Patent US3630833A successfully refreshed from Google Patents.
US3630833A
Expired / Lapsed
US
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Process for making moisture resistant, stiffened paper containing isoprene resin and product
Assignee: Georgia-Pacific LLC
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Filing: 1969-02-12
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Granted: 1971-12-28
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Expires: 1989-02-12
Abstract
Abstract An aqueous mixture of lignosulfonate and an isoprene resin ground to particulate form having a melting point of 80-130* C. in the ratio of liquosulfonate to isoprene resin in the range of 0.2:1 to 4:1 based on the dry weights is added to an aqueous slurry of cellulosic fibers. The aqueous mixture of liquosulfonate and resin can be stabilized with acetic acid or a mixture of acetic acid and an alkali metal acetate. A paper web is formed from the slurry, dewatered and heated to a temperature exceeding the melting point of the isoprene resin to fix the resin onto the cellulosic fibers without requiring a fixing agent.
Inventors
- 👤 Rodger L Fife
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:16
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/21; D21H17/23
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
65 words
A process according to claim 1 wherein the isoprene resin and lignosulfonate are mixed in the presence of an acetic acid stabilizer present in an amount from 0.001 to 1 weight percent, based upon the dry weight of the isoprene resin and lignosulfonate solids, prior to intermixing with the cellulosic fiber. A process according to claim 2 wherein the lignosulfonate is a spent sulfite liquor.
Claim 2
Dependent Claim
52 words
A process according to claim 3 wherein the ratio of the spent sulfite liquor solids to the resin is in the range of from 0.75:1 to 2.0:1, and the stabilizer is a mixture of acetic acid and an alkali metal acetate present in an amount of from 0.01 to 0.1 weight percent.
Claim 3
Dependent Claim
29 words
A process according to claim 4 wherein the spent sulfite liquod solids-resin mixture is intermixed with the cellulosic fibers in an amount of from 0.5 to 2 weight percent.
Claim 4
Dependent Claim
43 words
A process according to claim 5 wherein the cellulosic fibers intermixed with the mixture of spent sulfite liquor and isoprene resin are subsequently dewatered and heated at a temperature exceeding the melting point of the isoprene resin by from 20* to 100* C.
Claim 5
Dependent Claim
34 words
A process according to claim 6 wherein the paper sheet is heated at a temperature in the range of from 40* to 60* C. in excess of the melting point of the isoprene resin.
Claim 6
Dependent Claim
10 words
A paper sheet obtained by the process of claim 1.
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) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |