Patent EP0256717A2 successfully refreshed from Google Patents.
EP0256717A2
Expired / Lapsed
EP
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Process for the manufacture of microporous film
Assignee: Rexene Products Co
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Filing: 1987-07-30
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Granted: —
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Expires: 2007-07-30
Abstract
Abstract A microporous film suitable for diaper back sheets and other disposable applications is produced by abrading an unoriented film by passing it through at least one set of at least two cooperating nip rollers, each nip roller having an abrasive grit surface.
Inventors
- 👤 Noel Lawrence Douglas
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 15:55
CPC Classifications
B; B26; B26F; B26F1/00; B24; B24B; B24B19/00; B24B19/22; B24B19/223; B29; B29C; B29C59/00; B29C59/02; B29C2059/027
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
57 words
A process for the production of a microporous film which comprises: passing an unoriented film prepared from a high molecular weight filled thermoplastic resin composition through at least one set of at least two cooperative nip rollers, each nip roller having an abrasive grit surface, and recovering an unoriented porous film as the product of the process.
Claim 2
Dependent Claim
57 words
A process for the production of a microporous film which comprises: passing an unoriented film prepared from a high molecular weight filled thermoplastic resin composition through at least one set of at least two cooperative nip rollers, each nip roller having an abrasive grit surface, and recovering an unoriented porous film as the product of the process.
Claim 3
Dependent Claim
26 words
A process according to claim 1 wherein the pressure at the nip of the rollers is between 6.9 and 69 KPa gauge (10 and 100 psig).
Claim 4
Dependent Claim
20 words
A process according to claim 1 or 2 wherein the abrasive has a grit size between 80 and 250 grain.
Claim 5
Dependent Claim
28 words
A process according to claim 1, 2 or 3 wherein the thermoplastic resin composition comprises at least one of polyethylene, linear low polyethylene, polypropylene, polybutylene and ethylene-propylene copolymers.
Claim 6
Dependent Claim
71 words
A process according to claim 4 wherein the resin comprises from 65 to 95 wt % of a low density polyethylene having a density of 0.910 to 0.935 g/cm³ and at least 5 wt % of at least one resin component selected from high density polyethylene having a density exceeding 0.940 g/cm³, a linear low density polyethylene having a density of 0.915 to 0.945 g/cm³ and a high molecular weight polybutylene.
Claim 7
Dependent Claim
24 words
A process according to claim 5 wherein the resin is a blend of the low density polyethylene, the high density polyethylene and the polybutylene.
Claim 8
Dependent Claim
49 words
A process according to any one of the preceding claims wherein the thermoplastic resin composition comprises as filler at least one of calcium carbonate, barium sulfate, mica, polytetrafluoroethylene and titanium dioxide in an amount between 5 and 25 parts by weight per 100 parts by weight of the resin.
Claim 9
Dependent Claim
20 words
A process according to claim 7 wherein the average particle size of the filler is from 3 to 30 µm.
Claim 10
Dependent Claim
35 words
A process according to any one of the preceding claims wherein the resin composition contains a whitener pigment in an amount from 3 to 16 parts by weight per 100 parts by weight of resin.
Claim 11
Dependent Claim
43 words
A process according to claim 9 wherein the thermoplastic resin composition contains from 5 to 25 parts calcium carbonate filler having an average particle size from 3 to 30 µm and from 3 to 10 parts titanium dioxide whitener per 100 parts resin.
References Cited (Backward Citations)
No citation records indexed.
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