Heat-activable adhesive tape particularly for bonding electronic components and conductor tracks

1. Heat-activable adhesive tape with an adhesive composed at least of

a) an acid-modified or acid anhydride-modified vinylaromatic block copolymer,

b) an epoxide-containing compound and,

c) a metal chelate as crosslinker,

said adhesive being crosslinkable in two separate crosslinking steps, one at room temperature and the second at a temperature above 150° C.

2. Heat-activable adhesive tape according to claim 1 , wherein the vinylaromatic block copolymer is a styrene block copolymer.

3. Heat-activable adhesive tape according to claim 1 wherein the epoxide-containing compound is an epoxy resin, an epoxidized polymer or a combination thereof.

4. Heat-activable adhesive tape according to claim 1 , wherein in the second crosslinking step the epoxide groups crosslink with the acid or acid anhydride groups of the vinylaromatic block copolymer.

5. Heat-activable adhesive tape according to claim 1 , wherein the metal chelate is represented by the formula

(R 1 O) n M(XR 2 Y) m ,

where

M is a metal from main group 2, 3, 4 or 5, or a transition metal,

R 1 is an alkyl or aryl group,

n is zero or a larger integer,

X and Y are oxygen or nitrogen, which in each case may also be attached to R 2 by a double bond,

R 2 is an alkylene group which connects X and Y and which may be branched, or else may contain oxygen or further heteroatoms,

m is an integer, but is at least 1.

6. Heat-activable adhesive tape according to claim 1 , wherein the metal chelate is aluminium acetylacetonate or titanyl acetylacetonate.

7. Heat-activable adhesive tape according to claim 1 , wherein the adhesive tape comprises further acid anhydrides, further elastomers, tackifying resins, accelerators, dyes, carbon black, metal powders or combinations thereof.

8. Heat-activable adhesive tape according to claim 1 , wherein said acid-modified or acid anhydride-modified vinylaromatic block copolymer and said epoxide-containing compound are present in amounts whereby the amount of said epoxide-containing compound present is not more than 10% by weight of the amount of acid-modified or acid anhydride-modified elastomer present.

9. Method of adhesively bonding plastic parts, wherein said plastic parts are bonded with the heat-activable adhesive tape of claim 1 , having an adhesive comprising at least the acid-modified or acid anhydride-modified vinylaromatic block copolymer and an epoxy resin as the epoxide-containing compound.

10. A method for bonding plastic parts which comprises bonding said plastic parts with the heat-activable adhesive tape of claim 1 .

11. Method for bonding electronic components and/or flexible printed circuits (FPCBs) which comprises bonding said electronic components and/or flexible printed circuits with the heat-activable adhesive tape of claim 1 .

12. Method for bonding an object to polyimide which comprises bonding said object to polyimide with the heat-activable adhesive tape of claim 1 .