Provided are a hot-melt adhesive having high flowability in a molten state and exhibiting high adhesion strength in bonding PP nonwoven fabrics and further exhibiting high adhesion strength in bonding PE film-PP nonwoven fabric, and a base polymer for a hot-melt adhesive. The hot-melt adhesive contains (A) a propylene-based polymer satisfying the following (Ai) to (Aiv), and (B) an olefin-based copolymer satisfying the following (Bi) and (Bii); and the base polymer for a hot-melt adhesive consists of a mixture of (A) a propylene-based polymer satisfying the following (Ai) to (Aiv) and (B) an olefin-based copolymer satisfying the following (Bi) and (Bii) and satisfies the following (1) and (2). (Ai) the melting point is 120 C. or lower, (Aii) the Mw is 10,000 to 150,000, (Aiii) the Mw/Mn is 2.5 or less, (Aiv) the penetration is 8 or less, (Bi) the penetration is 15 or more, (Bii) the melting point is 90 C. or higher, (1) the tensile elastic modulus at 23 C. is 400 MPa or less, and (2) the semi-crystallization time at 23 C. is 20 minutes or less.

The present invention is related to pressure-sensitive hot melt adhesive compositions and their applications. In particular, the adhesive compositions described herein comprise a block copolymer component, a hydrocarbon tackifier resin component, and a propylene-based polymer component.

The present invention is related to pressure-sensitive hot melt adhesive compositions and their applications. In particular, the adhesive compositions described herein comprise a block copolymer component, a hydrocarbon tackifier resin component, and a propylene-based polymer component.

The present invention is related to pressure-sensitive hot melt adhesive compositions and their applications. In particular, the adhesive compositions described herein comprise a block copolymer component, a hydrocarbon tackifier resin component, and a propylene-based polymer component.

Hot melt adhesives may comprise linear alpha olefins (LAOs) or LAO-derived compounds as an at least partial replacement for paraffinic white oil diluents. Such adhesive compositions may comprise an ethylenically unsaturated polymer or copolymer, a tackifier, and a diluent. The diluent may comprise at least one of: one or more C.sub.18+ linear alpha olefins (LAOs) having a kinematic viscosity of about 4 cSt or less at 135 C.; one or more LAO dimers formed from one or more C.sub.18+ LAOs, the one or more LAO dimers having an internal olefin and a kinematic viscosity of about 6 cSt or less at 135 C., or one or more paraffinic hydrocarbons having an even carbon number distribution and formed through dimerization of one or more C.sub.18+ LAOs and subsequent reduction. The one or more paraffinic hydrocarbons may have a kinematic viscosity (ASTM D-445) of about 4 cSt to about 8 cSt at 135 C.

Hot melt adhesives may comprise linear alpha olefins (LAOs) or LAO-derived compounds as an at least partial replacement for paraffinic white oil diluents. Such adhesive compositions may comprise an ethylenically unsaturated polymer or copolymer, a tackifier, and a diluent. The diluent may comprise at least one of: one or more C.sub.18+ linear alpha olefins (LAOs) having a kinematic viscosity of about 4 cSt or less at 135 C.; one or more LAO dimers formed from one or more C.sub.18+ LAOs, the one or more LAO dimers having an internal olefin and a kinematic viscosity of about 6 cSt or less at 135 C., or one or more paraffinic hydrocarbons having an even carbon number distribution and formed through dimerization of one or more C.sub.18+ LAOs and subsequent reduction. The one or more paraffinic hydrocarbons may have a kinematic viscosity (ASTM D-445) of about 4 cSt to about 8 cSt at 135 C.

An adhesive resin composition including a propylene polymer (A), an ethylene polymer (B), and a thermoplastic resin (C) including a copolymer containing not less than 60 mol % and not more than 99 mol % of structural units derived from 4-methyl-1-pentene, and not less than 1 mol % and not more than 40 mol % of structural units derived from a C2-C20 -olefin other than 4-methyl-1-pentene, these structural units representing total 100 mol % of the copolymer, the thermoplastic resin (C) showing a melting point Tm of not more than 199 C. or showing substantially no melting point as analyzed with a differential scanning calorimeter (DSC). The total of the components (A), (B) and (C) includes 45 to 75 parts by mass of the component (A), 5 to 20 parts by mass of the component (B), and 15 to 45 parts by mass of the component (C).

An adhesive resin composition including a propylene polymer (A), an ethylene polymer (B), and a thermoplastic resin (C) including a copolymer containing not less than 60 mol % and not more than 99 mol % of structural units derived from 4-methyl-1-pentene, and not less than 1 mol % and not more than 40 mol % of structural units derived from a C2-C20 -olefin other than 4-methyl-1-pentene, these structural units representing total 100 mol % of the copolymer, the thermoplastic resin (C) showing a melting point Tm of not more than 199 C. or showing substantially no melting point as analyzed with a differential scanning calorimeter (DSC). The total of the components (A), (B) and (C) includes 45 to 75 parts by mass of the component (A), 5 to 20 parts by mass of the component (B), and 15 to 45 parts by mass of the component (C).

A hot melt adhesive material and articles made using the hot melt adhesive to assemble structures in an article. The adhesive material typically is manufactured by blending amorphous polymer with a heterophase polymer having crystallinity into an adhesive composition.

Adhesives, methods to bond substrates together with the adhesives, and articles of manufacture comprising the adhesives are described. It has been discovered that an adhesive with a polymer content greater than 70 weight percent can be formulated with a blend of (i) a metallocene catalyzed polypropylene polymer that has a density range of about 0.70 to about 0.91 g/cm.sup.3 and a melt viscosity less than 50,000 cP at 190 C. and (ii) a Ziegler-Natta catalyzed amorphous polybutene and/or polypropylene copolymer. Such adhesives have high creep resistance making them particularly well suited for disposable personal care garments.