BE1029059A1 - Spray against fogging of glasses - Google Patents

Abstract

The present invention relates to an anti-vapor formulation for preventing vapor formation on a surface, wherein the anti-vapor formulation is a liquid based on an aqueous solution comprising a combination of 3-[hydroxy(poluethyleneoxy)propyl]heptamethyltrisiloxane and polydimethylsiloxane, wherein 3 -[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane has a concentration lower than 15% w/w and polydimethylsiloxane has a concentration between 1% and 5% w/w. The present invention also further relates to the use of the aforementioned anti-vapor formulation for forming a coating on a surface to prevent vapor formation on that surface and a kit comprising the aforementioned anti-vapor formulation and a microfiber cloth.

Description

SPRAY AGAINST DAMPING GLASSES

TECHNICAL FIELD The invention relates to an anti-vapor formulation for preventing vapor formation on a surface. The invention also relates to the use of said anti-vapor formulation for forming a coating on a surface and a kit comprising said anti-vapor formulation.

BACKGROUND ART Fogging of (safety) glasses and face masks is a common problem. This can be very annoying and even dangerous. For example, fogging of spectacle lenses greatly reduces vision, which can lead to dangerous situations. But not only glasses and face masks can be subject to vapor formation, other surfaces (think of mirrors, the screen of a smartphone, camera lenses, etc.) can also be affected by vapor under certain circumstances.

Fogging of surfaces can be reduced by treating these surfaces with a coating. This can be a permanent coating or a temporary coating. These coatings are already known and are often based on the application of a hydrophilic surfactant to the surface. As a result, the condensation droplets formed on the surface by vapor formation will form a small contact angle with the surface and the refraction of the light (and the associated decrease in visibility) will be minimized.

US3865619A discloses forming an anti-fog coating on an optical surface by applying a hydrophilic resin.

Also US9500860 describes an optical component (e.g. a spectacle lens) with a permanent hydrophilic anti-fog coating.

However, these permanent coatings have the disadvantage that they are often not scratch-resistant and that they are sensitive to temperature differences, which can damage them. Often the maximum temperature that a permanent coating can tolerate is about 80 °C, so like glasses in boiling falls (this can happen to cooks, for example), there is a good chance that the coating will not survive. If a permanent coating has been damaged, it is sometimes possible to remove it completely. In addition, it is technically very difficult to renew a permanent coating. Another problem with these already known coatings is that they are hydrophilic in nature. Such formulations are often incompatible with anti-reflective lenses, so they do not prevent fogging of the lenses.

The present invention aims to find a solution to at least some of the above-mentioned problems.

SUMMARY OF THE INVENTION The invention relates to an anti-vapor formulation according to claim 1. More particularly, the present invention describes an anti-vapor formulation for preventing vapor formation on a surface, wherein the anti-vapor formulation is a liquid based on an aqueous solution comprising a combination of 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane and polydimethylsiloxane, wherein 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane has a concentration below 15% w/w and polydimethylsiloxane has a concentration between 1% and 5 % w/w. Preferred embodiments of this anti-vapor formulation are set forth in claims 2 to 8.

In a second aspect, the invention relates to the use of said anti-vapor formulation according to claim 9. More particularly, the present invention describes the use of said anti-vapor formulation to form a coating on a surface to prevent vapor formation on that surface. surface. Preferred embodiments of this use are set forth in claims 10 to 14.

In a final aspect, the invention relates to a kit comprising said anti-vapor formulation and a microfibre cloth according to claim 15.

