Self-emulsification type emulsion containing modified polypropylene resin
The present invention provides a self-emulsification type emulsion exhibiting excellent adhesion to olefin-based base materials such as polyethylene and polypropylene without using an emulsifier. The self-emulsification type emulsion of the present invention comprises a tackifier and a modified polypropylene resin having an anionic functional group, and satisfies (1) and (2) given below: (1) the modified polypropylene resin having an anionic functional group is dispersed in water in the absence of an emulsifier, and (2) a dispersion particle comprising the modified polypropylene resin having an anionic functional group surrounds the tackifier.
1. A self-emulsification type emulsion comprising a tackifier and a modified polypropylene resin having an anionic functional group, wherein
(1) the modified polypropylene resin having an anionic functional group is dispersed in water in the absence of an emulsifier,
(2) the tackifier alone cannot be stably dispersed or dissolved in water as it phase-separates and precipitates in water,
(3) a dispersion particle comprising the modified polypropylene resin having an anionic functional group includes the tackifier inside the dispersion particle,
(4) the modified polypropylene resin dispersion particle has a Z mean particle diameter of 500 nm or less.
2. The self-emulsification type emulsion according to claim 1 , wherein the tackifier is contained in the range of 5 parts by weight or more to 80 parts by weight or less per 100 parts by weight of the modified polypropylene resin.
3. An adhesive composition comprising the self-emulsification type emulsion according to claim 1 .
4. An adhesive composition comprising the self-emulsification type emulsion according to claim 2 .
5. The adhesive composition according to claim 3 , which is an adhesive for a polyolefin-based resin.
6. The adhesive composition according to claim 4 , which is an adhesive for a polyolefin-based resin.
7. A method for producing a self-emulsification type emulsion according to claim 1 , said method comprising
dissolving a tackifier and a modified polypropylene resin having an anionic functional group in a solvent and water by heating, adding a basic substance thereto, and then removing the solvent,
wherein the method is performed in the absence of an emulsifier, and
wherein the tackifier alone cannot be stably dispersed or dissolved in water as it phase-separates and precipitates in water.