US4908164A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Procedure for the production of magnetic plastic laminate
Assignee: S I P A P Sas Di Demichelis Margherita and C
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Filing: 1988-03-30
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Granted: 1990-03-13
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Expires: 2008-03-30
Abstract
Abstract Procedure for the production of magnetic plastic laminate in which at least one of the paper fiber sheets impregnated with phenolic and melaminic resins, is first of all spread, using the silk screen process, with a cloth with a weave of from 9 to 24 threads per cm 2 , with a ferrous powder based paste with a percentage comprised of between 55%-80% and a binder with a percentage comprised of between 45%-20%; after drying the percentage of ferrous powders is comprised of between 75%-80%, the thickness of the paste of between 0.5 and 2.0 mm and the plastic laminate thus obtained is permanently magnetized through an electric charge thanks to the presence of the ferrous powders inside it.
Inventors
- 👤 Giovanni Brussino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:28
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/88; B29C70/887; B32; B32B; B32B29/00; B32B29/002; B32B27/00; B32B27/18; B32B37/00; B32B37/14; B32B37/15; B32B37/156; H; H01; H01F; H01F1/00; H01F1/0027; H01F41/00; H01F41/14; H01F41/16; B29K; B29K2705/00; B29K2711/00; B29K2711/12; B32B2255/00; B32B2255/12; B32B2255/20; B32B2255/205; B32B2260/00; B32B2260/02; B32B2260/028; B32B2260/04; B32B2260/046; B32B2307/00; B32B2307/20; B32B2307/208; B32B2309/00; B32B2309/08; B32B2309/10; B32B2309/105; B32B2317/00; B32B2317/12; B32B2317/122; B32B2479/00; B32B2601/00; B32B2607/00; Y; Y10; Y10S; Y10S264/00; Y10S264/58; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/257; Y10T428/31504; Y10T428/31942; Y10T428/31949; Y10T428/31964
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
162 words
A process for producing a magnetic plastic laminate, said process comprising the steps of: impregnating at least three sheets of paper fiber with phenolic and melaminic resins and oven drying the impregnated paper fiber sheets; applying a paste on at least one of said dried impregnated paper fiber sheets, said paste comprising a ferrous powder in an amount of 55% to 80% and a binder in an amount of 45% to 20%, said binder being a resin; drying said paper fiber sheet having paste thereon, the thickness of the paste after drying being between 0.5 and 2.0 mm and the percentage of ferrous powder in the paste after drying being between 75% and 85%; inserting said paper fiber sheet having paste thereon between the other two dried impregnated paper fiber sheets and hot pressing the resultant layered structure to produce a laminate; and then applying an electrical charge to said laminate to permanently magnetize the laminate thereby producing a magnetic plastic laminate.
Claim 2
Dependent Claim
162 words
A process for producing a magnetic plastic laminate, said process comprising the steps of: impregnating at least three sheets of paper fiber with phenolic and melaminic resins and oven drying the impregnated paper fiber sheets; applying a paste on at least one of said dried impregnated paper fiber sheets, said paste comprising a ferrous powder in an amount of 55% to 80% and a binder in an amount of 45% to 20%, said binder being a resin; drying said paper fiber sheet having paste thereon, the thickness of the paste after drying being between 0.5 and 2.0 mm and the percentage of ferrous powder in the paste after drying being between 75% and 85%; inserting said paper fiber sheet having paste thereon between the other two dried impregnated paper fiber sheets and hot pressing the resultant layered structure to produce a laminate; and then applying an electrical charge to said laminate to permanently magnetize the laminate thereby producing a magnetic plastic laminate.
Claim 3
Dependent Claim
36 words
A process according to claim 1, wherein said paste is applied on said at least one impregnated paper fiber sheet by silk screening using a weave of from 9 to 24 threads per cm 2 .
Claim 4
Dependent Claim
32 words
A process according to claim 1, wherein said ferrous powder is obtained from the grinding of ferrite, which ferrite is obtained through the sintering of ferrous oxides and barium and strontium carbonates.
Claim 5
Dependent Claim
25 words
A process according to claim 1, wherein said binder is a member selected from the group consisting of acrylic resins, melaminic resins and mixtures thereof.
Claim 6
Dependent Claim
20 words
A process according to claim 1, wherein the percentage of ferrous powder in said paste is between 65% and 75%.
Claim 7
Dependent Claim
19 words
A process according to claim 1, wherein the percentage of binder in said paste is between 35% and 25%.
Claim 8
Dependent Claim
20 words
A process according to claim 1, wherein the percentage of ferrous powder in said paste after drying is about 80%.
Claim 9
Dependent Claim
18 words
A process according to claim 1, wherein the thickness of the paste after drying is about 2.0 mm.
Claim 10
Dependent Claim
32 words
A process according to claim 1, wherein the paste is applied by silk screening using a cloth with a weave made up of from 9 to 15 threads per cm 2 .
Claim 11
Dependent Claim
13 words
A process according to claim 1, wherein the paste is applied by calendaring.
Claim 12
Dependent Claim
13 words
A process according to claim 1, wherein the paste is applied by spraying.
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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) | 1993-03-12 | 1993-09-11 | 1994-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-12 | 1997-09-11 | 1998-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-12 | 2001-09-11 | 2002-03-13 | $7700.00 | Window Closed / Lapsed |