JPS60264344A - Halide glass for infrared transmission - Google Patents

Abstract

PURPOSE:To provide a halide glass having excellent infrared transmittance and suitable for the transmission of infrared light, etc., by using cations of Pb, Cu and Cs as essential components and anions of Br and I as additive components. CONSTITUTION:Raw materials such as PbBr2, CuBr, CuI, etc. are weighed and mixed in a manner to form a lass composition containing 65-75% Pb<2+>, 5- 20% Cu<+>, 10-18% Cs<+>, 0-15% Ag<+> and 0-15% Cd<2+> as the glass-constituting anionic components, and containing 0-20% Cl<->, 70-90% Br<-> and 5-20% I<-> as glass-constituting anionic components. The mixture is molten by heating, and cooled to obtain the objective glass for the transmission of infrared light. The obtained glass has no absorption in a medium infrared region of 2.5-25mum wavelength, is producible in large quantities, free from deliquescence, and has relatively high glass transition point.

Description

DETAILED DESCRIPTION OF THE INVENTION a. Industrial Application The present invention relates to an infrared transmitting halide glass useful for transmitting infrared rays.

b. Prior Art The optical transmission bodies conventionally used are mainly made of quartz (Si).
It was an oxide glass mainly composed of n2).

However, this glass has a drawback in that it absorbs infrared light due to lattice vibration due to the strong bond between Si and O that forms the network, and can only transmit infrared light with a wavelength of up to 2 μm.

Therefore, various studies and reports have been made on materials that solve the above-mentioned drawbacks, that is, materials that have transparent windows in the infrared region with a wavelength of 2 μm or more. These materials are broadly classified into glass and crystalline materials, and among the glass materials is zirconium fluoride (ZrF4)! , non-fluoride halide glasses such as bismuth chloride (BiOJ3), or chalcogen glasses containing arsenic, selenium, tellurium, etc., and crystal materials such as thallium halide (TA'Br-
TA! I) Polycrystals such as Jl halide (AgOl-AgBr), potassium chloride (K(J), cesium bromide (
Single crystals such as OsBr) are known.

However, since heptafluoride glass has absorption based on lattice vibration, the transmission wavelength range of infrared rays is as narrow as about 1 μm. On the other hand, non-fluoride halide glass is considered to be the most promising candidate as an infrared transmitting material because it can well transmit infrared rays having a wavelength of 10 μm or more. However, currently reported glasses containing ZnOA2 or BiCl3 as main components lack practical use due to their significant deliquescent properties. Furthermore, chalcogen glass has many problems as an infrared transmitting glass because (1) it has infrared absorption due to lattice vibration in the mid-infrared region with a wavelength of gμm or more, and (2) it has infrared absorption due to structural defects in the glass.

On the other hand, among crystalline materials, polycrystalline materials have the disadvantage of large scattering at grain boundaries, and single crystalline materials have a growth rate of ~/min/min.
The disadvantage was that productivity was extremely low due to the small size of x cm.

I・□. □7. □, Yoyo7. □4 The present invention was made in order to eliminate the various drawbacks mentioned above, and the purpose is to obtain a glass that transmits infrared rays in the near-infrared to mid-infrared region extremely well and has excellent productivity. It is said that

d Means for Solving the Problems In order to solve the above problems, the present invention uses pb2+ Ou5~7S Ou+! as a cation component constituting the glass. ;-20 C6" 10~/zaAg+ 0~15 and CCO~, 2 as an anion component constituting the glass
0 Br"" 70~q.

Provide glass.

In the above glass composition, pb, Cu, and C8 components are essential components of the present invention, and the Pb component is a component that forms a glass network together with anions. Qu and Os are components that modify the network structure and have the effect of promoting glass formation. Ag and CD are additional components that both increase the stability of the glass against crystallization.

All of the above halide compounds as cationic components have wavelengths of 2. ! ; It has no absorption in the mid-infrared region from l1m to 25 μm, and has no deliquescent property. The content of Pb is tS~7j mol% as a ratio of cationic components (ion ratio), and if the amount is less than the lower limit or more than the upper limit, the crystallization rate becomes faster and it is difficult to obtain a stable glass body. Further, the content of O is 5 to 20 mol %, and if the content is less than the lower limit, the crystallization rate will increase and it will be difficult to obtain a stable glass body. Furthermore, the glass transition point of this type of glass is mainly determined by the amount of Gu, and if the amount is more than the upper limit, the glass transition point will be below SO''C, which is impractical.Cs is 10~/,
The amount is 1' mol %, preferably 70 to 70 mol %, and if the amount is less than the lower limit or more than the upper limit, the crystallization rate will increase and it will be difficult to obtain a stable glass body.

The preferable concentration range of the additional components Ag and 0(i) is 0 to 75 mol%, and the more preferable range is Ag.

(j) Both Cd is 0 to 3 mol%. If the amount of both is greater than the upper limit, the crystallization rate will increase and it will be difficult to obtain a stable glass body.

