Patent EP0239877A2 successfully refreshed from Google Patents.
EP0239877A2
Expired / Lapsed
EP
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Method for producing composite structures with a polyurethane interior, and the composite structure obtained
Assignee: ERREBI Srl
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Filing: 1987-03-18
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Granted: —
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Expires: 2007-03-18
Abstract
Abstract In the method for producing composite structures comprising at least one layer of polymethylmethacrylate (3, 4) and at least one layer of polyurethane (5), in which the polyurethane formation reaction takes place in contact with the polymethylmethacrylate, the polymethylmethacrylate used is of impact resistant type, the polyurethane is of rigid compact or semiexpanded type, and the composite structure is formed by heating the polymethylmethacrylate layer to between 40 and 70°C and applying a vacuum to it. The composite structure comprises at least one layer of impact resistant polymethylmethacrylate and at least one layer of rigid polyurethane.
Inventors
- 👤 Carlo Besozzi
- 👤 Angelo Pozzi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 13:23
CPC Classifications
B; B29; B29C; B29C39/00; B29C39/02; B29C39/12; B29C39/123; B29C39/126; B32; B32B; B32B27/00; B32B27/06; B32B27/065; B29C44/00; B29C44/02; B29C44/12; B29C44/14; B29C51/00; B29C51/002; B29C70/00; B29C70/58; B29C70/66; B32B27/30; B32B27/308; B32B27/40; B32B38/00; B32B38/0036; B32B38/18; B32B38/1858; B32B5/00; B32B5/18; B32B5/20; B29K; B29K2033/00; B29K2033/04; B29K2033/12; B29K2075/00; B29K2105/00; B29K2105/06; B29K2105/16; B29K2105/165; B29L; B29L2031/00; B29L2031/769; B29L2031/7694; B32B2266/00; B32B2266/02; B32B2266/0214; B32B2266/0278; B32B2309/00; B32B2309/60; B32B2309/68
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
75 words
A method for producing composite structures comprising at least one layer of polymethylmethacrylate and at least one layer of polyurethane, in which the polyurethane formation reaction takes place in contact with the polymethylmethacrylate, characterized in that the polymethylmethacrylate used is of impact resistant type, the polyurethane is of rigid compact or semiexpanded type, and the composite structure is formed by heating the polymethymethacrylate layer to between 40 and 70°C and applying a vacuum to it.
Claim 2
Independent Claim
75 words
A method for producing composite structures comprising at least one layer of polymethylmethacrylate and at least one layer of polyurethane, in which the polyurethane formation reaction takes place in contact with the polymethylmethacrylate, characterized in that the polymethylmethacrylate used is of impact resistant type, the polyurethane is of rigid compact or semiexpanded type, and the composite structure is formed by heating the polymethymethacrylate layer to between 40 and 70°C and applying a vacuum to it.
Claim 3
Dependent Claim
19 words
A method as claimed in claim 1, characterized in that the polymethylmethacrylate has a thickness not exceeding 1.2 mm.
Claim 4
Independent Claim
22 words
A method as claimed in claims 1 and 2, characterized in that the impact resistant polymetylmethacrylate layer is previously shaped by vacuum-forming.
Claim 5
Independent Claim
25 words
A method as claimed in the preceding claims, characterized in that the vacuum-forming and the rigid polyurethane formation reaction take place in the same mould.
Claim 6
Independent Claim
31 words
A method as claimed in at least one of the preceding claims, characterized in that the vacuum-forming is implemented in one mould and the filling with the polyurethane mixture in another.
Claim 7
Independent Claim
27 words
A method as claimed in one or more of the preceding claims, characterized in that the impact resistant polymethylmethacrylate layer at least partially surrounds the rigid polyurethane.
Claim 8
Independent Claim
106 words
A method as claimed in at least one of the preceding claims, characterized in that the mixture comprises polyol, isocyanate and a catalyst, and possibly inserts and expanding agents, the polyol being a mixture of polyol having several hydroxyl groups per molecula and a mean molecular weight of about 1300, it deriving from the reaction of alcohols, such as sorbitol, saccharose, glycerin and the like, with alkylene oxides of ethylene and propylene type, the isocyanate being formed from a mixture of diphenylmethane-4,4ʹ-diisocyanate and polymers thereof, the catalyst being at least one component of the group consisting of stannous compounds (stannous octoate), tertiary amines and their mixtures.
Claim 9
Independent Claim
27 words
A method as claimed in at least one of the preceding claims, characterized in that the polyol/isocyanate weight ratio in the mixture lies between 1:0.95 and 1:1.05.
Claim 10
Independent Claim
35 words
A method as claimed in at least one of the preceding claims, characterized in that the inerts are present in the mixture to the extent of 5-60 parts by weight per 100 parts of polyol.
Claim 11
Dependent Claim
16 words
A method as claimed in claim 1, characterized in that the applied vacuum exceeds 350 mmHg.
Claim 12
Independent Claim
80 words
A method as claimed in at least one of the preceding claims, characterized in that in order to produce structures in which the impact resistant polymetylmethacrylate layer defines at least one cavity in which the rigid polyurethane is contanied and the impact resistant polymetylmethacrylate layer is obtained from at least two sheets at least one of which is vacuum-formed, after the sheet or sheets have been formed the sheets are joined together by welding and the excess parts are removed.
Claim 13
Dependent Claim
47 words
A composite structure characterized by comprising at least one at least partial layer of impact resistant polymetylmethacrylate (PMMA) of small thickness which in any event does not exceed 1.2 mm, and a least one layer of rigid compact or semiexpanded polyurethane, these layers being irreversibly joined together.
Claim 14
Dependent Claim
47 words
A composite structure characterized by comprising at least one at least partial layer of impact resistant polymetylmethacrylate (PMMA) of small thickness which in any event does not exceed 1.2 mm, and a least one layer of rigid compact or semiexpanded polyurethane, these layers being irreversibly joined together.
References Cited (Backward Citations)
No citation records indexed.
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