WO1998047635A1

WO1998047635A1 - Composition for cleaning transparent hard surfaces and method of using same

Info

Publication number: WO1998047635A1
Application number: PCT/US1998/008158
Authority: WO
Inventors: Robert H. Black
Original assignee: Black Robert H
Priority date: 1997-04-24
Filing date: 1998-04-23
Publication date: 1998-10-29
Also published as: AU7254898A

Abstract

The invention relates to an aqueous composition for cleaning transparent hard surfaces, through which an image is visually observed by a user, such as eyeglasses, computer screens, mirrors, and the like, and a method of using the aqueous composition. The aqueous composition includes a non-ionic surfactant having an HLB of 13 or less, a volatile oxygenated solvent, and deionized or distilled water.

Description

COMPOSITION FOR CLEANING TRANSPARENT HARD SURFACES AND METHOD OF USING SAME

BACKGROUND OF THE INVENTION

Field of the Invention

The invention relates to an aqueous composition for cleaning transparent hard surfaces such as those of eyeglasses, computer screens, and mirrors, and a method of using same.

Description of the Related Art

Transparent hard surfaces, through which an image is to be visually observed by an individual user, such as those of eyeglasses, computer screens, and mirrors, readily accumulate deposits from airborne particulates, aerosols, fingers, eyelashes, etc., because these surfaces have a differential electric charge that attracts airborne particles and aerosols. For instance, computer screens attract airborne particles as a result of the electric charge developed by the cathode ray tube .

Eyeglasses have the added problem of being readily fogged from perspiration or from the humidity in the air. Perspiration causes fogging of eyeglasses because the air pocket formed by the eye socket and the eyeglasses traps the humid air from perspiration on one side of the glasses while the other side is being cooled by the ambient air. A similar phenomenon is observed on eyeglasses when the wearer moves from a cool environment into a warm humid environment where moisture from the humid air condenses on the eyeglasses and causes fogging. Likewise, mirrors in the bathroom are fogged up by the steam generated in showering or bathing.

As transparent hard surfaces such as those of glasses and computer screens readily accumulate deposits, these surfaces require frequent cleaning in order to maintain the ability to allow the user to see images clearly. Similarly, condensation on eyeglasses usually forces the user to wipe the eyeglasses to remove the moisture which sometimes compound the problem by smearing any accumulated airborne deposits, aerosols, etc., over the surfaces of the eyeglasses.

With eyeglasses, the use of soaps or liquid detergents commonly available in bathrooms and kitchens frequently leave an opaque residual film or smear on the eyeglasses which require further effort to clean. Commercially available cleaners for eyeglasses, however, generally contain water, anionic and/or cationic surfactants, and low boiling solvents. The surfactants help to loosen deposits and suspend them in the water, while the low boiling solvents help to remove grease deposits. Furthermore, the surfactants in conventional eyeglass cleaners are generally anionic and/or cationic surfactants and all have a high hydrophilic-lipophilie balance (HLB) number. Surfactants which are not removed upon wiping of the eyeglasses with tissues, paper towels, clothing, etc., align with the hydrophilic end of the surfactant molecule facing towards the surface of the eyeglasses and with the hydrophobic end facing away from the surface and exposed to the ambient air. At the present time, there is no acceptable product for cleaning transparent hard surfaces, such as those of eyeglasses, computer screens, and mirrors, which not only removes accumulated deposits, but also resists fogging and the accumulation of particulate and aerosol deposits on the treated surfaces.

SUMMARY OF THE INVENTION

It is accordingly an object of the present invention to overcome the deficiencies in the prior art, as noted above.

Another object of the invention is to provide a composition for cleaning transparent hard surfaces.

A further object of the invention is to provide a method of using the composition to clean transparent hard surfaces.

The present invention thus provides an aqueous non- smearing composition for cleaning transparent hard surfaces, through which an image is usually observed by a user, such as those of eyeglasses, computer screens and the like, and which includes a non-ionic surfactant having an HLB of 13.0 or less, a volatile oxygenated solvent, and deionized or distilled water. A method of using such an aqueous cleaning composition, whereby the treated transparent hard surfaces resist fogging and the accumulation of airborne deposits is also provided.

DETAILED DESCRIPTION OF THE INVENTION

The aqueous cleaning composition for transparent hard surfaces according to the present invention includes a non-ionic surfactant having an HLB of 13 or less, a volatile oxygenated solvent, and water having negligible amounts of metal ions and minerals. The volatile oxygenated solvent acts to help soften and loosen the deposits accumulated on the surface while the non-ionic surfactant provides detergent action, with the water helping to carry the deposits onto a clean soft fabric or fibrous tissue material, such as a tissue or cloth, used to wipe the treated surface. When the residual solution left on the surface evaporates after wiping with a tissue or cloth, a Langmuir Blodgett film composed of alternating layers of hydrophilic and hydrophobic surfactant ends is formed on the transparent hard surface, where the first layer on the treated surface has the hydrophilic surfactant end facing towards the surface.

A Langmuir Blodgett film is much thinner than about 1/4 the wavelength of visible light, and therefore appears to be completely transparent to the user. This film is also sufficiently hygroscopic so that the film conducts static electricity from the transparent hard surface to some support, frame, etc., which acts as an electrical sink. Thus, the transparent hard surface, which is kept electrically neutral, does not attract, but rather resists airborne deposits such as dust particles, aerosols, etc.

The Langmuir Blodgett surfactant film also prevents moisture from beading on the surface of eyeglasses and mirrors. Normally, eyeglasses become fogged with moisture when beads of water are deposited on the surface of the eyeglasses either due to humid air being trapped behind the eyeglasses as a result of perspiration, etc., or due to making a quick transition from a cool/cold environment or a warm humid environment (e.g., outdoors to indoors). The presence of the surfactant film formed by the aqueous composition of the present invention keeps the eyeglasses clear in situations where fogging of eyeglasses is a problem by keeping the surface of the eyeglasses clear and transparent so that the vision of the wearer is not disrupted. Likewise, mirrors are prevented from fogging up in the steamy environment of bathrooms .

Any of a number of non-ionic surfactants having an HLB of less than 13 can be suitably used in the aqueous cleaning composition of the present invention in the range of about 0.5 to 4% by volume, and preferably about 1 to 2% by volume. Preferably, the non-ionic surfactant has an HLB of 12.5 or less, and more preferably an HLB of 12.0 or less. Accordingly, non-ionic surfactants, such as but not limited to, ethoxylated alcohols, ethoxylated alkyphenols, sorbitan oleic esters, silicone copolymers, and mixtures thereof, can suitably be used in the aqueous cleaning composition of the present invention as long as the non-ionic surfactant has an HLB of 13 or less. Such a suitable non-ionic surfactant having an HLB of 13 or less would selectively form a Langmuir Blodgett surfactant film on the treated surface, thereby preventing the beading of water molecules to form condensation on the surface and providing electrical conductivity to the surface to resist airborne deposits. Non-ionic surfactants having a high HLB above 13 or anionic/cation surfactants used in conventional eyeglass cleaners do not form Langmuir Blodgett surfactant films with the advantageous properties described above. Non-ionic surfactants are also characterized by the cloud point. Excess surfactant exceeding the solubility limit in water forms a dispersion and exists in micelles below the cloud point . When the temperature is increased above the cloud point, the excess surfactant separates into a second phase. It will be appreciated that HLB can be experimentally obtained, or can be calculated or readily estimated from the cloud point or by other methods. The determination of both HLB and the cloud point of non-ionic surfactants are well within the knowledge and skill of ordinary artisans.

The solvent component of the aqueous cleaning composition may suitably be any volatile, non-toxic oxygenated solvent in the range of about 2 to 20% by volume, and more preferably in the range of about 5 to 15%, which improves the sheeting action of the aqueous cleaning composition. Any low molecular weight alcohol or low molecular weight glycol ether, such as ethyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, ethylene glycol, propylene glycol, glycerol, and the isopropyl or ethyl ether of ethylene glycol, can be used, although isopropyl alcohol is preferred. The water used in the aqueous cleaning composition must have negligible amounts of metal ions and minerals. Distilled water or deionized water is preferred.

The pH of the aqueous cleaning composition which can be adjusted as needed, is preferably in the range of about 4 to 7, more preferably in the range of about 4.5 to 5.5.

A preferred embodiment of the aqueous cleaning composition of the present invention in percent (%) by volume is as follows:

ANTAROX BL-225 surfactant 2% isopropyl alcohol 10% deionized water balance

The ANTAROX BL-225 non-ionic surfactant is a modified linear aliphatic polyether with an HLB of 12 and a cloud point of 21°C, which is commercially available from Rhone-Poulenc, Cranbury, NJ .

Another preferred embodiment of the aqueous cleaning composition of the present invention in percent (%) by volume is as follows:

Q2-5211 superwetting surfactant 1% isopropyl alcohol 10% deionized water balance

where Q2-5211 is a non-ionic silicone glycol copolymer commercially available from Dow Corning.

The method of cleaning transparent hard surfaces according to the present invention involves applying, preferably by spraying or misting, the aqueous cleaning composition of the present invention onto a transparent hard surface, and then wiping off the deposits from the surface so that a residual surfactant film, having the advantageous properties of resisting airborne deposits and the beading of water molecules from condensation, is formed on the surface. The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Claims

WHAT IS CLAIMED IS:

1. An aqueous cleaning composition for transparent hard surfaces, comprising:

0.5 to 4% by volume of a non-ionic surfactant having an HLB of 13 or less;

2 to 20% by volume of a volatile oxygenated solvent ; and water.

2. The aqueous cleaning composition according to claim 1, wherein said non-ionic surfactant has an HLB of 12.5 or less.

3. The aqueous cleaning composition according to claim 1, wherein said non-ionic surfactant has an HLB of 12 or less.

4. The aqueous cleaning composition according to claim 1, wherein said non-ionic surfactant is a superwetting surfactant .

5. The aqueous cleaning composition according to claim 1, wherein said non-ionic surfactant is selected from the group consisting of ethoxylated alcohols, ethoxylated alklyphenols, sorbitan oleic esters, silicone copolymers, and mixtures thereof .

6. The aqueous cleaning composition according to claim 1, wherein said water is distilled or deionized water.

7. The aqueous cleaning composition according to claim 1, wherein said volatile oxygenated solvent is selected from the group consisting of low molecular weight alcohols, low molecular weight glycol ethers, and mixtures thereof.

8. The aqueous cleaning composition according to claim 1, having a pH in a range of 4 to 7.

9. A method of cleaning transparent hard surfaces, comprising the steps of : applying an aqueous cleaning composition according to claim 1 to treat a transparent hard surface to be cleaned; wiping the treated transparent hard surface with a soft fabric or fibrous material to remove deposits; and forming a residual surfactant film on the transparent hard surface, whereby the transparent hard surface having the residual surfactant film thereon resists airborne deposits.

10. The method according to claim 9, wherein the transparent hard surface is a surface of eyeglasses.

11. The method according to claim 10, wherein the airborne deposits include moisture condensation.

12. The method according to claim 9, wherein the transparent hard surface is a surface of a mirror.

13. The method according to claim 12, wherein the airborne deposits include moisture condensation.

14. The method according to claim 9, wherein the transparent hard surface is a computer screen.