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US4035213A Expired / Lapsed US ⏱️ 0.0 years remaining

Soft textile coatings resembling napa leather

Assignee: Bayer AG
•
Filing: 1975-12-03
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Granted: 1977-07-12
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Expires: 1995-12-03
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Abstract

Abstract This invention relates to the coating of textile sheets with polyurethane pastes by the reversal process for producing very soft coating articles with a hand resembling that of napa leather. The particular properties of the coating are obtained by using bonding pastes which contain a mixture which can be cross-linked by the action of heat, consisting of polyurethane hydrazodicarbonamides and melamine-formaldehyde resins and/or urea-formaldehyde resins.

Inventors

  • 👤 Wilhelm Thoma
  • 👤 Josef Pedain
  • 👤 Jurgen Grammel
  • 👤 Antonio Aguado

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 22:49
CPC Classifications
D; D06; D06N; D06N3/00; D06N3/12; D06N3/14; D06N3/147; D06N3/148; C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/10; C09; C09D; C09D175/00; C09D175/04; D06N3/142; D06N3/143; Y; Y10; Y10S; Y10S428/00; Y10S428/904; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551; Y10T428/31554; Y10T428/31594

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 190 words
Process for the production of textile coatings which have an exceptionally soft hand resembling that of napa leather by applying a polurethane paste which contains melamine formaldehyde resins and/or urea-formaldehyde resins as a bonding coat and another polyurethane paste as top coat to textile supports in the form of webs by the reversal process followed by evaporation of the solvent or dispersing agent and simultaneous acid catalysed cross-linking of the components of the bonding coat, characterised in that the bonding coats used are pastes with a solids content of from 30 to 70%, by weight, consisting of: 100 parts, by weight, of a polyurethane from (1) a prepolymer from (a) dihydroxy polyesters or dihydroxy polyethers; and (b) aliphatic and/or cycloaliphatic diisocyanates with a proportion of cycloaliphatic diisocyanates of at least 25 mol %; the equivalent ratio of (b)/(a) being from 1.4 to 2.5; and (2) hydrazine as chain lengthening agent; and from 1 to 10 parts, by weight, of a melamine-formaldehyde resin and/or a urea-formaldehyde resin; and that self supporting sheets produced from the bonding coat pastes have microhardness (Shore A)≦ 50 and moduli (at 100%)≦ 15 kp/cm 2 .
Claim 2
Dependent Claim 190 words
Process for the production of textile coatings which have an exceptionally soft hand resembling that of napa leather by applying a polurethane paste which contains melamine formaldehyde resins and/or urea-formaldehyde resins as a bonding coat and another polyurethane paste as top coat to textile supports in the form of webs by the reversal process followed by evaporation of the solvent or dispersing agent and simultaneous acid catalysed cross-linking of the components of the bonding coat, characterised in that the bonding coats used are pastes with a solids content of from 30 to 70%, by weight, consisting of: 100 parts, by weight, of a polyurethane from (1) a prepolymer from (a) dihydroxy polyesters or dihydroxy polyethers; and (b) aliphatic and/or cycloaliphatic diisocyanates with a proportion of cycloaliphatic diisocyanates of at least 25 mol %; the equivalent ratio of (b)/(a) being from 1.4 to 2.5; and (2) hydrazine as chain lengthening agent; and from 1 to 10 parts, by weight, of a melamine-formaldehyde resin and/or a urea-formaldehyde resin; and that self supporting sheets produced from the bonding coat pastes have microhardness (Shore A)≦ 50 and moduli (at 100%)≦ 15 kp/cm 2 .
Claim 3
Dependent Claim 30 words
Process according to claim 1, characterised in that the bonding coat pastes contain from 4 to 6 parts by weight, of formaldehyde resin to 100 parts, by weight, of polyurethane.
Claim 4
Dependent Claim 46 words
Process according to claim 1, characterised in that dihydroxypolyesters from adipic acid, and diols selected from the group consisting of ethylene glycol, diethylene glycol and butane-1,4-diol having a molecular weight of from 1800 to 3000 are used for synthesising the polyurethane of the bonding coat paste.
Claim 5
Dependent Claim 35 words
Process according to claim 1, characterised in that dihydroxybutylene glycol polyethers or dihydroxypropylene glycol polyethers having a molecular weight of from 1800 to 3000 are used for synthesising the polyurethane of the bonding coat paste.
Claim 6
Dependent Claim 34 words
Process according to claim 1, characterised in that a mixture of hexane-1,6-diisocyanate and 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane is used in a molar ratio of from 1:3 to 3:1 for synthesising the polyurethane of the bonding coat paste.

References Cited (Backward Citations)

US3398042A Cited
US3650880A Cited
US3844862A Cited
US3900688A Cited
US3922402A Cited
US3939021A Cited
US3941633A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-07-11 1981-01-10 1981-07-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-07-11 1985-01-10 1985-07-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-07-11 1989-01-10 1989-07-12 $7700.00 Window Closed / Lapsed

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