DETAILED DESCRIPTION There is a need for a non-permanent anti-fog formulation that can also be applied without problems to hydrophobic surfaces, such as certain anti-reflective lenses. The present invention offers a solution for this. Unless otherwise defined, all terms used in the description of the invention, including technical and scientific terms, have the meaning as generally understood by those skilled in the art of the invention. For a better assessment of the description of the invention, the following terms are explicitly explained. “A”, “the” and “the” refer to both the singular and the plural in this document unless the context clearly implies otherwise. For example, “a segment” means one or more than one segment. When "about" or "around" in this document is used with a measurable quantity, a parameter, a time or moment, etc., variations of +/-20% or less, preferably +/-10% or less, more preferably +/-5% or less, even more preferably +/-1% or less, and even more preferably +/-0.1% or less than and of the quoted value, to the extent that such variations of applicable to the invention described. However, this should be understood to mean that the value of the quantity using the term “approximately” or “around” is itself specifically disclosed.

The terms “comprise”, “comprising”, “consist of”, “consisting of”, “include”, “contain”, “containing”, “include”, “comprising”, “contain”, “include” are synonyms and are inclusive or open terms designating the presence of the following, and which do not exclude or preclude the presence of other components, features, elements, members, steps known from or described in the art. The “refractive index” of a medium refers in this document to the relationship between the phase speed of light in vacuum and the phase speed of light in that medium. Differences in refractive index play a role in, among other things, the phenomenon of refraction. A ray of light passing through the interface of two media is refracted if the speeds of light in the two media differ.

“Hydrophobic substances or materials” in this document refers to substances or materials that are water repellent or do not mix or mix very poorly with water.

Hydrophobic literally means 'water-fearing'. The cause of hydrophobia lies at the molecular level, Water is a polar compound that is attracted to other polar compounds.

There is no such molecular attraction between water and nonpolar compounds: these compounds are called hydrophobic.

Substances or materials that do show these interactions are called “hydrophilic”, “Surface tension” in this document refers to the physical phenomenon in which the surface of a liquid at a liquid-gas transition behaves as a resilient layer.

Van der Waals forces between molecules in the liquid phase cause this surface tension.

Loose droplets become spherical as much as possible.

The surface tension of water is further increased because water molecules form hydrogen bonds among themselves,

Citing numerical intervals through the endpoints includes all integers, fractions and/or real numbers between the endpoints, including these endpoints. Vapor formation on a surface occurs when gaseous water molecules make a phase transition to a liquid.

This can happen, for example, when the surface moves from a cold to a warm environment or when the surface comes into contact with a source of warm air with a relatively high degree of humidity.

This causes condensation droplets to form on the surface. These droplets prevent the light from propagating. This decrease in transmission is accompanied by an increase in the refractive index of the light, which reduces the transparency of the surface.

Fogging of surfaces can be reduced by treating these surfaces with a coating.

Such coatings are already known and are often based on the application of a hydrophilic surfactant to the surface.

As a result, the condensation droplets formed on the surface will form a small contact angle with the surface and the refraction of the light (and the associated decrease in visibility) will be minimized.

However, often the surface to be treated against vapor formation is hydrophobic in nature, for example certain anti-reflective lenses with a hydrophobic top coating, which makes applying a hydrophilic anti-vapor formulation to the surface in question problematic.

In a first aspect, the invention relates to an anti-vapor formulation for preventing vapor formation on a surface, wherein the anti-vapor formulation is a liquid based on an aqueous solution comprising a combination of 3-[hydroxy(polyethyleneoxy)propyl] heptamethyltrisiloxane and polydimethylsiloxane . Polysiloxanes are polymeric siloxanes with organic side chains; they are usually called silicones. The silicon-oxygen chain present in these silicones is similar to the silicon-oxygen compound in high-temperature resistant inorganic materials such as quartz, glass and sand. This molecular chain is very strong and resistant to attack by extreme temperature, oxidation, shear forces and chemicals. The most common polysiloxane is polydimethylsiloxane (PDMS), [Si(CH3)20]n, also known as dimethicone. 3- = [hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane is a Dimethylsiloxane/polyoxyethylene block copolymer. These silicones have no harmful effect on most materials, allowing the anti-vapor formulation to be safely applied to a wide range of materials. In addition, they are clear, colorless liquids. This is advantageous when they are intended to be applied to optical surfaces that transmit or reflect light. They are also not greasy, so the surface remains clean and therefore does not affect the visibility through the surface. PDMS and 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane have extremely interesting material properties such as hydrophobicity, low surface tension and high chemical and thermal stability.

