrylic acid polymer in a weight ratio of equal to 92.5% acrylic acid and 7.5% casein.
• the value of the shine obtained is equal to 4.8.
• This test illustrates the invention and implements 4.5% by dry weight, relative to the weight of the “Wet blue” hide, of a casein-grafted acrylic acid polymer in a weight ratio of equal to 97.5% acrylic acid and 2.5% casein.
• the value of the shine obtained is equal to 5.3.
• This test illustrates the invention and implements 0.8% by dry weight, relative to the weight of the “Wet blue” hide, of a casein-grafted acrylic acid polymer in a weight ratio of equal to 80% acrylic acid and 20% casein.
• the value of the shine obtained is equal to 4.7.
• This test illustrates the invention and implements 1.2% by dry weight, relative to the weight of the “Wet blue” hide, of a casein-grafted acrylic acid polymer in a weight ratio of equal to 95% acrylic acid and 5% casein.
• the value of the shine obtained is equal to 5.2.
• This test illustrates the invention and implements 1.2% by dry weight, relative to the weight of the “Wet blue” hide, of a casein-grafted acrylic acid polymer in a weight ratio of equal to 90% acrylic acid and 10% casein.
• the value of the shine obtained is equal to 8.1.
• This test illustrates the invention and implements 0.9% by dry weight, relative to the weight of the “Wet blue” hide, of a linseed oil-grafted acrylic acid polymer in a weight ratio of equal to 90% acrylic acid and 10% linseed oil.
• This test illustrates the invention and implements 1.8% by dry weight, relative to the weight of the “Wet blue” hide, of a linseed oil-grafted acrylic acid polymer in a weight ratio of equal to 90% acrylic acid and 10% linseed oil.
• the value of the shine obtained is equal to 6.3.
• This test illustrates the invention and implements 1.8% by dry weight, relative to the weight of the “Wet blue” hide, of a casein-grafted acrylic acid polymer in a weight ratio of equal to 90% acrylic acid and 10% casein.
• This test illustrates the invention and implements 1.8% by dry weight, relative to the weight of the “Wet blue” hide, of a polymer of acrylic acid and methacrylic acid grafted with lecithin, in a weight ratio of equal to 45% acrylic acid, 45% methacrylic acid and 10% lecithin.
• the value of the shine obtained is equal to 5.5.
• This test illustrates the invention and implements 1.8% by dry weight, relative to the weight of the “Wet blue” hide, of a linseed oil-grafted acrylic acid polymer in a weight ratio of equal to 60% acrylic acid and 40% linseed oil.
• the value of the shine obtained is equal to 4.9.
• This test illustrates the invention and implements 2.3% by dry weight, relative to the weight of the “wet blue” hide, of a copolymer, of pH 5, of acrylic acid grafted with olein in a weight ratio of equal to 75.6% acrylic acid, 14.4% maleic anhydride and 10% olein.
• This test illustrates the invention and implements 2.3% by dry weight, relative to the weight of the “wet blue” hide, of a copolymer, of pH 5, of acrylic acid grafted with casein in a weight ratio of equal to 85.5% acrylic acid, 9.5% 2-acrylamido-2-methyl-1-propane sulfonic acid and 5% casein.
• the value of the shine obtained is equal to 8.6.
• This test illustrates the invention and implements 2.3% by dry weight, relative to the weight of the “wet blue” hide, of a copolymer, of pH 5, of acrylic acid grafted with linseed oil in a weight ratio of equal to 68% acrylic acid, 15.3% acrylamide, 1.7% sodium methallylsulfonate and 15% linseed oil.
• the value of the shine obtained is equal to 5.6.
• This test illustrates the invention and implements 2.3% by dry weight, relative to the weight of the “wet blue” hide, of a copolymer, of pH 5, of acrylic acid grafted with lanolin in a weight ratio of equal to 73.6% acrylic acid, 13.8% methacrylic acid, 4.6% methacrylamide and 8% lanolin.
• the value of the shine obtained is equal to 6.1.
• This test illustrates the invention and implements 2.3% by dry weight, relative to the weight of the “wet blue” hide, of a copolymer, of pH 6.5, of methacrylic acid grafted with ricin oil in a weight ratio of equal to 81% methacrylic acid, 4.5% butyl acrylamide, 4.5% styrene and 10% ricin oil.
• the value of the shine obtained is equal to 10.1.
• This test illustrates the invention and implements 2.3% by dry weight, relative to the weight of the “wet blue” hide, of a polymer, of pH 5, of acrylic acid grafted with fish oil in a weight ratio of equal to 80% of acrylic acid and 20% fish oil.
• This test illustrates the invention and implements 2.3% by dry weight, relative to the weight of the “wet blue” hide, of a copolymer, of pH 5, of acrylic acid grafted with copra oil in a weight ratio of equal to 76% acrylic acid, 4.75% ethylene glycol methacrylate phosphate, 14.25% methoxypolyehthylene glycol methacrylate of molecular weight 750 and 5% copra oil.
• the value of the shine obtained is equal to 8.7.
• This test illustrates the invention and implements 2.3% by dry weight, relative to the weight of the “wet blue” hide, of a copolymer, of pH 5, of acrylic acid grafted with neat's foot oil in a weight ratio of equal to 85.5% acrylic acid, 4.5% vinyl acetate and 10% neat's foot oil.
• the value of the shine obtained is equal to 8.1.
• This test illustrates the invention and implements 1.8% by dry weight, relative to the weight of the “wet blue” hide, of a polymer, of pH 5, of acrylic acid grafted with casein and linseed oil in a weight ratio of equal to 90% of acrylic acid, 5% casein and 5% linseed oil.
• the value of the shine obtained is equal to 6.0.
• This test illustrates the invention and implements 0.9% by dry weight, relative to the weight of the “wet blue” hide, of a polymer, of pH 5, of acrylic acid grafted with lecithin in a weight ratio of 90% acrylic acid and 10% lecithin and 0.9% by dry weight, relative to the weight of the “wet blue” hide, of a polymer, of pH 5, of acrylic acid grafted with lanolin in a weight ratio of equal to 90% acrylic acid and 10% lanolin.
• This shine value enables the natural appearance of the hide to be preserved.

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• General Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
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• Polymers & Plastics (AREA)
• Treatment And Processing Of Natural Fur Or Leather (AREA)

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• 2002
  • 2002-02-28 FR FR0202527A patent/FR2836485B1/fr not_active Expired - Fee Related
• 2003
  • 2003-02-20 KR KR10-2004-7013255A patent/KR20040094733A/ko not_active Application Discontinuation
  • 2003-02-20 EP EP03717418A patent/EP1481099A1/fr not_active Withdrawn
  • 2003-02-20 AU AU2003222585A patent/AU2003222585A1/en not_active Abandoned
  • 2003-02-20 WO PCT/FR2003/000565 patent/WO2003072834A1/fr not_active Application Discontinuation
  • 2003-02-20 US US10/503,132 patent/US20050155157A1/en not_active Abandoned
  • 2003-02-20 CA CA002476649A patent/CA2476649A1/fr not_active Abandoned

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