JPS62128946A - Tellurite glass - Google Patents

Abstract

PURPOSE:To produce the titled high-refractive index tellurite glass with less coloration and wear and having good workability by incorporating TeO2, P2O5, PbO, Li2O, ZnO, and other oxides into the glass. CONSTITUTION:The tellurite glass composed, by mol, of 10-85% TeO2, 1-50% P2O5, 1-50% PbO, 0-30% Li2O, 0-40% ZnO, where the total amt. of Li2O and ZnO is regulated to 1-40%, 0-30% Na2O, 0-30% K2O, 0-25% Rb2O, 0-20% Cs2O, where the total amt. of Na2O, K2O, Rb2O, and Cs2O is controlled to 0-30%, 0-20% MgO, 0-20% CaO, 0-20% SrO, 0-35% BaO, where the total amt. of MgO, CaO, SrO, and BaO is adjusted to 0-35%, 0-5% Ta2O5, 0-20% Nb2O5, where the total amt. of Ta2O5 and Nb2O5 is regulated to 0-20%, 0-15% SiO2, 0-25% GeO2, 0-30% B2O3, 0-10% Al2O3, 0-20% Sb2O3, 0-15% In2O3, 0-4% La2O3, 0-4% Y2O3, 0-4% Gd2O3, 0-4% Yb2O3, 0-4% ZrO2, 0-10% Bi2O3, 0-20% TiO2, and 0-7% WO3 is prepared.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to Chillai 1 glass, and in particular, to glass with abrasion resistance,
Tellurite glass is highly durable, has little coloring, and has a high refractive index, and is used for optical glasses.

However, it is well known that a glass with a high refractive index can be obtained by using TeO2 as a glass-forming oxide, and Japanese Patent Publication No. 48-9083 (hereinafter referred to as "Prior Art Example 1") describes TeO2-wo3. - The Li20 series was further developed in 1977.
-17571 (hereinafter referred to as "Conventional Example 2").

), the TeO2-P2 05 -WO3 system was
-28454 (hereinafter referred to as “Conventional Example 3”))
e02-ZnO-Na20 and Li20 systems have been proposed, respectively. In conventional example 1, TeO2, WO3, L
It is said that the devitrification property was improved with Li20 in the base component consisting of i20, and the water resistance was improved by adding a fourth component to the base component, but this is still not satisfactory. In conventional example 2, P2O is used as the basic component.
Although it is said that the water resistance was improved and a chemically stable glass was obtained in Example 5, it is still not satisfactory as in Conventional Example 1. In conventional example 3, TeO2, ZnO, Na
It was developed as a glass for acousto-optic devices using 20.1-i20 as a basic component, and it is said that it was possible to obtain a glass with excellent chemical durability and stability at 2nO. The durability is not sufficient, for example, it is low compared to other optical glasses, and there is also the problem that the glass is soft because the glass forming oxide is only TeO2. Furthermore, in Conventional Example 1 and Conventional Example 2, since -03 is contained in an amount of 20 to 30% and 8 to 22 mol%, respectively, a considerably strong yellow coloring is observed in the glass. On the other hand, the abrasion characteristics of glass have not yet been resolved in Conventional Example 1, Conventional Example 2, and Conventional Example 3, and all of them have low abrasion resistance, are difficult to process, and are easily scratched when handled. There was a problem.

[Problem to be Solved by the Invention 1] The present invention has been made in order to eliminate the problems of the prior art as described above, and the first purpose is to reduce the coloring of the glass and to reduce the wear and tear. The purpose of the present invention is to provide a high refractive index tellurite glass that has a high refractive index and has good workability.A second object is to provide a tellurite glass that has excellent durability and devitrification resistance.

[Means for Solving the Problems] As a result of extensive research in order to achieve the above object, the present inventor has developed a glass-forming oxide with 1q p2 o.
5. The PbO component reduces coloring and hardens the glass while expanding the vitrification area, and the PbO component increases the refractive index of the glass and increases the stability of the glass.
By further adding 2nO and Li20 components, p
It has been found that in coexistence with an optimal amount of 2 o5, a glass with extremely excellent durability and excellent devitrification resistance can be obtained. As a result, it was found that a stable and relatively hard tellurite glass could be obtained without adding the three components that exhibit strong coloration.

