Patent ID: 11873401
Assignee: MITSUBISHI GAS CHEMICAL COMPANY, INC.
Field: Surface technology, coating (Chemistry)
Classification: CPC B  C | IPC B  C

Claim 0:
1. An easily tearable film, which is a polyamide resin film comprising polyamide resin components comprising more than 20 parts by mass and 70 parts by mass or less of a semi-aromatic polyamide resin A and less than 80 parts by mass and 30 parts by mass or more of an aliphatic polyamide resin B, with the proviso that a sum of the semi-aromatic polyamide resin A and the aliphatic polyamide resin B is 100 parts by mass;
wherein the semi-aromatic polyamide resin A is constituted of a diamine-derived constituent unit and a dicarboxylic acid-derived constituent unit;
60 mol % or more of the diamine-derived constituent units are derived from metaxylylenediamine;
60 mol % or more of the dicarboxylic acid-derived constituent units are derived from an α,ω-linear aliphatic dicarboxylic acid having from 4 to 10 carbons;
the polyamide resin film is stretched, the polyamide resin film having an area fraction corresponding to the semi-aromatic polyamide resin A, as observed in secondary electron image observation, of 9.8% or more after plane ion milling of a cross section of the polyamide resin film in the TD direction;
wherein the semi-aromatic polyamide resin A has a molar concentration of phosphorus atoms from 0.01 to 10 a molar concentration of sodium atoms from 0.05 to 20 μmol/g, a molar concentration of potassium atoms of 20 μmol/g or less, a molar concentration of calcium atoms of 10 μmol/g or less, and a number average molecular weight from 19000 to 50000; the aliphatic polyamide resin B comprises polyamide 6; and
wherein a constituent unit including a linear alkylene chain having 5 carbons accounts for 80 mol % or more of all the constituent units of the aliphatic polyamide resin B,
wherein the easily tearable film is stretched at least in a machine direction (MD) by a factor of 3.0 to 5.0 times.