Patent EP0259003A2 successfully refreshed from Google Patents.
EP0259003A2
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 first abrading an unoriented film by passing it through at least one set of at least two cooperating nip rollers, at least one nip roller having an abrasive grit surface, and then subjecting the abraded film to a corona treatment.
Inventors
- 👤 Noel Lawrence Douglas
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 17:05
CPC Classifications
B; B29; B29C; B29C67/00; B29C67/20; B29C59/00; B29C59/02; B29C59/04; B29C59/10; B29C2059/027; B29K; B29K2105/00; B29K2105/04; B29K2105/06; B29K2105/16; B29L; B29L2031/00; B29L2031/48; B29L2031/4871; B29L2031/4878
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
70 words
A process for the production of a microporous film which comprises passing an unoriented film prepared from a high molecular weight thermoplastic resin composition through at least one set of at least two cooperating nip rollers, at least one nip roller being provided with an abrasive surface, subjecting the abraded film to a corona discharge treatment between two electrodes, and recovering the microporous film directly after the corona discharge treatment.
Claim 2
Dependent Claim
70 words
A process for the production of a microporous film which comprises passing an unoriented film prepared from a high molecular weight thermoplastic resin composition through at least one set of at least two cooperating nip rollers, at least one nip roller being provided with an abrasive surface, subjecting the abraded film to a corona discharge treatment between two electrodes, and recovering the microporous film directly after the corona discharge treatment.
Claim 3
Dependent Claim
27 words
A process according to claim 1 wherein the abraded film prior to corona discharge treatment had a moisture vapor transmission rate of at least 100 g/m²/24 h.
Claim 4
Dependent Claim
28 words
A process according to claim 1 or 2 wherein the pressure at the nip of the rollers is between 6.9 and 69 KPa gauge (10 and 100 psig).
Claim 5
Dependent Claim
21 words
A process according to claim 1, 2 or 3 wherein the abrasive has a grit size between 80 and 250 grain.
Claim 6
Dependent Claim
27 words
A process according to any one of the preceding claims wherein the potential between the electrodes is maintained during corona discharge treatment between 3000 and 5000 volts.
Claim 7
Dependent Claim
26 words
A process according to any one of the preceding claims wherein the corona discharge treatment is carried out using a current between 0.35 and 5 amperes.
Claim 8
Dependent Claim
26 words
A process according to any one of the preceding claims wherein the corona discharge treatment is carried out at a frequency between 50 and 60 KHz.
Claim 9
Dependent Claim
29 words
A process according to any one of the preceding claims wherein the thermoplastic resin composition comprises at least one of polyethylene, linear low polyethylene, polypropylene, polybutylene and ethylenepropylene copolymers.
Claim 10
Dependent Claim
71 words
A process according to claim 8 wherein the resin comprises from 65 to 95 wt % of a low density polyethylene having a density of 0.910 to 0.935 gm/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 11
Dependent Claim
48 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 amount between 5 and 25 parts by weight per 100 parts by weight of the resin.
Claim 12
Dependent Claim
20 words
A process according to claim 10 wherein the average particle size of the filler is from 3 to 30 µm.
Claim 13
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.
References Cited (Backward Citations)
No citation records indexed.
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