An anti-vapor formulation based on these silicones also exhibits such interesting properties. For example, applying this formulation to a surface lowers the surface tension of that surface, This is an attractive property in the context of an anti-vapor formulation, Lowering the surface tension present on a surface to values significantly lower than those of water, the mutual attraction of the water particles will be greater than the attraction of these particles by the surface,

this makes the surface hydrophobic and will repel the condensation droplets formed. In this way vapor formation on the surface is prevented. PDMS and 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane are soluble in a wide range of solvents. In recent years, however, more and more people opt for an aqueous solution. The main reason for this evolution is directly related to environmental conservation. The use of water-based products makes it possible to limit the impact on environmental pollution and the greenhouse effect. In addition to their environmentally friendly properties, water-based products also have the following advantages: their storage, handling and transport are associated with greater safety, they are less harmful to the operator and they can be applied to a slightly moist substrate. concentration of 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane in the anti-vapor formulation less than 15% w/w, preferably less than 12% w/w, more preferably less than 10% w/w, even more preferably located between 5% and 10% w/w. In a preferred embodiment of the above anti-vapor formulation, polydimethylsiloxane has a concentration of between 1% and 5% w/w, preferably between 1% and 4% w/w, even more preferably between 2% and 3% w/w. An anti-vapor formulation having such a concentration and ratio of 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane and polydimethylsiloxane is capable of imparting to the anti-vapor formulation a sufficiently low surface tension such that, when applied to a surface, it will a hydrophobic coating and, as a result of this hydrophobic coating, a vapor barrier. Higher concentrations of 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiioxane and polydimethylsiloxane are unnecessary in terms of lowering the surface tension and only result in a higher production cost due to a larger amount of raw materials. In addition, higher concentrations of silicones contained in the anti-vapor formulation will have a greater impact on environmental pollution.

In a preferred embodiment, the anti-vapor formulation further comprises a solvent. In a preferred embodiment, the solvent has a concentration of between 1% and 5% w/w.

In a preferred embodiment, the solvent is an alcohol, such as butanol, ethanol, (iso)propanol or methanol.

Preferably the solvent is isopropanol.

Isopropanol evaporates quickly and will also dissolve oiliness and other impurities, providing the formulation with a cleaning effect in addition to its anti-vapor action.

In a preferred embodiment, the formulation is formulated in a spray, for atomizing the formulation onto a surface.

The anti-vapor formulation sees this in a container equipped with a nozzle for spraying.

A spray facilitates the distribution of the anti-fog formulation on the surface and is easy to use.

In one embodiment, the container is (partly) manufactured from a transparent material.

This makes it easy to check the residual volume in the container.

In a preferred embodiment, the nozzle is shielded by a removable cover.

This prevents accidental activation of the nozzle.

In a preferred embodiment, the spray pattern of the nozzle comprises a full cone shape. In one embodiment, the formulation, when sprayed onto a surface, forms a hydrophobic coating for a period of at least 16 hours, preferably for a period of at least 18 hours, further at preferably for a period of at least 20 hours. When the formulation is applied to the lenses of glasses, for example, the wearer will in most cases only have to do this once a day.

This increases the ease of use of the anti-vapor formulation.

In one embodiment, when sprayed onto a surface, the formulation forms a hydrophobic coating for a period of up to 48 hours, preferably for a period of up to 36 hours, preferably for a period of up to 28 hours.

A temporary coating has the advantage that it can be easily reapplied.

This is especially useful when the coating layer is damaged by extreme conditions.

Permanent coatings are very difficult to remove and reapply.

When these permanent coatings become damaged, they often cannot be repaired and it is necessary to replace the entire surface (eg a spectacle lens).

If a temporary coating is damaged, this coating can simply be replaced.

