JP3135944B2 - Low reflection transparent body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to paintings, showcases,
The present invention relates to a low-reflection transparent body obtained by applying an antireflection technique to a transparent plate used for a window or the like.

[0002]

2. Description of the Related Art An antireflection film having a high light transmittance is produced by various methods, but it is roughly based on the formation of a multilayer film and a heterogeneous film. Multilayer films are often used for lenses,
The purpose is to reduce reflected light due to optical interference. In general, a heterogeneous film or structure in which the refractive index continuously changes in the thickness direction of the film is obtained by, for example, etching the glass surface with a chemical and forming a fine uneven surface. .

[0003]

However, the method of applying the optical interference effect is a film forming method obtained by a vacuum evaporation method, and a very large film forming method is required for a large material such as a painting, a showcase, and a building material. Since an apparatus is required, it is impossible to keep the accuracy of the film thickness uniform over the entire surface.

On the other hand, a method of providing an inhomogeneous film or structure on the surface of a transparent body involves etching a glass plate with a chemical. However, it is difficult to obtain fine unevenness, and such an inhomogeneous film is viewed obliquely. It is whitish and unsuitable for painting.

The problem to be solved is to provide an antireflection effect to a relatively large transparent plate for paintings, showcases, building materials, etc., unlike the high mechanical accuracy required for optical and electronic equipment. An object of the present invention is to provide a low-reflection transparent body that is less uncomfortable than a visual point.

[0006]

The transparent body of the present invention has a light transmittance of about 90%, but has a particle diameter of 0.3 μm to 0.01 μm in order to effectively perform irregular reflection on the surface.
A semi-buried structure in which μm of SiO ₂ fine particles are spread is made using a resin coating agent on the surface of the transparent body, and a fine uneven surface is made on the surface in contact with the air. Is formed, and the surface of the adhered SiO ₂ fine particles has a particle size of 0.1 μm or less.
_A low-reflection transparent body is covered with a resin layer containing _two fine particles. Also, instead of the resin layer containing MgF ₂ fine particles,
Forming a transparent resin layer that is amorphous with perfluoro
You may.

[0007]

Embodiment 1 FIG. 1 is a schematic sectional view of a low antireflection film of the present invention. Acrylic resin plate 1 (1m ×
2 mx 2 mm). A normal dry type acrylic resin coating agent (clear) 3 is diluted with a solvent so as to have a solid content of 30%, and SiO ₂ fine particles 2 having a particle size distribution between 0.3 μm and 0.01 μm are uniformly dispersed therein. 1.2% by weight, including a spacer for achieving good dispersion, was sufficiently sealed and stirred. A coating agent of 15 seconds was obtained with C3. This coating agent was injected into the nip between the pre-doctor of the transfer roll coater and the steel doctor, and was applied to one side of the acrylic resin plate at a rate of 0.6 g / m ² at a peripheral speed of the backup roll of 10 m / min. After a setting time of 2 minutes, drying was performed for 5 minutes by IR drying. Then, the coating was dried on the opposite surface in the same manner. The finished board was framed appropriately and hung on the wall in the room, and the picture could be confirmed at the position where the shadow of the window reflected.

[0008]

Embodiment 2 FIG. 2 shows a case where a PET film is used for a transparent body.
It is a side sectional view showing a process in the case. Tran as a painting machine
Since a spur roll coater is used, explanation of each roll
do. 4 is rubber pre-doctor roll, 5 is steel
6 is a rubber transfer roll, 7 is a roll
Teal transfer roll, 8 is rubber backup roll
, 9 is a film roll, 10-1, 10-2, 10
-3 is a transport roll. Each roll rotates in the direction of the arrow
Yes, but with a slight difference in peripheral speed
I started to ring to prevent split patterns
I have. Spacer on two-component urethane resin as coating agent 11
SiO dispersed in_TwoParticle size of 0.3 μm to 0.01 μm
1.2 wt% of fine particles having a particle size distribution and a viscosity of 1
Adjust to 00 cps, rubber pre-doctor roll 4 and stainless steel
Into the nip of the doctor roll 5. Rubber bag
0.4 g /
m ^TwoThe coating agent 11 is transferred as a thin film at the ratio of
10-1 and 10-2 and 10-3. Dry
Was dried with a far infrared heater for 4 minutes.

The dried film 13 is once wound on a roll, and the viscosity of the two-component urethane resin containing no SiO ₂ is adjusted again to 150 cps by monomer dilution, and the transparent plate is completely acrylic to completely cut off ultraviolet rays up to 380 nm. A resin plate was selected, applied to the wet plate with a reverse coater so as to have a wet film thickness of 2 μm, and then pressed and bonded while degassing the film with a laminator machine. Such a bonding was performed on both surfaces of the resin plate to obtain a transparent plate which has an antireflection function and cuts ultraviolet rays.

