US3174817A - Chrome-acetate complex tannage - Google Patents

Chrome-acetate complex tannage Download PDF

Info

Publication number
US3174817A
US3174817A US148245A US14824561A US3174817A US 3174817 A US3174817 A US 3174817A US 148245 A US148245 A US 148245A US 14824561 A US14824561 A US 14824561A US 3174817 A US3174817 A US 3174817A
Authority
US
United States
Prior art keywords
chrome
tanning
chromium
curve
acetate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US148245A
Other languages
English (en)
Inventor
Spahrkas Heinrich
Mauthe Gustav
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bayer AG
Original Assignee
Bayer AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bayer AG filed Critical Bayer AG
Application granted granted Critical
Publication of US3174817A publication Critical patent/US3174817A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • C14C3/04—Mineral tanning
    • C14C3/06—Mineral tanning using chromium compounds

Definitions

  • the present invention relates to and has as its object a new and useful process for the preparation of chromium tanned leather.
  • Tanning with basic sulphates of trivalent chromium is conventionally carried out according to the following process:
  • the initial tanning is carried out with small-particled low-basic chrome liquors, followed by buffering with alkalies (sodium carbonate, sodium brcarbonate, sodium sulphite, and the like) in order to increase the basicity and thus of the particle size and astringency.
  • alkalies sodium carbonate, sodium brcarbonate, sodium sulphite, and the like
  • these chromium compounds possess an extremely strong masking eliect when they are used in the tanning process in a highly concentrated form as thickened chrome lyes or as powdered carefully dried chromium products.
  • These chromium complex compounds possess, as has further been found, in this method of application the property of converting themselves during the tanning process due to the presence of the moisture of the hides or on account of the tanning liquor added, whereby the initially strongly masking effect gradually disappears and chromium compounds are formed which are fully effective in tanning.
  • the most important factor of this process is the uniformity with which the tanning activity increases. The rate of this uniform process is controllable by the temperature and by the quantity of added water.
  • the later conversion process in the course of tanning may be accelerated by admixing sodium carbonate, sodium bicarbonate, sodium sulphite, etc., to the powdered chromium compounds.
  • This process according to the invention results in a very rapid diffusion of the initially strongly masked chromium complex compounds through the hide or leather.
  • the ever self-increasing tanning efiect of the chromium compounds during the course of tanning eliminates the disadvantages brought about by the usual basification in the conventional processes.
  • the tannings may be conducted at a hi' h basicity even from the start without showing the disadvantages, such as chrome stains on the surface of the leather, to be expected by tanning technologists, thus rendering the usual neutralisation after chrome tanning unnecessary.
  • By appropriately conducting the tanning process temperature, adjustment of basicity
  • very high amounts of chromium can be taken up and bound by the leather in extremely brief tanning times.
  • a surprisingly good distribution of chromium in the leather is attained by the process according to the invention.
  • chrome leather is obtained with excellent properties such as a full soft handle and excellent smoothness, quality and tightness of the grain, whilst avoiding completely or partially otherwise usual working proccsses such as pickling, basification and neutralising.
  • FIGURE 1 The great difference between the known and the new process is simplest illustrated by FIGURE 1.
  • the vertical axis indicates the flocculation point expressed in percent basicity whereas the horizontal axis indicates the time of ageing in hours.
  • Curve 1 illustrates a conventional chrome sulphate stock solution (6% Cr O 33% basicity)
  • curve 2 illustrates a chrome sulphate stock solution as 1 but boiled with 0.2 mol sodium acetate/ atom chrome
  • curve 3 illustrates chrome sulphate lye at 33% basicity, thickened to 3 18% Cr O treated with 0.2 mol sodium acetate/atom chrome and dried under mild conditions
  • curve 4 illustrates a chrome sulfate product as 3 but without addition of sodium acetate.
  • the flocculation points have been established in percentages basicity upon dissolving or diluting in the cold state to 2.6% chromium oxide in various ageing stages by titrating 100 ml. of chrome solution with 3 N sodium carbonate. The ageing temperature is 30 C. The titration rate is 2 ml. feed in seconds.
  • Curve 1 represents the type of a conventional unmasked chromium sulphate stock solution at 33% basicity.
