JPS62100451A - Glass composition suitable to produce glass having refractive index gradient - Google Patents

Abstract

PURPOSE:To obtain the titled glass having less tendency for forming a colloidal Ag<+> ion and for generating devitrification while dissolving the titled composition by incorporating prescribed amounts of MgO or ZnO and Al2O3, Nb2O5 or WO3 to a P2O5-Ag2O type glass. CONSTITUTION:The titled composition is produced by compounding starting materials, melting is and effecting vitrification so as to obtain the titled glass having the following composition, namely 30-60% P2O5, 3-50% Ag2O, 20-55% Ag2O+Li2O+Na2O+K2O, 3-30% MgO+ZnO, 3-35% MgO+ZnO+SrO+BaO, 2-30% Al2O3+Nb2O5+WO3, 0-2% each Rb2O, Cs2O, PbO or MnO, and 0-1% Y2O3, Sb2O3, As2O3, ZrO2, Ta2O5, B2O3 or SiO2 by mol. The obtd. glass having the large refractive index gradient can be produced in a short period by dipping said glass in a molten salt contg. a monovalent alkaline metal ion, etc., to ion-exchange it.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a glass composition suitable for producing a glass body having a large refractive index ^11 by ion exchange.

Techniques for the Eye] The ion exchange method is known as one of the 7j methods for forming a refractive index gradient in a glass body. This method (well, it has a great effect of increasing the lid refractive index of glass 1-1+C8+, T
l, △0+I [Which one contains a negative cation A (hereinafter referred to as △ ion), but has a cis form, and Na'', K'', which has a smaller force contributing to the Eve refractive index than A ion. Using a molten salt containing valent alkali metal ions (hereinafter referred to as 1 and 13 ions), the glass body of -1- is immersed in this molten salt, and both △ and 13 ions are mixed into the phase n. For example, if a l:1 rod (cylindrical) glass body is treated with this method, 1 ill! is exchanged symmetrically about the central axis of the rod, as shown by the equation (1). A refractive index gradient can be formed in a rad-like glass body.

rl(r)2-r1o2(1-02r2) (1) where, n(r): refractive index at geothermal heat a distance IIItr in the radial direction from the central axis no: refractive index of central axis 1 q: refraction Weight division A11 constant And, if you choose a slab-like glass body or a spherical ganic body instead of a rod-shaped glass body, J is used for the ion exchange method described in 1 above. The body has a refractive index gradient that is symmetrical to the center plane, and the spherical glass body has a refractive index gradient that is symmetrical to the center point.
1 refractive index gradient is formed respectively [! can be done.

By the way, the glass bodies used in the ion exchange method are organized according to the type of A ions, as described in Japanese Patent Publication No. 47-816 and No. 4
γ-822 February, fi+J 57-18843 January's 41 glasses including T1 listed in each publication, and the equity Itn
47-816 C8-containing '4j described in Q publications etc.
It is broadly divided into glass and L+I-containing glass described in Japanese Patent Application Laid-Open No. 58-125632. Among these, the open [1 number (N, △,) is 0.
It is possible to produce lenses with excellent light-concentrating properties that can be applied to LD light sources and optical disks. Limited to glass containing

But 1-! In No. 2, green bamboo is extremely strong, causing difficulties in manufacturing, drying, and handling.

N, A, -no (1ro (2) where: no: lI center human refractive index j'Q: rl radius (]: refractive index, AI)
21. (6) P1063J, 1. , C0IItaZ
According to et al., optical glass 1-i I'll
it%, 47.9P20b, 1
9.8N a 20, 7.7 to 20.
3.1Δ (1203, 15,4-i i 02 composition, tiit refractive index is 1.61) is immersed in a molten salt containing A(]4 ion, Na+
It has been shown that a large refractive index difference of 0.2 or more can be obtained when ion exchange is performed between ions and He○+ ions in a molten salt. W1 holds that lenses of N, Δ, 05 or more can be manufactured by an ion exchange treatment in which the A020-containing gas system is immersed in a molten salt containing (ffi-, Na salt).

1. Brahma tries to solve it! Problem 1: However, glass containing a large amount of Δ020
During melting, A(]4 ion becomes -1[1 ide and becomes black in color), and there are also problems in terms of stability of the glass, such as devitrification.

