Film
[Problem] To provide a film that has excellent water solubility which changes little over time even when the film touches a chemical, a package and a liquid transfer printing film each using the film and a liquid transfer printing method using the liquid transfer printing film. [Means for Resolution] A film containing a hydroxymethyl group-containing vinyl alcohol-based polymer containing a vinyl alcohol unit and a unit structure represented by the following formula (1), a package and a liquid transfer printing film each using the film and a liquid transfer printing method using the liquid transfer printing film.
1. A film comprising a hydroxymethyl group-containing vinyl alcohol-based polymer comprising a vinyl alcohol unit and a structural unit of formula (1)
2. The film according to claim 1 , wherein a proportion of the structural unit of formula (1) in the hydroxymethyl group-containing vinyl alcohol-based polymer is 0.1 to 30 mol %.
3. The film according to claim 1 , wherein a proportion of the structural unit of formula (1) in the hydroxymethyl group-containing vinyl alcohol-based polymer is 2 to 10 mol %.
4. The film according to claim 1 , wherein the saponification degree of the hydroxymethyl group-containing vinyl alcohol-based polymer is from 95 to 99.9 mol %.
5. The film according to claim 1 , wherein the film is a chemical packaging film.
6. The film according to claim 1 , wherein the film is a base film suitable for liquid transfer printing.
7. A package comprising a chemical packaged in the film according to claim 5 .
8. The package according to claim 7 , wherein the chemical is an agricultural chemical or a detergent.
9. A liquid transfer printing film obtained by printing on a surface of the film according to claim 6 .
10. A liquid transfer printing method, comprising:
floating the liquid transfer printing film according to claim 9 on a surface of a liquid with the printed surface facing upwards; and
pushing an object to be printed into the floating liquid transfer printing film from above.