Patent US3904377A successfully refreshed from Google Patents.
US3904377A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lightweight composite containing hollow glass microspheres
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1973-07-23
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Granted: 1975-09-09
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Expires: 1993-07-23
Abstract
Abstract When finely divided SHIRASU (pumice ejected from volcanoes and the secondary deposit of such pumice) is roasted at a temperature in the range of from about 800* to about 1200*C, the vitreous particles contained in said SHIRASU foam and consequently produce light-weight hollow glass microspheres. The hollow glass microspheres so produced are superior to conventional glass microspheres especially in their resistance to heat and can therefore be combined with metal, carbon, as well as with cement and other materials to produce novel lightweight composites.
Inventors
- 👤 Hidemasa Honda
- 👤 Yukio Isayama
- 👤 Kazuhiko Jinnai
- 👤 Kunio Kimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:14
CPC Classifications
C; C03; C03C; C03C11/00; C03C11/002; C04; C04B; C04B14/00; C04B14/02; C04B14/04; C04B14/14; C04B14/16
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
57 words
A COMPOSITE MATERIAL ESSENTIALLY CONSISTING OF A METAL AND OF HOLLOW GLASS MICROSPHERES DISPERSED IN SAID METAL, SAID METAL BEING FREE FROM VOIDS THE MELTING POINT OF SAID METAL BEING LOWER THAN THE MELTING POINT OF THE GLASS IN SAID MICROSPHERES, SAID MICROSPHERES BEING PRODUCED BY SINTERING PUMICE PARTICLES SMALLER THAN 250 MICRONS AT 800* TO 1200*C
Claim 2
Dependent Claim
57 words
A COMPOSITE MATERIAL ESSENTIALLY CONSISTING OF A METAL AND OF HOLLOW GLASS MICROSPHERES DISPERSED IN SAID METAL, SAID METAL BEING FREE FROM VOIDS THE MELTING POINT OF SAID METAL BEING LOWER THAN THE MELTING POINT OF THE GLASS IN SAID MICROSPHERES, SAID MICROSPHERES BEING PRODUCED BY SINTERING PUMICE PARTICLES SMALLER THAN 250 MICRONS AT 800* TO 1200*C
Claim 3
Dependent Claim
35 words
A composite material according to claim 1, wherein the volume of the hollow glass microspheres is not less than 30 percent and not more than 80 percent of the apparent volume of the composite material.
Claim 4
Dependent Claim
26 words
A composite material according to claim 1, wherein the metal is at least one member selected from the group consisting of aluminum, zinc, lead and tin.
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) | 1978-09-08 | 1979-03-10 | 1979-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-08 | 1983-03-10 | 1983-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-08 | 1987-03-10 | 1987-09-09 | $7700.00 | Window Closed / Lapsed |