Coated polymeric substrates having improved surface smoothness suitable for use in flexible electronic and opto-electronic devices

• US 7,641,957 B2
• Filed: 03/19/2003
• Issued: 01/05/2010
• Est. Priority Date: 04/12/2002
• Status: Active Grant

• Current Assignee: DuPont Performance Elastomers L (Bristol-Myers Squibb Company)
• Original Assignee: DuPont Performance Elastomers L (Bristol-Myers Squibb Company)
• Inventors: Rakos, Karl, Eveson, Robert William, Robinson, Julian Neal
• Primary Examiner(s): Chen; Vivian
• Application Number:
  US10/510,084
• Publication Number:
  US 20050238871A1
• Time in Patent Office: 2,484 Days
• Field of Search: None
• US Class Current: 428/141
• CPC Class Codes: C08J 2367/02 Polyesters derived from dicarboxylic acids and dihydroxy compounds; C08J2367/06 takes precedence
• CPC Class Codes: C08J 2483/00 Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen, or carbon only; Derivatives of such polymers
• CPC Class Codes: C08J 7/0427 with only one layer of a composition containing a polymer binder with more layers C08J7/042
• CPC Class Codes: C08J 7/043 Improving the adhesiveness of the coatings per se, e.g. forming primers adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50
• CPC Class Codes: C08J 7/044 Forming conductive coatings; Forming coatings having anti-static properties
• CPC Class Codes: C08J 7/048 Forming gas barrier coatings
• CPC Class Codes: C08L 2666/54 Inorganic substances
• CPC Class Codes: C09D 183/04 Polysiloxanes
• CPC Class Codes: C09K 2323/033 Silicon compound, e.g. glass or organosilicon
• CPC Class Codes: C09K 2323/06 Substrate layer characterised by chemical composition
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: H10K 50/80 Constructional details
• CPC Class Codes: H10K 71/10 Deposition of organic active material
• CPC Class Codes: H10K 77/111 Flexible substrates
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10S 428/91 Product with molecular orientation
• CPC Class Codes: Y10T 428/1379 Contains vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/24372 Particulate matter
• CPC Class Codes: Y10T 428/24421 : Silicon containing
• CPC Class Codes: Y10T 428/25 : Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/259 : Silicic material
• CPC Class Codes: Y10T 428/26 : Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
• CPC Class Codes: Y10T 428/269 : including synthetic resin or polymer layer or component
• CPC Class Codes: Y10T 428/31663 : As siloxane, silicone or silane
• CPC Class Codes: Y10T 428/31786 : Of polyester [e.g., alkyd, etc.]

Abstract

The use of a coating composition comprising: (a) from about 5 to about 50 weight percent solids, the solids comprising from about 10 to about 70 weight percent silica and from about 90 to about 30 weight percent of a partially polymerized organic silanol of the general formula RSi(OH)₃, wherein R is selected from methyl and up to about 40% of a group selected from the group consisting of vinyl, phenyl, gamma-glycidoxypropyl, and gamma-methacryloxypropyl, and (b) from about 95 to about 50 weight percent solvent, the solvent comprising from about 10 to about 90 weight percent water and from about 90 to about 10 weight percent lower aliphatic alcohol, wherein the coating composition has a pH of from about 3.0 to about 8.0, for the purpose of improving the surface smoothness of a polymeric substrate, particularly a heat-stabilised, heat-set, oriented polyester substrate, and use of said coated substrate in the manufacture of an electronic or optoelectronic device containing a conjugated conductive polymer.

