KR20070011632A - Method of endowing antifog property on glass, plastic plates and optical lenses - Google Patents

Abstract

A method of endowing anti-fogging property to any of glass or plastic plate and optical lenses is provided to prevent fogging of the plate or lenses caused by difference in temperature and to increase transparency thereof by filling and fixing transparent quartz particles such as SiO2 or silica particles into pores of the surface of the plate or lenses through impregnation process. The method includes a step of penetrating and fixing pores on surface of a subject with transparent microfine particles which are made of SiO2 based silica or silicon quartz through impregnation. The subject is selected from glass plate, plastic plate and/or glass lenses. The transparent microfine particles are prepared by crushing transparent quartz into fine particles having a size of 10 nm or less and forming 12% suspension containing fine copper particles by adding the copper particles, 1% of surfactant, 1% of penetrating agent and 0.5% of bonding agent to washing water. The penetration process is conducted by vibrating the subject immersed in the suspension, circulating or agitating the suspension.

Description

Method of endowing antifog property on glass, plastic plates and optical lenses

When the temperature drops, we soon experience a frustrating phenomenon in which we can't see in front of the glass or spectacle lenses. There are also many people who have experienced watering when they try to use a mirror in the bathroom, because the mirror does not look steamy. An object of the present invention is to eliminate such inconvenience.

This misting phenomenon occurs when the surface temperature is lower than the dew point of the atmosphere when the surface of the solid transitions from a low temperature environment to a high temperature and high humidity environment, and water vapor condenses on the surface and turns into a large amount of droplets. If the contact angle is less than 30 °, more preferably less than 10 °, the condensate does not form individual water droplets even if water or steam in the air is condensed. Efforts to make it happen are ongoing.

I've been struggling to find a way to get rid of seaweed, and I've been reminded that glasses of crystal lenses are cool in summer and rarely frost in winter. The fine particles of SiO ₂ or transparent crystal particles of about a meter size are dispersed on the surface of glass plate, plastic plate, spectacle lens, etc. and penetrated into the pores, and are fixed by impregnation, coating, and gas permeation. The idea was to devise a way to prevent fogging.

Although glass plates, plastic plates, spectacle lenses, etc., are good products, there are many fine irregularities and pores of less than 1 μm in size on the surface thereof. Particularly, these fine pores are naturally formed or processed by the bonding structure between the elements of the composition. Inevitably occurs.

Even if the surface is hydrophilic, glass plates, plastic plates, eyeglass lenses, etc., as the seals pass, contaminants such as organic particles are adsorbed on the surface, making the hydrophilicity poor, and serves as a nucleus where water droplets condense.

In particular, contaminants adsorbed into the pores are more strongly adsorbed and difficult to remove due to the action of the pore walls and van der Waals attractive forces, thus degrading hydrophilicity once adsorbed.

However, when these fine pores are filled with finer sized transparent crystals or SiO ₂ particles and fixed in place so that they do not escape any more, the surface of the object increases by several times the hydrophilic surface area, thereby improving hydrophilicity, organic particles, etc. The contaminants of the adsorbed on the surface can be easily removed during use, and the particles fixed in the pores remain even after washing or wiping the surface of the object to maintain hydrophilic for a long time.

In addition, this method has the effect that the fine pores on the surface is filled with transparent quartz crystals or SiO ₂ particles to increase the clarity of glass, plastic, and spectacle lenses.

Currently used anti-fog methods can be classified into three types.

First, there is a method of applying a mixture of silica sol or titanium dioxide having good adhesion, transparency and hydrophilicity and applying it to an object. This includes UV coatings that utilize UV curing to further increase the strength. However, the strength of the film produced by this method is limited and does not exceed 3H. In addition, no matter how thin the coating, since the refractive index of the coating material is different, there is a problem that the effectiveness of the multi-treated to give a variety of visual effects disappears and the practicality is lost.

The second method is to treat the surface with plasma.

Modification of the surface of the object using plasma such as oxygen, hydrogen, nitrogen, helium, argon is obviously effective, but if any plasma is to increase the thickness or depth of treatment, the object is deteriorated, so it is extremely thin. As a result, the strength of the modified film is weak, and the effect of treatment is insignificant because the effect is lost even if it is rubbed once.

Third, there is a method of constructing an electric circuit with a conductive material on the film, and one example of using this method is to generate heat when electric wires are applied to a car window. This method has a disadvantage in that it is limited in use and costs for facility and maintenance. It will not be compared to simply allowing the glass to prevent fogging.

It is a task to devise a method to make use of both the excellent wear resistance and the antifogging effect for a long time, and the fact that the coatings treated for other purposes do not degrade their performance.

The present invention is a breakthrough method that is more concise, better performing, less trouble free, and less expensive to maintain than the currently used methods.

As an example of a treatment method consistent with the present invention,

First, the transparent crystal is crushed into fine particles having a size of about 10 nanometers or less.

Next, copper particles are used to make a suspension of about 12%.

The suspension can be made by adding 1% copper fine particles, 1% surfactant, 1% penetrant and 0.5% binder to the washing water. Due to the nature of the nanoparticles, it is not necessary to use a surfactant, but a surfactant and a penetrant may be used to promote the penetration of fine crystal particles into the pores.

Next, an object such as glass, plastic, lens, or the like is immersed in the suspension, and the object is vibrated, the solution is circulated, or stirred to infiltrate the transparent crystal microparticles into the pores. It is effective to vibrate the object lightly, such as moving up and down about once every two seconds, the impregnation time may vary depending on the size, thickness, etc. of the object, it is preferable that the impregnation period is about 7 days.

Next, the object is taken out of the impregnation liquid and dried and impregnated in a drying chamber in a state of blocking external contamination. Satisfactory results can be obtained by drying for about 3 hours in the range of 50 ° C to 300 ° C. In the process of drying, the transparent crystal fine particles that penetrate into the pores on the surface of glass, plastic, lens, etc. are bonded to each other to become large particles or to the pore walls to be fixed in the pores.

Finally, the surfactant and the like on the surface of the object are removed to obtain a finished product.

Depending on the shape of the object, it is also possible to promote the impregnation and reduce the impregnation time by several hours by using a reactor that keeps the interior in a low vacuum state in the range of 650 mmHg to 860 mmHg (1 atm).

Hydrophilic materials are not only SiO ₂ . TiO ₂ , BaTiO ₃ , TaTiO ₃ , LiNbO ₃ , KNbO ₃ , B ₁₂ GeO _{20 and} others, which are transparent and show hydrophilicity, but when many particles are aggregated and overlapped, the refractive index is severely distorted, transparent or hydrophilic Something wrong with

The present invention has a concise, high antifogging effect over a long period of time than the various methods currently used, and has the advantage of increasing the sharpness when the object requires transparency.

Claims (1)

Anti-fog to prevent long-term anti-fog by penetrating and fixing silica, silica, and especially transparent crystal fine particles of SiO ₂ composition in the pores existing on the surface of the object such as glass plate, plastic plate and spectacle lens Way