[0010]

Embodiment 3 As shown in FIG.
A coating agent 14 is applied to the low-reflection transparent plate to which the fine particles of iO ₂ are fixed.
As a result, 1.2 wt% of fine particles 15 having a particle size distribution of MgF ₂ of 0.05 μm were added to a photopolymerizable urethane acrylate with a spacer interposed therebetween to uniformly disperse the particles, and the viscosity was adjusted to 50 cps. It is applied to the upper layer of the low reflection transparent plate 16 at a rate of 0.3 gr / m ² with a coater and applied with an ultraviolet lamp having an output of 80 w / cm.
Irradiated for 2 seconds to cure. The setting time was 10 seconds. Thus, a structure was formed in which the protective film of SiO ₂ (refractive index: 1.46) was further covered with MgF ₂ (refractive index: 1.38), which is a low-refractive substance.

[0011]

Example 4 A transparent fluororesin (a trade name, Cytochrome) which is perfluoro and amorphous was added to the coating agent shown in Example 1.
, Manufactured by Asahi Glass Co., Ltd.) and diluted with a perfluoro-based solvent to adjust the viscosity to 100 cps.
After adding SiO ₂ fine particles of 3 to 0.01 μm in a ratio of 1.2 wt% including a spacer and sufficiently stirring the mixture, 0.6 g of the acrylic resin plate was applied to an acrylic resin plate using a gravure offset printing machine.
r / m ² was applied. The plate was dried at a plate surface temperature of about 60 ° C. for 10 minutes using a far-infrared dryer. FIG. 1 is a schematic cross-sectional view of the structure thus obtained. The refractive index of the fluororesin used in this example is as low as 1.34, and the refractive index on the surface in contact with air is very small. The average refractive index closer to 1 is obtained in combination with the uneven surface.

[0012]

Embodiment 5 A transparent fluororesin (trade name, CYTOP, manufactured by Asahi Glass Co., Ltd.) is used instead of the solution comprising the photopolymerizable urethane acrylate and the fine particles of MgF ₂ shown in Example 3.
Is used. Fine particles are not added to the fluororesin used at this time, and a protective film having a refractive index (n = 1.34) is simply provided.
/ M ² , a thin film having a thickness of 0.1 to 0.2 μm is formed in an uneven shape.

[0013]

The low-reflection transparent body obtained from the present invention has M
It has a function of continuously changing from a low refractive index to a high refractive index from a surface in contact with air to a transparent body using a fine particle such as gF ₂ or SiO ₂ and a function of scattering surface reflected light. Therefore, a transparent body with less light interference color can be obtained as compared with other antireflection films formed by vacuum evaporation. For viewing paintings, since the shadow of the observer is not reflected and strong reflected light from the lighting window can be prevented, a calm atmosphere can be produced at exhibitions and the like. Further, the thin film containing MgF ₂ has the effect of reducing the average refractive index of the resin to be fixed by the thin film,
It is useful for preventing the adhesion of unpleasant stripes such as scales. Although urethane acrylate is used in the present invention, a protective film having high water repellency can be obtained by disposing a thin film of an organic fluorine compound or an organic silane compound on the upper layer. In addition, the low-reflection film as the low-reflection transparent body of the present invention can be watched without obstructing the night view by being stuck to the indoor side of the window glass of a high-rise building.

[Brief description of the drawings]

FIG. 1 is an enlarged schematic view showing a low-reflection transparent body in which a low-reflection film is formed on the surface of a transparent resin plate.

FIG. 2 is a side view showing a step of forming a thin film on a film using a transfer roll coater.

FIG. 3 is a schematic cross-sectional view showing a low-reflection transparent body in which the surface of fine particles of SiO ₂ is covered with a resin layer containing MgF ₂ .

[Explanation of symbols]

1 transparent resin plate 2 SiO ₂ fine particles 3 coating agent 4 rubber pre doctor 5 steel doctor 6 rubber transfer roll 7 steel transfer roll 8 rubber backup roll 9 film roll 10 carrying roll 11 coating agent 12 film 13 low-reflection film 14 coating Agent 15 MgF ₂ fine particles 16 low reflection transparent body

Claims (3)

(57) [Claims] 1. A resin coating material having a refractive index equal to or less than that of a main resin constituting the resin plate or film on the surface of the transparent resin plate or film, and having a particle diameter of 0.3 μm to 0.1 μm. A thin film layer is formed so as to bury semi-buried 01 μm SiO ₂ fine particles, and the resin coating is cured to fix the fine particles. Continuously, from the surface in contact with air to the main body of the resin plate or film. A low-reflection transparent body in which a portion where the average refractive index changes is formed and the surface of the fixed SiO ₂ fine particles is covered with a resin layer containing MgF ₂ fine particles having a particle size of 0.1 μm or less. 2. The surface of a transparent resin plate or film
The main resin constituting the resin plate or film,
Using a resin coating agent having the same or lower refractive index
Semi-embedded SiO ₂ fine particles of 0.3 μm to 0.01 μm particle size
Form a thin film layer so as to submerge and cure the resin coating agent
And fix the fine particles, and make the resin
The average bending of the sheet or film is continuously
Form a moiety folding rate changes, the low-reflection transparent body covering the surface of the SiO ₂ fine particles was subjected to solid-wearing transparent resin is amorphous perfluoro. 3. A low reflection transparent plate obtained by sticking the low reflection transparent body according to claim 1 or 2.