Claims

1. A method of improving the surface smoothness of a polymeric substrate, comprising disposing a coating layer on a surface of the polymeric substrate by a process comprising applying to a surface of the polymeric substrate a coating composition comprising:

(a) from about 5 to about 50 weight percent solids, the solids comprising from about 10 to about 70 weight percent silica and from about 90 to about 30 weight percent of a partially polymerized organic silanol of the general formula RSi(OH)₃, wherein R is selected from methyl and up to about 40% of the R groups are a group selected from the group consisting of vinyl, phenyl, gamma-glycidoxypropyl, and gamma-methacryloxypropyl, and

(b) from about 95 to about 50 weight percent solvent, the solvent comprising from about 10 to about 90 weight percent water and from about 90 to about 10 weight percent lower aliphatic alcohol,

wherein the coating composition has a pH of from about 3.0 to about 8.0 and wherein a surface of said coating layer exhibits an Ra value of less than 0.6 nm, and/or an Rq value of less than 0.8 nm.

2. The method according to claim 1 wherein the pH of the coating composition is in the range 3.0 to 6.5.

3. The method according to claim 1 wherein the pH of the coating composition is about 6.0.

4. The method according to claim 1 wherein said polymeric substrate is a polyester film.

5. The method according to claim 4 wherein said polymeric substrate is a poly(ethylene naphthalate) or poly(ethylene terephthalate) film.

6. The method according to claim 4 wherein the polyester is derived from 2,6-naphthalenedicarboxylic acid.

7. The method according to claim 6 wherein the polyester is poly(ethylene naphthalate) having an intrinsic viscosity of 0.5-1.5.

8. The method according to claim 1 wherein said polymeric substrate is a heat-stabilised, heat-set, oriented film.

9. The method according to claim 1 wherein said polymeric substrate has a shrinkage at 30 mins at 230°

C. of less than 1%.

10. The method according to claim 1 wherein said polymeric substrate has a residual dimensional change Δ

L_r measured at 25°

C. before and after heating the substrate from 8°

C. to 200°

C. and then cooling to 8°

C., of less than 0.75% of the original dimension.

11. The method according to claim 1 wherein said polymeric substrate is a heat-stabilised, heat-set, oriented film comprising poly(ethylene naphthalate) film having a coefficient of linear thermal expansion (CLTE) within the temperature range from −

40°

C. to +100°

C. of less than 40×

10<sup>−

6</sup>/°

C.

12. The method according to claim 1 wherein said substrate has a % of scattered visible light (haze) of <

1.5%.

13. The method according to claim 1 wherein said substrate is a heat-stabilised biaxially oriented film.

14. The method according to claim 1 wherein the substrate is part of an electronic or opto-electronic device containing a conjugated conductive polymer.

15. The method according to claim 14 wherein said electronic or opto-electronic device is an electroluminescent display device.

16. The method according to claim 14 wherein said electronic or opto-electronic device is an organic light emitting display (OLED) device.

17. A composite film comprising a heat-stabilised, heat-set, oriented polyester substrate and a coating layer, wherein the coating layer is derived from the coating composition recited in claim 1, and wherein a surface of said coating layer exhibits an Ra value of less than 0.6 nm, and/or an Rq value of less than 0.8 nm.

18. The composite film according to claim 17 wherein said polyester substrate is a poly(ethylene naphthalate) film.

19. The composite film according to claim 17 wherein said polyester substrate exhibits one or more of the following characteristics:

(i) a shrinkage at 30 mins at 230°

C. of less than 1%; and

/or

(ii) a residual dimensional change Δ

L_r measured at 25°

C. before and after heating the polyester substrate from 8°

C. to 200°

C. and then cooling to 8°

C., of less than 0.75% of the original dimension; and

/or

(iii) a coefficient of linear thermal expansion (CLTE) within the temperature range from −

40°

C. to +100°

C. of less than 40×

10<sup>−

6</sup>/°

C.; and

/or

(iv) a % of scattered visible light (haze) of <

1.5%.

20. The composite film according to claim 17 further comprising a barrier layer.

21. The composite film according to claim 20 which exhibits a water vapour transmission rate of less than 10⁻

6g/m^2/day and/or an oxygen transmission rate of less than 10<sup>−

5</sup>/mL/m²/day.