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US5830402A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing multilayer molded articles

Assignee: Sumitomo Chemical Co Ltd
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Filing: 1996-06-17
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Granted: 1998-11-03
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Expires: 2016-06-17
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Abstract

Abstract A multilayer molded article comprising a skin and a substrate consisting of a polypropylene resin composition having a crystallization rate of 45 second or less, said skin being integrally adhered to the substrate. Said multilayer molded article can be produced by feeding a skin material and a molten polypropylene resin composition having a crystallization rate of 45 second or less between a pair of upper and lower molds, molding the molten polypropylene resin composition in the molds with simultaneous adhering of the skin material to the surface of the molded resin composition and then cooling the molten resin composition to solidify the same. Said multilayer molded article has a small deformation degree without the soft feeling of the skin material being impaired.

Inventors

  • 👤 Hiroyuki Harada
  • 👤 Kenichi Higashi
  • 👤 Masahito Matsumoto
  • 👤 Nobuhiro Usui

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 21:10
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B29; B29C; B29C43/00; B29C43/02; B29C43/18; B29C43/183; B29C43/184; B29C43/003; B29C45/00; B29C45/14; B29C45/1418; B29C70/00; B29C70/68; B29C70/78; B32B37/00; B32B37/04; B29K; B29K2023/00; B29K2023/10; B29K2023/12; B29K2995/00; B29K2995/0037; B29K2995/0041

