Masking pressure-sensitive adhesive tape

Abstract

Provided is a masking pressure-sensitive adhesive tape to be used in formation of a metal layer by a vacuum film formation method on part of a surface of an electronic part, which may prevent formation of a metal layer, by the vacuum film formation method, on a surface masked by the masking pressure-sensitive adhesive tape. The masking pressure-sensitive adhesive tape includes: a base material; and a pressure-sensitive adhesive layer arranged on one side of the base material, in which the pressure-sensitive adhesive layer has a thickness of 5 μm or more, and the masking pressure-sensitive adhesive tape has a 180° peeling adhesive strength at 23° C. with respect to a stainless-steel plate of 0.4 N/20 mm or more.

What is claimed is: 
     
         1 . A masking pressure-sensitive adhesive tape to be used in formation of a metal layer by a vacuum film formation method on part of a surface of an electronic part,
 the masking pressure-sensitive adhesive tape comprising:   a base material; and   a pressure-sensitive adhesive layer arranged on one side of the base material,   wherein the pressure-sensitive adhesive layer has a thickness of 5 μm or more,   wherein the pressure-sensitive adhesive layer is formed of an acrylic pressure-sensitive adhesive and   wherein the masking pressure-sensitive adhesive tape has a 180° peeling adhesive strength at 23° C. with respect to a stainless-steel plate of 0.4 N/20 mm or more.   
     
     
         2 . The masking pressure-sensitive adhesive tape according to  claim 1 , wherein the masking pressure-sensitive adhesive tape has a 180° peeling adhesive strength at 23° C. with respect to a stainless-steel plate of 10 N/20 mm or less after the masking pressure-sensitive adhesive tape is bonded onto the stainless-steel plate and left to stand at 200° C. for 1 hour. 
     
     
         3 . The masking pressure-sensitive adhesive tape according to  claim 1 ,
 wherein a 5% weight loss temperature of the pressure-sensitive adhesive layer is 250° C. or more, and   wherein the 5% weight loss temperature is a temperature at the time when the weight of the pressure-sensitive adhesive layer is reduced by 5% with respect to an initial weight in thermogravimetric (TG) measurement under the following conditions;   
       (TG measurement conditions) 
       Measurement temperature range: from room temperature to 850° C. 
       Temperature rising rate: 10° C./min 
       Atmospheric gas: atmosphere 
       Gas flow rate: 200 ml/min. 
     
     
         4 . The masking pressure-sensitive adhesive tape according to  claim 1 , wherein the base material formed of a polyether sulfone-based resin, a polyether imide-based resin, a polysulfone-based resin, a polyether ether ketone-based resin, a polyarylate-based resin, an aramid-based resin, or a polyimide-based resin.