US2091683A - Chrome tanning - Google Patents
Chrome tanning Download PDFInfo
- Publication number
- US2091683A US2091683A US57363A US5736336A US2091683A US 2091683 A US2091683 A US 2091683A US 57363 A US57363 A US 57363A US 5736336 A US5736336 A US 5736336A US 2091683 A US2091683 A US 2091683A
- Authority
- US
- United States
- Prior art keywords
- tanning
- hides
- chromium
- leather
- acid
- 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
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 title description 6
- 150000001844 chromium Chemical class 0.000 description 23
- 239000010985 leather Substances 0.000 description 16
- 238000000034 method Methods 0.000 description 15
- XNGIFLGASWRNHJ-UHFFFAOYSA-N phthalic acid Chemical compound OC(=O)C1=CC=CC=C1C(O)=O XNGIFLGASWRNHJ-UHFFFAOYSA-N 0.000 description 12
- 239000003795 chemical substances by application Substances 0.000 description 11
- WPYMKLBDIGXBTP-UHFFFAOYSA-N benzoic acid Chemical compound OC(=O)C1=CC=CC=C1 WPYMKLBDIGXBTP-UHFFFAOYSA-N 0.000 description 8
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000002253 acid Substances 0.000 description 5
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 4
- 159000000032 aromatic acids Chemical class 0.000 description 4
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-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
- LGRFSURHDFAFJT-UHFFFAOYSA-N Phthalic anhydride Natural products C1=CC=C2C(=O)OC(=O)C2=C1 LGRFSURHDFAFJT-UHFFFAOYSA-N 0.000 description 3
- 150000007513 acids Chemical class 0.000 description 3
- -1 alkali metal salts Chemical class 0.000 description 3
- 150000001555 benzenes Chemical class 0.000 description 3
- 239000011651 chromium Substances 0.000 description 3
- 239000011696 chromium(III) sulphate Substances 0.000 description 3
- 235000015217 chromium(III) sulphate Nutrition 0.000 description 3
- 230000007935 neutral effect Effects 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 241001494479 Pecora Species 0.000 description 2
- 229940037003 alum Drugs 0.000 description 2
- JHIWVOJDXOSYLW-UHFFFAOYSA-N butyl 2,2-difluorocyclopropane-1-carboxylate Chemical compound CCCCOC(=O)C1CC1(F)F JHIWVOJDXOSYLW-UHFFFAOYSA-N 0.000 description 2
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 238000006386 neutralization reaction Methods 0.000 description 2
- 238000011282 treatment Methods 0.000 description 2
- WZHHYIOUKQNLQM-UHFFFAOYSA-N 3,4,5,6-tetrachlorophthalic acid Chemical compound OC(=O)C1=C(Cl)C(Cl)=C(Cl)C(Cl)=C1C(O)=O WZHHYIOUKQNLQM-UHFFFAOYSA-N 0.000 description 1
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- 241000920033 Eugenes Species 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- 125000001931 aliphatic group Chemical group 0.000 description 1
- RGCKGOZRHPZPFP-UHFFFAOYSA-N alizarin Chemical compound C1=CC=C2C(=O)C3=C(O)C(O)=CC=C3C(=O)C2=C1 RGCKGOZRHPZPFP-UHFFFAOYSA-N 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 229940053200 antiepileptics fatty acid derivative Drugs 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 244000309466 calf Species 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 239000007859 condensation product Substances 0.000 description 1
- 238000004043 dyeing Methods 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- KYTZHLUVELPASH-UHFFFAOYSA-N naphthalene-1,2-dicarboxylic acid Chemical class C1=CC=CC2=C(C(O)=O)C(C(=O)O)=CC=C21 KYTZHLUVELPASH-UHFFFAOYSA-N 0.000 description 1
- YZMHQCWXYHARLS-UHFFFAOYSA-N naphthalene-1,2-disulfonic acid Chemical class C1=CC=CC2=C(S(O)(=O)=O)C(S(=O)(=O)O)=CC=C21 YZMHQCWXYHARLS-UHFFFAOYSA-N 0.000 description 1
- PSZYNBSKGUBXEH-UHFFFAOYSA-N naphthalene-1-sulfonic acid Chemical compound C1=CC=C2C(S(=O)(=O)O)=CC=CC2=C1 PSZYNBSKGUBXEH-UHFFFAOYSA-N 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 150000003022 phthalic acids Chemical class 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 150000007519 polyprotic acids Polymers 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 238000006467 substitution reaction Methods 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
- 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
Definitions
- the present invention relates to improvements in chrome tanning by treating hides withtanning agents comprising chromium salts of nontanning polybasic aromatic acids, as well as to the said tannings employed and the leather obtained therewith.
