Polyester film
US4264667A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1978 |
| Grant date | Apr 28, 1981 |
| Priority date | — |
| Expiry date | May 23, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31786
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A transparent polyester film having excellent antistatic properties, which are little effected with variation of the humidity, and further having excellent flexing resistance, pinhole resistance and printability, which is made from a mixture comprising (i) a polyester consisting essentially of a residue of dibasic acids wherein at least 80% by mol is terephthalic acid and a residue of at least one glycol and (ii) a block copolyester consisting of a crystalline polyester segment having a high melting point and a soft polymer segment having a low melting point and a number average molecular weight of 400 to 8,000, said soft polymer segment having a low melting point being contained in an amount of 0.5 to 10% by weight on the basis of the whole weight of the components (i) and (ii), and (iii) a sulfonic and/or phosphoric acid metal salt having a good heat resistance, and which is produced by melt-extruding the mixture of the components (i), (ii) and (iii), drawing at least uniaxially and then heat-treating the resultant at a temperature of 170.degree. C. or higher and lower than the melting point of the polyester (i).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.