Coatings with low permeation of gases and vapors

• US 20040195960A1
• Filed: 02/18/2004
• Published: 10/07/2004
• Est. Priority Date: 08/20/2001
• Status: Active Grant

• Current Assignee: Beijing Xiaomi Mobile Software Co., Ltd. (Xiaomi Corp.)
• Original Assignee: Nova-Plasma Inc.
• Inventors: Czeremuszkin, Grzegorz, Latreche, Mohamed, Wertheimer, Michael Robert
• Granted Patent: US 7,074,501 B2
• Time in Patent Office: Days
• US Class Current: 313/504
• CPC Class Codes: C08J 7/0423 with at least one layer of inorganic material and at least one layer of a composition containing a polymer binder
• 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 7/046 Forming abrasion-resistant coatings; Forming surface-hardening coatings
• CPC Class Codes: C08J 7/048 Forming gas barrier coatings
• CPC Class Codes: C23C 16/0272 Deposition of sub-layers, e.g. to promote the adhesion of the main coating
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/402 Silicon dioxide
• CPC Class Codes: H10K 30/20 comprising organic-organic junctions, e.g. donor-acceptor junctions
• CPC Class Codes: H10K 30/30 comprising bulk heterojunctions, e.g. interpenetrating networks of donor and acceptor material domains
• CPC Class Codes: H10K 30/88 Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 39/10 Organic photovoltaic [PV] modules; Arrays of single organic PV cells
• CPC Class Codes: H10K 50/8445 multilayered coatings having a repetitive structure, e.g. having multiple organic-inorganic bilayers
• CPC Class Codes: H10K 77/10 Substrates, e.g. 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 428/917 Electroluminescent

Abstract

A multilayer structure has barrier properties for gases and vapors, for example oxygen and water vapor; the structure comprises: an organic substrate layer, and a multilayer permeation barrier thereon; the barrier comprises: a) a first inorganic coating contacting a surface of the substrate layer, and b) a first organic coating contacting a surface of the inorganic coating; the structure may be employed in a variety of articles where barrier properties are important especially in electronic articles such as organic light emitting diode devices where superior barrier characteristics over the life of the device are required.

Claims

1. An organic light emitting or photovoltaic device in which organic semi-conductors are encased in a barrier envelope, said envelope comprising a multilayer structure comprising:

i) an organic substrate layer, and

ii) a multilayer permeation barrier thereon, said barrier comprising;

a) a first inorganic coating contacting a surface of said substrate layer, and

b) a first organic coating contacting a surface of said first inorganic coating.

2. A device according to claim 1, wherein the inorganic coating is impermeable to gases, when formed as a continuous coating and exhibits discontinuity-controlled permeability with the occurrence of inadvertent discontinuities in the inorganic coating;

and said organic coating exhibits diffusion controlled permeation of water vapor and oxygen.

3. A device according to claim 1 wherein said coatings a) and b) form a first permeation barrier of said mutilayer permeation barrier, and said multilayer permeation barrier further comprises at least one inorganic coating and at least one organic coating, in alternating relationship with said coatings of said first permeation barrier.

4. A device according to claim 1 wherein said coatings a) and b) form a first permeation barrier of said mutilayer permeation barrier, and said multilayer permeation barrier further comprises a first plurality of inorganic coatings and a second plurality of organic coatings, in alternating relationship, with an inorganic coating of said first plurality contacting coating b).

5. A device according to claim 1 wherein said inorganic coating has a thickness of 1 nm to 1 μ

m.

6. A device according to claim 2 or wherein said inorganic coating has a thickness of 45 nm to 350 nm.

7. A device according to claim 1 wherein said organic coating has a thickness of 5 nm to 10 μ

m.

8. A device according to claim 2 wherein said organic coating has a thickness of 20 to 500 nm.

9. A device according to claim 3 wherein each inorganic coating has a thickness of 45 to 350 nm.

10. A device according to claim 4 wherein each organic coating has a thickness of 20 to 500 nm.

11. A multilayer structure according to claim 3, wherein each organic coating has a thickness of 20 to 500 nm, and at least one organic coating of said second permeation barrier has a thickness greater than 1 μ

m up to 10 μ

m.