The preferable range of the anions chlorine (Of), bromine (Br-), and iodine (I-) ions is 0 to 20° and 70 to 70°, respectively, in terms of mol% (ion ratio) of the anion component.
and 5-20%. If the amount is less than these lower limits or more than these upper limits, the crystallization rate will increase and it will be difficult to obtain a stable glass body.

eExample Example/Pb Br2. Ou Br, Cu I, Os I reagents Pb13r2≦, 3-% Le%, CuBr 10.
,! ! r%ru%, OuI 9.7. ! tmol%, C
8I/! 3 g of mixed powder prepared at a ratio of i mol % was placed in a Pyrex test tube with a diameter of 10 mm and a length of gs mm, and heated in a vacuum dryer at /20"C for 77 hours. Thereafter, nitrogen gas was added at a volume ratio of 9 The glass sample was melted at qoo''C%/hour in a mixed gas atmosphere of chlorine gas S% and chlorine gas S%, and the melt was poured into a brass mold to produce a glass sample with a thickness of 0.3 mm. In order to examine the presence or absence of crystals (A), evaluation was performed using a polarizing microscope and X-ray diffraction, but the presence of crystals was not confirmed. Further, the glass transition point was measured by differential thermal analysis and was found to be Tg=3/''C. The X-ray diffraction pattern of the glass is shown in FIG. 1, and the measurement results of the infrared transmission characteristics are shown in FIG.

In Figure 1, the X-ray diffraction peak peculiar to crystals is not observed, indicating that the sample is amorphous.
A slight absorption peak thought to be caused by water at m and 3 μm, and a slight absorption peak thought to be caused by oxides from around 11 μm are observed. However, these absorptions are due to external factors and are not considered to be an essential problem of the material. That is, from FIG. 2, the glass of this example is 2.3 μm-! It can be seen that light with a wavelength of 0 μm is transmitted satisfactorily.

71.1・　″″I′. ′〜′.

Pt prepared to have the composition ratio shown in Table 1)
Br2, 0uBr, CuI, C3I, AgBr, 0dB
3 g of mixed powder such as R2 was melted in the same manner as in Example 7, and the melt was poured into a brass mold to prepare a glass sample with a thickness of 0.03 mm. These glass samples were examined for the presence of crystals using a polarizing microscope and X-ray diffraction.

Table 1 shows the observation results of the stability of the glasses. No crystals were observed in any of the glasses obtained in Examples 2 to 10.

The infrared transmission characteristics of the obtained glass were also measured, and as in Example 1, it successfully transmitted light with a wavelength of λ, S μm-20 μm. Table 7 also shows the measured values of the glass transition point (Tg) of the obtained glasses.

Comparative example/~g pt prepared to have the composition ratio shown in Table 2)
Br2, 0uBr + CuI, OsI, A
3 g of mixed powder such as g% I3r l CdBr2 was melted and a sample was prepared in the same manner as in Example 1, and the same evaluations as in Examples λ to IO were performed.

No crystals were found in the glass sample of Comparative Example 1 when evaluated using a polarizing microscope and X-ray diffraction.

However, the glass transition point was Tg-4'4°C, which was lower than that of the Examples. Furthermore, in all of Comparative Examples 2 to g, the presence of crystals was confirmed using a polarizing microscope. Here, the * mark in the table indicates a component that deviates from the composition range of the present invention.

f Effects of the Invention Table 2 The glass according to the present invention is composed of essential components of pb, Qu, Qs, bromine and iodine, and additional components of Ag1Od and chlorine.

The glass obtained from these components has a wavelength of 2.3 μm-
2! ; It has no absorption due to internal factors in the mid-infrared region of μm. In addition, the glass of the present invention is extremely suitable for mass production, and furthermore, the glass of the present invention is not deliquescent and has a relatively high glass transition point (Tg≧SO″C), so it can be used as an ultra-low-loss optical communication fiber, an infrared fiber, etc. O can be applied to humidity measurement fibers, etc.

[Brief explanation of the drawing]

FIG. 1 is an X-ray diffraction pattern of the glass in Example/2.
The figure is an infrared transmission characteristic diagram of the glass of Example/. ■ '# Island 2α (e) Figure 1 Wavelength (, um) Figure 2 (/l) Procedure Correction Book Showa! ;G month 2, 1999/Special application for display of incident 1972-/203! No. 9 - Name of the invention Halide glass for infrared transmission 3 Relationship with the case of the person making the amendment Patent applicant address 4-8 Doshomachi, Higashi-ku, Osaka-shi, Osaka Name Name
(<toθ) Shin Saiga, Representative of Nippon Sheet Glass Co., Ltd.
Og Agent 7 Contents of amendment (1) In the Ag ion component column of Example 3 in Table 1 on page 1 of the specification, ``12'' has been changed to l'-/,! Correct to J. (2) Specification page I Table 7 Example No. 1 Ionic component @
Vc[/! ;J,! Niall (1) ti: [! ;J
K correction t, B. (3) "1X-ray diffraction pattern" on page 13 of the specification should be corrected to "X-ray diffraction pattern." (2)

Claims (1)

[Claims] (1) Pb as a cationic component constituting glass
J j~7j cu+s~20 O8+lO~/lr Ag+O~/j As an ionic component, ai-o~20 13r-70~90 Ras.