Biaxially stretched laminated polyester film, infrared light shielding structure for laminated glass composed of the same, and laminated glass composed of the same

• US 10,241,248 B2
• Filed: 11/28/2012
• Issued: 03/26/2019
• Est. Priority Date: 11/29/2011
• Status: Active Grant

• Current Assignee: Teijin DuPont Films Japan Ltd. (Teijin Limited)
• Original Assignee: Teijin DuPont Films Japan Ltd. (Teijin Limited)
• Inventors: Yoshimura, Tomoka, Oya, Taro, Ono, Mitsumasa, Yoshida, Tetsuo
• Primary Examiner(s): Allen, Stephone B
• Assistant Examiner(s): Booher, Adam W
• Application Number:
  US14/360,083
• Publication Number:
  US 20140327958A1
• Time in Patent Office: 2,309 Days
• CPC Class Codes: B32B 15/08 of synthetic resin
• CPC Class Codes: B32B 15/09 comprising polyesters
• CPC Class Codes: B32B 17/10005 laminated safety glass or glazing
• CPC Class Codes: B32B 17/10174 Coatings of a metallic or dielectric material on a constituent layer of glass or polymer
• CPC Class Codes: B32B 17/10678 comprising UV absorbers or stabilizers, e.g. antioxidants
• CPC Class Codes: B32B 17/10743 containing acrylate (co)polymers or salts thereof
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: B32B 17/10788 containing ethylene vinylacetate
• CPC Class Codes: B32B 2250/05 5 or more layers
• CPC Class Codes: B32B 2250/244 All polymers belonging to those covered by group B32B27/36
• CPC Class Codes: B32B 2250/42 Alternating layers, e.g. ABAB(C), AABBAABB(C)
• CPC Class Codes: B32B 2255/10 on synthetic resin layer or on natural or synthetic rubber layer
• CPC Class Codes: B32B 2255/205 Metallic coating
• CPC Class Codes: B32B 2255/26 Polymeric coating
• CPC Class Codes: B32B 2307/30 having particular thermal properties
• CPC Class Codes: B32B 2307/306 Resistant to heat
• CPC Class Codes: B32B 2307/416 Reflective
• CPC Class Codes: B32B 2307/418 Refractive
• CPC Class Codes: B32B 2307/518 bi-axially
• CPC Class Codes: B32B 2307/54 Yield strength; Tensile strength
• CPC Class Codes: B32B 2307/732 : Dimensional properties
• CPC Class Codes: B32B 2367/00 : Polyesters, e.g. PET, i.e. polyethylene terephthalate
• CPC Class Codes: B32B 2551/00 : Optical elements
• CPC Class Codes: B32B 2605/006 : Transparent parts other than made from inorganic glass, e.g. polycarbonate glazings
• CPC Class Codes: B32B 27/08 : of synthetic resin
• CPC Class Codes: B32B 27/18 : characterised by the use of special additives
• CPC Class Codes: B32B 27/306 : comprising vinyl acetate or vinyl alcohol (co)polymers
• CPC Class Codes: B32B 27/32 : comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 27/36 : comprising polyesters
• CPC Class Codes: B32B 7/023 : Optical properties
• CPC Class Codes: B32B 7/027 : Thermal properties
• CPC Class Codes: B32B 7/03 : with respect to the orientation of features direction of fibres or filaments B32B5/12
• CPC Class Codes: B32B 7/05 : the layers not being connected over the whole surface, e.g. discontinuous connection or patterned connection using interposed adhesives or bonding materials applied in spaced arrangements B32B7/14
• CPC Class Codes: B32B 7/12 : using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: B60J 3/007 : Sunglare reduction by coatings, interposed foils in laminar windows, or permanent screens layered glass products B32B17/00; process of coating windows C03C17/00
• CPC Class Codes: G02B 5/282 : reflecting for infrared and transparent for visible light, e.g. heat reflectors, laser protection
• CPC Class Codes: Y10T 428/24975 : No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/265 : 1 mil or less
• CPC Class Codes: Y10T 428/31616 : Next to polyester [e.g., alkyd]
• CPC Class Codes: Y10T 428/3163 : Next to acetal of polymerized unsaturated alcohol [e.g., formal butyral, etc.]
• CPC Class Codes: Y10T 428/31786 : Of polyester [e.g., alkyd, etc.]

Abstract

Provided are a biaxially stretched laminated polyester film and a laminated glass composed of the same. Specifically, the invention is achieved by a biaxially stretched laminated polyester film including 51 layers or more in total, in which a first layer and a second layer are alternately laminated, wherein a polyester (A) constituting the first layer is polyethylene-2,6-naphthalenedicarboxylate; a polyester (B) constituting the second layer is a polyester containing at least one of an ethylene terephthalate component and an ethylene naphthalene dicarboxylate component; an average reflectance within a wavelength range of 400 to 750 nm is not more than 25%; an average reflectance within a wavelength range of 800 to 1,200 nm is 50% or more; and a Young'"'"'s modulus of the film at 90° C. is 2,400 MPa or more in at least one direction of the longitudinal direction and the lateral direction of the film.

