US4933432A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of reducing dimethyl polysiloxane remaining in silicone rubber products to the ultra-micro level
Assignee: Asahi Rubber Inc
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Filing: 1988-07-19
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Granted: 1990-06-12
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Expires: 2008-07-19
Abstract
Abstract A method is provided for the reduction of the level of dimethyl polysilioxane remaining in a silicone rubber product containing said dimethyl polysiloxane to an ultra-micro level, comprising the steps of immersing the silicone rubber product in an organic solvent for the dimethyl polysiloxane and subjecting the immersed product to ultrasonic vibrations in the organic solvent.
Inventors
- 👤 Shigeyoshi Yokoyama
- 👤 Kazuhisa Takagi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:14
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/04; C08G77/32; C08G77/34; B; B01; B01D; B01D11/00; B01D11/02; B01D11/0261
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
82 words
A method of reducing the level of [(CH 3 ) 2 SiO] 3-25 remaining as an impurity and a silicone rubber product containing said [(CH 3 ) 2 SiO] 3-25 , comprising the steps of immersing said silicone rubber product in an organic liquid which is a solvent for said [(CH 3 ) 2 SiO] 3-25 but not for said rubber, subjecting the immersed product to ultrasonic vibrations in said organic solvent, and removing the immersed product from contact with said solvent.
Claim 2
Independent Claim
82 words
A method of reducing the level of [(CH 3 ) 2 SiO] 3-25 remaining as an impurity and a silicone rubber product containing said [(CH 3 ) 2 SiO] 3-25 , comprising the steps of immersing said silicone rubber product in an organic liquid which is a solvent for said [(CH 3 ) 2 SiO] 3-25 but not for said rubber, subjecting the immersed product to ultrasonic vibrations in said organic solvent, and removing the immersed product from contact with said solvent.
Claim 3
Dependent Claim
20 words
The method of claim 1, wherein said silicone rubber product is confined in a treatment reservoir during said ultrasonic treatment.
Claim 4
Dependent Claim
15 words
The method of claim 2, wherein said treatment reservoir is comprised of a mesh material.
Claim 5
Dependent Claim
32 words
The method of claim 2, wherein said treatment reservoir is hexagonal in shape and includes an opening for access to the interior of the reservoir together with means to close the opening.
Claim 6
Dependent Claim
32 words
The method of claim 2, wherein said treatment reservoir containing said silicone rubber product is rotated and subjected to reciprocating vertical movement while immersed in said organic solvent during said ultrasonic treatment.
Claim 7
Dependent Claim
31 words
The method of claim 1, wherein said silicone rubber product is subjected to infrared irradiation subsequent to removing said product from contact with said solvent thereby to remove residual solvent therefrom.
Claim 8
Dependent Claim
11 words
The method of claim 1, wherein said organic solvent is trichlorotrifluoroethane.
Claim 9
Dependent Claim
25 words
The method of claim 1, wherein said treatment in said organic solvent occurs at a temperature in the range of about 25° to 43° C.
Claim 10
Dependent Claim
28 words
The method of claim 1, wherein said silicone rubber product is treated in said organic solvent for a period of time ranging from about 10 to 60 minutes.
Claim 11
Dependent Claim
17 words
The method of claim 1, wherein said ultrasonic vibrations have frequencies ranging between 25 and 100 KHz.
Claim 12
Dependent Claim
21 words
The method of claim 6, wherein the treatment temperature ranges from about 40° to 100° C. during said infrared heating treatment.
Claim 13
Dependent Claim
20 words
The method of claim 6, wherein said infrared treatment occurs over a period of time between 20 and 60 minutes.
Claim 14
Dependent Claim
27 words
The method of claim 2, wherein said treatment reservoir containing said silicone rubber product is preheated by means of infrared irradiation prior to contact with said solvent.
Claim 15
Dependent Claim
19 words
The method of claim 13, wherein the temperature during said preheating step ranges from about 180° to 200° C.
Claim 16
Dependent Claim
30 words
The method of claim 1, wherein said silicone rubber product subsequent to treatment with said solvent is washed with a further quantity of said organic solvent and dried with air.
Claim 17
Dependent Claim
20 words
The method of claim 15, wherein said silicone rubber product is dried with air for a period of 10 minutes.
Claim 18
Dependent Claim
25 words
The method of claim 1, wherein said organic solvent is selected from the group consisting of carbon tetrachloride, n-hexane, 1,1,1-trichloroethane, methylene chloride, chloroform and trichlorotrifluoroethane.
Claim 19
Dependent Claim
22 words
The method of claim 6, wherein said silicone rubber product is subjected to multiple infrared irradiation treatments to remove residual solvent therefrom.
Claim 20
Dependent Claim
26 words
The method of claim 18, wherein residual solvent removed from said product by said infrared irradiation treatments is recovered for use in said solvent treatment step.
References Cited (Backward Citations)
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