In a second aspect, the invention relates to the use of the aforementioned anti-vapor formulation to form a coating on a surface to prevent vapor formation on that surface.

The surface can take on any form and function. The surface can be, for example, the lenses of safety glasses, a face shield, a mirror or a lens.

The surface can be made of any material, such as plastic (e.g. thermoplastics such as polycarbonate), metal, stainless steel, glass, etc.

In a preferred embodiment, the surface is made of glass and the aforementioned anti-vapor formulation forms a coating on a glass surface, such as the glass plate of a watch, the screen of a smartphone, the lens of a camera, the lens of a microscope, etc. In a preferred embodiment, the aforementioned anti-vapor formulation forms a coating on the lenses of spectacles, in particular anti-reflective spectacle lenses.

Vapor formation on the glasses of glasses is frequent and is very annoying and possibly dangerous for the wearer of the glasses. Vapor formation often occurs under the influence of a temperature change, for example when changing from a colder to a warmer environment, such as when leaving a cold room or when entering a heated room when it is colder outside. Fog can also occur when the lenses come into contact with a source of warm air with a relatively high degree of humidity, such as during cooking or during an outdoor sport where there is excessive perspiration. Even when wearing a mouth mask, exhaled air with a relatively high humidity is sent upwards towards the glasses. The warm water vapor then condenses on the cold glasses. Due to the surface tension between the water molecules, small droplets are formed that refract the light, reducing the transparency of the glasses.

To protect against scratches and counteract reflections (anti-reflection), various layers are vaporized on the lenses during the production process of anti-reflective lenses. Reflections are suppressed by applying a number of - alternately different - layers with a thickness of approximately 100 nm. That thickness corresponds to a quarter wavelength of visible light, which is therefore extinguished as a result of interference.

A layer of quartz - SiO2 - is usually used for hard, scratch-resistant layers.

The number of layers on each side is sometimes ten, with a maximum of seven anti-reflection layers.

The top layer, the so-called topcoat, is usually a hard layer of SiO2 with a waxy layer that repels water, grease and dirt, This waxy layer gives the anti-reflective lenses a hydrophobic character, In a preferred embodiment, the molded coating is of the anti-fog formulation hydrophobic.

Due to the hydrophobic character of the coating, condensation droplets resulting from vapor formation will not be able to adhere to the treated surface.

In addition, the hydrophobic coating is suitable for application to a hydrophobic surface, such as anti-reflective lenses.

In a preferred embodiment, the aforementioned anti-vapor formulation forms a temporary coating.

In one embodiment, the coating is present for a minimum of 16 hours and a maximum of 48 hours.

In a preferred embodiment, the aforementioned anti-vapor formulation is atomized by means of a spray.

After atomizing the anti-vapor formulation it is necessary that the formulation is rubbed open with a cloth, preferably with a microfibre cloth. In a final aspect, the invention provides a kit comprising the aforementioned anti-vapor formulation, preferably provided in a container with nozzle, for atomizing the formulation, and a microfibre cloth.

The microfibre cloth allows an even spreading of the anti-fog formulation on the surface to be treated.

Unlike other textile forms, the microfibres will not absorb the anti-vapor formulation, so the formulation remains on the surface and forms an even coating on the surface.

In what follows, the invention is described by reference to: non-limiting examples illustrating the invention, and which are not intended or should be construed to limit the scope of the invention,

EXAMPLES EXAMPLE 1: An aqueous-based anti-vapor formulation of the present invention comprises 9% 3-[hydroxy(polyethyleneoxy)propyl] heptamethyltrisiloxane, 3% polydimethylsiloxane and 3% isopropanol.

The anti-fog formulation is contained in a kit together with a microfibre cloth and is used in this example to provide a coating to prevent vapor formation on anti-reflective lenses.

The anti-fog formulation is formulated into a spray, making it easy to spray onto a surface.

Hard particles such as sand are rinsed off the lenses and the anti-fog formulation is atomized onto the lenses.

After atomization on the glasses, the anti-fog formulation is spread evenly on the surface using the microfibre cloth.

