CA2913009C

Hot melt adhesive based on low melting point polypropylene homopolymers

Abstract

A hot melt adhesive for use on porous substrates, wherein the hot melt adhesive has a) about 10% to about 70%> by weight of a polypropylene homopolymer having a DSC melting point of less than 100°C; b) about 10% to about 60% of a first tackifying resin having a Ring & Ball Softening Point of about 95°C to about 140°C; c) about 0% to about 65% of a second tackifying resin that is different than the first tackifying resin; d) about 5% to about 50%> of a plasticizer; e) about 1% to about 40% by weight of a secondary polymer which is either a semi- crystalline polymer or wax with an enthalpy of fusion of greater than 30 Joules/gram; f) about 0.1% to about 5% of a stabilizer or antioxidant; wherein the components total 100% by weight of the composition, and the viscosity of the composition is equal to or less than about 20,000 centipoise (cP) at 163°C (325°F).

Term

7.7 yearsleft in the term

Expires 21 May 2034.

  1. Priority
  2. Filed
  3. Granted
  4. Today
  5. Expires

36 claims: 1 independent, 35 dependent

  1. 1
    CLAIMS:1. A hot melt adhesive for use on porous substrates, wherein the hot melt adhesive comprises: a) about 10% to about 70% by weight of a polypropylene homopolymer having a DSC melting point of less than 100° C;b) about 10% to about 60% of a first tackifying resin having a Ring & Ball Softening Point of about 95° C to about 140° C;c) about 0% to about 65% of a second tackifying resin that is different than the first tackifying resin;d) about 5% to about 50% of a plasticizer;e) about 1% to about 40% by weight of a secondary additive that is different than the plasticizer, and said secondary additive having an enthalpy of fusion of greater than 30 Joules/gram;and f) about 0.1% to about 5% of a stabilizer or antioxidant;wherein the components total 100% by weight of the composition, and the viscosity of the composition is about 20,000 centipoise (cP) at 163° C (325° F) or less than 20,000 centipoise (cP) at 163° C (325° F).