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
  • C14C3/00—Tanning; Compositions for tanning
  • C14C3/02—Chemical tanning
  • C14C3/08—Chemical tanning by organic agents
  • C14C3/10—Vegetable tanning
• • 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
  • C14C3/00—Tanning; Compositions for tanning
  • C14C3/02—Chemical tanning
  • C14C3/04—Mineral tanning
  • C14C3/06—Mineral tanning using chromium compounds
• • 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
  • C14C3/00—Tanning; Compositions for tanning
  • C14C3/02—Chemical tanning
  • C14C3/08—Chemical tanning by organic agents
  • C14C3/16—Chemical tanning by organic agents using aliphatic aldehydes

Definitions

• the present invention relates to an improved dispersing agent composition for application in tanning. More particularly, the present invention relates to a dispersing agent composition to facilitate tanning of hides/skins without adding external water.
• the invention also provides a process for the preparation of the said dispersing agent composition.
• the composition of the invention finds enormous application in leather processing industry as an important auxiliary for the purpose of tanning of hides and skins without adding external water to the tanning bath. Thus the composition provides an eco-benign solution for leather tanning without generating effluent.
• degreasing for removal of excess fat is also carried out along with deliming and bating.
• the pelts are treated with 1-2L of water per kilo of pelt along with salt and acid to condition to a pH of 2.5-2.8 from the pelt pH of about 8.0.
• This operation is called pickling.
• the used medium is again discharged as effluent rich in salinity.
• the pickled pelts are then treated with about 2-3L of water per kilo of material along with 8% chromium based tanning agent and mixture of alkalies in a process called chrome tanning.
• the material obtained at the end of chrome tanning is called "Wet blue leather".
• the pH of the leather will be in the range of 3.8-4.0
• the pelts are sometimes treated with vegetable tannins instead of chromium.
• the leathers obtained through such process are called vegetable tanned leathers.
• the main objective of the present invention is to provide an improved dispersing agent composition for application in tanning, which obviates the limitations as stated above.
• Another objective is to provide a dispersing agent composition to facilitate any tannage without addition of external water.
• Yet another objective of the present invention is to provide a solution for the generation of effluent in leather tanning.
• the present invention provides a dispersing agent composition for application in tanning, wherein the said composition comprises alkali metal salt of organic acid having 1-6 carbon atoms;
• lyotropic agent optionally pre-treated with 50-100% w/w of reducing sugar
• ratio of (a):(b): (c) being in the range of 5:3:9 to 40: 1: 1 and 10% aqueous solution of the said composition exhibiting a pH in the range of 1.0 to 4.0.
• the alkali metal salt is selected from the group consisting of sodium formate, sodium acetate and sodium citrate.
• the acid used for pH adjustment is selected from the group consisting of sulfamic acid, citric acid, oxalic acid either individually or in any combination.
• the lyotropic agent used is selected from either Calcium chloride or urea.
• the derivative of diatomaceous earth is silica.
• the reducing sugar used is selected from the group consisting of glucose, galactose and fructose
• the present invention provides a process for preparation of the dispersing agent composition which comprises, optionally treating lyotropic agent with 50-100% w/w, of reducing sugar under stirring condition to obtain sugar pre-treated lyotropic agent, treating 2 to 9% w/w of lyotropic agent or sugar pre-treated lyotropic agent, as obtained in step (i), with alkali metal salt of organic acid, in presence of 1 to 3% w/w of diatomaceous earth or its derivative, added either simultaneously or in different succession, under continuous stirring, for a period of not less than 30 minutes and adjusting the pH of the dispersing agent composition in such a manner that the pH of 10% aqueous solution of the said composition is in the range of 1-4.
• the alkali metal salt used in the process is selected from the group consisting of sodium formate, sodium acetate and sodium citrate.
• the lyotropic agent used in the process is selected from either calcium chloride or urea.