12. A device according to claim 1 wherein said organic substrate has a thickness of 5 to 5000 μ

m.

13. A device according to claim 12, wherein the substrate is selected from the group consisting of:

a) single, multi-layer or coextruded plastic films;

b) plastic films having the surface modified by at least one of the following techniques;

corona discharge treatment, low or atmospheric pressure glow discharge, flame treatment and heat treatment, and a radiation treatment wherein the radiation is selected from the group consisting of UV, VUV, X-rays, gamma-rays, and particle radiation such as ion bombardment

c) plastic films having a surface coated with a functional coating selected from a hard-coating, an anti-scratch coating, an anti-abrasion coating, an anti-reflective coating, an anti-glare coating, a chemically-active coating, an oxygen scavenger coating, a desiccant coating, a UV-protective coating, and a colour-adjustment coating.

14. A device according to of claim 13 wherein the or each inorganic coating is completely or essentially made of an inorganic material which is selected from the group consisting of SiO₂, SiO_x, SiO_xC_y, Si₃N₄, Si_xN_yC_z, SiO_xN_y, TiO₂, TiO_x, ZrO₂, ZrO_x, Al₂O₃, SnO₂, In₂O₃, ITO, PbO, PbO₂, B₂O₃, P₂O₅, tantalum oxide, yttrium oxide, barium oxide, magnesium oxide, amorphous carbon, sulphur, selenium, magnesium fluoride, calcium fluoride, calcium oxide, mixtures thereof, or their alloys or compounds;

wherein x represents an integer ranging from 1 to 3, y represents a number ranging from 0.01 to 5 and z represents a number ranging from 0.01 to 5.

15. A device according to claim 14, wherein the or each organic coating is completely or essentially made of an organic material which is selected from the group consisting of plasma-deposited coatings obtained from mixtures containing at least one organic substance, gas or vapor at normal pressure, with or without contribution of inert or reactive gases, said organic substance being selected from:

hydrocarbons, organic compounds containing one or more heteroatoms, alcohols, ethers, esters, or their combinations, organosilicon compounds, and organometallic compounds.

16. A device according to claim 1 wherein the substrate is rigid.

17. A device according to claim 1 wherein the substrate is flexible.

18. A device according to claim 1 wherein the permeation-barrier-providing coating is transparent.

19. A device according to claims 1 having an oxygen permeation, measured by ASTM methods F1927 and D3985 which is lower than 2 cm³/m² day.

20. A device according to claims 1 having an oxygen permeation, measured by ASTM methods F1927 and D3985 which is lower than 0.01 cm³/m² day.

21. A device according to claim 1 wherein said multilayer barrier has hardness of less than 2 GPa.

22. A device according to claim 1 wherein said substrate has a smooth, flat surface in direct contact with said first inorganic coating.

24. An organic light emitting device in which light emitting diodes are encased in said barrier envelope, as defined in claim 1.

23. (Cancelled)

25. A process for producing an organic light emitting or photovoltaic device comprising preparing a multilayer permeation barrier structure by:

i) depositing an inorganic material on an organic substrate to form an inorganic coating in contact with a surface of said organic substrate;

ii) depositing an organic coating on said inorganic coating, and

iii) enveloping an organic semi-conductor for said device in an envelope which comprises said barrier structure.

26. A process according to claim 25, wherein said depositing in i) is by PECVD, CVD, PVD, evaporation, reactive evaporation, sputtering, reactive sputtering, cathodic or anodic arc evaporation or wet chemical (e.g. sol-gel), in partial vacuum, or at or above atmospheric pressure;

and said depositing in ii) is in partial vacuum, or at or above atmospheric pressure, using dip coating, spray coating, cast coating, sputtering, reactive sputtering, evaporation, reactive evaporation, PECVD, pyrolysis/condensation or pyrolysis/polymerization methods.

28. A process according to claim 25, wherein the depositing of inorganic material is carried out by using PECVD or PVD, in partial vacuum;

and the depositing of organic material is carried out using PECVD or pyrolysis/polymerisation method in partial vacuum.

27. (Cancelled)