Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – At least one aryl ring which is part of a fused or bridged...
Reexamination Certificate
2001-10-10
2003-12-09
Wu, David W. (Department: 1713)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
At least one aryl ring which is part of a fused or bridged...
C524S451000, C525S088000, C525S095000, C525S420000, C293S120000
Reexamination Certificate
active
06660797
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a propylene-based resin composition and to a molding method using the same, more particularly to a propylene-based resin composition high in rigidity and resistance to impact, excellent in resistance to scratching, and also excellent in moldability (injection moldability or press injection moldability), and to a molding method using the same.
BACKGROUND OF THE INVENTION
Recently, propylene-based composite materials comprising a propylene-based resin material incorporated with an inorganic filler (e.g., talc) and/or elastomer have been widely used for automobile parts, e.g., bumpers, instrument panels, door trims and pillar trims, because of their well-balanced properties and excellent moldability.
The propylene-based resin material is frequently incorporated with an elastomer, when it is to be used for automobile parts required to have high impact-related characteristics. However, increasing the elastomer content tends to cause loss of bending modulus of elasticity and bending strength. A filler, e.g., talc, has been incorporated in an attempt to improve these properties, but has failed to significantly improve bending strength, although successfully improving bending modulus of elasticity. Therefore, the conventional propylene-based composite material, although exhibiting a high bending modulus of elasticity, is not well-balanced with respect to impact resistance and bending strength.
Many automobile interiors are those which a person directly comes into contact with, and their feel of material, i.e., feel of rigidity, firmness or the like, depends on their bending strength. Therefore, a propylene-based composite material is required to be well-balanced with respect to impact resistance and bending strength.
For improvement of resistance of propylene-based resin composition to scratching, various techniques have been proposed; e.g., incorporation of a specific polyethylene (Japanese Patent Laid-Open No.73034/1982), use of a filler of specific particle size (Japanese Patent Laid-Open No.8235/1982), and addition of a nucleating agent or the like to improve crystallinity and hence surface hardness.
These techniques achieve the above objects to some extent. However, the propylene-based resin composition is required to have still higher resistance to scratching, as embossed patterns on the molded articles are becoming more diversified.
It is an object of the present invention to provide a propylene-based resin composition which gives the molded articles excellent in resistance to scratching, and, at the same time, in moldability (injection moldability or press injection moldability) and balanced properties (high rigidity and impact strength), to solve the above problems. It is another object of the present invention to provide a method for molding the above propylene-based resin composition, to produce high-performance industrial parts and automobile parts, in particular automobile interiors, at low cost.
DISCLOSURE OF THE INVENTION
The inventors of the present invention have found, after having extensively studied to solve the above problems, that the resin composition solving the above problems can be obtained by incorporating a specific propylene-based resin composition of high impact resistance with a specific high-crystallinity propylene resin material and inorganic filler or, depending on circumstances, pigment-containing resin material; or, depending on circumstances, by incorporating the above specific propylene-based resin composition of high impact resistance and/or high-crystallinity propylene resin material and specific inorganic filler with a specific ethylene/&agr;-olefin copolymer rubber and/or specific polyethylene and/or fatty acid amide or its derivative, and by mixing or melting/kneading these components, reaching the present invention.
The first invention provides a propylene-based resin composition produced by mixing and/or melting/kneading the following components (A) and (B):
(A) Propylene-based resin composed of the following components (a1), (a2) and (a3); 90 to 40 wt. %
(a1) Propylene/ethylene block copolymer, composed of 60 to 83 wt. % of crystalline propylene homopolymer component (a1-1 unit) and 17 to 40 wt. % of ethylene/propylene random copolymer component (a1-2 unit) containing 30 to 52 wt. % of ethylene and having a weight-average molecular weight of 230,000 to 600,000; and having a melt flow rate (230° C., load: 2.16 kg) of 15 to 150 g/10 min. and number of gels of 100 or less for those having a size of 50 &mgr;m or more in the molded article of 25 cm
2
(area) and 0.5 mm (thickness); 100 wt. parts.
(a2) Talc having an average particle size of 0.5 to 15 &mgr;m; 0 to 200 wt. parts.