This invention is based on Pz 0s-AQ? By blending an appropriate amount of R'O (M (JO or z no > O J, and ■ Rx Oy (A 1203, N b 20 b or WO3) with 0 series glass, 〇+ ions can be added to the 0 series glass during melting. 0.2 to 0 with a relatively short ion exchange treatment without causing 111 id formation or devitrification.
To provide a glass composition capable of manufacturing lenses of about 8 in diameter.

[Solving Problems J, I: Meno-F Stage] The glass composition of the present invention has P2O530-60 A020 3-50 Li 200-2O Na20 0-40 and 200-3 in mol%.゜ACJ? 0+L120-1-Nap O+-20 2
0~! 15M0O□~3゜z no □~3゜M (JO-1-Zn03~30 SrOO~10 tla00~10 MQO1-ZnO+5r01-13a0 3~35
△ff? Ox O~3O Nbp060~30 WO:i 0~30 A! 203]-Nb20b10W03 2~301 b20 Q~2 C820Q~2 1' b 0 0~2 Mn(') 0~2 Y2 03 0~1 St)z030~1 A82 03 0~1 ZrO20~1 Ta ? 05 0~1 13203 0~1 3102! It is characterized by having a composition consisting of Q~1, hereinafter),
In-state limited 3 of each ingredient! l! +b is as follows.

P2O5 is a glass forming oxide with a content of 30
If it is less than %, the glass becomes unstable and devitrification tends to occur. On the other hand, if it exceeds 60%, the chemical durability of the glass deteriorates, and it becomes susceptible to devitrification or erosion during ion exchange treatment. Therefore, P2O5 content (130~6
0%, preferably 35 to 50%.

AO20 is a component that provides a high refractive index to glass and forms a diffraction index gradient within the glass through ion exchange.
Although the number becomes large, if it exceeds 50%, devitrification and I[1-id formation are likely to occur, and furthermore, the chemical durability of the glass deteriorates. Moreover, if it is less than 3%, the numerical aperture of the obtained lens will be around 0.2 to 0.2, which is not practical. Preferred Δ(120f
t is 5 to 40%, and in order to make the number of lenses larger than 0.5 culm 1, 8020 fli is 1
It is necessary to keep it below 0%.

10- L l 20, NazO and Ni 20 are between the lenses.
-1 Although it does not have any special effect on improving the number,
AO? When coexisting with O, it works to improve the devitrification property and scientific durability of glass due to the mixed alkali effect. However, the content of L i 20, NazO and Ni 20!11 taste exceeds 20%, 40%, and 30%, respectively,
A [J t O+ L i 20 + N a 20
When +K 20 &j exceeds 55%, the devitrification resistance and chemical durability deteriorate. Also, Δ(320→
When LI20 and Na2O+ contain less than 20% of 20Si, devitrification tends to occur. Preferably 1.12 (1 brew 0-10%
, NazO & 10~30%, K20&lO~20%, AC120-ILiz O+Naz O+KP o
The suspension is 25-45%.

MGO and ZnO impair the function of increasing the refractive index of △g20<1<, and improve the devitrification resistance and chemical durability of glass1! , and describes the function of preventing AQ+ ions from becoming co-lids. However, M) OtenZn0ffi is 3%
This effect is small for non-vA'c, and on the contrary, M OOA'3
J, content of ZnO alone or tvlo.

When 10Z n Oti exceeds 30%, molten hot stone becomes 13
Since the temperature is as high as 50°C or higher, A(12(')J) becomes easily volatilized and devitrified. Preferably, M o
0itO~20%, ZnOM(')-20%, Mo(
)+7n(') amount is 5 to 20%.

SrO and P a O are less effective than Mho and ZnO, but like Mho and lnO, they work to improve the devitrification resistance and chemical durability of glass. However, SrO and B a OI ( If the flavor content exceeds 10% or Mo
When O+lnO+-8ro+f3aom exceeds 35%, devitrification tends to occur. Preferably 5r010-5%, R
aO&tO~5%, M001ZnO+SrO+f3aO
iM is 5-25%.

Aff203, Nb2O5 and WO2 are used to increase the combined content of A by 2% or more.
It is important to increase the numerical aperture of the lens obtained from the 20-P20Ii series glass, improve the chemical durability of the glass, and prevent the formation of 21[]ide of the 20-P20Ii-based glass. However, if the total amount of these three limits is less than 2%, the chemical durability of the glass will be poor, and if it is too large, the melt level will become high, which will affect the solubility of the glass material. The contents of the contents are J, Bi△ρp 03 +N
The first period of b2Oraji W 03 Kasen will be 30%. Preferably Aj! zO: + hanging 0~20%, Nb2O5 amount 0~
20%, WO2lo-10%, Affz 031-Nb
20s +W03 ff15~20%'l'Al.

