US3173748A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing a surface layer of high brightness on lignocellulosecontaining material
Assignee: Stiftelsen Wallboardindustriens Forskningsinstitut
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Filing: 1962-06-25
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Granted: 1965-03-16
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Expires: 1982-06-25
Abstract
No abstract record available.
Inventors
- 👤 Back Ernst Ludvig
- 👤 Eriksson Soren Ake Ivan
- 👤 Klinga Leif Olof
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:51
CPC Classifications
D; D06; D06L; D06L4/00; D06L4/30
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
65 words
A METHOD OF PROVIDING PRE-FORMED, DRIED LIGNOCELLULOSE-CONTAINING MATERIAL WITH ONLY A SURFACE LAYER OF HIGH BRIGHTNESS COMPRISING APPLYING A BLEACHING AGENT CONSISTING ESSENTIALLY OF REDUCING BLEACHING AGENTS TO SAID SURFACE OF THE PRE-FORMED AND DRIED LIGNOCELLULOSECONTAINING MATERIAL IN AN AMOUNT SUFFICIENT TO REACT WITH ONLY A SURFACE LAYER OF THE LATTER, AND PERMITTING THE REACTION PRODUCTS TO REMAIN IN THE SURFACE LAYER OF THE MATERIAL.
Claim 2
Independent Claim
65 words
A METHOD OF PROVIDING PRE-FORMED, DRIED LIGNOCELLULOSE-CONTAINING MATERIAL WITH ONLY A SURFACE LAYER OF HIGH BRIGHTNESS COMPRISING APPLYING A BLEACHING AGENT CONSISTING ESSENTIALLY OF REDUCING BLEACHING AGENTS TO SAID SURFACE OF THE PRE-FORMED AND DRIED LIGNOCELLULOSECONTAINING MATERIAL IN AN AMOUNT SUFFICIENT TO REACT WITH ONLY A SURFACE LAYER OF THE LATTER, AND PERMITTING THE REACTION PRODUCTS TO REMAIN IN THE SURFACE LAYER OF THE MATERIAL.
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) | 1968-03-15 | 1968-09-14 | 1969-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-03-15 | 1972-09-14 | 1973-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-03-15 | 1976-09-14 | 1977-03-16 | $7700.00 | Window Closed / Lapsed |