US2141276A - Tanning agents and process of producing the same - Google Patents
Tanning agents and process of producing the same Download PDFInfo
- Publication number
- US2141276A US2141276A US85908A US8590836A US2141276A US 2141276 A US2141276 A US 2141276A US 85908 A US85908 A US 85908A US 8590836 A US8590836 A US 8590836A US 2141276 A US2141276 A US 2141276A
- Authority
- US
- United States
- Prior art keywords
- tanning
- parts
- soluble
- agents
- degradation
- 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
Links
- 238000000034 method Methods 0.000 title description 10
- 239000003795 chemical substances by application Substances 0.000 description 28
- 239000007857 degradation product Substances 0.000 description 15
- 239000000126 substance Substances 0.000 description 15
- 150000001875 compounds Chemical class 0.000 description 14
- 239000002253 acid Substances 0.000 description 13
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 12
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- 150000002506 iron compounds Chemical class 0.000 description 10
- 230000001590 oxidative effect Effects 0.000 description 10
- 230000015556 catabolic process Effects 0.000 description 9
- 239000010985 leather Substances 0.000 description 9
- 238000006731 degradation reaction Methods 0.000 description 8
- 238000001704 evaporation Methods 0.000 description 8
- 159000000014 iron salts Chemical class 0.000 description 7
- 239000002244 precipitate Substances 0.000 description 7
- 239000000047 product Substances 0.000 description 7
- 229910052742 iron Inorganic materials 0.000 description 6
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 description 6
- 230000002797 proteolythic effect Effects 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 4
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 239000012736 aqueous medium Substances 0.000 description 4
- 230000008020 evaporation Effects 0.000 description 4
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 4
- 229910017604 nitric acid Inorganic materials 0.000 description 4
- 235000011121 sodium hydroxide Nutrition 0.000 description 4
- 239000001117 sulphuric acid Substances 0.000 description 4
- 235000011149 sulphuric acid Nutrition 0.000 description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 230000000593 degrading effect Effects 0.000 description 3
- 239000003292 glue Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- 238000007790 scraping Methods 0.000 description 3
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 235000013379 molasses Nutrition 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000007800 oxidant agent Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- WBHQBSYUUJJSRZ-UHFFFAOYSA-M sodium bisulfate Chemical compound [Na+].OS([O-])(=O)=O WBHQBSYUUJJSRZ-UHFFFAOYSA-M 0.000 description 2
- YPFNIPKMNMDDDB-UHFFFAOYSA-K 2-[2-[bis(carboxylatomethyl)amino]ethyl-(2-hydroxyethyl)amino]acetate;iron(3+) Chemical compound [Fe+3].OCCN(CC([O-])=O)CCN(CC([O-])=O)CC([O-])=O YPFNIPKMNMDDDB-UHFFFAOYSA-K 0.000 description 1
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 description 1
- 235000010469 Glycine max Nutrition 0.000 description 1
- 244000068988 Glycine max Species 0.000 description 1
- CZMRCDWAGMRECN-UGDNZRGBSA-N Sucrose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO)O1 CZMRCDWAGMRECN-UGDNZRGBSA-N 0.000 description 1
- 229930006000 Sucrose Natural products 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- 244000309466 calf Species 0.000 description 1
- 239000005018 casein Substances 0.000 description 1
- BECPQYXYKAMYBN-UHFFFAOYSA-N casein, tech. Chemical compound NCCCCC(C(O)=O)N=C(O)C(CC(O)=O)N=C(O)C(CCC(O)=N)N=C(O)C(CC(C)C)N=C(O)C(CCC(O)=O)N=C(O)C(CC(O)=O)N=C(O)C(CCC(O)=O)N=C(O)C(C(C)O)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=O)N=C(O)C(CCC(O)=O)N=C(O)C(COP(O)(O)=O)N=C(O)C(CCC(O)=N)N=C(O)C(N)CC1=CC=CC=C1 BECPQYXYKAMYBN-UHFFFAOYSA-N 0.000 description 1
- 235000021240 caseins Nutrition 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- GPRLSGONYQIRFK-UHFFFAOYSA-N hydron Chemical compound [H+] GPRLSGONYQIRFK-UHFFFAOYSA-N 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- ZJZXSOKJEJFHCP-UHFFFAOYSA-M lithium;thiocyanate Chemical compound [Li+].[S-]C#N ZJZXSOKJEJFHCP-UHFFFAOYSA-M 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- GQPLMRYTRLFLPF-UHFFFAOYSA-N nitrous oxide Inorganic materials [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 235000018102 proteins Nutrition 0.000 description 1
- 102000004169 proteins and genes Human genes 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 229960004793 sucrose Drugs 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- 235000013311 vegetables Nutrition 0.000 description 1
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
-
- 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
-
- 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
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S530/00—Chemistry: natural resins or derivatives; peptides or proteins; lignins or reaction products thereof
- Y10S530/827—Proteins from mammals or birds
- Y10S530/842—Skin; hair; nails; sebaceous glands; cerumen
-
- 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
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S530/00—Chemistry: natural resins or derivatives; peptides or proteins; lignins or reaction products thereof
- Y10S530/859—Waste, waste material, refuse or sludge, e.g. effluents, fecal matter
Definitions
- the present invention relates to new tanning agents and a process of producing the same.
