JPS58213653A - Glass having low reflectance - Google Patents

Abstract

PURPOSE:A glass, having a low reflectance, prepared by forming a thin film consisting of a fluorosilicate compound of an amine containing a polyfluoroalkyl group on the glass surface, and capable of lasting the performance thereof for a long term. CONSTITUTION:A glass, having a low reflectance, prepared by forming a thin film of <=1mu thickness consisting of a fluorosilicate compound of an amine, containing a polyfluoroalkyl group (Rf), and expressed by formula I (Rf is 1-20C polyfluoroalkyl group which may contain an ether linkage; Q is bifunctional organic group; X, Y and Z are H or monofunctional organic group; a is an integer 1-3; b is 0 or an integer 1-3; c is an integer 1 or 2; d is an integer 4-6; e is 0 or an integer 1 or 2) on the surface thereof. The group Rf in formula I is preferably a group, containing the perfluoroalkyl group or ether linkage, and expressed by formula II and particularly a 4-12C perfluoroalkyl group, and m is an integer 2-10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a low reflectance glass in which the reflectivity of the glass surface is reduced. This relates to low reflectance glass formed in

Building window glass, vehicle window glass, glass doors, show windows, showcases, optical lenses, glass for optical equipment, eyeglass lenses, etc. may be exposed to glare or dazzle due to sunlight, reflections of lighting, or the surroundings. The landscape is causing problems with projection, visibility and transparency.

On the other hand, in recent years, the use of sunlight has been promoted due to energy conservation policies, and solar heat collectors with improved heat collection efficiency have been developed. There is a need to eliminate or reduce losses and allow large amounts of energy to pass through.

Conventionally, anti-reflection methods for glass surfaces have been developed for all Western-style parts, and vacuum evaporation or sputtering methods are used to form thin films of metal oxides, metal fluorides, metal nitrides, etc. on the glass surface for optical lenses. , glasses lenses,
It is put into practical use in filters, etc. Furthermore, a treatment agent and a treatment method have been proposed in which a coating film of the treatment agent is formed by applying, spraying, or dipping a low-reflection treatment agent made of a polymer substance on the glass surface. However, in the above method, The vacuum evaporation method or the sputtering method is limited to small precision optical parts due to the mechanism and cost of the equipment, and is not suitable for continuous manufacturing. Methods of forming low-reflection coatings by spraying, dipping, etc. have drawbacks in the durability or weather resistance of the treatment agents, such as the formed low-reflection coatings peeling off during glass cleaning operations. be.

Based on the recognition of the above-mentioned problems, the present inventor applied a thin film of a low-reflection treatment agent to the glass surface by a known method such as a spraying method or a dipping method without impairing the visibility and transparency of the glass. As a result of various research and consideration in order to provide low-reflectance glass that can be formed and maintain its performance for a long period of time,
Polyfluoroalkyl group-containing compounds (hereinafter abbreviated as Rff-containing compounds) have a small polarizability of fluorine atoms, and therefore a low refractive index. For example, the refractive index of C8F18 (25°C, the same hereinafter) is 1.271, (04F9) 3N is 1.290
, (CF, : CF2/C'F30CF=CF2) polymer is LaB5, low reflectance glass can be obtained by forming a thin film on the glass surface, and Rff
In order to firmly adhere the contained compound to the glass surface and maintain low reflectivity over a long period of time, 5iOH on the glass surface must be
-8i -0-R, -8i-Hal (H
Al is a halogen) is preferable, and the Rff-containing compound fluorosilicate is superior because it enables chemical adhesion to the glass surface. In particular, we have discovered that the hardness of thin films can be significantly improved.

Thus, the present invention has been completed based on the above findings, and involves forming a thin film of 1 μm or less on a glass surface, consisting of a fluorosilicate compound of an Rf-group shoulder-containing amine represented by the general formula %. The present invention provides a low reflectance glass characterized by the following characteristics.

In the above general formula, RfUf is a polyfluoroalkyl group having 1 to 20 prime numbers, preferably a perfluoroalkyl group having 4 to 12 carbon atoms, m is 2 to 10
Preferably, it is an integer of . Q is a divalent organic group,
Y and 2 are hydrogen atoms or -valent organic groups, al"l
: an integer of 1 to 3, b is O or an integer of 1 to 3, C is an integer of 1 or 2, d is an integer of 4 to 6, e is 0 or tI'il~2
is an integer.

The above-mentioned R4 group-containing amine can be obtained by various methods or routes; , No. 656, etc. For example, RfOH2CH2
RfCH2C12N(CH3)2 is synthesized by reacting f- and NH(CH3-) in a pyridine solvent, and R1-Coo CH3 is synthesized by reacting NH2(CH2)3N(
By reacting with C'H3)2 in an alcoholic solvent, υ
RfCONH(CH2)3N(CH3)2 is synthesized.

A fluorosilicate compound of an Rff-containing amine can be obtained by reacting such an Rff-containing amine with fluorosilicic acid. Acid aqueous solution 2o~10
It is carried out by dropping at a temperature of 0°C, and is carried out for 1 minute to 1 minute.
Completed in 0 hours.

Examples of the Rf group-containing amine fluorosilicate compound of the above general formula include (RfCH2CH2CH2,)2' SI Fa"θ
.

0 (RfCH2CH,N(CH3)2H): $, sa,
F62θ.

(Rfconu(CH2)3N(CH3)2H)226
), sIF,”'.

(RfSO2NH(CH2)3N(CH3)2H),”
SiF,”'.

(Rf C0NH(CH2)2NH2(CH2)35i
(OC2H5)3)2”■-84F,”θ.

