Sealing tape for adhesive bonding of vapour barrier films and vapour retarder films, and process for its manufacture

Abstract

Self-adhesive, flexible sealing tapes, comprising at least one flexible, self-adhesive core or at least one flexible, self-adhesive carrier layer provided with an envelope or two-sided coating consisting of a second adhesive system.

1 . A process for manufacturing a self-adhesive, flexible sealing tape comprising at least one flexible, self-adhesive core/carrier layer provided with an envelope/two-sided coating which comprises a pressure-sensitive adhesive tape containing an expanded pressure-sensitive adhesive, said process comprising the steps of:
 manufacturing said at least one core/carrier layer and the envelope/two-sided coating by independent processes as web-like materials;   subsequently advancing two pre-fabricated pressure-sensitive adhesive tapes containing said expanded pressure-sensitive adhesive, one per side, towards a web consisting of an elastic core material/carrier layer material; and   applying pressure to combine said pre-fabricated pressure-sensitive adhesive tapes with said web consisting of the elastic core material/carrier layer material.   
   
   
       2 . The process according to  claim 1 , wherein the process for manufacturing said pre-fabricated pressure-sensitive adhesive tapes comprises the steps of:
 producing an aqueous dispersion of a pressure-sensitive adhesive containing a filler consisting of small, thermoplastic hollow plastic spheres which are filled with hydrocarbon gas, said hollow spheres being expandable upon exposure to a temperature in the range between 70° C. and 140° C.;   processing the aqueous dispersion to a pressure-sensitive adhesive tape; and   expanding said adhesive tape.   
   
   
       3 . The process according to  claim 1 , wherein the material for the at least one core/carrier layer is selected from the group consisting of thermoplastic rubbers on the basis of styrene-isoprene-styrene block copolymers, styrene-butadiene-styrene block copolymers, copolymers of vinyl acetate, polyisobutylenes and acrylates which have been cross-linked by a process selected from the group consisting of thermal irradiation and UV irradiation. 
   
   
       4 . The process according to  claim 1 , wherein the material for the at least one core/carrier layer has a glass transition temperature (Tg) of below 0° C. 
   
   
       5 . The process according to  claim 1 , wherein the pressure-sensitive adhesive tape is based on a pure dispersion acrylate. 
   
   
       6 . The process according to  claim 5 , wherein the pure dispersion acrylate is based on plasticizing monomers selected from the group consisting of 2-ethylhexyl acrylate, 1-butyl acrylate and n-butyl acrylate. 
   
   
       7 . The process according to  claim 1 , wherein the pressure-sensitive adhesive tape comprises an adhesive based on a material selected from the group consisting of vinyl isobutyl ether and isobutene. 
   
   
       8 . The process according to  claim 1 , wherein the thickness of the at least one core/carrier layer is between 0.1 mm and 8 mm. 
   
   
       9 . The process according to  claim 1 , wherein the width of the at least one core/carrier layer is between 1 mm and 10 mm. 
   
   
       10 . The process according to  claim 9 , wherein the width of the at least one core/carrier layer is between 1 mm and 5 mm. 
   
   
       11 . The process according to  claim 1 , wherein the thickness of the envelope/coating is between 0.2 and 1.5 mm. 
   
   
       12 . The process according to  claim 11 , wherein the thickness of the envelope/coating is between 0.5 and 1 mm. 
   
   
       13 . The process according to  claim 1 , wherein the envelope/coating has a foam-like structure. 
   
   
       14 . The process according to  claim 1 , further comprising a step of providing the sealing tape with reinforcing elements for stabilising the sealing tape. 
   
   
       15 . The process according to  claim 14 , wherein said reinforcing elements stabilise the sealing tape in a longitudinal direction. 
   
   
       16 . The process according to  claim 14 , wherein said reinforcing elements are selected from the group consisting of threads, nonwovens or interlaid scrims, wovens, knitted fabrics and crocheted fabrics. 
   
   
       17 . The process according to  claim 1 , wherein said at least one core/carrier layer is inserted as an intermediate layer between said two pre-fabricated expanded pressure-sensitive adhesive tapes. 
   
   
       18 . The process according to  claim 1 , wherein the core is enveloped by said pre-fabricated expanded pressure-sensitive adhesive tapes. 
   
   
       19 . The process according to  claim 1 , wherein said sealing tape comprises two flexible, self-adhesive core/carrier layers. 
   
   
       20 . The process according to  claim 1 , further comprising the step of folding the core/carrier layer material. 
   
   
       21 . The process according to  claim 1 , wherein the at least one core/carrier layer is formed comprising a shape selected from the group consisting of a round cross-sectional shape and an oval cross-sectional shape. 
   
   
       22 . The process according to  claim 1 , wherein the at least one core/carrier layer is formed comprising a shape selected from the group consisting of a rectangular cross-sectional shape and a square cross-sectional shape.