US3607178A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treating glass sheets used in laminated safety glass windshields
Assignee: PPG Industries Inc
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Filing: 1968-09-19
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Granted: 1971-09-21
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Expires: 1988-09-19
Abstract
Abstract Rinsing glass sheets prior to their lamination in water having a hardness in a controlled range, preferably between about 200 and about 400 parts by weight of calcium and/or magnesium expressed in terms of calcium carbonate per million parts by weight of water and preferably containing a mixture containing more calcium ions than magnesium ions.
Inventors
- 👤 Brook J Dennison
- 👤 Albert A Doutt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:40
CPC Classifications
B; B32; B32B; B32B17/00; B32B17/06; B32B17/10; B32B17/10005; B32B17/10807; B32B17/10981; C; C03; C03C; C03C23/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
40 words
The improvement according to claim 1, wherein said glass sheets are rinsed with said treated water having a hardness of about 400 parts by weight calculated as calcium carbonate per million parts by weight of solution before they are bent.
Claim 2
Dependent Claim
46 words
The improvement according to claim 2, wherein said glass sheets are rinsed with said water treated to have a hardness of about 200 parts by weight calculated as calcium carbonate per million parts by weight of solution after they are bent and before they are laminated.
Claim 3
Dependent Claim
19 words
The improvement as in claim 1 wherein said additive solution contains a mixture of calcium ions and magnesium ions.
Claim 4
Dependent Claim
19 words
The improvement as in claim 4, wherein said added solution contains calcium chloride and magnesium sulfate as essential ingredients.
Claim 5
Dependent Claim
22 words
The improvement as in claim 4, wherein a greater amount of calcium ions than magnesium ions are included in said additive solution.
Claim 6
Dependent Claim
24 words
The improvement according to claim 6, wherein the ratio of calcium ions to magnesium ions in said additive solution is approximately 2 to 1.
Claim 7
Dependent Claim
17 words
The improvement according to claim 1, wherein the glass sheets so treated are composed of float glass.
Claim 8
Dependent Claim
57 words
The improvement according to claim 1, wherein aT least one of said sheets to be laminated is treated at a temperature below the boiling point of water with an aqueous dispersion of a diatomaceous earth on a surface previously rinsed with water having a hardness of approximately 400 parts by weight per million calculated as calcium carbonate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |