Attachable Photocatalytic Device

Abstract

A photocatalytic device includes one transparent or translucent carrier and at least one photocatalytic film. The carrier is in the form of a sheet with two opposite surface. At least one of the two surfaces of the carrier is at least partially coated with the photocatalytic film. The photocatalytic film is photocatalytic activated by visible light with wavelength>400 nm for providing the antibacterial functionality. In some situation, only the outer surface of the carrier is coated with the photocatalytic film. In other situation, only the inner surface of the carrier is coated with the photocatalytic film. There are situations where both surfaces of the carrier are coated with the photocatalytic film. The carrier has an attaching mechanism for attaching the carrier to the external solid object, and the carrier is attachable to and detachable from the external solid object hands of a user without using a tool.

Claims

1. A photocatalytic device, comprising: a transparent or translucent carrier; and at least one photocatalytic film, wherein: the carrier is in a form of a sheet with two opposite surfaces, at least one of the two surfaces of the carrier is at least partially coated with the photocatalytic film, the photocatalytic film is photocatalytic activated by visible light with wavelength greater than 400 nm, the carrier has an attaching mechanism capable of attaching to an external solid object, and the carrier is attachable to and detachable from the external solid object with hands of a user without using a tool.

2. The photocatalytic device of claim 1, wherein the carrier is made of a flexible material or a rigid material.

3. The photocatalytic device of claim 2, wherein the flexible material comprises plastics, and wherein the rigid material comprises glass.

4. The photocatalytic device of claim 1, wherein the photocatalytic film contains rhombus-shape anatase-type titanium dioxide (TiO.sub.2).

5. The photocatalytic device of claim 1, wherein the carrier is tinted to filter light in a predetermined wavelength range.

6. The photocatalytic device of claim 1, wherein the carrier is scratch-resistant.

7. The photocatalytic device of claim 1, wherein the carrier is shatter-resistant.

8. The photocatalytic device of claim 1, wherein the carrier comprises a heat insulator.

9. The photocatalytic device of claim 1, wherein the carrier comprises a solar cell.

10. The photocatalytic device of claim 1, wherein the attaching mechanism comprises an adhesive at least partially coated on a first surface of the two surfaces of the carrier to adhere the first surface of the carrier to the external solid object.

11. The photocatalytic device of claim 1, wherein the attaching mechanism comprises electrostatics between the carrier and the external solid object.

12. The photocatalytic device of claim 1, wherein the attaching mechanism comprises a weight of the carrier.

13. The photocatalytic device of claim 1, wherein the attaching mechanism comprises an elastic wrap around an edge of the carrier over the external solid object.

14. The photocatalytic device of claim 1, wherein the attaching mechanism comprises a Velcro between the carrier and the external solid object.

15. The photocatalytic device of claim 1, wherein the attaching mechanism comprises a physical or mechanical locking mechanism that locks the carrier to the external solid object.

16. The photocatalytic device of claim 1, wherein the attaching mechanism comprises wrapping of the carrier over the external solid object.

17. The photocatalytic device of claim 1, wherein the attaching mechanism involves having the carrier in a form of a bag that contains the external solid object.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are included to aid further understanding of the present disclosure, and are incorporated in and constitute a part of the present disclosure. The drawings illustrate a select number of embodiments of the present disclosure and, together with the detailed description below, serve to explain the principles of the present disclosure. It is appreciable that the drawings are not necessarily to scale, as some components may be shown to be out of proportion to size in actual implementation in order to clearly illustrate the concept of the present disclosure.

[0024] FIG. 1 schematically depicts a diagram of a photocatalytic device where the external solid object is a window and the attachable carrier is a window film.

[0025] FIG. 2 schematically depicts a diagram of a photocatalytic device where the external solid object is a touchscreen display and the attachable carrier is a screen protector.

[0026] FIG. 3 schematically depicts a diagram of a photocatalytic device where the external solid object is a computer keyboard and the attachable carrier is a keyboard protector with a locking mechanism.

