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US4335218A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the preparation of a foam-cored laminate having metal facers and rigid polyisocyanurate foam core prepared in the presence of a dipolar aprotic organic solvent

Assignee: Dow Chemical Co
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Filing: 1980-10-27
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Granted: 1982-06-15
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Expires: 2000-10-27
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Abstract

Abstract Improved adhesion between the skin and core of laminates having rigid polyisocyanurate foam cores is obtained by incorporating a dipolar aprotic organic solvent, in minor amount, into the reaction mixture employed to prepare the polyisocyanurate foam core.

Inventors

  • 👤 David T. DeGuiseppi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 19:48
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/18; B32B15/00; B32B15/04; B32B15/046; C; C08; C08J; C08J5/00; C08J5/12; C08J9/00; C08J9/0014; C08J2379/00; C08J2379/04; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31547

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 85 words
In a process for the preparation of a foam-cored laminate having metal facers and rigid polyisocyanurate foam as the core material the improvement which comprises lowering the cure temperature necessary to assure good adhesion between metal facer and foam core by incorporating, into the polyisocyanurate foam forming reaction mixture which is employed to prepare the foam core, a dipolar aprotic solvent in an amount from about 1 percent by weight to about 10 percent by weight based on total weight of the foam forming mixture.
Claim 2
Dependent Claim 85 words
In a process for the preparation of a foam-cored laminate having metal facers and rigid polyisocyanurate foam as the core material the improvement which comprises lowering the cure temperature necessary to assure good adhesion between metal facer and foam core by incorporating, into the polyisocyanurate foam forming reaction mixture which is employed to prepare the foam core, a dipolar aprotic solvent in an amount from about 1 percent by weight to about 10 percent by weight based on total weight of the foam forming mixture.
Claim 3
Dependent Claim 14 words
A process according to claim 1 wherein the dipolar aprotic organic solvent is dimethylformamide.
Claim 4
Dependent Claim 15 words
A process according to claim 1 wherein the dipolar aprotic organic solvent is O,O-dimethyl methylphosphonate.
Claim 5
Dependent Claim 14 words
A process according to claim 1 wherein the dipolar aprotic organic solvent is dimethylsulfoxide.
Claim 6
Dependent Claim 38 words
A process according to claim 1 wherein the polyisocyanurate foam forming reaction mixture comprises a polymethylene polyphenyl polyisocyanate, a minor amount, based on equivalents per equivalent of polyisocyanate, of a polyol, a blowing agent and a trimerization catalyst.
Claim 7
Dependent Claim 57 words
A process according to claim 5 wherein the polyol in the polyisocyanurate foam forming reaction mixture comprises a polyol mixture prepared by the transesterification, with a glycol of molecular weight from about 60 to about 400, of a residue remaining after dimethyl terephthalate and methyl p-toluate have been removed from a dimethyl terephthalate esterified oxidate reaction product.

References Cited (Backward Citations)

US3625872A Cited
US3849349A Cited
US3746709A Cited
US3940517A Cited
US3896052A Cited
US3903018A Cited
US4024310A Cited
US4025687A 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) 1985-06-14 1985-12-14 1986-06-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-06-14 1989-12-14 1990-06-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-06-14 1993-12-14 1994-06-15 $7700.00 Window Closed / Lapsed

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