咄(RfCH2CH2N(CH3)2H)21 (Si
F4 (OH)2 )2e+(RfCH2CH21J(
(:H3)2H)22■・(SiF, (OCOCH8
)2)20 are mentioned.

The thus obtained Rf group-containing amine fluorosilicate compound exhibits excellent effects as a low-reflection treatment agent for glass, and is also excellent as a water and oil repellent. These compounds can be used alone, but it is also possible to mix one or more of ethyl silicate, chlorosilane, silane coupling agents, etc. The form of use on the glass surface can be prepared in any form such as a solvent solution, solvent dispersion, emulsion, or aerosol according to a conventional method, but it may also be mixed with other Rf group-containing polymers, blenders, etc. Additionally, appropriate additives such as antistatic agents and crosslinking agents may be added.

The low-reflection treatment agent made of a fluorosilicate compound of an Rf group-containing amine is preferably prepared as a solution in a solvent containing 0.1 to 20% by weight based on the solvent.

The method for forming a thin film of such a solvent-based low-reflection treatment agent on the glass surface is the known spraying method.

Although a dipping method or the like may be adopted, the thickness of the thin film desired as a low reflectance glass is 1μ or less, preferably FiO, 1~
It is 0.5μ. The thickness of the thin film formed is determined by the processing conditions; for example, in the case of a dipping method, it is determined by the relationship between the processing agent concentration and the pulling speed.

After forming a thin film on the glass surface, a curing treatment is performed at a temperature of 100°C or higher for 20 minutes or more under 100% relative humidity to strengthen the adhesion of the thin film to the glass surface, making it suitable for use at low temperatures. A reflectance glass is obtained.

Reflectance fi of the low reflectance glass of the present invention in visible light
The reflectance is 0.5 to 0.7%, and an excellent fL effect is recognized compared to the reflectance of ordinary soda lime glass, which is 4.2%. Furthermore,
The hardness of the formed thin film is a pencil hardness of 3H to 4H, and R
A remarkable improvement is observed compared to 4B, which is a coating film containing only an f group-containing silane compound.

The use of the low reflectance glass of the present invention is not particularly limited, and various examples include, for example, window glass of buildings,
Vehicle window glass, glass.

Ah, show window, showcase 5. It can be used for glass for optical instruments, glass for sunlight condensing, etc.

The method for evaluating the low reflectance glass of the present invention is as follows. That is, the reflectance was determined by measuring the reflectance at a wavelength of 540 mμ at an incident angle of 5° using a self-recording spectrophotometer specular reflection light measurement accessory (manufactured by Hitachi, Model 323).
The thickness of the thin film is 1 step” (Rank Tail)
The hardness of the thin film was measured using a pencil scratch tester (
:rxs-5401)? The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 CnF2n+1CH2CH2N(CH3)2 (however, n
is 6.8°10,. 12, with an average value of 9.
0) 108.2F (0.2 mol), acetone 1,
002 was placed in a 500 ml three-neck flask equipped with a stirrer, stirred at 5°C, and then mixed with H2S1.002. F660%
Aqueous solution 482 (0.2 mol) was added dropwise, stirred for 5 hours,
Made it react. After the reaction was completed, a solvent solution was prepared by diluting reaction solution 1B with 68fffi acetone to make 100fO. Separately, a glass plate (soda-lime glass, r , 3 X
3 cm) 'f, prepared, immersed in a 2002 solution of the above preparation method in a 300 rttl beaker, pulled up at a pulling rate of 1Q, Qcrn/min, and then placed in 100% relative humidity. , and cured at 160°C for 1 hour. After the treatment, the thickness of the thin film formed on the glass surface was measured, and then the reflectance and hardness of the thin film were measured. The measurement results are shown in Table 1.

Examples 2 to 5 Solvent solutions were prepared in the same manner as in Example 1 except that the Rf group-containing compound in Example 1 was replaced with another Rf group-containing compound,
After a glass plate was treated in the same manner as in Example 1, the thickness (9) of the thin film, the reflectance (9), and the hardness (r) of the thin film were measured. The measurement results are shown in Part 2.

Comparative Example 1 CnF2n+I CH2CH2N(CH3) of Example 1
2 (where n is a mixture of 6.8.10.12 and has an average value of 9.0) It was diluted with 10ff acetone to give 1002, and after being treated on a glass plate in the same manner as in Example 1, the thickness of the thin film was determined. The reflectance and hardness of the thin film were measured.

The measurement results are shown in Table 1.

Comparative Example 2 A glass plate similar to that used in Example 1 was prepared, and its reflectance was measured. The measurement results are shown in Table 1.

Claims (2)

[Claims] (1) General formula ((RfQ)a Pxb Y<-a-b
'.・Wan-6・(Si Fa Ye) 2e (However,
In the above general formula, Rf is a polyfluoroalkyl group having 1 to 20 carbon atoms and may contain one or more ether bonds, Q is a divalent organic group, and X, Y and 2 are hydrogen atoms or -valent organic groups. is an organic group, a is an integer of 1 to 3, b is O or an integer of 1 to 3, C is an integer of 1 or 2, d is an integer of 4 to 6, e is 0 or an integer of 1 to 2 show. 1. A low reflectance glass characterized by forming a thin film of 1 μm or less made of a fluorosilicate compound of an Rf group-containing amine represented by the following formula on the glass surface. (2) The low reflectance glass according to claim 1, wherein Rf is a perfluoroalkyl group having 1 to 20 carbon atoms. is an integer of 1 or more]. The low reflectance glass according to claim 1.