JPH0432019B2 - - Google Patents

Description

[Detailed description of the invention]

[Object of the Invention] (Industrial Application Field) The present invention relates to an ultraviolet-transmissive heat-absorbing glass that transmits ultraviolet rays of 356 nm, absorbs visible light and infrared rays, and has excellent heat resistance. (Conventional technology) Conventionally, in order to cure ultraviolet curable resin, etc.
This is done by irradiating ultraviolet light with a mercury lamp, but
Approximately 55% of the energy emitted from the light source becomes infrared rays and visible light, and approximately 30% becomes heat, etc., so this energy is directly absorbed by the irradiated object or device, and secondarily causes damage to the irradiated object. Increase temperature. In recent years, the application of ultraviolet rays in connection with electronic components and materials has been remarkable, but many synthetic resin films and molded products such as polyester, and circuit components such as ICs are sensitive to heat, so it is difficult to irradiate them at low temperatures. There is a need for an ultraviolet irradiation device that can do this. For this purpose, in practical terms, the envelope tube of the mercury lamp is formed of a double tube body consisting of an inner tube made of quartz, and pure water is introduced into the gap between the inner tube and the outer tube, and heat rays (infrared rays) are introduced. ) is being absorbed. but,
This water cooling method requires large and complicated equipment, so
Recently, a convenient method has been adopted that blocks infrared rays and radiant heat by interposing a heat-resistant glass filter between the mercury lamp and the irradiated object, which transmits 356 nm ultraviolet rays, which are effective for resin curing, and absorbs heat rays. has been done. (Problem to be Solved by the Invention) However, a glass filter made of ordinary silicate glass that transmits 356 nm ultraviolet rays and absorbs visible light and infrared rays has a transition temperature of about 500°C.
Since the heat resistance is low and the heat resistance is slightly inferior, if the device is miniaturized by using a high-pressure mercury lamp, there is a drawback that it will be damaged by the heat. The present invention was made in consideration of the above circumstances, and
The purpose of the present invention is to provide an ultraviolet-transmitting and heat-absorbing glass that transmits 356 nm ultraviolet rays, absorbs visible light and infrared rays, and has excellent heat resistance. [Structure of the Invention] (Means and Effects for Solving the Problem) In order to achieve the above object, the present invention increases the transition temperature of conventional filter glass to 580°C or higher without impairing its optical properties. Therefore, the heat resistance is improved. i.e. in weight percentage
_Sio2 48~55%, _{Al2O3 4} ~12%, _{B2O3 4} ~13%,
Na ₂ O2 ~ 6%, K ₂ O 0 ~ 5%, Li ₂ O 0 ~ 1%,
Na ₂ O + K ₂ O + Li ₂ O3 ~ 7%, BaO25 ~ 33%,
CaO0~8%, MgO0~8%, ZnO0~8%,
PbO0~5%, BaO+CaO+MgO+ZnO+PbO25
~35%, NiO0.5%, CoO0.2~2%, As ₂ O ₃ 0~1
%, Sb ₂ O ₃ 0-1%, As ₂ O ₃ +Sb ₂ O ₃ 0.3-1.5%, and has a transition temperature of 580° C. or higher. Next, the reason why the components of the glass of the present invention are limited to the above range will be explained. SiO ₂ is the main component forming glass, but 55
If it exceeds 48%, the meltability of the glass will deteriorate, and if it is less than 48%, the transition temperature will decrease. When Al ₂ O ₃ exceeds 12%, the meltability becomes poor and striae and unfused substances are likely to occur in the glass, and when it is less than 4%, the transition temperature and chemical durability decrease. When B ₂ O ₃ exceeds 13%, the transition temperature decreases and chemical durability deteriorates, and when it is less than 4%, meltability deteriorates. Na ₂ O, K ₂ O, and Li ₂ O are effective in improving meltability, but if the upper limit of each is exceeded, chemical durability decreases, and if the total amount is less than 3%, the viscosity of the glass increases. increases and the meltability deteriorates. BaO is 33%
If it exceeds 25%, the meltability will deteriorate, and if it is less than 25%, the transition temperature will decrease. BaO, CaO, MgO,
If the total amount of one or more of ZnO and PbO added exceeds 35%, chemical durability will decrease, and 25%
If the amount is less, the meltability will deteriorate. NiO and CoO are used together to absorb visible light and infrared rays, but when the upper limit of both is exceeded, the transmittance of 356 nm decreases, and when it is less than the lower limit, the transmittance of visible light and infrared rays increases, and heat rays No absorption effect. When the total amount of As ₂ O ₃ and Sb ₂ O ₃ exceeds 1.5%, the clarification effect is not promoted and bubbles are generated, and when it is less than 0.3%, no clarification effect can be expected. Additionally, the transition temperature of this glass was limited to 280°C or higher in order to obtain the required heat resistance. (Example) Examples of the present invention are shown in the following table. Inside the table, glass set

【table】

[Table] The composition is shown in weight percentage, and the heat resistance is shown in the breakage rate when the glass temperature is rapidly raised from room temperature to 400°C in 2 minutes. No. 4 glass has a BaO content of 25
% and the transition temperature did not reach 580℃,
No. 5 glass is a comparative example of silicate glass. The spectral transmittance characteristics of the glass of the present invention are shown in the figure. In the figure, A is the characteristic curve of Example No. 2 glass, and B is the characteristic curve of Comparative Example No. 5 glass. From the table and the spectral transmittance characteristic diagram, it is recognized that the glass of the present invention has a transmittance of 356 nm ultraviolet rays and infrared rays that is almost the same as that of conventional silicate glass, but has significantly superior heat resistance. It will be done. [Effects of the Invention] As described above, the present invention is a barium borosilicate glass that transmits 356 nm ultraviolet rays and absorbs visible light and infrared rays, and has a transition temperature of 580°C or higher. Since it has superior heat resistance compared to silicate glass, it has the advantage that it can be applied to glass filters, etc. of ultraviolet ray irradiation equipment for resin curing, and the equipment can be made smaller.

[Brief explanation of drawings]

The drawing is a curve diagram showing the spectral transmittance characteristics of the glass of the present invention and the conventional glass. A: Invention glass (Example No. 2), B: Conventional glass (Comparative Example No. 5).

Claims (1)

[Claims] 1 SiO ₂ 48-55%, Al ₂ O ₃ 4-12% by weight percentage,
_B2O3 4~13%, _Na2O2 ~6%, _{K2O0 ~} 5%,
Li ₂ O 0 ~ 1%, Na ₂ O + K ₂ O + Li ₂ O 3 ~ 7%,
BaO25~33%, CaO0~8%, MgO0~8%,
ZnO0~8%, PbO0~5%, BaO+CaO+MgO
+ZnO+PbO25~35%, NiO0.5~5%, CoO0.2
~2%, _{As2O3 0 ~} 1%, _{Sb2O3 0} ~1%, _As2O3
+ Ultraviolet transmitting and heat ray absorbing glass containing 0.3 to 1.5% of Sb ₂ O ₃ and having a transition temperature of 580°C or higher.