Patent US5092479A successfully refreshed from Google Patents.
EP0155337A2
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Method and apparatus for manufacturing porous polytetrafluoroethylene material
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1984-03-27
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Granted: —
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Expires: 2004-03-27
Abstract
Abstract method for manufacturing a porous polytetrafluoroethylene material comprising extruding or rolling or a process consisting of the both an unsintered polytetrafluoroethylene mixture containing a liquid lubricant, and carrying out simultaneously next four steps of a) evaporating a liquid lubricant, b) stretching the molded articles in an unsintered condition, c) sintering the same in a stretched condition, and d) stretching the same in a sintered condition at an atmospheric temperature of more than 390°C to obtain mechanical strengths such as a Young's modulus of more than 10000 kg/cm 2 , and a matrix tensile strength of more than 1100 kg/ cm 2 .
Inventors
- 👤 Koichi C/O Osaka Works Okita
- 👤 Shinichi C/O Osaka Works Toyooka
- 👤 Shigeru C/O Osaka Works Asako
- 👤 Katsuya C/O Osaka Works Yamada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 03:56
CPC Classifications
B; B29; B29C; B29C55/00; B29C55/005; B29C67/00; B29C67/20; B29C67/202; B29D; B29D23/00; B29D7/00; B29K; B29K2027/00; B29K2027/12; B29K2027/18; B29K2105/00; B29K2105/04
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
104 words
A method for manufacturing a porous polytetrafluoroethylene material comprising extruding or rolling or a process consisting of the both an unsintered polytetrafluoroethylene mixture containing a liquid lubricant, and carrying out simultaneously next four steps of a) evaporating a liquid lubricant, b) stretching the molded articles in an unsintered condition, c) sintering the same in a stretched condition, and d) stretching the same in a sintered condition at an atmospheric temperature of more than 390°C to obtain mechanical strengths such as a Young's modulus of more than 10000 kg/cm 2 , and a matrix tensile strength of more than 1100 kg/ c m 2 .
Claim 2
Independent Claim
104 words
A method for manufacturing a porous polytetrafluoroethylene material comprising extruding or rolling or a process consisting of the both an unsintered polytetrafluoroethylene mixture containing a liquid lubricant, and carrying out simultaneously next four steps of a) evaporating a liquid lubricant, b) stretching the molded articles in an unsintered condition, c) sintering the same in a stretched condition, and d) stretching the same in a sintered condition at an atmospheric temperature of more than 390°C to obtain mechanical strengths such as a Young's modulus of more than 10000 kg/cm 2 , and a matrix tensile strength of more than 1100 kg/ c m 2 .
Claim 3
Dependent Claim
82 words
A method of manufacturing a polytetrafluoroethylene porous material as described in Claim 1,characterized in that control of an atmospheric temperature at which four steps of evaporating the lubricant, stretching the molded articles in an unsintered conditiion, sintering the same in a stretched condition, and stretching the same in a sintered condition are simultaneously carried out, is made by a circulating hot air oven at wind velocity of more than 5 m/sec., and that the evaporated lubricant is burnt by an oxidizing catalyst.
Claim 4
Dependent Claim
30 words
A method of manufacturing a polyetetrafluoroethylene porous material as described in Claim 1, characterized in that a molded articles is in either form of a film, tube or a rod.
Claim 5
Dependent Claim
26 words
A method of manufacturing a polytetrafluoroethylene porous material as described in Claim 1, characterized in that a boiling range of the lubricant is less than 260°C.
Claim 6
Dependent Claim
68 words
A method of manufacturing a porous polytetrafluoroethylene material as described in Claim 1, characterized in that the atmospheric temperature at which four steps of evaporating the lubricant, stretchinq the molded articles in an unsintered condition, sinterina the same in a stretched condition, and stretching the same in a sintered condition are simultaneously carried out, is more than 450°C, and that a furnace temperature distribution is less than 30°C.
Claim 7
Dependent Claim
68 words
A method of manufacturing a porous polytetrafluoroethylene material as described in Claim 1, characterized in that the atmospheric temperature at which four steps of evaporating the lubricant, sintering the molded articles in an unsintered conditions, sintering the same in a stretched condition, and stretching the same in a sintered condition are simultaneously carried out, is more than 500°C, and that a furnace temperature distribution is less than 30°C.
Claim 8
Independent Claim
176 words
An apparatus of manufacturing a porous polytetrafluoroethylene porous material from an unsintered polytetrafluroroethvlene containing a liauid lubricant which is subjected to four steps, simultaneouslv carried out, of evaporating the lubricant, stretching the molded material in an unsintered condition, sinterinq the same in a stretched condition, and stretching the same in a sintered condition, said apparatus comprising a hot furnace including a double cylinder piped furnace of an inner cylinder part through which a molded material passes and an outer cylinder portion in which a heater is incorporated, said two cylinder parts being coupled to'one another by the both ends thereof, means for circulating a hor air through said two cylinder parts, means for detecting a furnace temperature, means for adjusting an inflow of the air at an inlet and an outlet of the furnace, means for forcibly exhausting a portion of the furnace hot air, a catalyst for facilitating oxidization of the vaporized lubricant, and means for supplying the molded article to the furnace, and take-up means actuated at a speed more than such supply speed.
Claim 9
Independent Claim
176 words
An apparatus of manufacturing a porous polytetrafluoroethylene porous material from an unsintered polytetrafluroroethvlene containing a liauid lubricant which is subjected to four steps, simultaneouslv carried out, of evaporating the lubricant, stretching the molded material in an unsintered condition, sinterinq the same in a stretched condition, and stretching the same in a sintered condition, said apparatus comprising a hot furnace including a double cylinder piped furnace of an inner cylinder part through which a molded material passes and an outer cylinder portion in which a heater is incorporated, said two cylinder parts being coupled to'one another by the both ends thereof, means for circulating a hor air through said two cylinder parts, means for detecting a furnace temperature, means for adjusting an inflow of the air at an inlet and an outlet of the furnace, means for forcibly exhausting a portion of the furnace hot air, a catalyst for facilitating oxidization of the vaporized lubricant, and means for supplying the molded article to the furnace, and take-up means actuated at a speed more than such supply speed.
References Cited (Backward Citations)
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