Frosted container

• US 5,230,934 A
• Filed: 12/27/1991
• Issued: 07/27/1993
• Est. Priority Date: 02/27/1991
• Status: Expired due to Term

• Current Assignee: TOYO Seikan Kaisha Limited (Toyo Seikan Group Holdings, Ltd.)
• Original Assignee: TOYO Seikan Kaisha Limited (Toyo Seikan Group Holdings, Ltd.)
• Inventors: Iwamoto, Toshiyuki, Yamaguchi, Yuji, Sakano, Kozaburo
• Primary Examiner(s): Kight, III, John
• Assistant Examiner(s): Truong, Duc
• Application Number:
  US07/813,922
• Time in Patent Office: 578 Days
• Field of Search: 428/35.7, 428/475.8, 428/483, 525/60, 525/55, 525/56, 525/61
• US Class Current: 428/35.7
• CPC Class Codes: B29C 49/0005 characterised by the material
• CPC Class Codes: B29K 2995/0024 Matt surface
• CPC Class Codes: C08L 23/06 Polyethene
• CPC Class Codes: C08L 23/0815 Copolymers of ethene with aliphatic 1-olefins
• CPC Class Codes: C08L 23/10 Homopolymers or copolymers of propene
• CPC Class Codes: C08L 23/16 Elastomeric ethene-propene or ethene-propene-diene copolymers, e.g. EPR and EPDM rubbers
• CPC Class Codes: C08L 2666/06 Homopolymers or copolymers of unsaturated hydrocarbons; Derivatives thereof
• CPC Class Codes: C08L 2666/24 Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: Y10T 428/1352 Polymer or resin containing [i.e., natural or synthetic]
• CPC Class Codes: Y10T 428/31743 Next to addition polymer from unsaturated monomer[s]
• CPC Class Codes: Y10T 428/31797 Next to addition polymer from unsaturated monomers

Abstract

At least an outer layer of a plastic container is formed of a blend including an ethylene-propylene block copolymer containing 3 to 10% by weight, particularly 5 to 9% by weight of ethylene and a melt flow rate of 0.8 to 10 g/10 min. and a polyethylene having a given density at a weight ratio of 9:1 to 5:5. A plastic container made of an olefin resin having a frosted or matted appearance can be manufactured with excellent moldability without requiring any special working such as sand blasting the cavity surface of a mold. The container will gives an impression of shade off, depth and high grade.

Claims

1. A plastic container having a frosted appearance comprising at least an outer layer which is formed of a blend comprising (A) and ethylene-propylene block copolymer containing 3 to 10% by weight of ethylene and having a melt flow rate of 0.8 to 10 g/10 min. and (B) polyethylene having a density of 0.925 to 0.970 g/cm³, at a weight ratio (a):

(B) of 9;

1 to 5;

5.

3. A plastic container as defined in claim 1 or 2 in which said polyethylene is a high density polyethylene having a density of 0.940 to 0.970 g/cm³.

4. A plastic container as defined in claim 1 or 2 in which said polyethylene is linear low density polyethylene having a density of 0.925 to 9.45 g/cm³.

5. A plastic container as defined in claim 4 in which said blend contains the ethylene-propylene block copolymer and the linear low density polyethylene at a weight ratio of 9:

1 to 5;

5.

6. A plastic container as defined in claim 1 wherein it is formed of a laminate composed of a polyethylene layer forming said outside surface and a layer containing an ethylene/vinyl alcohol copolymer.

8. A plastic container as defined in claim 1 or 2 wherein said blend comprises a continuous matrix of said ethylene-propylene block copolymer and a dispersion phase of said polyethylene.

9. A plastic container as defined in claim 1 or 2 wherein said blend comprises (A) said ethylene-propylene block copolymer and (B) said polyethylene at a blend weight ratio (A):

(B) of 8;

2 to 7;

3.

2. A plastic container having a frosted appearance, comprising a laminate comprising (i) an outer layer which is formed of a blend of (A) an ethylene-propylene block copolymer containing 3 to 10% by weight of ethylene and having a melt flow rate of 0.8 to 10 g/10 min. and (B) a polyethylene having a density of 0.925 to 0.970 b/cm³ at a blend weight ratio (A):

(B) of 9;

1 to 5;

5 and (ii) an inner layer which is formed of an ethylene-propylene random copolymer containing 1 to 85 by weight of ethylene and a melt flow rate of 1 to 5 g/10 min.

7. A plastic container as defined in claim 2 in which an intermediate layer formed of an ethylene/vinyl alcohol copolymer is formed between said outer layer and said inner layer.

10. A plastic bottle having a frosted appearance comprising an outer layer of a blend comprising (A) an ethylene-propylene block copolymer containing 3 to 10% by weight of ethylene and having a melt flow rate of 0.8 to 10 g/10 min. and (B) a polyethylene having a density of 0.925 to 0.975 g/cm³ at a weight ratio (A):

(B) of 9;

1 to 5;

5, and an inner layer of an ethylene-propylene random copolymer containing 1 to 8% by weight by ethylene and a melt flow rate of 1 t 5 g/10 min., said outer layer occupying at least 3% of the thickness of the wall of the bottle.