Claims
- 1. A synthetic polymeric resin parison having an annular body flowed through the die of a co-extrusion head, the body comprising;
- a first substrate tube of a first synthetic polymeric resin having a high melt flow temperature within a first pre-determined range; and
- a second substrate tube of a second synthetic polymeric resin concentric with and in surface-to-surface contact with the first substrate tube, said second resin having a low melt flow temperature about 200 degrees F. less than the first predetermined range and being continuous and undegraded.
- 2. A parison as in claim 1 including a third substrate tube of a third synthetic polymeric resin concentric with the first and second tubes and having a melt flow temperature approximately equal to the melt flow temperature of the first synthetic polymeric resin, the second tube being located between said first and third tubes.
- 3. A parison as in claim 2 including a fourth substrate tube at a fourth synthetic polymeric resin concentric with the first, second and third tubes and having a low melt flow temperature approximately equal to melt flow temperature of the second tube and being continuous and undegraded, the fourth tube being located between said second and third tubes.
Parent Case Info
This application is a continuation of copending application Ser. No. 221,547 filed July 20, 1988, as a division of application Ser. No. 922,198 filed Oct. 23, 1986, as a continuation of application Ser. No. 886,734, filed July 17, 1986, now abandoned, for Modular Extrusion Head, Method, Intermediate Product and Product and Ser. No. 878,701, filed June 26, 1986, now abandoned, for Modular Extrusion Head.
US Referenced Citations (8)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0183905 |
Nov 1986 |
EPX |
2345049 |
Mar 1975 |
DEX |
Related Publications (1)
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Number |
Date |
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878701 |
Jun 1986 |
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Divisions (1)
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Number |
Date |
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Parent |
922198 |
Oct 1986 |
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Continuations (2)
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Number |
Date |
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Parent |
221547 |
Jul 1988 |
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Parent |
886734 |
Jul 1986 |
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