Polypropylene type aqueous dispersion, polypropylene type composite aqueous emulsion composition and its use

1. A process for producing a polypropylene type aqueous dispersion, said process comprises dispersing following component (a) in component (c) with component (b);

(a) a polypropylene type polymer and/or a modified polypropylene type polymer, prepared by a single site catalyst 100 parts by weight,

(b) a surfactant 1 to 100 parts by weight, and

(c) water 100 to 1,000 parts by weight,

wherein the component (a) has a main chain having the following features (1) and (2) and dispersion particles in the dispersion have an average particle size of at most 0.5 μm,

Feature (1) when observing a peak derived from a carbon atom of a methyl group in a propylene unit chain part comprising a head-to-tail bond by 13 C-NMR and fixing a chemical shift of a peak top at a peak attributable to pentad expressed by mmmm to 21.8 ppm, a ratio (S 1 /S) of an area S 1 of a peak of a peak top at 21.8 ppm to a total area S of peaks at from 19.8 ppm to 22.1 ppm is at least 10% and at most 60%, and when an area of a peak (mmmr) of a peak top at 21.5 to 21.6 ppm is expressed as S 2 , 4+2S 1 /S 2 >5, and

Feature (2) a content ratio (mol ratio) of propylene unit (A): other olefin unit (B) is from 100:0 to 90:10.

2. The process according to claim 1 , wherein the surfactant of component (b) is at least one of anionic, cationic and amphoteric surfactants.

3. The process according to claim 1 , wherein the surfactant of component (b) is a nonionic surfactant.

4. The process according to claim 1 , wherein the surfactant of component (b) comprises at least two kinds of surfactants.

5. The process according to claim 1 , which further contains a basic material as a component (d) in an amount of from 0.01 to 10 parts by weight to 100 parts by weight of the component (a).

6. The process according to claim 1 , wherein the other olefin unit (B) is an ethylene unit and/or a butene unit.

7. The process according to claim 1 , wherein the polypropylene type polymer and/or the modified polypropylene type polymer of component (a) have a weight average molecular weight (Mw) of from 10,000 to 300,000 measured by GPC.

8. The process according to claim 1 , wherein the modified polypropylene type polymer of component (a) is a modified polypropylene type polymer modified by grafting with an unsaturated carboxylic acid and/or its derivative selected from the group consisting of a C 3 -C 25 unsaturated carboxylic acid, its acid anhydride and its ester.

9. The process according to claim 4 , wherein the surfactant of component (b) comprises a nonionic surfactant (b1) having a hydrophile-lipophile balance (HLB) value in a range of from 13.5 to 14.5 and a nonionic surfactant (b2) having an HLB value in a range of from 16.0 to 17.0, and their blending ratio (b1/b2) is from 1/9 to 9/1.

10. The process according to claim 1 , which further contains a polymer as a component (e) other than a polypropylene type polymer and a modified polypropylene type polymer in addition to the above components (a), (b) and (c) in an amount of from 1 to 5,000 parts by weight to 100 parts by weight of the component (a).

11. The process according to claim 10 , wherein the polymer of component (e) other than a polypropylene type polymer and a modified polypropylene type polymer is at least one member selected from the group consisting of a (meth)acrylic polymer, a urethane type polymer and an epoxy type polymer.

12. An aqueous dispersion obtained by the process according to claim 1 .

13. A coating agent, a paint, an ink or an adhesive comprising a polypropylene type aqueous dispersion as defined in claim 12 .

14. A polypropylene type resin-coated product obtained by coating a substrate comprising a crystalline polypropylene molded product with a paint as defined in claim 13 .

15. The polypropylene type resin-coated molded product according to claim 14 , wherein the crystalline polypropylene constituting the substrate is a propylene homopolymer or a propylene.ethylene block copolymer comprising a propylene homopolymer part and a propylene.ethylene copolymer part.

16. The polypropylene type resin-coated molded product according to claim 14 , wherein the substrate is a molded product comprising a polypropylene type resin composition containing an elastomer component in an amount of from 1 to 90 parts by weight to 100 parts by weight of the crystalline polypropylene.

17. The polypropylene type resin-coated molded product according to claim 14 , wherein the substrate is a molded product comprising a polypropylene type resin composition containing an inorganic filler in an amount of from 1 to 80 parts by weight to 100 parts by weight of the crystalline polypropylene.

18. The polypropylene type resin-coated molded product according to claim 14 , wherein the substrate is a molded product having a surface glossiness (JIS-K7105, incident angle 60°) of at least 30%, which comprises an electroconductive polypropylene type resin composition containing an electroconductive carbon.

19. The polypropylene type resin-coated molded product according to claim 18 , wherein the electroconductive carbon has a particle size of from 10 to 100 nm, a DBP oil absorption number of from 50 to 900 ml/g and a specific surface area of from 100 to 1,500 m 2 /100 g.

20. The polypropylene type resin-coated molded product according to claim 18 , wherein the electroconductive carbon is contained in an amount of from 0.1 to 25 parts by weight to 100 parts by weight of the crystalline polypropylene.