- tanning agents containing iron obtained by treating albuminous substances with oxidizing agents (for example nitric acid, oxides of nitrogen or oxidizing substances free from nitrogen) in the presence of iron salts have certain drawbacks; they are un-' stable, difficult to obtain in a concentrated form 10 and diflicult to handle.
- oxidizing agents for example nitric acid, oxides of nitrogen or oxidizing substances free from nitrogen
- tanning agents containing iron free fromthe said drawbacks can be obtained by combining iron compounds, in particular iron salts, with soluble al- 5 buminous substances including soluble proteinic substances and soluble degradation products thereof which in case of oxidizing degradation have been made in the absence of iron.
- iron compounds in particular iron salts
- soluble al- 5 buminous substances including soluble proteinic substances and soluble degradation products thereof which in case of oxidizing degradation have been made in the absence of iron.
- albuminous substances or their derivatives or degradation products thereof obtainable with the aid of non-oxidizing proteolytic agents are employed, the tanning composition may be prepared by mixing the albuminous substances with iron compounds and, if desired, heating the mixture. The process may be carried out for example by mixing albumen in the presence of iron salts with non-oxidizing proteolytic agents and, if desired, heating.
- albumen especially in the case of insoluble albumens, may be. first subjected to any desired proteolytic treatment, as for example with acid,
- salts having a splitting action as for example calcium chloride or lithium thiocyanate.v
- Sulphonic acids, especially sulphonic acids having tanning action may be mentioned for example as agents suitable for carrying out the splitting.
- the splitting may be carried out under increased pressure.
- the albumen may also be converted into. water-soluble products by the action of ethylene oxide or the like.
- the resulting albumen degradation products or derivatives may then be mixed with the iron salts in order to obtain the tanning composition.
- the tanning material may also be obtained by combining degradation products of albuminous substances or their derivatives, which have i been obtained in the absence of iron compounds with the aid of oxidizing agents, as for example nitric acid, nitrous gases or hydrogen peroxide, 'with iron compounds having a tanning action.
- oxidizing agents as for example nitric acid, nitrous gases or hydrogen peroxide
- the addition of the ironcompounds should be effected after the oxidation while in other cases the iron compounds may be added to the albuminous substances or 60 degradation products thereof before,-. during or alkaline or enzymatic-splitting agents or neutral after degradation, if any degradation is effected at all.
- a preliminary tanning may also be carof the iron salts.
- the tanning agent containing iron compounds and albuminous substances contains free acid (for example from the degradation step) it is advantageous to neutralize the acid at least to a far-going degree; the solution may then be evaporated in the usual manner under ordinary or diminished pressure.
- - Acid reacting agents may then be added to the dry products. hygroscopic pulverulent products are thus obtained. Suitable acid reacting agents are for example oxalic acid and alkali metal bisulphates. The products are readily soluble in water and may be directly employed for tanning afterbeing adjusted to the usual acidity and hydrogen ion concentration.
- Suitable abluminous substances are for example leather scraps for making glue, leather parings, casein, horn and the like and also their soluble degradation products and derivatives;
- iron compounds may be mentioned all iron compounds having tanning action, in particular the water soluble ferric salts.
- the tanning with the aid of the tanning agents above described may be combined in any desired manner with other tanning methods; for example leather tanned with the said tanning agents may be further treated with mineral, synthetic organic or vegetable tanning agents or their neutral salts, or the reverse procedure may be fol-' lowed.
- the said tanning agents have an excellent tanning action which in part is superior to that of the known irontanning agents. Their stability as well as their capacity for being stored and transported is usually very good. Leather prepared with the aid of the said tanning agents shows no plumping when washed.
- Example 1 30 parts of leather scraps for making glue are evaporated to dryness and mixed with 4 parts' of anhydrous ferric chloride. A good iron tanning agent is thus obtained.
- Example 2 500 parts of soy bean cuttings are boiled with 2000 parts of 25 percent sulphuric acid for 16 hours, the sulphuric acid then being precipitated as barium sulphate and filtered off. The filtrate is evaporated, about 180 parts of albumen degradation products being obtained as the residue. This is mixed with 360 parts of anhydrous ferric chloride, an excellent iron tan-' ning agent thus being obtained.
- Example 3 50 parts of cane sugar molasses, which contains albumen degradation products, are mixed with 35 parts of ferric nitrate, an excellent tanning agent being obtained. Other molasses containing albumen, or similar products, may be used in a similar manner. 1
- Example 4 Pickled unhaired calf pelts are drummed for 6 hours in a bath consisting of 100 per cent of water, 17 per cent of ferric nitrate and 4.5 per cent of calcined sodium carbonate, the percentages being with reference to the weight of unhaired pelts. The tanning is then carried out, 0.5 per cent of protalbic acid being added periodically in small amounts.