Therefore, in order to obtain a high refractive index glass, we found a glass based on the TeO2 component and containing P2 05 , PbO, ZnO, and Li20 as essential components in appropriate amounts.
The present invention has now been completed.

The tellurite glass according to the invention, in mol %,
is 10-85, P2O5 is 1-50, preferably 1-50.
40), PbO is 1 to 50, L120 is 0 to 30, Zn
O is 0-40, L120 and ZnO metals are 1-40, N
a20 is 0-30, K2O is 0-30, Itb2o is 0-25, CsO is 0-20, Na20, K2O and l1
Total amount of b2 o and CsO is 0 to 30, HgO is 0 to 20
．． CaO is 0-20, SrO is 0-20, BaO is 0
~35, the total m of MgO, CaO, sro, and BaO is 0~
35, Ta205 is 0-5, Nb2O5 is 0-20, T
a2O5 and Nb2. Total amount of 05 is 0 to 20, Si 0
2 is 0 to 15, Ge 02 is 0 to 25, B2O3 is 0 to
30, A1203 is 0-10, sb2 o3 is 0-20
．． In203 is 0 to 15, t-a2 o3 is 0 to 4,
Y2O3 is 0-4, Gd203 is 0-4, Yb2O3 is 0-4, Zr02 is 0-4.8i203 is 0-10,
Ti02 is 0-20 (preferably 0-10), WO3
It is characterized by containing 0 to 7, respectively.

Next, the reasons for limiting the constituent components of the present invention will be described. T
eO2 becomes a glass-forming oxide and is essential as a component that increases the refractive index, but if it exceeds 85%, the glass becomes unstable in terms of devitrification resistance, and if it is less than 10%, Ge 0
2. Even if PbO or the like is contained, it is difficult to obtain a high refractive index in terms of resistance to devitrification. Furthermore, when -03 and Ti02 are contained, coloring increases even though a high refractive index is obtained.

Like TeO2, P2O5 becomes a glass-forming oxide and is essential for increasing the hardness of the glass, increasing the devitrification resistance, and making the glass stable. If it exceeds 40%), the refractive index will decrease and the water resistance will also deteriorate. PbO increases the refractive index of glass, stabilizes the glass, and improves water resistance, but if it is less than 1%, the effect is small, and if it exceeds 50%, it makes the glass unstable. 2nO and [120 are essential for stabilizing glass and improving water resistance, but if their total content is less than 1%, their effect will be small, and if it exceeds 40% and 30%, respectively, it will cause refraction. At the same time, the water resistance decreases. Other components are not essential components and are added as appropriate for the purpose of adjusting optical constants such as refractive index and dispersion rate, improving devitrification resistance, improving meltability, and improving chemical durability. Na20, K20, Rb20
, CsO, and HgO, CaO, SrO, BaO are
If added in excess, the refractive index will decrease, the hardness will become too small, and the devitrification resistance will worsen, so the total amount is limited to 30% and 35% or less, respectively, and mainly from the viewpoint of devitrification resistance, For each component Na20 is 30%, K20
is 30%, Rb20 is 25%, CsO is 20%, and H
(10 is 20%, CaO is 20%, S'rO is 20%
, BaO is limited to 35% or less. Ta2 05 and Nb2 05 increase the hardness of the glass and improve its durability, but if their total amount exceeds 20%, the glass becomes unstable and becomes less soluble, so they should be limited to 5% and 20% or less, respectively. be done. Si02, Ge02, B2O3,
AjL2 03 , Sb2 03 and In2 03 are 15%, 25%, 30%, 10%, 20% and 1, respectively.
If it exceeds 5%, then La2 03, Y2 03,
When Gd2 03 , Yb2 03 and 1r02 exceed 4%, the glass becomes unstable and becomes less soluble. If Bi203 exceeds 1()%, it will exhibit strong coloring, so it should be limited to less than that. On the one hand, O3 is effective in obtaining a high refractive index, but it is limited to 1% or less because the coloration increases with the increase in its aperture. Ti
02 increases the refractive index of the glass and improves its abrasion resistance, but it increases discoloration if there are many injuries, so it is limited to 20% or less,
It is preferably 10% or less. In addition, As2 03.5b203 is used for purposes such as clarifying and embellishing during melting.
This does not prevent the addition of F, etc.

