CS251646B1 - Method for producing non-glare reflective layers - Google Patents

Abstract

The essence of the method of producing non-glare reflective layers of rear-view mirrors for motor vehicles is that a layer of cobalt and its phosphides is first applied to the activated glass, and then a layer of nickel from a phosphite bath.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing non-dazzling reflective layers on top of organic or inorganic glass intended primarily for motor vehicle rear-view mirrors having a reflectance of more than 40% in the visible region of the spectrum without color distortion.

Motor vehicle rear-view mirrors increase traffic safety to a large extent. Perfect rear view without the risk of glare ensures reliable driving, but too low a mirror's reflection makes it difficult to observe the situation on the vehicle, especially at the time of day. For this reason, this reflectivity has been set at a minimum of 40%, but for reasons of possible glare, the 45 i limit should not be exceeded.

The prior art rear-view mirrors are produced on the basis of vacuum or cathodic sputtering of metal layers such as aluminum, nickel, impact and the like, and the layers thus produced can achieve virtually any reflectance. The disadvantage, however, is the lengthy and economically disadvantageous method of production, which consists in the relatively high financial costs incurred for the acquisition of vacuum apparatuses.

The production of reflective mirrors based on electroless chemical deposition of nickel from the hypophosphite bath is considerably less demanding, but the reflectance of the layers thus obtained does not generally reach the required 40%. It is also known to deposit amorphous cobalt layers and their phosphides. The layers thus formed meet the requirements for the desired reflectivity, but they have a reduced mechanical strength. As a result, after prolonged handling after application of the vacuum layer, it can easily be damaged, such as scratches and thus the spoiling of the mirror.

The deficiencies of the known reflective layers of the rear-view mirrors are largely eliminated by the object of the invention, which is a method of producing non-dazzling reflective layers on the surface of organic or inorganic glass intended primarily for motor vehicle rear-view mirrors. .

SUMMARY OF THE INVENTION An amorphous layer of coblat and its phosphides having a thickness of 0.15 to 0.50 µm and a nickel layer of hypophosphite baths having a thickness of 0.15 to 0.50 µm are first deposited on the surface of the pre-activated glass.

The main advantage of the reflective layers produced by the method according to the invention is first and foremost in that they have a reflectance in the visible range of 40 to 45%, while having a relatively high mechanical resistance.

This increased reflectivity is mainly due to the layer of cabbage and its phosphides, while the desired strength and mechanical resistance is favorably influenced by the nickel layer Ni of the hypophosphite baths. The production of these layers is relatively inexpensive without the need for complex manufacturing equipment, and complete deposition can be accomplished in 30 to 150 seconds.

Example

On the surface of a mirror glass previously mechanically polished and activated with a stannous chloride solution and sensitized with a palladium chloride solution, in an ammonium bath containing 1000 ml of HjO

3% cobalt chloride coci ₂ .ch ₂ o 3.5% sodium hypophosphite NaH ₂ PO ₂ .H ₂ O 2% sodium citrate ^Na 3 ^C 6 ^H 5 ° 7- ^2H 2 ° 5% ammonium chloride NH ₄ Cl

at 85 ° C, the reflective layer of cobalt and its phosphides formed in 30 seconds. Then the mirror was immersed in a 85 ° C bath containing 1% sodium hypophosphite 1% sodium citrate per 1000 ml H 10% nickel chloride 2% sodium citrate ₂

NaH ₂ PO ₂ .H ₂ 0 Na ₃ C ₆ H ₅ O ₇ .2H ₂ O

And after 60 seconds a nickel layer formed.

After applying the protective paint to one side of the mirror, the applied layer was removed from the other side with the polishing. This gave a mirror with a reflectance of 42% in the visible region of the spectrum.

The mirrors provided with the reflective layer of the invention are suitable for all kinds of motor vehicles, which are required to have mirrors.

SUBJECT OF THE INVENTION

Claims (1)

SUBJECT OF THE INVENTION Method for producing non-dazzling reflective layers on the surface of organic or inorganic glass, intended primarily for motor vehicle rear-view mirrors having a reflectance of more than 40% in the visible spectrum without color distortion, characterized in that an amorphous layer is applied to the pre-activated glass surface cobalt and its phosphides having a thickness of 0.15 to 0.50 and then a layer of Ni from a hypophosphite bath having a thickness of 0.15 to 0.50 µm.