(a3) Ethylene/&agr;-olefin copolymer rubber, containing 20 to 50 wt. % of &agr;-olefin of 3 to 8 carbon atoms and having a melt flow rate (230° C., load: 2.16 kg) of 0.3 to 100 g/10 min; 0 to 20 wt. parts.
(B) Propylene-based resin material composed of the following components (b1) and (b2); 10 to 60 wt. %:
(b1) Propylene homopolymer or propylene/ethylene block copolymer, having a component insoluble in orthodichlorobenzene at below 120° C. accounting for 8 wt. % or more of the component insoluble at below 100° C., when fractionated with orthodichlorobenzene as the solvent, wherein the component insoluble at below 100° C. has a weight-average molecular weight of 200,000 or more and melt flow rate (230° C., load: 2.16 kg) of 0.3 to 70 g/10 min; 15 to 80 wt. parts.
(b2) Talc or wollastonite having an average particle size of 0.5 to 15 &mgr;m; 20 to 85 wt. parts.
The second invention provides a propylene-based resin composition produced by mixing and/or melting/kneading the following components (A) and (B):
(A) Propylene-based resin material composed of the following components (a1), (a2) and (a3): 90 to 40 wt. %
(a1) Propylene/ethylene block copolymer, composed of 60 to 83 wt. % of crystalline propylene homopolymer component (a1-1 unit) and 17 to 40 wt. % of ethylene/propylene random copolymer component (a1-2 unit) containing 30 to 52 wt. % of ethylene and having a weight-average molecular weight of 230,000 to 600,000; and having a melt flow rate (230° C., load: 2.16 kg) of 20 to 150 g/10 min. and number of gels of 100 or less for those having a size of 50 &mgr;m or more in the molded article of 25 cm
2
(area) and 0.5 mm (thickness); 100 wt. parts.
(a2) Talc having an average particle size of 0.5 to 15 &mgr;m; 0 to 200 wt. parts.
(a3) Ethylene/&agr;-olefin copolymer rubber containing 20 to 50 wt. % of &agr;-olefin of 3 to 8 carbon atoms and having a melt flow rate (230° C., load: 2.16 kg) of 0.3 to 15 g/10 min; 0 to 10 wt. parts.
(B) Propylene-based resin material composed of the following components (b1) and (b2); 10 to 60 wt. %:
(b1) Homopolypropylene or propylene/ethylene block copolymer, having a component insoluble in orthodichlorobenzene at below 120° C. accounting for 10 wt. % or more of the component insoluble at below 100° C., when fractionated with orthodichlorobenzene as the solvent, wherein the component insoluble at below 100° C. has a weight-average molecular weight of 200,000 or more and melt flow rate (230° C., load: 2.16 kg) of 0.3 to 20 g/10 min; 100 wt. parts.
(b2) Talc having an average particle size of 0.5 to 15 &mgr;m; 0 to 200 wt. parts.
The third invention provides a propylene-based resin composition, composed of 100 wt. parts of the totaled components (A) and (B) for the first invention incorporated with 10 wt. parts or less of the following component (C), and produced by mixing and/or melting/kneading these components:
(C) Propylene-based colorant material, composed of the following components (c1), (c3), (c4), (c5) and (c6):
(c1) Propylene homopolymer, propylene/ethylene block copolymer, propylene/ethylene random copolymer, polyethylene or ethylene-based rubber, having a melt flow rate (230° C., load: 2.16 kg) of 0.3 to 200 g/10 min.; 20 to 99.9 wt. %.
(c3) Ethylene/&agr;-olefin copolymer rubber containing 20 to 50 wt. % of &agr;-olefin of 3 to 8 carbon atoms and having a melt flow rate (230° C.,
Banno Yoshihiro
Isoi Masaaki
Kobayashi Akira
Sobajima Yoshihiro
Armstrong Westerman & Hattori, LLP
Hu Henry S
Japan Polychem Corporation
Wu David W.
LandOfFree
Propylene resin composition and method for molding the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Propylene resin composition and method for molding the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Propylene resin composition and method for molding the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3098981