Claims

1. A biaxially stretched laminated polyester film comprising 51 layers or more in total, in which a first layer and a second layer are alternately laminated, which is characterized in that a polyester (A) constituting the first layer is polyethylene-2,6-naphthalenedicarboxylate;

a polyester (B) constituting the second layer is a polyester containing at least one of an ethylene terephthalate component and an ethylene naphthalene dicarboxylate component;

an average reflectance within a wavelength range of 400 to 750 nm is not more than 25%;

an average reflectance within a wavelength range of 800 to 1,200 nm is 50% or more; and

a Young'"'"'s modulus of the film at 90°

C. is 2,400 MPa or more in at least one direction of the longitudinal direction and the lateral direction of the film,

wherein the biaxially stretched laminated polyester film has a single-layered protective layer composed of a polymer having a glass transition temperature of 90°

C. or higher and having a thickness of 5 μ

m or more and not more than 20 μ

m on both sides of a laminated structure portion (I) in which the first layer and the second layer are alternately laminated,

wherein the single-layered protective layer and the laminated structure portion (I) are directly attached,

wherein the polymer of the protective layer includes polyethylene naphthalate, polystyrene, polyphenylene sulfide, polyether sulfone, or polyphenylene oxide.

2. The biaxially stretched laminated polyester film according to claim 1, wherein the polyester (B) constituting the second layer is a polyester containing 50% by mole or more and not more than 95% by mole of an ethylene terephthalate component on the basis of the whole recurring units.

3. The biaxially stretched laminated polyester film according to claim 2, wherein the polyester (B) constituting the second layer is copolymerized polyethylene terephthalate having a glass transition temperature of lower than 90°

C.

4. The biaxially stretched laminated polyester film according to claim 1, wherein the polyester (B) constituting the second layer is copolymerized polyethylene terephthalate having a glass transition temperature of lower than 90°

C.

5. The biaxially stretched laminated polyester film according to claim 1, wherein the polyester (B) constituting the second layer is a polyester having a glass transition temperature of 90°

C. or higher.

6. The biaxially stretched laminated polyester film according to claim 5, wherein the polyester (B) constituting the second layer is a polyester containing 30% by mole or more and not more than 90% by mole of an ethylene naphthalene dicarboxylate component on the basis of the whole recurring units.

7. The biaxially stretched laminated polyester film according to claim 1, wherein the polyester (A) constituting the first layer is polyethylene-2,6-naphthalenedicaboxylate having a copolymerization amount of not more than 8% by mole on the basis of the whole recurring units.

8. The biaxially stretched laminated polyester film according to claim 1, having at least one layer containing an ultraviolet light absorber.

9. The biaxially stretched laminated polyester film according to claim 8, wherein the ultraviolet light absorber has an extinction coefficient ε

at a wavelength of 380 nm of 2 or more.

10. The biaxially stretched laminated polyester film according to claim 9, wherein an average light transmittance within a wavelength range of 300 nm or more and less than 400 nm is not more than 10%.

11. The biaxially stretched laminated polyester film according to claim 8, wherein an average light transmittance within a wavelength range of 300 nm or more and less than 400 nm is not more than 10%.

12. The biaxially stretched laminated polyester film according to claim 1, which is used for shielding of heat rays.

13. The biaxially stretched laminated polyester film according to claim 1, which is used for laminated glass.

14. The biaxially stretched laminated polyester film according to claim 1, wherein a coating layer having a refractive index of 1.60 to 1.63 and a thickness of 0.05 to 0.2 is provided on at least one surface of the biaxially stretched laminated polyester film having the laminated structure portion (I).

15. An infrared light shielding structure for laminated glass comprising the biaxially stretched laminated polyester film according to claim 1 having a laminate of a metal and/or a metal oxide laminated on one surface thereof, wherein in the biaxially stretched laminated polyester film, a thickness of the protective layer on the side coming into contact with the laminate of a metal and/or a metal oxide is 5 μ

m or more and not more than 20 μ

m;

the laminate of a metal and/or a metal oxide has a laminated structure (II) in which a low-refractive index layer and a high-refractive index layer are alternately laminated; and

the infrared light shielding structure for laminated glass has an average reflectance in a wavelength range of 400 to 750 nm of not more than 30%, an average reflectance in a wavelength range of 800 to 1,200 nm of 50% or more, and an average reflectance in a wavelength range of 1,200 to 2,100 nm of 50% or more.

16. A laminated glass comprising two glass sheets having the infrared light shielding structure for laminated glass according to claim 15 sandwiched therebetween via a resin layer composed of at least one member selected from an ethylene-vinyl acetate copolymer, polyvinyl butyral, and an ionomer resin.

17. A laminated glass comprising two glass sheets having the biaxially stretched laminated polyester film according to claim 1 sandwiched therebetween via a resin layer composed of at least one member selected from an ethylene-vinyl acetate copolymer, polyvinyl butyral, and an ionomer resin.

18. The biaxially stretched laminated polyester film according to claim 1, wherein the polymer of the protective layer is polyethylene-2,6-naphthalate which is the same as a polymer of the first layer.

19. The biaxially stretched laminated polyester film according to claim 1, wherein the protective layer consists of the polymer having a glass transition temperature of 90°

C. or higher.