Polypropylene resin composition, T die film made of the same and method of producing T die film
US6512050B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2001 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Jun 28, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31938
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A polypropylene resin composition comprising 100 parts by weight of a polypropylene resin (A) having a die swell ratio of less than about 1.70 and about 0.01 to about 45 parts by weight of a polypropylene resin (B) having a die swell ratio of about 1.80 or more. A T die film is also provided, composing polypropylene wherein the film has a molecular weight distribution of about 4.2 or less and a die swell ratio of 1.28 or more. A method of producing a T die film is also provided, comprising the steps of melt-kneading polypropylene by an extruder, extruding the melted product through a die lip, and cool-solidifying the extruded material by a cooling roll to form a film. The film resulting by this method has a molecular weight distribution about of 4.2 or less and a die swell ratio of about 1.28 or more. Further, the present invention provides a laminated molded body comprising a heat molded body composed of a polypropylene resin composition containing 100 parts by weight of polypropylene resin (A), about 0.01 to about 45 parts by weight of a polypropylene resin (B) and a substrate comprising a thermoplastic resin.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.