Patent US4874667A successfully refreshed from Google Patents.
US4874667A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microencapsulated platinum-group metals and compounds thereof
Assignee: Dow Silicones Corp
•
Filing: 1987-07-20
•
Granted: 1989-10-17
•
Expires: 2007-07-20
Abstract
Abstract Platinum-group metals and compounds thereof are microencapsulated within one or two layers of thermoplastic organic polymers. The layer or layers are deposited using known prior art microencapsulation techniques. The microcapsules can be incorporated into storage-stable one-part polyorganosiloxane compositions that cure by a platinum-catalyzed hydrosilation reaction.
Inventors
- 👤 Chi-Long Lee
- 👤 Robin L. Willis, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:20
CPC Classifications
C; C08; C08K; C08K9/00; C08K9/10; C08L; C08L83/00; C08L83/04; C08G; C08G77/00; C08G77/04; C08G77/06; C08G77/08; C08G77/12; C08G77/20; C08G77/42; C08G77/44; C08G77/70; Y; Y10; Y10S; Y10S528/00; Y10S528/901; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985; Y10T428/2987; Y10T428/2989
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
55 words
A microencapsulated liquid compound of a platinum-group metal consisting essentially of microcapsules wherein said liquid compound is completely enveloped within one or two layers of thermoplastic organic polymers, the average diameter of said microcapsules is less than 500 microns, and said thermoplastic organic polymers constitute at least 50 percent of the weight of said microcapsules.
Claim 2
Dependent Claim
55 words
A microencapsulated liquid compound of a platinum-group metal consisting essentially of microcapsules wherein said liquid compound is completely enveloped within one or two layers of thermoplastic organic polymers, the average diameter of said microcapsules is less than 500 microns, and said thermoplastic organic polymers constitute at least 50 percent of the weight of said microcapsules.
Claim 3
Dependent Claim
52 words
A microencapsulated metal or compound according to claim 1 where said thermoplastic organic polymer constitutes at least 70 percent of the microcapsule weight, and is derived from at least one ethylenically unsaturated organic compound or a condensation reaction between at least two organic compounds containing a plurality of condensable groups per molecule.
Claim 4
Dependent Claim
28 words
A microencapsulated metal or compound according to claim 2 where said thermoplastic organic polymer is formed by precipitation of a preformed polymer in the presence of said compound.
Claim 5
Dependent Claim
29 words
A microencapsulated metal or compound according to claim 2 where the thermoplastic polymer is formed in the presence of said compound in the form of a finely divided solid.
Claim 6
Dependent Claim
58 words
A microencapsulated metal or compound according to claim 1 where the encapsulated material is the reaction product of a compound comprising a platinum atom and at least one halogen atom with an organosilicon compound, and said ethylenically unsaturated organic compound is selected from the group consisting of ethylenically unsaturated hydrocarbons, acrylonitrile, and esters of acrylic or methacrylic acid.
Claim 7
Dependent Claim
25 words
A microencapsulated compound according to claim 5 where said platinum compound is hexachloroplatinic acid and said organosilicon compound contains at least one ethylenically hydrocarbon radical.
Claim 8
Dependent Claim
14 words
A microencapsulated compound according to claim 6 where said organosilicon compound is a hexaorganodisiloxane.
References Cited (Backward Citations)
US3954666A
Cited
US4105426A
Cited
US4293677A
Cited
US4460563A
Cited
US4481341A
Cited
US4421903A
Cited
US4546164A
Cited
EP0140770A2
Cited
US4528354A
Cited
US4613659A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-16 | 1993-04-17 | 1993-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-16 | 1997-04-17 | 1997-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-16 | 2001-04-17 | 2001-10-17 | $7700.00 | Window Closed / Lapsed |