Double-sided adhesive tape having a first outer impact-adhesive side and a second outer side that can be heat activated
View Patent ↗A double-sided adhesive tape having a first outer impact-adhesive side and a second outer side that can be heat activated, comprising an at least two-layer product structure comprising the layers A and B. Layer A is an impact-adhesive layer chemically cross-linked by means of thermal initiation or an impact-adhesive carrier layer chemically cross-linked by means of thermal initiation. Layer B is a layer on the basis of a thermoplastic plastic. Layer A and layer B are in direct contact with each other, and the surface of layer B that is in direct contact with layer A has been corona- or plasma-pretreated. The double-sided adhesive tape is characterized in that the corona or plasma pretreatment is performed in an atmosphere comprising nitrogen, carbon dioxide, or a noble gas or a mixture of at least two of said gases.
1. A double-sided adhesive tape comprising an at least two-layer product system composed of layers A and B, wherein
layer A comprises a pressure-sensitive adhesive crosslinked chemically by thermal initiation, or a pressure-sensitively adhesive carrier layer crosslinked chemically by thermal initiation, and
layer B comprises a polyolefin or a polyolefin mixture, and
layer A and layer B being in direct contact with one another, and
the surface of layer B that is in direct contact with layer A having been corona- or plasma-pretreated,
and further wherein
layer A is foamed by extrusion, whereby a crosslinker system and the pressure-sensitive adhesive in a melted state are introduced together into a continuously operating mixing assembly to commence crosslinking reaction, followed by the melt being discharged from the mixing assembly and being immediately coated on layer B and shaped to form layer A,
layer A that is in contact with the corona- or plasma-pretreated surface of the layer B has been brought into contact in the chemically crosslinked state with the corona- or plasma-pretreated surface of the layer B, and
the corona or plasma pretreatment has taken place in atmosphere of nitrogen, carbon dioxide, or a noble gas, or a mixture of at least two of these gases.
2. The double-sided adhesive tape as claimed in claim 1 , wherein no additional actinic or ionizing radiation is used for crosslinking layer A.
3. The double-sided adhesive tape as claimed in claim 1 wherein layer A is a layer based on polyacrylate or polyurethane.
4. The double-sided adhesive tape as claimed in claim 3 , wherein layer A is a layer based on polyacrylate.
5. The double-sided adhesive tape as claimed in claim 1 wherein the surface of the layer A that is not in direct contact with the corona- or plasma-pretreated surface of the layer B is in direct contact with a further layer or with a further layer sequence, the outer layer of the further layer or of the further layer sequence being a layer of pressure-sensitive adhesive.
6. The double-sided adhesive tape as claimed in claim 1 wherein layer B is a layer based on a polypropylene copolymer or a mixture of a polypropylene copolymer and another polyolefin.
7. The double-sided adhesive tape as claimed in claim 1 wherein layer B has a melting temperature as determined by Differential Scanning calorimetry (DSC) of between 140° C. inclusive and 180° C. inclusive.
8. The double-sided adhesive tape as claimed in claim 1 wherein the surface of the layer A that is in contact with the corona- or plasma-pretreated surface of the layer B has been corona-pretreated in an atmosphere of air or oxygen or nitrogen or carbon dioxide or a noble gas, or a mixture of the stated gases.