US3852136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of laminated glazing
Assignee: AGC Glass Europe SA
•
Filing: 1972-08-25
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Granted: 1974-12-03
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Expires: 1992-08-25
Abstract
Abstract A process and apparatus for forming a laminate by heating an assembly of at least two sheets of glass or vitrocrystalline material with a thermoplastic layer in the intersheet spaces between adjacent sheets. A preliminary treatment of the assembly takes place within an enclosure in which the assembly is heated to soften the thermoplastic layers and in which the heated assembly is exposed to a sub-atmospheric environmental pressure while the intersheet spaces at the peripheral margins of the assembly are subjected to a suction pressure substantially less than that of the sub-atmospheric environmental pressure. At the completion of the preliminary treatment the assembly is conveyed to another enclosure in which the assembly is exposed to higher temperatures than those used in the preliminary treatment so as to firmly bond the sheets by means of the thermoplastic layers.
Inventors
- 👤 E Plumat
- 👤 Laethem R Van
- 👤 P Votquenne
- 👤 P Colignon
- 👤 M Wasterlain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:46
CPC Classifications
B; B32; B32B; B32B17/00; B32B17/06; B32B17/10; B32B17/10005; B32B17/1055; B32B17/10761; B32B17/10807; B32B17/10816; B32B17/10825; B32B17/10834; B32B17/10844; B32B17/10853; B32B17/10871; B32B37/00; B32B37/0007; E; E06; E06B; E06B7/00; E06B7/28; B32B2309/00; B32B2309/60; B32B2309/68
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
120 words
In a process of forming a laminate by heating an assembly including at least two sheets of glass or vitrocrystalline material and an intervening thermoplastic layer, to at least soften the thermoplastic layer, and applying pressure to and heating the assembly sufficiently to firmly bond the sheets by means of such thermoplastic layer, the improvement prior to the step of applying pressure to and heating the assembly, comprising the steps of: simultaneously applying a sub-atmospheric environmental pressure to the assembly and heating the assembly to soften the thermoplastic layer and applying along the margins of the assembly a sub-atmospheric pressure which is lower than the sub-atmospheric environmental pressure applied to the assembly, whereby the intersheet spaces are subjected to suction.
Claim 2
Dependent Claim
120 words
In a process of forming a laminate by heating an assembly including at least two sheets of glass or vitrocrystalline material and an intervening thermoplastic layer, to at least soften the thermoplastic layer, and applying pressure to and heating the assembly sufficiently to firmly bond the sheets by means of such thermoplastic layer, the improvement prior to the step of applying pressure to and heating the assembly, comprising the steps of: simultaneously applying a sub-atmospheric environmental pressure to the assembly and heating the assembly to soften the thermoplastic layer and applying along the margins of the assembly a sub-atmospheric pressure which is lower than the sub-atmospheric environmental pressure applied to the assembly, whereby the intersheet spaces are subjected to suction.
Claim 3
Dependent Claim
31 words
A process as defined in claim 1 wherein the steps carried out prior to the step of applying pressure to and heating the assembly are all initiated at the same time.
Claim 4
Dependent Claim
45 words
A process as defined in claim 2 wherein the sub-atmospheric environmental pressure which is applied to the assembly is maintained at that pressure level for a period of time and is then increased while the sub-atmospheric pressure on the margins of the assembly is maintained.
Claim 5
Dependent Claim
21 words
A process as defined in claim 3 wherein the heating of the assembly is continued following the increase of environmental pressure.
Claim 6
Dependent Claim
18 words
A process as defined in claim 3 wherein the sub-atmospheric environmental pressure is increased to atmospheric environmental pressure.
Claim 7
Dependent Claim
34 words
A process as defined in claim 5 wherein the sub-atmospheric pressure along the margins of the assembly is terminated after a period of time following the increase in the environmental pressure to atmospheric pressure.
Claim 8
Dependent Claim
29 words
A process as defined in claim 6 wherein following the termination of the sub-atmospheric presSure along the margins of the assembly the temperature of the assembly is progressively increased.
Claim 9
Dependent Claim
24 words
A process as defined in claim 7 wherein the temperature of the assembly is progressively increased from a starting temperature which is above 100*C.
Claim 10
Dependent Claim
32 words
A process as defined in claim 1 wherein the sub-atmospheric pressure to which the intersheet spaces are exposed at the margins of the assembly is not more than 10 mm of mercury.
Claim 11
Dependent Claim
26 words
A process as defined in claim 1 wherein the sub-atmospheric environmental pressure to which the assembly is exposed is not more than 400 mm of mercury.
Claim 12
Dependent Claim
28 words
A process as defined in claim 1 wherein the temperature of the assembly is progressively increased prior to the step of applying pressure to and heating the assembly.
Claim 13
Dependent Claim
25 words
A process as defined in claim 11 wherein the step of heating the assembly to soften the thermoplastic layer is initiated at an elevated temperature.
Claim 14
Dependent Claim
20 words
A process as defined in claim 12 wherein the assembly is not preheated prior to heating at an elevated temperature.
Claim 15
Dependent Claim
15 words
A process as defined in claim 12 wherein the elevated temperature is at least 60*C.
Claim 16
Dependent Claim
46 words
A process as defined in claim 1 wherein, during at least the initiation of the step of heating the assembly to soften the thermoplastic layer, a temperature gradient is maintained between a central zone of the assembly and a zone at the margins of the assembly.
Claim 17
Dependent Claim
52 words
A process as defined in claim 15 wherein the central zone of the assembly is maintained at a temperature which is below a preliminary bonding temperature of the thermoplastic layer and the marginal zone is progressively heated up to a temperature at which the plastic material begins to stick to the glass.
Claim 18
Dependent Claim
42 words
A process as defined in claim 16 wherein the central zone is insulated from the source of heat in order to maintain that zone at a temperature lower than the temperature at which the plastic material begins to stick to the glass.
Claim 19
Dependent Claim
59 words
A process as defined in claim 17 wherein a plurality of assemblies are disposed along their respectively longitudinal edges to be in spaced relationship but in relatively close proximity to each other to insulate the central zones of the assemblies from the source of heat and confine the heating of the assemblies to the marginal zones of these assemblies.
Claim 20
Dependent Claim
43 words
A process as defined in claim 17 wherein the central zone of an assembly is insulated from the source of heat by a refractory screen which is inserted between the heat source and the faces of the assembly at the central zone thereof.
Claim 21
Dependent Claim
48 words
A process as defined in claim 16 wherein, after the bonding of the marginal zone of the assembly has been carried out, the temperature of the central zone and that of the marginal zone are progressively equalized by extending the action of the heat to the central zone.
Claim 22
Dependent Claim
32 words
A process as defined in claim 20 wherein the action of the heat is extended to the central zone by a forced circulation of the quantities of gas which enclose an assembly.
Claim 23
Dependent Claim
33 words
A process as defined in claim 21 wherein the action of the heat is extended to the central zone by removing refractory screens positioned between the source of heat and the central zone.
Claim 24
Dependent Claim
18 words
A process as defined in claim 15 wherein the heating of the assembly is achieved by heat radiation.
Claim 25
Dependent Claim
27 words
A process as defined in claim 15 wherein the tmeperature gradient is maintained at least until the sub-atmospheric pressure along the margins of the assembly is interrupted.
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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) | 1977-12-02 | 1978-06-03 | 1978-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-02 | 1982-06-03 | 1982-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-02 | 1986-06-03 | 1986-12-03 | $7700.00 | Window Closed / Lapsed |