• the present invention provides a tanning process using the dispersing agent as claimed in Claim 1, which comprises treating delimed pelt with the dispersing agent and tanning agent in the ratio 1: 1 to 1:20 for a period of not less than 3 hours to obtain tanned leather.
• Lyotropic agent is optionally treated with 50-100% w/w, of reducing sugar under stirring condition. 2 to 9% w/w of the resulting sugar pretreated lyotropic agent is added to the alkali metal salt of organic acid. The process involves an option of adding the said amount of lyotropic agent without subjecting the same to the pre-treatment of reducing sugar. 1 to 3% w/w of diatomaceous earth or its derivative is also added to the mixture. The additions take place either simultaneously or in different successions, under stirring conditions. After a period of not less than 30 minutes of treatment, the pH of the 10% aqueous solution of the resulting substrate is adjusted in the range of 1-4 to obtain the improved dispersing agent composition.
• the improved dispersing agent composition of the invention exhibits the following composition
• alkali metal salt of organic acid having carbon chain length in the range of one to three b) diatomaceous earth or its derivative c) lyotropic agent optionally pre-treated with 50-100% w/w,of reducing sugar, wherein(a):(b): (c) being in the range of 5 :3:9 to 40: 1: 1.
• the improved dispersing agent is used for tanning in the following manner
• Delimed pelt is treated with the improved dispersing agent and the tanning agent in the ratio of 1: 1 to 1:20 for a period not less than 3 hours to obtain tanned leather.
• the inventive step of the present invention lies in the incorporation of lyotropic agent and diatomaceous earth to the alkali metal salt of organic acid to ensure effecting uniform spreading of tanning agent, thereby providing a solution to the lack of consistency in tanning, as encountered in the prior art.
• the following examples are given by way of illustration only and therefore should not be construed to limit the scope of the present invention.
• the improved dispersing agent composition was then used for chrome tanning in the following manner :
• Example 3 15 gms of urea was mixed 10 gms of glucose to obtain glucose treted urea which was mixed with 5 gms of silica for 20 minutes. The resulting product was added to 200 gms of sodium acetate under stirring condition. After a period of 20 minutes, 20 gms of Oxalic acid was added to the above mixture with continuous stirring and the pH was adjusted to 4.0 to obtain the improved dispersing agent composition of the invention.
• Example 4 5 gms of urea was mixed with 2.5 gms of fructose for 15 minutes to obtain fructose treated urea which was then mixed with 5 gms of silica for 20 minutes. The resulting product was added to 50 gms of sodium citrate under stirring condition. After a period of 20 minutes, 30gms of citric acid was added to the above mixture with continuous stirring and the pH was adjusted to 1.0 to obtain the improved dispersing agent composition of the invention.
• the biological resource used in the invention are the delimed pelts obtained from the Supplier, Abdul kareem, Tanners, Traders of quality finished, Semi Finished Leathers and Hides & Skins, Chemicals and Tanning Materials, 57, Narayanan Street, Pudupet, India - 600 002
• the dispersion agent composition is suitable for any type of tannage.
• composition of the invention for leather tannage is suitable for all kinds of raw materials .
• composition of the invention for leather tannageensures complete elimination of use of water and common salt for tanning, thereby avoiding generation of tanning effluents.
• composition of the invention ensuresuniform and consistent results, when used for leather tannage.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Treatment And Processing Of Natural Fur Or Leather (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=64395396

Family Applications (1)

Country Status (5)

Family Cites Families (6)

• 2018
  • 2018-04-17 BR BR112019024702A patent/BR112019024702A2/pt not_active IP Right Cessation
  • 2018-04-17 EP EP18805112.2A patent/EP3635141A4/de not_active Withdrawn
  • 2018-04-17 CN CN201880044716.8A patent/CN110914460A/zh active Pending
  • 2018-04-17 WO PCT/IN2018/050222 patent/WO2018216029A1/en active Application Filing
• 2019
  • 2019-11-28 ZA ZA2019/07934A patent/ZA201907934B/en unknown

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