EP-4740918-A2 - LAMINATED SUBSTRATE

Abstract

The present invention provides a laminated substrate for use as an anti-fogging insert for an eye shield, more particularly for use as a heated anti-fogging insert for a visor or goggles.

Inventors

• EITE, Jason

Assignees

• Diamond Coatings Ltd

Dates

Publication Date

20260513

Application Date

20190319

Claims (15)

1. A laminated anti-fogging insert for an eye shield, comprising: f) a substrate which is a flexible transparent film; g) a first and second metal strip, which metal strips are applied to respective non-adjacent edges of the substrate; h) at least two electrical connectors independently positioned at one end of each of the first and second conductive metal strips; i) a conductive layer which partially overlaps the metal strips; and j) an index-matching layer.
2. . A laminated anti-fogging insert according to claim 1, wherein the index-matching layer is disposed on the conductive layer.
3. . A laminated anti-fogging insert according to claim 1 or claim 2, wherein the index-matching layer is directly disposed on the conductive layer.
4. . A laminated anti-fogging insert according to any preceding claim, wherein the index-matching layer is a chemical vapour deposited layer or physical vapour deposited layer.
5. . A laminated anti-fogging insert according to claim 1, wherein the conductive layer comprises a transparent conducting oxide (TCO).
6. . A laminated anti-fogging insert according to any preceding claim, wherein the conductive layer has a thickness of from 80 to 120 nm.
7. . A laminated anti-fogging insert according to any preceding claim, wherein the index-matching layer comprises a low refractive index material such as silicon oxide, magnesium fluoride and fluorinated polymers.
8. . A laminated anti-fogging insert according to any preceding claim, wherein the index-matching layer has a thickness of about 80 to 90 nm.
9. . A laminated anti-fogging insert according to any preceding claim, wherein the index-matching layer comprises silicon oxide and has a thickness of about 80 to 90 nm.
10. . A laminated anti-fogging insert according to any preceding claim, wherein the substrate is formed of a flexible transparent plastic selected from Polyethylene Terephthalate (PET), Polycarbonate (PC), Acrylic (PMMA), Cyclic Olefin Copolymer (COC) , Cyclic Olefin Polymer (COP), Thermoplastic polyurethane (TPU), Ethylene vinyl acetate (EVA), Polyvinylidene fluoride or polyvinylidene difluoride (PVDF), Ethylene tetrafluoroethylene (ETFE) and Polyethylene-naphthalate (PEN) film.
11. . An eye shield comprising a lens; a laminated anti-fogging insert as defined in any one of claims 1 to 10; and a first attachment means for attaching the laminated anti-fogging insert to the lens, thereby defining a sealed air gap between the lens and the insert.
12. . An eye shield according to claim 11, wherein the eye shield is selected from a protective helmet visor and protective goggles.
13. . A process for preparing a laminated anti-fogging insert or eye shield according to any one of claims 1 to 13, comprising: g) providing a substrate which is a flexible transparent film; h) optionally masking parts of the first layer; i) applying a first and second metal strip; j) applying a conductive layer; k) applying an index-matching layer; and l) optionally applying a first attachment means to the periphery of the laminated anti-fogging insert.
14. . A process according to claim 13, wherein the conductive layer and/or the index-matching layer are applied by chemical vapour deposition or physical vapour deposition.
15. . A kit comprising: d) a laminated anti-fogging insert according to any one of claims 1 to 10; e) a first attachment means; f) one or more electrical connectors; and g) optionally one or more batteries.

Description

The present invention relates to a laminated substrate for use as an anti-fogging insert for an eye shield, more particularly for use as a heated anti-fogging insert for a visor or goggles. BACKGROUND Protective helmets, such as for motorcycle or snowmobile riding, typically have transparent visors, or eye shields, and protective goggles for use when skiing, snowboarding, diving etc, are known to fog in certain weather conditions such as rain or cold weather, reducing visibility for the wearer. Pinlock Fog Free Systems® address the problem of fogging by the provision of a visor insert which comprises a moisture absorbing layer and a silicon seal. However, excessive moisture can cause this system to fail, resulting in visible drops or lines of water on the visor and a corresponding loss of visibility. US2008/0290081A1 discusses the use of a heater element formed of an etched metal form as an anti-fogging device, while US5,351,339 discusses the use of an electroconductive film. These known devices all have a high degree of reflection on the inside of the visor or goggles which can interfere with the user's field of vision. In particular, indium tin oxide (ITO), a commonly used transparent conductive oxide (TCO), has a refractive index of 2, resulting in high reflection for the user of such products. SUMMARY OF THE INVENTION The invention provides a laminated anti-fogging insert for an eye shield, comprising: a) a substrate which is a flexible transparent film;b) a first and second metal strip, which metal strips are applied to respective non-adjacent edges of the substrate;c) at least two electrical connectors independently positioned at one end of each of the first and second conductive metal strips;d) a conductive layer which partially overlaps the metal strips; ande) an index-matching layer. The invention further provides an eye shield comprising a lens and a laminated anti-fogging insert, which laminated anti-fogging device comprises: a) a substrate which is a flexible transparent film;b) a first and second metal strip, which metal strips are applied to respective non-adjacent edges of the substrate;c) at least two electrical connectors independently positioned at one end of each of the first and second conductive metal strips;d) a conductive layer which partially overlaps the metal strips;e) an index-matching layer; andf) a first attachment means for attaching the laminated anti-fogging insert to the lens, thereby defining a sealed air gap between the lens and the insert. The invention further provides a process for preparing a laminated anti-fogging insert or eye shield, comprising: a) providing a substrate which is a flexible transparent film;b) optionally masking parts of the first layer;c) applying a first and second metal strip;d) applying a conductive layer;e) applying an index-matching layer; andf) optionally applying a first attachment means to the periphery of the laminated anti-fogging insert. BRIEF DESCRIPTION OF DRAWINGS Figure 1 illustrates in cross-section the laminated anti-fogging insert of the invention.Figure 2 illustrates in cross-section means for attaching the laminated anti-fogging insert of the invention to an eye shield.Figure 3 illustrates in plan-view a preferred positioning of the electrical connectors at opposing ends of the first and second metal strips. DETAILED DESCRIPTION Figure 1 illustrates a laminated anti-fogging insert for an eye shield comprising a substrate which is a flexible transparent film (1), first and second metal strips (2), a conductive layer (3) which partially overlaps the metal strips, and an index matching layer (4). Figure 2 illustrates a laminated anti-fogging insert for an eye shield which further comprises a first attachment means (5) for attaching the laminated anti-fogging insert to the lens, thereby defining a sealed air gap between the lens and the insert; and formed supports (7) which are attached to the index matching layer (4) by a second attachment means (6) and which hold in place electrical connectors (8a, 8b - not shown) connected to the metal strips (2). Figure 3 illustrates a laminated anti-fogging insert for an eye shield wherein the electrical connectors (8a and 8b) are positioned at opposing ends of the first and second conductive metal strips. Accordingly, the invention is described by the following embodiments.; In embodiment 1, the invention provides a laminated anti-fogging insert for an eye shield, comprising: a) a substrate which is a flexible transparent film;b) a first and second metal strip, which metal strips are applied to respective non-adjacent edges of the substrate;c) at least two electrical connectors independently positioned at one end of each of the first and second conductive metal strips;d) a conductive layer which partially overlaps the metal strips; ande) an index-matching layer. In embodiment 2, the invention provides a laminated anti-fogging insert according to embodiment 1, wherein the substrate is formed of