[0027] FIG. 4 schematically depicts a diagram of a photocatalytic device where the external solid object is a food item and the attachable carrier is plastic food wrap coated with photocatalytic film.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Overview

[0028] Various implementations of the present disclosure and related inventive concepts are described below. It should be acknowledged, however, that the present disclosure is not limited to any particular manner of implementation, and that the various embodiments discussed explicitly herein are primarily for purposes of illustration. For example, the various concepts discussed herein may be suitably implemented in a variety of photocatalytic devices having different form factors.

[0029] The present disclosure discloses a photocatalytic device that one transparent or translucent carrier and a photocatalytic film. The carrier is in the form of a sheet with two surfaces At least one of the two surfaces of the carrier is at least partially coated with the photocatalytic film. The carrier has an attaching mechanism for attaching the carrier to an external solid object, and the carrier is attachable to and detachable from the external solid object with hands only, using no tools.

Example Implementations

[0030] The FIG. 1 is an embodiment of the photocatalytic device of the present disclosure where the attachable carrier 101 is in the form of a laminate window film and the external solid object is a window 102. The carrier 101 is made of polyethylene terephthalate (PET) and provides additional heat-insulation to the window 102. The outside surface of the carrier is coated with titanium dioxide film 103. There is no adhesive used on the inside surface of the carrier 101. The carrier is attached onto the window on its inside surface via electrostatics. By leveraging the large surface area of the window, this carrier provides a large photocatalytic active surface for killing any airborne microbial making contact to the titanium dioxide film on the carrier. This offers an effective means of antibacterial/antiviral protection for any rooms with large windows, such as classrooms, offices with large windows, and most residential rooms. The sunlight and the regular lighting fixtures or light bulbs all contain suitable visible light with wavelength>400 nm to activate the photocatalytic film coated on the carrier. UV light is not required. When the photocatalytic film on the carrier is worn off, the entire carrier (the window film) can then be easily detached and a new window film be attached.

[0031] It may be argued that the window film application above is obvious in view of the prior art technique. By tracing the history, photocatalyst has been introduced since 1996, and the window film has been used for decades as a winterization treatment on single-layer windows in cold weather zones. If it had been so obvious, then a photocatalyst coated window film would have been invented within the last 20 years. It is not the case. Therefore the novelty and the non-obviousness of the present disclosure as applied to the window film application is validated. Another key difference between the present disclosure and the prior art technique is that the prior art technique teaches to coat the photocatalytic film on the carrier, not under the carrier. As such, when the light shines on the device according to the prior art technique, the light shines through the photocatalytic film first before reaching the carrier. With the present disclosure, the light shines through the external solid object (the window) first, then through the carrier (the window film), and then finally through the photocatalytic film. This application is not taught by the prior art technique implicitly or explicitly.

[0032] The FIG. 2 is an embodiment of the photocatalytic device of the present disclosure where the carrier is in the form of a screen protector 201 and the external solid object is the touchscreen of a cellphone 202. The carrier is made of tempered glass for scratch-resistant and shatter-resistant. It is also tinted to filter out blue light for eye protection. The outside surface of the carrier is coated with titanium dioxide film 203, and the inside surface of the carrier is coated with an adhesive 204 for attaching the carrier to the cellphone screen. The light generated by the cellphone touchscreen provides suitable visible light with wavelength>400 nm to activate the photocatalytic film. No UV light is required. Rather than killing the airborne bacteria as shown in the window film application previously mentioned, the photocatalyst coated screen protector aims at killing the bacteria and the virus left by the user(s) when making contact on the screen protector with their fingers, or when it comes in contact with unsanitary surfaces, such as desks, bathrooms, public seating, counters. This prevents the transmission of diseases via a shared touchscreen by multiple users or via unsanitary surfaces. When the photocatalytic film is worn off due to heavy use, the user can easily replace it with a new photocatalyst coated screen protector.

[0033] A removable screen protector was first introduced by Herbert et al. in U.S. Pat. No. 3,418,426A in 1962 for TV screen. As mentioned previously, the photocatalyst has been introduced since 1996 by Soma et al. in U.S. Pat. No. 6,242,752B1 in 1996. Has it been obvious of making photocatalyst coated screen protector, there should be many such products, and there is none. Therefore the novelty and the non-obviousness of the present disclosure as applied to the touchscreen protector application is validated. Another key difference between the present disclosure and the prior art technique is that the prior art technique teaches to coat the photocatalytic film on of the carrier, not under the carrier. As such, when the light shines on the device, the light shines through the photocatalytic film first before reaching the carrier. With the present disclosure, the light shines through the external solid object (the touchscreen panel) first, then through the carrier (the screen protector), and then finally through the photocatalytic film. This application is not taught by the prior art technique implicitly or explicitly.