- chrome tanning by the single bath process, chromium salts of inorganic acids or of aliphatic acids, such as formic acid or oxalic acid, have hitherto been used.
- chromium salts of inorganic acids or of aliphatic acids such as formic acid or oxalic acid
- fatty acid derivatives Teurkey red oils
- the chrome tanning has also been carried out in conjunction with vegetable or synthetic tanning agents.
- Suitable acids are for example phthalic acids, naphthalene-dicarboxylic acids, and naphthalene disulphonic acids and certain substitution products thereof.
- the chromium salts of these acids may be obtained, depending on the nature of the polybasic acid used, for example by the reaction of their alkali metal salts with neutral or basic chromium sulphate.
- the procedure may also be that the hides are pretreated with one component and then treated with the other component, the treatments being repeated if desired.
- chromium oxide calculated with reference to the finished leather
- aromatic acid may be read- 40 ily incorporated with the hides.
- an increase in weight and volume of the leather of per cent and more can be obtained so that full leather with the character of a combination tanning can be obtained in a simple manner.
- Pickling, neutralization at the conclusion of the tanning or deacidification of the hides, as for example before dyeing, may be dispensed with when the basicity of the bath is suitable, in particular when 50 employing chromium salts of weak aromatic acids.
- the said chromium salts can also be employed together or in any desired sequence with other tanning agents.
- Example 1 222 parts of phthalic anhydride are dissolved in water with the addition of 120 parts of sodium hydroxide and the solution rendered neutral to litmus. From 450 to 500 parts 01' chromium alum are then added to the solution. Into the resulting solution (80 per cent of the weight of the unhaired hides) there are introduced delimed unhaired sheep hides, and the latter are treated in the usual manner according to the single bath tanning process. In order to obtain ripe tanning, a little soda may be added to the tanning liquor towards the end of the tanning if desired.
- Emmple 2 148 parts of phthalic anhydride are dissolved in water with an addition of 80 parts of sodium hydroxide and the solution is rendered neutral to litmus. A solution of basic chromium sulphate (Cr(OH)SO4) corresponding to 76 parts of CrzOs is then added.
- Cr(OH)SO4 basic chromium sulphate
- Delimed non-pickled unhaired hides are treated with the resulting tanning liquor in a short bath (45 per cent of the weight or the unhaired hides). 4
- a ripe-tanned leather is obtained without any neutralization of the tanning liquor with soda being necessary.
- Example 3 Delimed and bated unhaired calf hides are fully tanned in a short bath per cent of the weight of the unhaired hides) with a solution of 276 parts or i-nitronaphthalene-3.8-disulphonic acid sodium salt and a solution'of basic chromium sulphate (Cr(OI-I)SO4) corresponding to 76 parts of CrzOa.
- Example 5 1000 parts of dry East-Indian sheep leather are thoroughly wetted with warm water, if desired with an addition of 5 parts of calcined sodium carbonate and treated in the same manner as described in Example 4.
- Example 6 1000 parts of alum ripe leather are wetted and after-tanned in the manner described in Examples 4 and 5.
- the process of tanning which comprises treating hides with a chromium salt of a nontanning polybasic aromatic carboxylic acid.
- the process of tanning which comprises treating hides with a chromium salt of a nontanning polybasic aromatic carboxylic acid and with a further tanning agent.
- the process of tanning which comprises treating hides pretanned by means of known tanning agents with a chromium salt of a nontanning polybasic aromatic carboxylic acid.
- the process of tanning which comprises first treating hides with a chromium salt of a nontanning polybasic aromatic carboxylic acid and then treating them with a known tanning agent.
- the process of tanning which comprises first treating hides with a tanning chromium salt and then with a non-tanning polybasic aromatic carboxylic acid compound.
- the process of tanning which comprises first treating hides with a tanning chromium salt and then with a non-tanning polybasic aromatic carboxylic acid salt.
- the process of tanning which comprises repeatedly first treating hides with a tanning chromium salt and then with a non-tanning polybasic aromatic carboxylic acid compound.
- Chrome-tanning agents comprising a chromium salt of a non-esterified non-tanning polybasic aromatic carboxylic acid.
- Chrome-tanning agents comprising a chromium salt of a non-esterified non-tanning polybasic carboxylic acid of the benzene series.
- Chrome-tanning agents comprising a chromium salt of non-esterified phthalic acid.
- Chrometanning agents comprising a chr0- mium salt of non-esterified tetrachloro phthalic acid.
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)
Description
Patented Aug. 31, 1937 UNITED STATES PATENT OFFICE Rhine, Germany,
dustrie Aktiengesellschatt,
Main, Germany No Drawing. Application January 3, No. 57,363. In Germany January 18 Claims.
