Heat-sealable films
    4.
    发明申请
    Heat-sealable films 审中-公开
    热封膜

    公开(公告)号:US20050100752A1

    公开(公告)日:2005-05-12

    申请号:US10602197

    申请日:2003-06-24

    申请人: Aiko Hanyu Ben Hicks

    发明人: Aiko Hanyu Ben Hicks

    IPC分类号: B32B7/10 B32B27/32 B32B27/08

    摘要: A multilayer polyolefin film of the type suitable for packaging application in which heat seals are formed, and in its preparation the multilayer film comprises a flexible substrate layer formed of a crystalline thermoplastic polymer having an interface surface. A heat-sealable surface layer is bonded to the interface surface of the substrate layer and is formed of a syndiotactic propylene polymer effective to produce a heat seal with itself at a sealing temperature of less than 110° C. The surface layer has a thickness which is less than the thickness of the substrate layer. The heat-seal layer can be formed of syndiotactic polypropylene polymerized in the presence of a syndiospecific metallocene catalyst and having a melt flow index of less than 2 grams/10 minutes. The multilayer film can take the form of a biaxially-oriented film. In the production of the multilayer film incorporating a substrate layer and a heat-sealable surface layer, a crystalline thermoplastic polymer is extruded and formed into a substrate layer film. A second polymer comprising a syndiotactic propylene polymer which is effective to form a heat-sealable surface layer is extruded to form a surface layer that is bonded to the interface of the substrate layer at a temperature within the range of 150-260° C.

    摘要翻译: 一种适用于其中形成热封的包装应用的多层聚烯烃薄膜,在其制备中,多层薄膜包括由具有界面表面的结晶热塑性聚合物形成的柔性基底层。 可热封的表面层粘合到基底层的界面,并由间同立构丙烯聚合物形成,该聚合物有效地在小于110℃的密封温度下自身产生热封。表面层的厚度 小于衬底层的厚度。 热密封层可以由间同立构聚丙烯在间同立构茂金属催化剂存在下聚合并且具有小于2克/ 10分钟的熔体流动指数形成。 多层膜可以采用双轴取向膜的形式。 在制造包含基材层和可热封表面层的多层膜时,将结晶性热塑性聚合物挤出并形成基材层膜。 挤出含有有效形成可热封表面层的间同立构丙烯聚合物的第二聚合物,以形成在150-260℃的温度范围内与基材层的界面结合的表面层。