In addition, the glass composition of the present invention may contain the following components that stabilize the glass within the range that does not adversely affect the properties v1 of Get Guns. .

Rh 20;0 to 2% C3zO:()~
2%PbO; 0~2% Mno; 0~2%/r
O2; 0-1% Y2O3; 0-1% 1-ap Os
: 0-1% 5b203; 0-1% AS203;
O~1% B2O3:O~1%SiO? : 0 to 1% [Example 1 1nyl% display, Ag2030%, 7n015%, 8g
? 035%, Nb20b 5%, r-'20s 4
Glass fl; having a composition of 5% was heated to 1.150°C in an 8102 crucible, and stirred for 1.1 hours during melting. After melting for a total of 5 hours, it was poured into a mold. Pour/
After heating at 380 DEG C. for 2 hours, the mixture was cooled down to room temperature in a furnace to obtain a glass block. A 2.5avφ rod (PI
41) was cut out and trimmed. The resulting lot had a mole% composition of NF12SO437%, K280421%,
7nS0442%Nial'fAB 1105℃(7)f
7 in f[1al (hereinafter referred to as -1-1 [molten salt ■])
After soaking for 2 hours and performing ion exchange treatment, a thin piece of turtle about 50μ thick was cut out perpendicularly to the axial direction from this one piece, and using an interference microscope, N a : l
) line, the refractive index phase distribution was measured and found to be in good agreement with the ideal refractive index distribution determined from the above equation (1).

Thus, the refraction weight 'ffi T, number (J-0,28(
Ill-'), listening [1 number N, △.

= 0.6, a good 1-1 lens was obtained.

In addition, a lens [] was obtained in the same manner as in Example 10 from the glass composition of the present invention whose composition was melted at a temperature of 1,050°C to 1,250°C. The glass composition, the ion exchange treatment f+, and the performance of the Lott lens are summarized in the first part.
Shown in the table. In addition, in all the examples, the diameter of the rod is 2
．． 5+u++φ, and NaN0+ molten salt or the above molten salt 1 was used for the ion exchange treatment. (Blank above) [Advantageous Effects of the Invention 1] If the glass composition of the present invention is used, the glass can be melted without causing the :':I +:]idization or devitrification of AG" ions, and the Na salt can be dissolved. By immersing it in molten salt, etc., and performing ion exchange, it is possible to reduce the number of N in a relatively short time.
, A, == 0.2 to 0.8 (in the case of rod lenses) can be manufactured.

Furthermore, the A(320 raw material) has extremely less tropism than the RF20 raw material, and has the excellent effect of not causing any difficulty in manufacturing or handling.

Sender: Hoya Co., Ltd. 161 morning of 161

Claims (1)

[Claims] 1 mol% of P_2O_5 3
0~60 Ag_2O3
~50 Li_2O 0
~20 Na_2O
0～40K_2O
0~30 Ag_2O+Li_2O+Na_2O+K2_O 2
0~55 MgO
0~30 ZnO
0~30 MgO+ZnO
3-30 SrO
0~10 BaO
0~10 MgO+ZnO+SrO+BaO
3～35 Al_2O_3
0~30 Nb_2O_5
0～30 WO_3
0~30 Al_2O_3+Nb_2O_5+WO_3
2~30 Rb_2O
0~2 Cs_2O
0-2 PbO
0-2 MnO
0～2 Y_2O_3
0~1 Sb_2O_3
0~1 As_2O_3
0~1 ZrO_2
0~1 Ta_2O_5
0～1 B_2O_3
0~1 SiO_2
A glass composition suitable for producing a glass body having a refractive index gradient by an ion exchange method, characterized by having a composition consisting of 0 to 1. 2 mol% P_2O_5 3
5~50 Ag_2O 1
0~40 Li_2O
0~10 Na_2O
0～30K_2O
0~20 Ag_2O+Li_2O+Na_2O+K_2O 2
5-45 MgO
0~20 ZnO
0~20 MgO+ZnO
5-20 SrO
0~5 BaO
0~5 MgO+ZnO+SrO+BaO
5~25 Al_2O_3
0~20 Nb_2O_5
0～20 WO_3
0~10 Al_2O_3+Nb_2O_5+WO_3
5. The glass composition according to claim 1, which is suitable for producing a glass body having a large refractive index gradient by an ion exchange method.