Radio frequency induction heatable compositions

A method of preparing a hot-melt adhesive capable of being heated by magnetically coupled radio frequency energy comprising the steps of:

• (a) providing a non-magnetic, hot-melt adhesive particle having a surface;
• and
• (b) applying a thin, continuous, magnetic film to the surface of said adhesive particle.

A composition comprising:

• (a) a plurality of susceptors having the capability of absorbing magnetically coupled radio frequency energy, each of said susceptors comprising a non-magnetic particle having a surface bearing a thin, continuous, magnetic film capable of absorbing magnetically coupled radio frequency energy, wherein said thin, continuous, magnetic film is in direct contact with said surface of said non-magnetic particle, said susceptors disposed in
• (b) a matrix non-reflective of radio frequency energy, wherein said composition is capable of being heated when exposed to magnetically coupled radio frequency energy provided by an induction heater set at a frequency ranging from 5 to 8 MHz, said heater having a coil characterized by 5 turns of 1/4-inch outer diameter copper tubing, an inner coil diameter of 1.25 in., and a coil length of 1.75 in.

A composition comprising a plurality of susceptors having the capability of absorbing magnetically coupled radio frequency energy, each of said susceptors comprising a non-magnetic particle being granular, acicular, a plate or a flake in shape and having a surface bearing a thin, continuous, magnetic film capable of absorbing magnetically coupled radio frequency energy, wherein said thin, continuous magnetic film is in direct contact with said surface of said non-magnetic particle, said susceptors disposed in a matrix non-reflective of radio frequency energy, said matrix capable of being heated when said composition is subjected to magnetically coupled radio frequency energy.

A composition comprising a plurality of susceptors having the capability of absorbing magnetically coupled radio frequency energy, each of said susceptors comprising a non-magnetic particle having a surface bearing a thin, continuous, magnetic film capable of absorbing magnetically coupled radio frequency energy, wherein said thin, continuous magnetic film is in direct contact with said surface of said non-magnetic particle, said susceptors disposed in a matrix non-reflective of radio frequency energy, said matrix being polymeric or wax, and capable of being heated when said composition is subjected to magnetically coupled radio frequency energy.