Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Processes of preparing a desired or intentional composition...
Reexamination Certificate
1999-07-29
2001-05-22
Wu, David W. (Department: 1713)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Processes of preparing a desired or intentional composition...
C524S270000, C524S515000, C524S578000, C524S528000, C524S570000, C526S935000
Reexamination Certificate
active
06235818
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a hot-melt adhesive composition. More particularly, the present invention is concerned with a hot-melt adhesive composition which exhibits excellent adhesive strength and can be used as an adhesive for styrene resins.
BACKGROUND OF THE INVENTION
It is well known that hot-melt adhesives comprising a base of a polymer such as a polyolefin, a polyamide, a polyester, a vinyl acetate copolymer, a cellulose derivative, polymethyl methacrylate, a polyvinyl ether or a polyurethane and, added to the base, a tackifier, exhibit adhesive effect when applied to, for example, a label, a kraft tape or a cloth tape and heated.
In recent years, the fields of application of hot-melt adhesives are rapidly increasing because the hot-melt adhesives are superior to the conventional solvent containing adhesives in the coating speed, safety, working environment and energy saving. Commonly employed hot-melt adhesives comprise a base polymer of EVA or a styrene/conjugated diene block copolymer added to the base polymer, a tackifier and a low-molecular-weight polyolefin. Enhanced performance of adhesives is increasingly demanded in recent years and it is required that adhesives exhibit high adhesive strength to a variety of materials.
For example, specifically, the styrene content of the adhesive based on the styrene/conjugated diene block copolymer is increased for improving the heat resistance of the adhesive. However, the adhesive strength of the resultant adhesive is not satisfactory, and it has been difficult to realize a desirable balance of heat resistance and adhesive property for the adhesive.
OBJECT OF THE INVENTION
The present invention has been made in view of the above state of the prior art. It is an object of the present invention to provide a hot-melt adhesive composition having excellent adhesive strength.
SUMMARY OF THE INVENTION
The first hot-melt adhesive composition of the present invention comprises:
100 parts by weight of a tackifier (B), and
1 to 900 parts by weight of an &agr;-olefin/aromatic vinyl compound random copolymer (C).
The second hot-melt adhesive composition of the present invention comprises:
100 parts by weight of a base polymer (A),
1 to 900 parts by weight of a tackifier (B), and
1 to 1000 parts by weight of an &agr;-olefin/aromatic vinyl compound random copolymer (C).
The third hot-melt adhesive composition of the present invention comprises:
100 parts by weight of a base polymer (A),
10 to 300 parts by weight of a tackifier (B), and 10 to 400 parts by weight of an &agr;-olefin/aromatic vinyl compound random copolymer (C).
In the present invention, the base polymer (A) is, for example, at least one polymer selected from the group consisting of a polyolefin (a-1), a polar group containing polymer (a-2) and an aromatic vinyl compound/conjugated diene copolymer (a-3). Of these, the aromatic vinyl compound/conjugated diene copolymer (a-3) is preferred.
It is preferred in the present invention that the &agr;-olefin/aromatic vinyl compound random copolymer (C) be an ethylene/aromatic vinyl compound random copolymer and that the &agr;-olefin/aromatic vinyl compound random copolymer (C) contain structural units derived from an aromatic vinyl compound in an amount of 1 to 80 mol %.
Further, the second and third hot-melt adhesive compositions of the present invention may comprise a low-molecular-weight polyolefin (D) in an amount of 1 to 100 parts by weight per 100 parts by weight of the base polymer (A) in addition to the base polymer (A), the tackifier (B) and the &agr;-olefin/aromatic vinyl compound random copolymer (C).
The first hot-melt adhesive composition of the present invention may comprise a low-molecular-weight polyolefin having an intrinsic viscosity (&eegr;) of 0.01 to 0.6 dl/g (D) in an amount of 1 to 100 parts by weight per 100 parts by weight of the tackifier (B) in addition to the tackifier (B) and the &agr;-olefin/aromatic vinyl compound random copolymer (C).
DETAILED DESCRIPTION OF THE INVENTION
The hot-melt adhesive composition of the present invention will be described in detail below.
The first hot-melt adhesive composition of the present invention comprises a tackifier (B) and an &agr;-olefin/aromatic vinyl compound random copolymer (C) optionally together with a low-molecular-weight polyolefin (D).