The present invention relates to improvements in chrome tanning by treating hides withtanning agents comprising chromium salts of nontanning polybasic aromatic acids, as well as to the said tannings employed and the leather obtained therewith.
For chrome tanning by the single bath process, chromium salts of inorganic acids or of aliphatic acids, such as formic acid or oxalic acid, have hitherto been used. The addition of fatty acid derivatives (Turkey red oils) during the tanning has also been proposed. In order to obtain leather having certain desired properties, the chrome tanning has also been carried out in conjunction with vegetable or synthetic tanning agents.
I have now found that very good and especially full leather can be obtained by treating hides with chromium salts of non-tanning poly- 20 basic aromatic acids in the known manner, The
term polybasic aromatic acids, whenever used,
includes polybasic aromatic carboxylic and sulphonic acids. Suitable acids are for example phthalic acids, naphthalene-dicarboxylic acids, and naphthalene disulphonic acids and certain substitution products thereof. The chromium salts of these acids may be obtained, depending on the nature of the polybasic acid used, for example by the reaction of their alkali metal salts with neutral or basic chromium sulphate.
In many cases the procedure may also be that the hides are pretreated with one component and then treated with the other component, the treatments being repeated if desired.
35 The tanning proceeds simply and rapidly.
When desired, as much as per cent of chromium oxide (calculated with reference to the finished leather) in combination with the corresponding amount of aromatic acid may be read- 40 ily incorporated with the hides. Thus for example by tanning in short baths an increase in weight and volume of the leather of per cent and more can be obtained so that full leather with the character of a combination tanning can be obtained in a simple manner. Pickling, neutralization at the conclusion of the tanning or deacidification of the hides, as for example before dyeing, may be dispensed with when the basicity of the bath is suitable, in particular when 50 employing chromium salts of weak aromatic acids.
In order to obtain leather having special properties the said chromium salts can also be employed together or in any desired sequence with other tanning agents. Thus hides which had assignor to I. G.
Farbenln- Franktort-on-the- 1930, Serial 19, 1935 Example 1 222 parts of phthalic anhydride are dissolved in water with the addition of 120 parts of sodium hydroxide and the solution rendered neutral to litmus. From 450 to 500 parts 01' chromium alum are then added to the solution. Into the resulting solution (80 per cent of the weight of the unhaired hides) there are introduced delimed unhaired sheep hides, and the latter are treated in the usual manner according to the single bath tanning process. In order to obtain ripe tanning, a little soda may be added to the tanning liquor towards the end of the tanning if desired.
Emmple 2 148 parts of phthalic anhydride are dissolved in water with an addition of 80 parts of sodium hydroxide and the solution is rendered neutral to litmus. A solution of basic chromium sulphate (Cr(OH)SO4) corresponding to 76 parts of CrzOs is then added.
Delimed non-pickled unhaired hides are treated with the resulting tanning liquor in a short bath (45 per cent of the weight or the unhaired hides). 4
A ripe-tanned leather is obtained without any neutralization of the tanning liquor with soda being necessary.
Example 3 Delimed and bated unhaired calf hides are fully tanned in a short bath per cent of the weight of the unhaired hides) with a solution of 276 parts or i-nitronaphthalene-3.8-disulphonic acid sodium salt and a solution'of basic chromium sulphate (Cr(OI-I)SO4) corresponding to 76 parts of CrzOa.
Example! 1200 parts 01' shaved non-deacidifled chrome leather, which had been prepared according to the chrome-singleor -two-bath-process in the usual manner are treated with the tanning liquor described in Example 2 horsed up overnight,
5 washed, dyed by any of the standard methods, fat-liquored and finished as usual. In order to obtain leather of an especially high fullness a treatment with synthetic tanning agents, as for example with condensation products of naphthalene sulphonic acid and formaldehyde can be inserted at any desired stage of the tanning process. Instead of the tan prepared from phthalic acid anhydride described above there can also be employed the corresponding amount of a similar \5 tan but prepared from tetrachlor phthalic acid.
Example 5 1000 parts of dry East-Indian sheep leather are thoroughly wetted with warm water, if desired with an addition of 5 parts of calcined sodium carbonate and treated in the same manner as described in Example 4.
Example 6 1000 parts of alum ripe leather are wetted and after-tanned in the manner described in Examples 4 and 5.
What I claim is:
1. The process of tanning which comprises treating hides with a chromium salt of a nontanning polybasic aromatic carboxylic acid.
2. The process of tanning which comprises treating hides with a chromium salt of a nontanning polybasic aromatic carboxylic acid and with a further tanning agent.
3. The process of tanning which comprises treating hides pretanned by means of known tanning agents with a chromium salt of a nontanning polybasic aromatic carboxylic acid.
4. The process of tanning which comprises first treating hides with a chromium salt of a nontanning polybasic aromatic carboxylic acid and then treating them with a known tanning agent.
