Polyvinyl acetal resin film and multilayer structure articles using the same

摘要

An object of the present invention is to provide a film that is used as one layer of a multilayer structure articles such as a laminated glass, and a solar cell module, and prevents the intrusion of bubbles and the generation of unfilled portions at the edge portions of the film; and a multilayer structure articles obtained with the use of the film. A polyvinyl acetal resin film, having a thickness distribution in the width direction of 10% or less, and a volatile matter content of 1.0 mass % or less, in which as to a portion of 5% of the total width inside from each of both edges in the width direction, when each portion is heated at 150° C. for 30 minutes, the larger value of the heat shrinkage in the flow direction that is parallel to the film and perpendicular to the width direction is referred to as heat shrinkage MD1, and the other value is referred to as heat shrinkage MD2, and when central portion in the width direction of the film is heated at 150° C. for 30 minutes, the heat shrinkage in the flow direction that is parallel to the film and perpendicular to the width direction is referred to as heat shrinkage MD3, all the heat shrinkage MD1, heat shrinkage MD2, and heat shrinkage MD3 are 3 to 20%.

主权项

1. A polyvinyl acetal resin film, comprising:
a thickness distribution in a width direction of 10% or less, wherein heat shrinkages MD1, MD2 and MD3 are independently from 3% to 20% when the polyvinyl acetal resin film is heated at 150° C. for 30 minutes, wherein the heat shrinkage MD1 is a heat shrinkage in a flow direction of the polyvinyl acetal resin film at a first edge portion, the heat shrinkage MD2 is a heat shrinkage in the flow direction at a second edge portion, the heat shrinkage MD3 is a heat shrinkage in the flow direction at a central portion, and wherein the heat shrinkage MD1 is larger than the heat shrinkage MD 2, and an edge portion is defined by a portion of 5% of a total width of the polyvinyl acetal resin film inside from an edge in the width direction, and the flow direction is parallel to the polyvinyl acetal resin film and perpendicular to the width direction.