  • Curve 2 shows a chromium sulphate stock solution boiled with 0.2 mol acetate-atom chrome. Both curves show later during ageing the same character of curve and differ in the flocculation point only immaterially. Fundamentally different is the course of curve 3 which likewise represents a chromium sulphate solution treated with 0.2 mol acetate/atom chrome, which, however, is thickened to 18% chromium oxide prior to ageing, or subsequently concentrated to chromium oxide by mild drying.
  • the optimum amount required for the aforesaid tanning course is a typical value which may substantially deviate from the indicated optimum acetate amount.
  • water-soluble monocarboxylic acids such as acetic acids
  • Water-soluble dicarboxylic acids and watersoluble hydroxy-carboxylic acids are found suitable for the purpose of the invention.
  • FIGURE 2 shows the quantitative dilferences between the formate masking and acetate masking by way of example.
  • Curve 1 shows the desired type of a chromium sulphate solution treated with 0.2 mol acetate/ atom chrome thickened to a content of 18% chromium oxide, or concentrated to about 25% chromium oxide by mild drying.
  • curve 2 which shows an analogous chromium sulphate solution solution but treated with 0.2 mol formate/ atom chrome has an essentially flatter course of curve.
  • Curve 1 illustrates a chromium sulphate lye at 33% basicity thickened to 18% Cr O treated with 0.2 mol sodium acetate/ atom chrome and dried under mild conditions (identical with curve 3 of FIGURE 1).
  • Curve 2 illustrates a chromium sulphate product as 1 but with addition of 0.2 mol sodium formate/atom chrome and curve 3 illustrates the chromium sulphate product as 1 but with addition of 0.6 mol sodium formate/atom chrome.
  • the chromium complex compounds required for this process are produced in the simplest manner by reacting chromic sulphate lyes thickened to a content of at least 15% chromium oxide, with the inventively used watersoluble organic acids or alkali metal salts thereof at an elevated temperature, or drying under mild conditions the chrome lyes treated with the indicated amounts of masking agents, provided they are powdered products.
  • the new tanning process is valuable for the full chrome tanning of pelts as Well as for chrome pretarmings for leather to be tanned in a combined manner and for aftertannings, also in combination with other after-tanning agents.
  • Example 1 100 parts by weight of calf pelts are drummed in a tumbler for 6 hours, after preliminary work usually carried out for upper leather (liming, de-liming, bating), without pickle, with 100 parts by weight of water and 12 parts by weight of chromium complex tanning agent dried under mild conditions and described below. These tanning agents are added to the tanning liquor undissolved and in one portion. The usual basification of the chrome tanning is not necessary. The leathers are horsed up after tanning and further processed in the usual way.
  • composition of the chrome complex substances used for tanning 100 parts by weight of a chromic sulphate lye at 33% Schorlemmer basicity, thickened to 18% chromium oxide content, were treated at C. with stirring with (a) 4 parts by weight of anhydrous sodium acetate, or
  • glycollic acid in the form of 70% acid, neutralised with 2.2 parts by weight of sodium hydroxide
  • the chromium complex tanning agents formed after a reaction of several hours are dried under mild conditions.
  • Example 2 Work is carried out as indicated under (1a)., (1b), (1c), (1d), (1e) or (If) but with addition of 18 parts by weight of undiluted non-spray-dried chrome complex lye to the calf pelts.
  • a leather is obtained of a quality comparable to that described above.
  • Example 3 parts by weight of calf pelts are drummed for 6 hours, after preliminary work usually carried out for upper leather (liming, tie-liming, hating, pickling), with 100 parts by weight of water and in each case with 14 parts by weight of the chromium complex tanning agents dried under mild conditions and described below. These tanning agents are added to the tanning liquor in one portion, in an undissolved state. The leathers are horsed up after tanning and further processed without basification and neutralisation in the usual way.
  • composition of the chromium complex tanning agents used for tanning is as described under (la), (lb), (10), (1d) or (1 However, 100 parts by weight of the tanning agents dried under mild conditions are mixed with 16 parts by weight of anhydrous sodium carbonate.
  • a method of chrome tanning pelts comprising contacting damp pelts with an active amount of a chromium sulphate tanning agent selected from the class consisting of (a) highly concentrated chromium sulphate solution and (b) dried powdered chromium sulphate, the active material having not less than 15% chromic oxide and about .2-.3 mol of coordinatively bound acetic acid radicals per atom of chrome.
  • a chromium sulphate tanning agent selected from the class consisting of (a) highly concentrated chromium sulphate solution and (b) dried powdered chromium sulphate, the active material having not less than 15% chromic oxide and about .2-.3 mol of coordinatively bound acetic acid radicals per atom of chrome.

