Pressure-sensitive adhesive for pressure-sensitive adhesive layer in volume hologram laminate
申请人:Dai Nippon Printing Co., Ltd.
公开号:US20030068491A1
公开(公告)日:2003-04-10
A pressure-sensitive adhesive for a pressure-sensitive adhesive layer in a volume hologram laminate is provided which, when kept in the pressed state, for example, during storage, is less likely to cause spotty hologram defects in the volume hologram layer. The pressure-sensitive adhesive for a pressure-sensitive adhesive layer in a volume hologram laminate is a pressure-sensitive adhesive for a pressure-sensitive adhesive layer in a volume hologram laminate comprising a substrate
2
and, stacked on the substrate
2
in the following order, a first pressure-sensitive adhesive layer
3,
a volume hologram layer
5,
a second pressure-sensitive adhesive layer
4,
and a surface protective film
6,
the second pressure-sensitive adhesive layer having been formed from an acrylic pressure-sensitive adhesive comprising an acrylic copolymer resin, composed mainly of an alkyl acrylate, and a crosslinking agent, the second pressure-sensitive adhesive layer having a dynamic storage modulus of not less than 2.5×105 Pa as measured at a measuring frequency of 6.28 rad/sec and a temperature of 50° C. and a loss tangent (tan &dgr;) defined as dynamic loss modulus/dynamic storage modulus at 120° C. of not more than 0.15.
本发明提供了一种用于体积全息图层压板中压敏胶层的压敏胶,当保持压敏状态(例如在储存期间)时,不易在体积全息图层中产生斑点状全息图缺陷。用于体积全息图层压板中压敏粘合层的压敏粘合剂是一种用于体积全息图层压板中压敏粘合层的压敏粘合剂,包括基板
2
和堆叠在基板上的
2
第一压敏胶层
3,
体积全息图层
5,
第二压敏胶层
4,
和表面保护膜
6,
第二压敏胶层由丙烯酸压敏胶形成,该丙烯酸压敏胶由主要由丙烯酸烷基酯组成的丙烯酸共聚物树脂和交联剂组成,第二压敏胶层的动态存储模量不小于 2.5×105 Pa,该动态存储模量是在 6.28 弧度/秒的测量频率和 50 摄氏度的温度下测得的,损耗正切(tan &dgr;)定义为 120 摄氏度时的动态损耗模量/动态存储模量,不大于 0.15。