Manufacturing method for oriented film, polarizing film, polarizing plate, and visual display

摘要

An oriented film of polyvinyl alcohol derived film that demonstrates a small dimensional change under a heated or humidified condition is obtained by a manufacturing method for an oriented film comprising the steps of; stretching in two to six times a non-stretched filmwith moisturepercentage adjusted to no more than 10% comprising polyvinyl alcohols or derivatives by heating at no less than 70° C.; and subsequently annealing by heating again at no less than 70° C. after once cooling at no more than 40° C.