Unlike other forms of textile, the microfibres will not absorb the anti-vapor formulation, so the formulation will not rub off, but will form an even coating on the surface.

Because of the propanol present in the formulation, the spectacle lenses are additionally cleaned by this operation.

The concentration and ratio of 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane (9%) and polydimethylsiloxane (3%) gives the anti-vapor formulation a sufficiently low surface tension that it is able to form a hydrophobic coating on the lenses.

This hydrophobic coating prevents the adhesion of condensation droplets and thus eliminates vapor deposits on the lenses.

In addition, the hydrophobic nature of the formulation allows it to be applied effectively to lenses of a hydrophobic nature, such as certain anti-reflective lenses.

Once applied, the hydrophobic coating remains on the glasses for at least 20 hours, so the wearer of the glasses should only treat them once a day to prevent vapor formation.

A second anti-vapor formulation according to the present invention with a different composition of 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane, polydimethylsiloxane and isopropanol was also tested and also gave good results.

EXAMPLE 2: The plastic lenses of goggles are treated with the anti-vapor formulation of the present invention.

The anti-vapor formulation is in a container with nozzle and this time contains 10% 3-[hydroxy(polyethyleneoxy)propyl] heptamethyltrisiloxane, 2% polydimethylsiloxane and 4% isopropanol.

After the misting of the anti-fog formulation on the lenses, this formulation is rubbed open with a microfibre cloth. The concentration and ratio of the components gives the anti-fog formulation a sufficiently low surface tension, which enables it to form a hydrophobic coating on the lenses.

This coating prevents fogging for a period of 20 hours.

Afterwards, the treatment with the anti-vapor formulation can be repeated.

A second anti-vapor formulation according to the present invention with a different composition of 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane, polydimethylsiloxane and isopropanol was also tested and also gave good results.

Claims (15)

CONCLUSIONS An anti-vapor formulation for preventing vapor formation on a surface, wherein the anti-vapor formulation is a liquid based on an aqueous solution comprising a combination of 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisiloxane and polydimethylsiloxane, wherein 3-[ hydroxy(polyethyleneoxy)propyl]heptamethyltrisioxane has a concentration below 15% w/w and polydimethylsiloxane has a concentration between 1% and 5% w/w. The anti-vapor formulation of claim 1, further comprising a solvent. The anti-vapor formulation according to claim 2, wherein the solvent has a concentration of between 1% and 5% w/w. The anti-vapor formulation according to any one of claims 2-3, wherein the solvent is an alcohol, preferably isopropanol, The anti-vapor formulation according to any one of claims 1-4, wherein 3-[hydroxy(polyethyleneoxy)propyl]heptamethyltrisioxane has a concentration of between 5% and 10% w/w. The anti-fog formulation according to any one of claims 1-5, wherein the formulation is formulated in a spray, before atomizing the formulation onto a surface. The anti-fog formulation according to any one of the preceding claims, wherein the formulation, when sprayed onto a surface, forms a hydrophobic coating for a period of at least 16 hours, The anti-fog formulation of claim 7, wherein the formulation when sprayed onto a surface forms a hydrophobic coating for a period of up to 48 hours. Use of the anti-fog formulation according to any one of the preceding claims, for forming a coating on a surface to prevent vapor formation on that surface, The use of the anti-fog formulation according to claim 9, wherein the surface is a glass surface. The use of the anti-vapor formulation according to any one of claims 9-10, wherein the coating is hydrophobic. The use of the anti-vapor formulation according to any one of claims 9-11, wherein the coating is temporary, and is present for a minimum of 16 hours and a maximum of 48 hours. The use of the anti-fog formulation according to any one of claims 9-12, wherein the surfaces are spectacle lenses. The use of the anti-vapor formulation according to any of the preceding claims 9-13, wherein the formulation is atomized by means of a spray. A kit comprising the anti-vapor formulation according to any one of claims 1-8 and a microfibre cloth,