5. The process of tanning which comprises treating hides with a chromium salt of a nontanning po-lybasiccarboxylic acid of the benzene series.
6. The process of tanning which comprises treating hides with a chromium salt of phthalic acid.
7. The process of tanning which comprises treating hides with a chromium salt of tetrachlor phthalic acid.
8. The process of tanning which comprises first treating hides with a tanning chromium salt and then with a non-tanning polybasic aromatic carboxylic acid compound.
9. The process of tanning which comprises first treating hides with a tanning chromium salt and then with a non-tanning polybasic aromatic carboxylic acid salt.
10. The process of tanning which comprises repeatedly first treating hides with a tanning chromium salt and then with a non-tanning polybasic aromatic carboxylic acid compound.
11. Leather containing a chromium salt of a non-tanning polybasic aromatic carboxylic acid.
12. Leather containing a chromium salt of a non-tanning polybasic carboxylic acid of the benzene series.
13. Leather containing a chromium salt of phthalic acid.
14. Leather containing a chromium salt oi! tetrachlor phthalic acid.
15. Chrome-tanning agents comprising a chromium salt of a non-esterified non-tanning polybasic aromatic carboxylic acid.
16. Chrome-tanning agents comprising a chromium salt of a non-esterified non-tanning polybasic carboxylic acid of the benzene series.
17. Chrome-tanning agents comprising a chromium salt of non-esterified phthalic acid.
18. Chrometanning agents comprising a chr0- mium salt of non-esterified tetrachloro phthalic acid.
EUGEN IMMENDOERFER.
Applications Claiming Priority (8)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE412752X | 1935-01-19 | ||
| DE451087X | 1935-01-19 | ||
| DE799017X | 1935-01-19 | ||
| DE2091683X | 1935-01-19 | ||
| DEI51489D DE643088C (en) | 1935-01-19 | 1935-01-20 | Process for chrome tanning |
| DE418658X | 1935-12-13 | ||
| DEI53874D DE653791C (en) | 1935-01-19 | 1935-12-14 | Process for chrome tanning |
| FR47843T | 1936-11-26 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2091683A true US2091683A (en) | 1937-08-31 |
Family
ID=60387780
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US57363A Expired - Lifetime US2091683A (en) | 1935-01-19 | 1936-01-03 | Chrome tanning |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US2091683A (en) |
| BE (2) | BE412752A (en) |
| DE (2) | DE643088C (en) |
| FR (2) | FR799017A (en) |
| GB (1) | GB451087A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2544667A (en) * | 1946-04-27 | 1951-03-13 | Du Pont | Werner-type chromium compounds as laminating and coating compositions |
| US2829943A (en) * | 1956-01-24 | 1958-04-08 | Edward M Filachione | Tanning agent and process |
| US4042321A (en) * | 1974-05-18 | 1977-08-16 | Bayer Aktiengesellschaft | Tanning of hides |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1494825C3 (en) * | 1966-10-27 | 1970-12-03 | Basf Ag | Process for the immediate tanning of limed bare |
| DE2424300C3 (en) * | 1974-05-18 | 1984-11-08 | Bayer Ag, 5090 Leverkusen | Process for chrome tanning and tanning mix therefor |
-
1935
- 1935-01-20 DE DEI51489D patent/DE643088C/en not_active Expired
- 1935-12-11 FR FR799017D patent/FR799017A/en not_active Expired
- 1935-12-12 BE BE412752D patent/BE412752A/en unknown
- 1935-12-14 DE DEI53874D patent/DE653791C/en not_active Expired
-
1936
- 1936-01-03 US US57363A patent/US2091683A/en not_active Expired - Lifetime
- 1936-01-17 GB GB1591/36A patent/GB451087A/en not_active Expired
- 1936-11-23 BE BE418658D patent/BE418658A/en unknown
- 1936-11-26 FR FR47843D patent/FR47843E/en not_active Expired
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2544667A (en) * | 1946-04-27 | 1951-03-13 | Du Pont | Werner-type chromium compounds as laminating and coating compositions |
| US2829943A (en) * | 1956-01-24 | 1958-04-08 | Edward M Filachione | Tanning agent and process |
| US4042321A (en) * | 1974-05-18 | 1977-08-16 | Bayer Aktiengesellschaft | Tanning of hides |
Also Published As
| Publication number | Publication date |
|---|---|
| BE412752A (en) | 1936-01-31 |
| FR47843E (en) | 1937-07-31 |
| GB451087A (en) | 1936-07-29 |
| BE418658A (en) | 1936-12-31 |
| DE643088C (en) | 1937-03-24 |
| FR799017A (en) | 1936-05-30 |
| DE653791C (en) | 1937-12-02 |
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