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 107 words
A process for producing a multilayer molded article wherein said article comprises a skin and a substrate consisting of a thermoplastic resin, which process comprises (a) feeding a skin material and a molten thermoplastic resin between a pair of upper and lower molds, (b) molding the molten resin in the molds whereby there is simultaneous adhering of the skin material to the surface of the molded resin, and then (c) cooling the molten resin to solidify the same, wherein said thermoplastic resin is a polypropylene resin composition having a crystallization rate of 45 seconds or less and whereby deformation of the multilayer molded article is substantially prevented.
Claim 2
Dependent Claim 107 words
A process for producing a multilayer molded article wherein said article comprises a skin and a substrate consisting of a thermoplastic resin, which process comprises (a) feeding a skin material and a molten thermoplastic resin between a pair of upper and lower molds, (b) molding the molten resin in the molds whereby there is simultaneous adhering of the skin material to the surface of the molded resin, and then (c) cooling the molten resin to solidify the same, wherein said thermoplastic resin is a polypropylene resin composition having a crystallization rate of 45 seconds or less and whereby deformation of the multilayer molded article is substantially prevented.
Claim 3
Dependent Claim 162 words
A process for producing a multilayer molded article wherein said article comprises a skin and a substrate consisting of a thermoplastic resin, which process comprises (a) feeding a skin material between an unclosed pair of upper and lower molds, (b) allowing the upper mold to close to a predetermined position, (c) feeding a molten thermoplastic resin between the skin material and the lower mold, (d) allowing the upper mold to close further while feeding the molten thermoplastic resin or after completion of feeding the predetermined amount of the molten thermoplastic resin, (e) clamping the upper and lower molds together and molding the molten thermoplastic resin in the molds to thereby simultaneously adhere the skin material to the surface of the molded resin, and then (f) cooling the molten resin to solidify the same, wherein said thermoplastic resin is a polypropylene resin composition having a crystallization rate of 45 seconds or less and whereby deformation of the multilayer molded article is substantially prevented.
Claim 4
Dependent Claim 162 words
A process for producing a multilayer molded article wherein said article comprises a skin and a substrate consisting of a thermoplastic resin, which process comprises (a) feeding a skin material between an unclosed pair of upper and lower molds, (b) allowing the upper mold to close to a predetermined position, (c) feeding a molten thermoplastic resin between the skin material and the lower mold, (d) allowing the upper mold to close further while feeding the molten thermoplastic resin or after completion of feeding the predetermined amount of the molten thermoplastic resin, (e) clamping the upper and lower molds together and molding the molten thermoplastic resin in the molds to thereby simultaneously adhere the skin material to the surface of the molded resin, and then (f) cooling the molten resin to solidify the same, wherein said thermoplastic resin is a polypropylene resin composition having a crystallization rate of 45 seconds or less and whereby deformation of the multilayer molded article is substantially prevented.
Claim 5
Dependent Claim 21 words
A process according to claim 1 or 2, wherein the polypropylene resin composition has a melt index of 20 or more.
Claim 6
Dependent Claim 22 words
A process according to claim 1 or 2, wherein the polypropylene resin composition has a crystallization rate of 35 seconds or less.
Claim 7
Dependent Claim 57 words
A process according to claim 1 or 2, wherein the crystallization rate is a value obtained by melting the polypropylene resin composition, subjecting the polypropylene resin composition to isothermal crystallization of 130° C. and measuring the time required for crystallizing 1/2 of the total amount of resin to be crystallized by means of a differential scanning calorimeter.
Claim 8
Dependent Claim 35 words
A process according to claim 1, wherein said polypropylene resin contains a nucleating agent for controlling the crystallization rate, and said nucleating agent is a metal salt of an organic acid or a sorbitol compound.
Claim 9
Dependent Claim 20 words
A process according to claim 6, wherein said nucleating agent is aluminum p-t-butylbenzoate, sodium bis(4-t-phenyl) phosphate, dibenzylidenesorbitol or 1,3,2,4-di-t-ethyl benzylidenesorbitol.
Claim 10
Dependent Claim 36 words
A process according to claim 7, wherein said nucleating agent is present in an amount of 0.05-0.3% by weight based on the weight of the polypropelene resin composition and wherein said nucleating agent is aluminum p-t-butybenzoate.
Claim 11
Dependent Claim 35 words
A process according to claim 1 or 2, wherein the polypropelene resin composition has a melt index of at least 20, and said polypropylene resin composition has a crystallization rate of up to 35 seconds.
Claim 12
Dependent Claim 84 words
A process according to claim 1 or 2, wherein the polypropylene resin composition has a melt index of at least 20, and said polypropylene resin composition has a crystallization rate of up to 35 seconds, and said crystallization rate represents a value obtained by melting the polyprypelene resin composition, subjecting the polypropylene resin composition to isothermal crystallization at 130° C. and measuring the time required for crystallizing one-half of the total amount of resin to be crystallized by means of a differential scanning calorimeter.
Claim 13
Independent Claim 48 words
A method of preventing generation of deformities in a multilayer molded article comprised a skin and a thermoplastic resin, wherein a polypropylene resin composition having a crystallization rate of 45 seconds or less is used as the thermoplastic resin in the process for producing the multilayer molded article.
Claim 14
Independent Claim 48 words
A method of preventing generation of deformities in a multilayer molded article comprised a skin and a thermoplastic resin, wherein a polypropylene resin composition having a crystallization rate of 45 seconds or less is used as the thermoplastic resin in the process for producing the multilayer molded article.
Claim 15
Dependent Claim 69 words
A method according to claim 11, wherein the multilayer molded article is produced by the steps of: (1) feeding a skin material and a molten thermoplastic resin between a pair of upper and lower molds, (2) molding the molten resin in the molds whereby there is simultaneous adhering of the skin material to the surface of the molten resin, and (3) cooling the molten resin to solidify the same.
Claim 16
Dependent Claim 126 words
A method according to claim 11, wherein the multilayer molded article is produced by the steps of: (a) feeding a skin material between an open pair of upper and lower molds, (b) allowing the upper mold to close to a predetermined position, (c) feeding a molten thermoplastic resin between the skin material and the lower mold, (d) allowing the upper mold to further close while feeding the molten thermoplastic resin or after completing of feeding the predetermined amount of the molten thermoplastic resin, (e) closing and clamping the upper and lower molds together and molding the molten thermoplastic resin in the molds to thereby simultaneously adhere the skin material to the surface of the molded resin, and (f) cooling the molten resin to solidify the same.
Claim 17
Dependent Claim 36 words
A method according to claim 11, wherein said polypropylene resin contains a nucleating agent and for controlling the crystallization rate, and said nucleating agent is a metal salt of an organic acid or a sorbitol compound.
Claim 18
Dependent Claim 16 words
A method according to claim 14, wherein said nucleating agent is aluminum p-t-butylbensorbitol or 1,3,2,4-di-t-ethyl benzylidenesorbitol.
Claim 19
Dependent Claim 14 words
A method according to claim 15, wherein said nucleating agent and is aluminum p-t-butylbenzoate.

References Cited (Backward Citations)

US4404161A Cited
US5238640A Cited
JPH01235613A Cited
US5154872A Cited
JPH0280218A Cited
US4968474A Cited
US5122320A Cited
JPH04364910A Cited
US5352397A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-11-02 2002-05-04 2002-11-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-11-02 2006-05-04 2006-11-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-11-02 2010-05-04 2010-11-03 $7700.00 Window Closed / Lapsed

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