Each of the second and third hot-melt adhesive compositions of the present invention comprises a base polymer (A), a tackifier (B) and an &agr;-olefin/aromatic vinyl compound random copolymer (C) optionally together with a low-molecular-weight polyolefin (D).
First, each of the above components (A), (B), (C) and (D) for use in the present invention will be described.
Base Polymer (A)
The base polymer (A) added according to necessity in the present invention is not particularly limited as long as it is a polymer generally employed in common hot-melt adhesives. Examples of suitable base polymers (A) include a polyolefin (a-1), a polar group containing polymer (a-2) and an aromatic vinyl compound/conjugated diene copolymer (a-3)
Polyolefin (a-1)
Examples thereof include:
polyethylenes (HDPE, LDPE, LLDPE, etc.);
polypropylenes (atactic polypropylene, syndiotactic polypropylene, etc.); and
ethylene/propylene copolymers.
Polar Group Containing Polymer (a-2)
Examples thereof include:
(1) ethylene/vinyl acetate copolymer (EVA);
(2) modified EVA polymers such as saponified EVA and graft-modified EVA;
(3) ethylene/(meth)acrylate copolymers such as ethylene/ethyl(meth)acrylate (EEA);
(4) ionomer resins obtained by partially neutralizing ethylene/(meth)acrylic acid copolymer, such as polymer conmercially available by the trade name of Himilan from Mitsui Du Pont Polychemical;
(5) ethylene/propylene/(meth)acrylic acid terpolymers;
(6) polyamides: products obtained by reacting a dibasic acid with a diamine, for example, those obtained by reacting a dimer acid which is a dimer of a fatty acid such as soybean oil, tung oil or tall oil with an alkyldiamine such as ethylenediamine or diethylenetriamine and nylons such as nylon-12, examples thereof including polymers commercially available by the trade name of Diamid (Daicel Chemical Industries, Ltd.), Platilon (Toagosei Chemical Industry Co., Ltd.) and Amilan (Toray Industries, Inc.);
(7) polyesters, for example, those commercially available by the trade name of Ester Resin 200 or 300 (Toyobo Co., Ltd.) and Vitel 200 or 300 (Goodyear Tire & Rubber Co., Ltd.); and
(8) vinyl acetate copolymers such as vinyl acetate/crotonic acid copolymer, vinyl acetate/phthalic anhydride copolymer and vinyl acetate/vinylpyrrolidone copolymer, cellulose derivative polymers, polymethyl methacrylate polymers, polyvinyl ether polymers, polyurethane polymers and thermosetting resin polymers.
Aromatic Vinyl Compound/conjugated Diene Copolymer (a-3)
The aromatic vinyl compound/conjugated diene copolymer (a-3) is a copolymer of an aromatic vinyl compound and a conjugated diene compound or a product of hydrogenation thereof. Examples thereof include styrene/butadiene random copolymer, styrene/isoprene random copolymer, butadiene/polystyrene block copolymer, polystyrene/polyisoprene block copolymer, polystyrene/polyisoprene/polystyrene triblock copolymer, polystyrene/polybutadiene/polystyrene triblock copolymer, poly((&agr;-methylstyrene)/polybutadiene/poly(&agr;-methylstyrene) triblock copolymer and products of hydrogenation thereof. These polymers, both unhydrogenated and hydrogenated polymers, are commercially available. For example, such polymers are commercially available by the trade name of Cariflex TR-1101, TR-1107 and TR-4113 (Shell Int. Chem. Co., Ltd.), Kraton G-6500, G-6521, G-1650, G-1652 and G-1657 (Shell Chem. Co., Ltd.) and Solprene and hydrogenated Solprene (Phillips Petroleum Co., Ltd.).
In the present invention, the above base polymers can be used either individually or in combination. Of the above base polymers, the aromatic vinyl compound/conjugated diene copolymer and products of hydrogenation thereof are preferred. The aromatic vinyl compound/conjugated diene copolymer i
Morizono Kenichi
Okada Keiji
Tokita Suguru
Egwim Kelichi C.
Mitsui Chemicals
Wu David W.
LandOfFree
Hot melt adhesive composition containing... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hot melt adhesive composition containing..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hot melt adhesive composition containing... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2524969