- Example 5 100 parts of leather scraps for making glue are heated for three hours at 90 C. with 50 parts of nitric acid having a specific gravity of 1.333 and 40 parts of water. After cooling, the whole is neutralized with caustic soda solution and evaporated. The residue is mixed with parts of ferric nitrate. a good iron tanning agent.
- Example 6 700 parts of chrome leather scrapings containing 65 per cent of water are treated for two hours at 100 C. with 150 parts of sulphuric acid of 66 Baum strength. The mass is then neutralized with 117 parts of caustic soda and 368 parts of anhydrous ferric chloride are added. The viscous mass obtained possesses an excellent tanning action.
- Example 8 100 parts of dry chrome leather scrapings are treated for three hours at C. with 800 parts of 20 per cent sulphuric acid and 162 parts of anhydrous ferric sulphate. The reaction prodnot is neutralized with 635 parts of a 35 per cent The resulting product is sodium hydroxide solution and evaporated to dryness. Each parts of the powder obtained are mixed with 50 parts of sodium bisulphate.
- Example 9 5 parts of dry chrome leather scrapings are treated for three hours at 85 C. with 10 parts of an about 53 per cent nitric acid, 8.4 parts of crystallized ferric chloride and 20.4 parts of water then being added. The mass is neutralized with 3.52 parts of a 35 per cent caustic soda solution and evaporated to dryness. Each 100 parts of the dry product obtained are mixed with 50 parts of sodium bisulphate.
- tanning compounds which comprises degrading an albuminous substance in an aqueous medium, evaporating the solution obtained to dryness and then combining the degradation product with a soluble ferric compound which does not form a precipitate therewith.
- tanning compounds which comprises degrading an albuminous substance in an aqueous medium with an oxidizing proteolytic agent, evaporating the solution obtained to dryness and then combining the degradation product with a soluble ferric compound which does not form a precipitate therewith.
- tanning compounds which comprises degrading an albuminous substance in an aqueous medium with a non-oxidizing proteolytic agent, evaporating the solution obtained to dryness and then combining the degradation product with a soluble ferric compound which does not form a precipitate therewith.
- tanning compounds which comprises combining a soluble ferric compound with a soluble albuminous substance which latter is obtained by degradation of a protein by an acid agent, neutralizing the acid agent at least partly, evaporating the mass and adding an acid reacting agent.
- Tanning materials comprising a soluble albuminous degradation compound obtained by awet process, excluding oxidation, and by evaporation to dryness, and a soluble ferric compound which does not form a precipitate therewith.
- Tanning materials comprising a soluble albuminous degradation product obtained by means of a non-oxidizing proteolytic agent in an aqueous medium and evaporation to dryness, and a soluble ferric compound which does not form a precipitate therewith.
- Tanning materials comprising a soluble albuminous degradation product obtained by wet oxidizing degradation and evaporation to dryness, and a soluble ferric compound added after evaporation and which does not form a precipitate with the said degradation product.
- Non-hydroscopic tanning materials comprising (1) a soluble ferric compound, (2) a neutralized soluble acid albuminous degradation product which is obtained while avoiding an oxidizing breakdown in the presence of an iron compound and does not form a precipitate with the said ferric compound, and (3) an acid reacting agent.
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)
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2141276X | 1935-06-26 | ||
| DE416251X | 1935-06-26 | ||
| DEI52640D DE669566C (de) | 1935-06-26 | 1935-06-27 | Verfahren zur Herstellung eisenhaltiger Gerbmittel |
| DEI52641D DE670537C (de) | 1935-06-26 | 1935-06-27 | Verfahren zur Herstellung eisenhaltiger Gerbmittel |
| GB23825/35A GB462026A (en) | 1935-06-26 | 1935-08-26 | Improvements in the manufacture and production of tanning agents containing iron |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2141276A true US2141276A (en) | 1938-12-27 |
Family
ID=60571006
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US85908A Expired - Lifetime US2141276A (en) | 1935-06-26 | 1936-06-18 | Tanning agents and process of producing the same |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US2141276A (fr) |
| BE (1) | BE416251A (fr) |
| DE (2) | DE670537C (fr) |
| GB (1) | GB462026A (fr) |
-
1935
- 1935-06-27 DE DEI52641D patent/DE670537C/de not_active Expired
- 1935-06-27 DE DEI52640D patent/DE669566C/de not_active Expired
- 1935-08-26 GB GB23825/35A patent/GB462026A/en not_active Expired
-
1936
- 1936-06-18 US US85908A patent/US2141276A/en not_active Expired - Lifetime
- 1936-06-25 BE BE416251D patent/BE416251A/fr unknown
Also Published As
| Publication number | Publication date |
|---|---|
| DE670537C (de) | 1939-01-20 |
| GB462026A (en) | 1937-02-26 |
| BE416251A (fr) | 1936-07-31 |
| DE669566C (de) | 1938-12-29 |
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