Landscapes

  • 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)
  • Detergent Compositions (AREA)
US148245A 1960-10-28 1961-10-27 Chrome-acetate complex tannage Expired - Lifetime US3174817A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEF32434A DE1230170B (de) 1960-10-28 1960-10-28 Gerbverfahren

Publications (1)

Publication Number Publication Date
US3174817A true US3174817A (en) 1965-03-23

Family

ID=7094635

Family Applications (1)

Application Number Title Priority Date Filing Date
US148245A Expired - Lifetime US3174817A (en) 1960-10-28 1961-10-27 Chrome-acetate complex tannage

Country Status (3)

Country Link
US (1) US3174817A (no)
DE (1) DE1230170B (no)
GB (1) GB969865A (no)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3254938A (en) * 1962-08-29 1966-06-07 Rodriguez Pedro Villa Leather tanning
US4211529A (en) * 1977-09-03 1980-07-08 Bayer Aktiengesellschaft Chrome-tanning
US4298344A (en) * 1979-03-07 1981-11-03 Bayer Aktiengesellschaft Age resistant chrome tanning agents
US4312632A (en) * 1979-07-24 1982-01-26 Ottavio Torrini Method of tanning skins or hides
US20090158530A1 (en) * 2007-12-25 2009-06-25 Soda Sanayi A.S. Use of chromium complex in the leather industry
US11851722B2 (en) 2018-01-16 2023-12-26 Tfl Ledertechnik Gmbh Chromium tanning agents

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3306374A1 (de) * 1983-02-24 1984-08-30 Basf Ag, 6700 Ludwigshafen Verfahren zum gerben von haeuten mit einem hochbasischen chromgerbstoff
WO2003072833A1 (en) * 2002-02-28 2003-09-04 Council Of Scientific And Industrial Research A process for making chrome tanned leathers

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2999003A (en) * 1959-02-06 1961-09-05 Du Pont Leather tanning agent and process

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2999003A (en) * 1959-02-06 1961-09-05 Du Pont Leather tanning agent and process

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3254938A (en) * 1962-08-29 1966-06-07 Rodriguez Pedro Villa Leather tanning
US4211529A (en) * 1977-09-03 1980-07-08 Bayer Aktiengesellschaft Chrome-tanning
US4298344A (en) * 1979-03-07 1981-11-03 Bayer Aktiengesellschaft Age resistant chrome tanning agents
US4312632A (en) * 1979-07-24 1982-01-26 Ottavio Torrini Method of tanning skins or hides
US20090158530A1 (en) * 2007-12-25 2009-06-25 Soda Sanayi A.S. Use of chromium complex in the leather industry
WO2009082361A1 (en) * 2007-12-25 2009-07-02 Soda Sanayi A. S. Modified chromium complex and its use in leather industries.
US11851722B2 (en) 2018-01-16 2023-12-26 Tfl Ledertechnik Gmbh Chromium tanning agents

Also Published As

Publication number Publication date
DE1230170B (de) 1966-12-08
GB969865A (no) 1964-09-16

Similar Documents

Publication Publication Date Title
US3174817A (en) Chrome-acetate complex tannage
US4919680A (en) High-extraction chrome tanning process
US3811832A (en) Tanning improvements
US3909193A (en) Tanning formulations
US7063728B2 (en) Process for making chrome tanned leathers
US3960481A (en) Process for tanning leather
US3938951A (en) Method of obtaining titanium tanning agent and its application for tanning hides, pelts and fur skins
US2264414A (en) Tanning with complex basic zirconium sulphates
GB1363342A (en) Pulverulent mixture for tanning animal hides and leather
US2639967A (en) Deliming hides with citric acid fermentation liquor
US4938779A (en) Chrome tanning of leather with reduced waste of chromium
US725648A (en) Process of tanning hides, skins, or other animal tissues.
US4211529A (en) Chrome-tanning
US4327997A (en) Chrome utilization in chrome tanning
US4049379A (en) Complex basic zirconium salts and aluminum salts
US2826477A (en) Process of tanning skins with acidic solutions of alkali metal zirconium silicates
US1941285A (en) Titanium sulphate compounds
US3690812A (en) Process for chromium tanning and bath for carrying out said process
US2512708A (en) Resorcinol-aldehyde tanning product
US1940610A (en) Method of mineral tanning
US2707667A (en) Tanning limed skins
US3097912A (en) Hair and wool depilation method and composition
US2004473A (en) Production of leather
US3493318A (en) Tanning composition made from a basic chrome sulfate and a tris(hydroxyacetato)chromiate
US4314803A (en) Tanning method