[0034] The FIG. 3 is an embodiment of the photocatalytic device of the present disclosure where the carrier is in the form of a keyboard protector 301 and the external solid object is a computer keyboard 302. The carrier is made of plastic material. The photocatalytic film 303 is coated on the top surface of the carrier. On each of the two short sides of the keyboard 304, there are two holes 305a and 305b. There are two knots (306a and 306b) on the inside of each of the two short edges of the carrier. The carrier is attached to the keyboard by pressing the two knots into the two holes of the keyboard. Other attaching mechanism such as an elastic wrap around the edge of the carrier, or a Velcro between the carrier and the keyboard, can also be used for attaching the carrier to the keyboard. Having the photocatalyst coated on the top surface of the carrier can inhibit effectively the transmission of the infectious diseases via a shared keyboard in the environment such as classrooms, public libraries, and hospitals. The photocatalytic film coated on the carrier may be photocatalytic activated by visible light with wavelength>400 nm. No UV light is required. When the photocatalytic film is worn off, the keyboard protector can be easily replaced with a new one. the prior art technique does not suggest implicitly or explicitly a physical or mechanical attaching mechanism for attaching his photocatalytic device to an external object.

[0035] The FIG. 4 is an embodiment of the photocatalytic device of the present disclosure where the carrier is in the form of a plastic food wrap 401 and the external solid object is a food item 402. The FIG. 4 shows the food item is ready to be wrapped by the carrier (the plastic food wrap). The photocatalytic film is coated on the inside surface of the carrier that will make contact with the food item. When a food item is exposed to air, any airborne microbial particles (bacteria, viruses, funguses) may land on the food item. When wrapping the food object with a regular plastic food wrap (without photocatalytic film), the bacteria, virus, and fungus on the surface of the food item could still grow. When wrapping the food object with a plastic food wrap coated with photocatalytic film, the photocatalyst can effectively inhibit the growth of bacteria, virus, and fungus on the surface of the food item, thus preventing bacteria and virus from growing and transmitting to the person consuming the food item, and preventing the food item from becoming stale by inhibiting the growth of the fungus. The photocatalytic film coated on the carrier may be photocatalytic activated by visible light with wavelength>400 nm. No UV light is required. The food item can be of any shape, and it can be raw or cooked or baked. This food preserving application by using a photocatalyst-coated food wrap is not taught by the prior art technique either implicitly or explicitly. In fact, photocatalytic coated food wrap has not existed for the last twenty years even though both photocatalyst and the plastic food wrap are available on the market. It may not be that obvious at all for making a photocatalytic coated plastic food wrap. In some medical applications, it is foreseeable to use a plastic wrap or a plastic bag that is coated with photocatalytic film on both surfaces of the wrap or bag for better antibacterial protection.

[0036] In both applications of plastic food wrap and plastic bag, the light shines through the carrier (the plastic food wrap or the bag) first, then shines through the photocatalytic film, and then finally reaching the food item or medical object in the wrap or bag. This is different from the prior art technique that the light shines through the photocatalytic film first and then the carrier. The prior art technique did not teach implicitly or explicitly the use of his photocatalytic device in such a way.

ADDITIONAL AND ALTERNATIVE IMPLEMENTATION NOTES

[0037] Although the techniques have been described in language specific to certain applications, it is to be understood that the appended claims are not necessarily limited to the specific features or applications described herein. Rather, the specific features and examples are disclosed as non-limiting exemplary forms of implementing such techniques.

[0038] As used in this application, the term or is intended to mean an inclusive or rather than an exclusive or. That is, unless specified otherwise or clear from context, X employs A or B is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then X employs A or B is satisfied under any of the foregoing instances. In addition, the articles a and an as used in this application and the appended claims should generally be construed to mean one or more, unless specified otherwise or clear from context to be directed to a singular form.