Patent US3914338A successfully refreshed from Google Patents.
US3914338A
Expired / Lapsed
US
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Opalescent methylmethacrylate polymer bodies
Assignee: Roehm GmbH Darmstadt
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Filing: 1973-12-26
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Granted: 1975-10-21
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Expires: 1993-12-26
Abstract
Abstract Polymer particles consisting of a core of a cross-linked styrene polymer having a shell of a methyl methacrylate polymer graft copolymerized thereon. Methods of making such polymer particles. Opalescent bodies of a methyl methacrylate polymer having such polymer particles dispersed therein as the opalescing agent. Method of making such opalescent bodies.
Inventors
- 👤 Manfred Krieg
- 👤 Norbert Suetterlin
- 👤 Hans-Dieter Blitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:35
CPC Classifications
C; C08; C08F; C08F257/00; C08F257/02; C08F285/00; Y; Y10; Y10S; Y10S525/00; Y10S525/902; Y10S525/932
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
208 words
AN OPALESCENT BODY OF POLYMETHYLMETHACRYLATE OR OF A COPOLYMER COMPRISING AT LEAST 50 PERCENT BY WEIGHT OF METHYL METHACRYLATE, THE BALANCE BEING A VINYL OR VINYLIDENE COMONOMER COPLYMERIZABLE THEREWITH, SAID BODY HAVING OPALESCING PARTICLES DISPERED THEREIN IN AN AMOUNT FROM ABOUT 0.1 TO 5 PERCENT BY WEIGHT OF SAID BODY, SAID PARTICLES CONSISTING ESSENTIALLY OF A CORE, GREATER THAN ABOUT 0.8 IN DIAMETER, OF CROSSLINKED POLYSTYRENE OR OF A CROSS-LINKED COPOLYMER COMPRISING AT LEAST 50 PERCENT BY WEIGHT OF STYRENE, THE BALANCE BEING A VINYL OR VINYLIDENE COMONOMER FORMING A HOMOPOLYMER WHOSE INDEX OF REFRACTION ND20 IS GREATER THAN 1.50, SAID COR BEING CROSS-LINKED BY THE PRESENCE THEREIN OF ABOUT 0.5 TO 5 PERCENT, BY WEIGHT OF STYRENE OR MONOMER MIXTURE PREDOMINANTY COMPRISING STYRENE, OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF N-ALKOXY ALKYL METHACRYLAMIDES AND ETHYLENICALLY UNSATURATED MONOMERS HAVING AT LEAST TWO CARBONCARBON DOUBLE BONDS IN THE MOLECULE, SAID CORE FURTHER BEING SURROUNDED BY A GRAFT-COPOLYMERIZED SHELL OF POLYMETHYLMETHACRYLATE OR OF A COPOLYMER COMPRISING AT LEAST 50 PERCENT BY WEIGHT OF METHYL METHACRYLATE, THE BALANCE BEING A VINVL OR VINYLIDENE COMONOMER COPOLYMERIZABLE THEREWITH, THE VOLUME FRACTION OF SAID SHELL BEING AT LEAST 30 PERCENT AND UP TO 90 PERCENT OF THE TOTAL VOLUME OF SAID PARTICLES.
Claim 2
Dependent Claim
208 words
AN OPALESCENT BODY OF POLYMETHYLMETHACRYLATE OR OF A COPOLYMER COMPRISING AT LEAST 50 PERCENT BY WEIGHT OF METHYL METHACRYLATE, THE BALANCE BEING A VINYL OR VINYLIDENE COMONOMER COPLYMERIZABLE THEREWITH, SAID BODY HAVING OPALESCING PARTICLES DISPERED THEREIN IN AN AMOUNT FROM ABOUT 0.1 TO 5 PERCENT BY WEIGHT OF SAID BODY, SAID PARTICLES CONSISTING ESSENTIALLY OF A CORE, GREATER THAN ABOUT 0.8 IN DIAMETER, OF CROSSLINKED POLYSTYRENE OR OF A CROSS-LINKED COPOLYMER COMPRISING AT LEAST 50 PERCENT BY WEIGHT OF STYRENE, THE BALANCE BEING A VINYL OR VINYLIDENE COMONOMER FORMING A HOMOPOLYMER WHOSE INDEX OF REFRACTION ND20 IS GREATER THAN 1.50, SAID COR BEING CROSS-LINKED BY THE PRESENCE THEREIN OF ABOUT 0.5 TO 5 PERCENT, BY WEIGHT OF STYRENE OR MONOMER MIXTURE PREDOMINANTY COMPRISING STYRENE, OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF N-ALKOXY ALKYL METHACRYLAMIDES AND ETHYLENICALLY UNSATURATED MONOMERS HAVING AT LEAST TWO CARBONCARBON DOUBLE BONDS IN THE MOLECULE, SAID CORE FURTHER BEING SURROUNDED BY A GRAFT-COPOLYMERIZED SHELL OF POLYMETHYLMETHACRYLATE OR OF A COPOLYMER COMPRISING AT LEAST 50 PERCENT BY WEIGHT OF METHYL METHACRYLATE, THE BALANCE BEING A VINVL OR VINYLIDENE COMONOMER COPOLYMERIZABLE THEREWITH, THE VOLUME FRACTION OF SAID SHELL BEING AT LEAST 30 PERCENT AND UP TO 90 PERCENT OF THE TOTAL VOLUME OF SAID PARTICLES.
Claim 3
Dependent Claim
41 words
The method of making an opalescent body as in claim 1 comprises dispersing said particles into monomeric methyl methacrylate or a monomer mixture comprising at least 50 percent by weight of methyl methacrylate and then polymerizing said monomer or monomer mixture.
Claim 4
Dependent Claim
32 words
The method as in claim 2 wherein said particles are introduced into the monomer or monomer mixture in the form of a paste comprising said particles and methyl methacrylate or a plasticizer.
Claim 5
Dependent Claim
43 words
The method of making an opalescent body as in claim 1 which comprises dispersing said particles in molten polymethylmethacrylate or in a molten copolymer comprising at least 50 percent by weight of methyl methacrylate and then cooling to resolidify the polymer or copolymer.
Claim 6
Dependent Claim
32 words
The method as in claim 4 wherein said particles are introduced into the molten polymer or copolymer in the form of a paste comprising said particles and methyl methacrylate or a plasticizer.
Claim 7
Dependent Claim
31 words
An opalesent body as in claim 1 wherein said cross-linked polymer core is cross-linked by the presence therein of at least 0.5 percent by weight of glycol diacrylate or glycol dimethacrylate.
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) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |