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US3973904A Expired / Lapsed US ⏱️ 0.0 years remaining

Water-soluble synthetic tanning agents

Assignee: BASF SE
•
Filing: 1972-03-10
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Granted: 1976-08-10
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Expires: 1992-03-10
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Abstract

Abstract Water-soluble synthetic tanning agents composed of formaldehyde condensation products of non-sulfonated aromatic hydroxy compounds or the sulfomethylation products thereof with aromatic sulfonic acids or with the formaldehyde condensation products of said sulfonic acids.

Inventors

  • 👤 Horst Endres
  • 👤 Otto Hertel
  • 👤 Franz-Friedrich Miller

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 15:24
CPC Classifications
C; C14; C14C; C14C3/00; C14C3/02; C14C3/08; C14C3/18; C14C3/20

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 119 words
Synthetic water-soluble tanning agents substantially comprising a mixture of: a. from 25 to 75% by weight -- with reference to the weight of (a) + (b) -- of condensation products based on formaldehyde and mono- or dinuclear aromatic hydroxy compounds free from aromatically bonded sulfonic acid groups, or the sulfomethylated condensation products thereof or mixtures of said aromatic hydroxy compounds and said sulfomethylated condensation products, and b. from 75 to 25% by weight of aromatic or hydroxyaromatic sulfonic acids or their condensation products with formaldehyde or their condensation products with formaldehyde and urea, or a mixture of said compounds, at least a portion of said sulfonic acids being in the form of alkali metal salts, ammonium salts or both.
Claim 2
Dependent Claim 119 words
Synthetic water-soluble tanning agents substantially comprising a mixture of: a. from 25 to 75% by weight -- with reference to the weight of (a) + (b) -- of condensation products based on formaldehyde and mono- or dinuclear aromatic hydroxy compounds free from aromatically bonded sulfonic acid groups, or the sulfomethylated condensation products thereof or mixtures of said aromatic hydroxy compounds and said sulfomethylated condensation products, and b. from 75 to 25% by weight of aromatic or hydroxyaromatic sulfonic acids or their condensation products with formaldehyde or their condensation products with formaldehyde and urea, or a mixture of said compounds, at least a portion of said sulfonic acids being in the form of alkali metal salts, ammonium salts or both.
Claim 3
Dependent Claim 80 words
Tanning agents as claimed in claim 1, wherein the component (a) includes as mono- or dinuclear aromatic hydroxy compound one or more compounds selected from the group consisting of phenol, naphthol, resorcinol, pyrocatechol, dioxydiphenylpropane, dihydroxydiphenylsulfone, the sulfomethylation products of the foregoing, halophenols and xylenols, and wherein the component (b) is based on a compound selected from the group consisting of benzenesulfonic acid, naphthalenesulfonic acid, phenolsulfonic acid and the condensation products of the foregoing with formaldehyde or with formaldehyde and urea.
Claim 4
Dependent Claim 33 words
Tanning agents as claimed in claim 1, wherein the component (a) is based on sulfomethylation products and the component (b) is based on condensation products of aromatic sulfonic acids with urea and formaldehyde.
Claim 5
Dependent Claim 34 words
Tanning agents as claimed in claim 1, wherein the component (b) is a condensation product of naphthalenesulfonic acid or naphtholsulfonic with urea and formaldehyde in the form of its alkali metal or ammonium salt.

References Cited (Backward Citations)

CA870503A Cited
US2829122A Cited
DE1142173B Cited
DE1178081B Cited
US3512918A Cited
US3423452A Cited
US3477801A Cited
DE1935006A1 Cited
US3617186A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-08-10 1980-02-09 1980-08-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-08-10 1984-02-09 1984-08-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-08-10 1988-02-09 1988-08-10 $7700.00 Window Closed / Lapsed

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