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US5948544A Expired / Lapsed US ⏱️ 0.0 years remaining

Polyester multilayer sheet having excellent impact strength and weatherability, and a process for preparing the same

Assignee: Kolon Industries Inc
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Filing: 1998-01-20
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Granted: 1999-09-07
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Expires: 2018-01-20
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Abstract

Abstract The present invention relates to a polyester multilayer sheet having excellent impact strength and weatherability, and relates to a process for preparing the same. The present invention relates to coextrude more than 2 kinds of copolyester resins, composed of 5-99 mol % of ethyleneterephthalate and 1-95 mol % of ethylenenaphthalate or ethyleneisophthalate, having at least 0.005 dl/g of inherent viscosity difference each others, on 3-7 layers of multilayer sheet which had been arrayed by turns with high viscosity resin and low viscosity resin, and its outer layer has the higher inherent viscosity than the inner layer. Polyester multilayer sheet of the present invention is suitable for window glass substitute of building, transparent agricultural intercepting material and clothing material.

Inventors

  • 👤 Kyeong Ah Kim
  • 👤 Young Bum Kim
  • 👤 Young Seok Kim
  • 👤 Yong Cheol Shin
  • 👤 Boung Kun Son

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 21:34
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/36; B32B2270/00; B32B2307/00; B32B2307/40; B32B2307/412; B32B2367/00; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31786

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 75 words
A transparent polyester multilayer sheet, having excellent impact strength and weatherability, obtained by a process comprising: coextruding more than 3 layers of sheets using at least two separate kinds of copolyester resin which are composed of 5-99 mol % of ethyleneterephthalate and 1-95 mol % of ethylenenaphthalate or ethyleneisophthalate and have at least 0.05 dl/g difference in inherent viscosity between adjacent layers, wherein an outer layer has higher inherent viscosity than the adjacent inner layer.
Claim 2
Dependent Claim 75 words
A transparent polyester multilayer sheet, having excellent impact strength and weatherability, obtained by a process comprising: coextruding more than 3 layers of sheets using at least two separate kinds of copolyester resin which are composed of 5-99 mol % of ethyleneterephthalate and 1-95 mol % of ethylenenaphthalate or ethyleneisophthalate and have at least 0.05 dl/g difference in inherent viscosity between adjacent layers, wherein an outer layer has higher inherent viscosity than the adjacent inner layer.
Claim 3
Dependent Claim 24 words
The polyester multilayer sheet of claim 1, wherein the constitution ingredients and copolymerization ratios of the resins which compose each layer are the same.
Claim 4
Dependent Claim 23 words
The polyester multilayer sheet of claim 1, wherein the constitution ingredients and copolymerization ratios of the resins which compose each layer are different.
Claim 5
Dependent Claim 26 words
The polyester multilayer sheet of claim 1, wherein the copolymerized polyester resins are composed of 85-99 mol % ethyleneterephthalate and 1-15 mol % ethylenenaphthalate or ethyleneisophthalate.
Claim 6
Dependent Claim 18 words
The polyester multilayer sheet of claim 1, wherein the thickness of said polyester multilayer sheet is 2-10 mm.
Claim 7
Dependent Claim 17 words
The polyester multilayer sheet of claim 1, wherein the polyester multilayer sheet is composed of 3-7 layers.
Claim 8
Dependent Claim 37 words
The polyester multilayer sheet of claim 1, which has a thickness of 3 mm, its visible light transmittance is over 85%, and its protection ratio of UV light of wavelength less than 365 nanometers is over 85%.
Claim 9
Dependent Claim 86 words
A process for preparing transparent polyester multilayer sheet having excellent impact strength and weatherability, comprising: coextruding more than two separate kinds of copolyester resins, composed of 5-99 mol % of ethyleneterephthalate and 1-95 mol % of ethylenenaphthalate or ethyleneisophthalate, and having at least 0.005 dl/g difference in inherent viscosity between adjacent layers of the multilayer sheet, said coextruded layers being arrayed in turn by high inherent viscosity resin and low inherent viscosity resin, wherein an outer layer has higher inherent viscosity than the adjacent inner layer.
Claim 10
Dependent Claim 86 words
A process for preparing transparent polyester multilayer sheet having excellent impact strength and weatherability, comprising: coextruding more than two separate kinds of copolyester resins, composed of 5-99 mol % of ethyleneterephthalate and 1-95 mol % of ethylenenaphthalate or ethyleneisophthalate, and having at least 0.005 dl/g difference in inherent viscosity between adjacent layers of the multilayer sheet, said coextruded layers being arrayed in turn by high inherent viscosity resin and low inherent viscosity resin, wherein an outer layer has higher inherent viscosity than the adjacent inner layer.
Claim 11
Dependent Claim 27 words
The process for preparing polyester multilayer sheet of claim 8, wherein the constitution ingredients and copolymerization ratios of the resins which compose each layer are the same.
Claim 12
Dependent Claim 25 words
The process for preparing polyester multilayer sheet of claim 8, wherein the constitution ingredients and copolymerization ratios of resins which compose each layer are different.
Claim 13
Dependent Claim 30 words
The process for preparing polyester multilayer sheet of claim 8, wherein the copolyester resins are composed of 85-99 mol % of ethyleneterephthalate and 1-15 mol % of ethylenenaphthalate or ethyleneisophthalate.

References Cited (Backward Citations)

US5061565A Cited
US5458965A Cited
US5392986A Cited
US5753377A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-09-06 2003-03-08 2003-09-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-09-06 2007-03-08 2007-09-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-09-06 2011-03-08 2011-09-07 $7700.00 Window Closed / Lapsed

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