Hot melt adhesive with high peel and shear strengths for nonwoven applications

• US 6,218,457 B1
• Filed: 03/03/1999
• Issued: 04/17/2001
• Est. Priority Date: 04/30/1997
• Status: Expired due to Term

• Current Assignee: ATO Findley Incorporated
• Original Assignee: ATO Findley Incorporated
• Inventors: Fralich, Margaret M., Alper, Mark
• Primary Examiner(s): YOON, TAE H
• Application Number:
  US09/261,357
• Time in Patent Office: 776 Days
• Field of Search: 524/270, 524/271, 524/487, 524/515, 524/489, 524/484, 524/477, 525/240
• US Class Current: 524/489
• CPC Class Codes: C08L 23/02 not modified by chemical after-treatment
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 57/02 Copolymers of mineral oil hydrocarbons
• CPC Class Codes: C08L 91/06 Waxes
• CPC Class Codes: C09J 123/20 having four to nine carbon atoms

Abstract

A polybutylene based hot melt adhesive composition having a variety of end uses, particularly in construction and elastic attachment applications for nonwoven articles such as disposable diapers. Unlike typical hot melt adhesives, the present composition can withstand high peel and shear loads at elevated temperatures for extended periods of time without experiencing catastrophic bond failure. The composition includes polybutylene polymer or a mixture of polybutylene and polyolefin polymers, and a stabilizer, with the remaining ingredients chosen from one or more of a polyolefin polymer, a tackifier resin, a plasticizer, or a wax. The hot melt adhesive composition can be applied using common application techniques such as extruding or spraying.

Claims

1. A high peel and shear strength hot melt adhesive composition consisting essentially of a blend of:

(a) about 15% to about 65% by weight of a polybutylene polymer, said polybutylene polymer selected from the group consisting of polybutylene homopolymer, polybutylene copolymer, and blends of polybutylene homopolymer and copolymer;

(b) about 0.1% to about 3% by weight of a stabilizer; and

(c) about 5% to about 20% by weight of a polypropylene wax having a softening point of 200°

F. to 350°

F.;

the remaining ingredients chosen from one or more of the following components so that the ingredients add up to 100% by weight based on the weight of the entire composition;

(d) about 0% to about 60% by weight of a hydrocarbon tackifying resin, said tackifying resin is selected from the group consisting of aliphatic hydrocarbon resins, hydrogenated aromatic hydrocarbon resins, hydrogenated aliphatic hydrocarbon resins and hydrogenated aromatic/aliphatic hydrocarbon resins; and

(e) about 0% to about 30% by weight of a plasticizer selected from the group consisting of mineral oil, and polybutene having a molecular weight of 2000 or less;

and wherein the minimum polybutylene polymer content is 15% by weight;

and wherein the adhesive composition has a viscosity of less than 25,000 cP at 350°

F. and a melt point higher than 250°

F., and withstands a peel mode force of 500 grams at 100°

F. for a minimum of about 11 hours and further withstands a shear mode force of 1000 grams at 100°

F. for a minimum of about 11 hours.

2. A hot melt adhesive composition as claimed in claim 1 wherein said polybutylene polymer is a poly(butylene-ethylene) copolymer.

3. A high peel and shear strength hot melt adhesive composition, consisting of:

(a) about 65% by weight of a polybutylene polymer, said polybutylene polymer selected from the group consisting of polybutylene homopolymer, polybutylene copolymer, and blends of polybutylene homopolymer and copolymer;

(b) about 19.5% by weight of a polypropylene wax having a softening point of 200°

F. to 350°

F.

(c) about 15% by weight of a plasticizer wherein said plasticizer is selected from the group consisting of mineral oil, and a polybutene having a molecular weight of 2,000 or less;

(d) about 0.5% by weight of a stabilizer; and

(e) wherein the adhesive composition has a viscosity of less than 25,000 cP at 350°

F. and a melt point higher than 250°

F., and withstands a peel mode force of 500 grams at 100°

F. for a minimum of about 11 hours and further withstands a shear mode force of 1000 grams at 100°

F. for a minimum of about 11 hours.

4. A hot melt adhesive composition as claimed in claim 3 wherein said polybutylene polymer is a poly(butylene-ethylene) copolymer.

5. A high peel and shear strength hot melt adhesive composition, consisting essentially of:

(a) about 50% by weight of a polybutylene polymer, said polybutylene polymer selected from the group consisting of polybutylene homopolymer, polybutylene copolymer, and blends of polybutylene homopolymer and copolymer;

(b) about 15% by weight of a plasticizer selected from the group consisting of mineral oil and polybutene having a molecular weight of 2000 or less;

(c) about 15% by weight of a hydrocarbon tackifying resin, said tackifying resin is selected from the group consisting of aliphatic hydrocarbon resins, hydrogenated aromatic hydrocarbon resins, hydrogenated aliphatic hydrocarbon resins and hydrogenated aromatic/aliphatic hydrocarbon resins;

(d) about 19.5% by weight of a polypropylene wax having a softening point of 200°

F. to 350°

F.;

(e) about 0.5% by weight of a stabilizer; and

(f) wherein the adhesive composition has a viscosity of less than 25,000 cP at 350°

F. and a melt point higher than 250°

F., and withstands a peel mode force of 500 grams at 100°

F. for a minimum of about 11 hours and further withstands a shear mode force of 1000 grams at 100°

F. for a minimum of about 11 hours.

6. A hot melt adhesive composition as claimed in claim 5 wherein said polybutylene polymer is a poly(butylene-ethylene) copolymer.