[Example] Next, a practical composition example (N
01 to No. 32) and the composition examples of Conventional Example 1, Conventional Example 2, and Conventional Example 3 described above are shown in Tables 1 and 2, and a comparison of transmittance is shown in the drawing. Nos., , 51 and N0 in tables and figures
52 and Nα53 indicate conventional example 1, conventional example 2, and conventional example 3, respectively. In addition, in Tables 1 and 2, other oxides include na20, K20, I
tb20, C320, H(10, CaO, 5rO1B
aO, Ta2 05 , Nb2 05 , Si 02
, Ge 02, B2O3, A1203, Sb2 03
, In2 03.1, a2 03, Y2 03 , G
d2 03 , Yb2 03, ZrO2, Bi2 03
, Ti 02 , and WO3, and in each example in the table, the name of the substance is indicated below the number.

These tellurite glasses are made from mixed raw materials (batch)
is placed in a gold or platinum crucible and placed in a melting furnace.
After melting at 700-1200℃, stirring and clarifying to make clean glass without bubbles or striae, it is cast into a press or mold and slowly cooled to room temperature.
Table 3 shows a comparison between some of Examples Nα1 to Nα32 and the conventional example.

Table 3 The wear degrees of Examples No. 016, No. 17, Na29 and No. 31 of the present invention are 400 to 780, while the wear degrees of Conventional Examples No. 51, No. 52 and No. 053 are 1030. 1450, it can be seen that the Delrite glass of the present invention is harder and has better workability than the conventional Chirurai 1-glass. Further, N of the embodiment according to the present invention.

The powder method water resistance measurements of No. 16, No. 17, No. 29 and N (131) are 0.010 to 0.031 wt%, whereas conventional example No. 51, Nα52 and Nα5
The value of 3 is 0.044 to 0.309 wt%, which shows that the tellurite glass of the present invention is superior in durability to the conventional tellurite glass. These measurements of abrasion degree and powder method water resistance are based on the Japan Optical Glass Industry Association standard JO.
It was conducted based on GIS-1975.

The coloring of the glass was determined by spectral transmittance.
Curves in the drawing (29, 51, 52 and 53 indicate the glass of sample Nα in Tables 1 and 2, respectively)
As shown in FIG.
．． 53), it transmits light over a shorter wavelength range,
Moreover, the transmittance at each wavelength is high, and it can be seen that the glass has little coloring.

The thermal characteristics of the tellurite glass obtained in the present invention had a yield point of 280 to 480°C.

[Effects of the Invention] As described above, the tellurite glass of the present invention not only has a high refractive index and less coloring, but also has less wear and processability than conventional tellurite glass. It has excellent properties and durability, and can be used as a variety of optical glasses and as a low-melting glass, and has great practical value.

[Brief explanation of drawings]

The drawing is a characteristic diagram showing the difference in spectral transmittance between an example of the tellurite glass of the present invention in Table 2 and a glass according to the prior art.

Claims (2)

[Claims] (1) In mol%, TeO_2 is 10-85, P_2O
_5 is 1-50, PbO is 1-50, Li_2O is 0
~30, ZnO is 0-40, total amount of Li_2O and ZnO is 1-40, Na_2O is 0-30, K_2O is 0-30, Rb_2O is 0-25, Cs_2O is 0
~20, Na_2 O and K_2 O and Rb_2 O and C
s_ Total amount of O is 0 to 30, MgO is 0 to 20, CaO
is 0-20, SrO is 0-20, BaO is 0-35, M
The total amount of gO, CaO, SrO and BaO is 0 to 35, Ta
_2 O_5 is 0 to 5, Nb_2 O_5 is 0 to 20,
The total amount of Ta_2 O_5 and Nb_2 O_5 is 0 to 2
0, Si O_2 is 0 to 15, Ge O_2 is 0 to 25
, B_2 O_3 is 0-30, Al_2 O_3 is 0-30
10, Sb_2 O_ is 0-20, In_2 O_3 is 0-15, La_2 O_3 is 0-4, Y_2 O_3
is 0 to 4, Gd_2 O_3 is 0 to 4, Yb_2 O_
3 is 0-4, Zr O_2 is 0-4, Bi_2 O_3
is 0 to 10, TiO_2 is 0 to 20, WO_3 is 0 to
A tellurite glass characterized by having a composition of 7. (2) In mol%, P_2O_5 is 1 to 40, TiO
The tellurite glass according to claim (1), wherein _2 is 0 to 10.