LOW ODOR, LIGHT COLOR, DISPOSABLE ARTICLE CONSTRUCTION ADHESIVE
We have found a novel spray-on adhesive composition made from components including a high melt index copolymer and a high melt tackifier that interact to produce a composition that can form a low odor, light color, non-tacky, hot melt adhesive material that can be used in disposable article manufacture. The adhesive is thermally stable at hot melt application conditions, is low in cost, is easily applied and produces high quality disposable articles.
1 . A hot melt adhesive composition comprising
a) greater than about 40 weight percent of an ethylene comonomer copolymer composition having a melt index of greater than about 800 gm-10 min −1 , the comonomer comprising vinyl acetate, methyl acrylate, ethyl acrylate, n-butyl acrylate, acrylic acid, salts of acrylic acid, methacrylic acid, salts of methacrylic acid, or mixtures thereof;
b) an effective amount of an aromatic modified, cycloaliphatic hydrocarbon resin having a softening point of about 100° C. or greater,
wherein the weight ratio of the copolymer composition to the resin is greater than 1:1.
2 . The hot melt adhesive composition of claim 1 wherein the aromatic modified, cycloaliphatic hydrocarbon resin is an amorphous polymer composition.
3 . The hot melt adhesive composition of claim 1 wherein the adhesive composition comprises greater than about 30 weight percent of aromatic modified, cycloaliphatic hydrocarbon resin.
4 . The hot melt adhesive composition of claim 1 wherein the softening point is about 100° C.
5 . The hot melt adhesive composition of claim 1 wherein the softening point of the tackifier is at about 120° C. or greater.
6 . The hot melt adhesive composition of claim 1 wherein the copolymer composition comprises poly ethylene vinyl acetate.
7 . The hot melt adhesive composition of claim 6 wherein the ratio of the copolymer composition to the resin is about 60:40.
8 . The hot melt adhesive composition of claim 6 wherein the ratio of the copolymer composition to the resin is about 65:35.
9 . The hot melt adhesive composition of claim 1 wherein the adhesive softening point is about 70° C. to 82° C.
10 . A disposable article comprising a film layer bonded to a non-woven layer using a hot melt adhesive composition, the adhesive composition comprising:
a) greater than about 40 weight percent of an ethylene comonomer copolymer composition having a melt index of greater than about 800 gm-10 min −1 , the comonomer comprising vinyl acetate, methyl acrylate, ethyl acrylate, n-butyl acrylate, acrylic acid, salts of acrylic acid, methacrylic acid, salts of methacrylic acid, or mixtures thereof;
b) an effective amount of an aromatic modified, cycloaliphatic hydrocarbon resin having a softening point of about 100° C. or greater, wherein the weight ratio of the copolymer composition to the resin is greater than 1:1.
11 . The disposable article of claim 10 wherein the aromatic modified, cycloaliphatic hydrocarbon resin is an amorphous polymer composition.
12 . The disposable article of claim 10 wherein the adhesive composition comprises greater than about 30 weight percent of aromatic modified, cycloaliphatic hydrocarbon resin.
13 . The disposable article of claim 10 wherein the softening point of the tackifier is about 100° C.
14 . The disposable article of claim 10 wherein the softening point of the tackifier is about 120° C. or greater.
15 . The disposable article of claim 10 wherein the copolymer composition comprises poly ethylene vinyl acetate.
16 . The disposable article of claim 15 wherein the ratio of the copolymer composition to the resin is about 60:40.
17 . The disposable article of claim 15 wherein the ratio of the copolymer composition to the resin is about 65:35.
18 . The disposable article of claim 10 wherein the adhesive softening point is about 70° C. to 82° C.
19 . The disposable article of claim 10 wherein the adhesive composition is provided as a uniform layer, a spiral spray layer, or a fine line layer.
20 . The disposable article of claim 19 wherein the adhesive is applied at about 1 to 8 milligrams per lineal inch.
21 . The disposable article of claim 19 wherein the adhesive is applied at about 1 to 3 milligrams per lineal inch.
22 . The disposable article of claim 10 wherein the nonwoven layer comprises rayon, polyester, polypropylene, polyethylene, nylon, or a copolymer or mixture thereof.
23 . The disposable article of claim 10 wherein the film layer comprises polyethylene, polypropylene, ethylene-propylene copolymers, ethylene acrylate copolymers, ethylene vinyl acetate copolymers, polyvinyl chloride polymers, polyvinylidene chloride polymers, polyester polymers, or copolymers or blends thereof.
24 . The disposable article of claim 10 further comprising sheets, elastics, absorbents, cellulosic fluffs or fill, tissue, or a combination thereof.
25 . The disposable article of claim 10 wherein the disposable article comprises a disposable diaper, an incontinent device, a feminine pad, or a disposable bed pad.