Oriented polyolefin film

• US 4,234,664 A
• Filed: 03/30/1979
• Issued: 11/18/1980
• Est. Priority Date: 02/06/1976
• Status: Expired due to Term

• Current Assignee: Imperial Chemical Industries Limited (Nouryon BV)
• Original Assignee: Imperial Chemical Industries Limited (Nouryon BV)
• Inventors: Hendy, Brian N.
• Primary Examiner(s): McCamish, Marion
• Assistant Examiner(s): Buffalow, E. Rollins
• Application Number:
  US06/025,599
• Time in Patent Office: 599 Days
• Field of Search: 428/910, 428/516, 252/88, 252/8.75
• US Class Current: 428/520
• CPC Class Codes: C08J 2323/02 not modified by chemical after treatment
• CPC Class Codes: C08J 7/044 Forming conductive coatings; Forming coatings having anti-static properties
• CPC Class Codes: C08J 7/065 Low-molecular-weight organic substances, e.g. absorption of additives in the surface of the article
• CPC Class Codes: Y10S 428/91 Product with molecular orientation
• CPC Class Codes: Y10T 428/31855 Of addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31913 Monoolefin polymer
• CPC Class Codes: Y10T 428/31928 Ester, halide or nitrile of addition polymer

Abstract

Oriented polyolefin (especially polypropylene) film having antistatic properties is produced by applying to the cast extrudate an aqueous solution of an `Ethoquad` salt (e.g. `Ethoquad` C/12) before heating and stretching the extrudate to orient it. The corresponding tertiary amine chlorides (e.g. prepared from `Ethomeen` T/12) are not effective.

Claims

1. An oriented polyolefin film comprising a polyolefin substrate having on at least one surface thereof a mixture comprising:

(a) a quaternary ammonium salt of the formula;

##STR3## wherein X is a univalent anion or an equivalent of a multivalent anion, x and y are positive integers the sum of which is from 2 to 5, A is a lower alkyl group containing from 1 to 6 carbon atoms, and R is a univalent aliphatic radical containing from 1 to 22 carbon atoms, and (b) a monoethoxylated quaternary ammonium salt.

2. A film according to claim 1 wherein the quaternary ammonium salts (a) and (b) are present on the surface in an amount sufficient to yield a surface resistivity not exceeding 10 gigohms at 50% relative humidity.

3. A film according to claim 1 wherein R in the formula of the quaternary ammonium salt is a coconut oil residue and is predominantly composed of dodecyl radicals.

4. A film according to claim 1 wherein R in the formula of the quaternary ammonium salt is derived from oleine and is predominantly composed of oleyl radicals.

5. A film according to claim 1 wherein X is chlorine, the sum of x and y is 2, and A is a methyl group.

6. A film according to claim 1 wherein the salt of (b) is choline chloride.

7. A film according to claim 1 wherein the substrate comprises a substantially crystalline polymer of propylene.

8. A film according to claim 1 wherein the substrate is a multiple-layer substrate having a propylene layer and at least one surface layer of a copolymer of propylene with from 5 to 20% by weight of the copolymer of another alpha-olefin containing from 4 to 10 carbon atoms in its molecule.