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US4576970A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the production of molded articles having integral skin

Assignee: Bayer AG
•
Filing: 1985-02-21
•
Granted: 1986-03-18
•
Expires: 2005-02-21
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Abstract

Abstract The present invention is directed to a process for the production of a molded article having a compact surface layer and a gross density above 900 kg/m 3 via the reaction injection molding technique, comprising introducing a reaction mixture into a closed mold, said reaction mixture comprising: (a) a polyisocyanate component consisting of at least one polyisocyanate in which all the isocyanate groups are aromatically bound, (b) compounds having molecular weights of from 400 to 12,000 and having at least two isocyanate reactive hydrogen atoms, (c) water, in a quantity of at least 0.15 mol per mol of isocyanate groups of component (a), and (d) optionally compounds having molecular weights of from 60 to 399 and having at least two isocyanate reactive hydrogen atoms, wherein the isocyanate index, based on all the reactants taking part in the reaction is from 70 to 125, and wherein a pressure of above 40 bar is maintained in the reaction mixture during the reaction so that the carbon dioxide formed in the course of the reaction remains completely or predominantly in solution in the reaction mixture and in the molded article produced.

Inventors

  • 👤 Otto Ganster
  • 👤 Ulrich Knipp
  • 👤 Bruno Luckas

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 17:51
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/65; C08G18/66; C08G18/6603; C08G18/30; C08G18/302; C08G2120/00; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249987; Y10T428/249988; Y10T428/249989

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 194 words
A process for the production of a molded article having a compact surface layer and a gross density above 900 kg/m 3 via the reaction injection molding technique, comprising introducing a reaction mixture into a closed mold, said reaction mixture comprising: (a) a polyisocyanate component consisting of at least one polyisocyanate in which all the isocyanate groups are aromatically bound, (b) compounds having molecular weights of from 400 to 12,000 and having at least two isocyanate reactive hydrogen atoms, (c) water, in a quantity of at least 0.15 mol per mol of isocyanate groups of component (a), and (d) optionally compounds having molecular weights of from 60 to 399 and having at least two isocyanate reactive hydrogen atoms, wherein the isocyanate index, based on all the reactants taking part in the reaction is from 70 to 125, maintaining a pressure of above 40 bar in the reaction mixture during the reaction so that the carbon dioxide formed in the course of the reaction remains completely or predominately in solution in the reaction mixture and in the molded article produced, and removing the resulting molded articles from the mold after termination of the chemical reaction.
Claim 2
Dependent Claim 194 words
A process for the production of a molded article having a compact surface layer and a gross density above 900 kg/m 3 via the reaction injection molding technique, comprising introducing a reaction mixture into a closed mold, said reaction mixture comprising: (a) a polyisocyanate component consisting of at least one polyisocyanate in which all the isocyanate groups are aromatically bound, (b) compounds having molecular weights of from 400 to 12,000 and having at least two isocyanate reactive hydrogen atoms, (c) water, in a quantity of at least 0.15 mol per mol of isocyanate groups of component (a), and (d) optionally compounds having molecular weights of from 60 to 399 and having at least two isocyanate reactive hydrogen atoms, wherein the isocyanate index, based on all the reactants taking part in the reaction is from 70 to 125, maintaining a pressure of above 40 bar in the reaction mixture during the reaction so that the carbon dioxide formed in the course of the reaction remains completely or predominately in solution in the reaction mixture and in the molded article produced, and removing the resulting molded articles from the mold after termination of the chemical reaction.
Claim 3
Dependent Claim 29 words
The process of claim 1, wherein polyisocyanate component (a) comprises polyisocyanate or polyisocyanate mixtures of the diphenyl methane series which may be modified with urethane, carbodiimide and/or isocyanurate groups.
Claim 4
Dependent Claim 22 words
The process of claim 1, wherein compound (b) comprises polyester polyols and/or polyether polyols having molecular weights of from 400 to 12,000.

References Cited (Backward Citations)

US4065410A Cited
US4218543A Cited
US4292411A Cited
US4272618A Cited
US4416844A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-03-17 1989-09-16 1990-03-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-03-17 1993-09-16 1994-03-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-03-17 1997-09-16 1998-03-18 $7700.00 Window Closed / Lapsed

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