JP2014125395A - Glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide glass which has excellent mass productivity and weather resistance and with which an optical element with desired absorption properties can easily be produced by comprising a light absorbing component.SOLUTION: This glass is characterized by comprising 5 to 70% of Pand 1 to 30% of Sin cation% and Fas anion as an essential component.

Description

  The present invention relates to a glass suitable for a lens of a digital camera, heat ray absorbing glass, IR / UV absorbing glass, and the like.

  Conventionally, phosphate glass has been widely used as optical glass used in electronic devices and the like. Phosphate glass has a high visible light transmittance, and can efficiently absorb light in the near infrared to infrared depending on the composition. Therefore, phosphate glass is widely used in the electronic field as optical elements such as digital camera lenses, heat ray absorbing glass, and IR / UV absorbing glass.

For example, Patent Documents 1 and 2 describe IR absorption glasses made of phosphate glass containing P ₂ O ₅ , Al ₂ O ₃ , alkaline earth metal oxides, and the like. However, since these phosphate glasses have low weather resistance, there is a tendency that problems such as surface alteration occur when used over a long period of time.

Therefore, a fluorophosphate glass having improved weather resistance by containing P ⁵⁺ , Al ³⁺ , alkali metal ions and the like as a cation component and F ⁻ as an anion component has been proposed (for example, patents). Reference 3). By containing a light absorption component such as CuO in the fluorophosphate glass, a glass capable of cutting light of a specific wavelength, such as an IR absorption glass, can be produced.

Japanese Patent Publication No. 2-31013 Japanese Patent No. 3283722 JP 2010-52987 A

  In recent years, electronic devices are becoming thinner and lighter, and electronic components such as IR-absorbing glass used in the electronic devices are also required to be thinner. In order to cut near infrared light sharply even if the thickness of the component is thin, it is necessary to increase the content of a light absorbing component such as CuO. However, as the amount of CuO contained in the fluorophosphate glass increases, vitrification tends to become unstable.

  In addition, there is an increasing demand for IR-absorbing glasses that are used for a long period of time in harsh outdoor environments, such as devices for recognizing the surrounding environment of automobiles and surveillance cameras. Therefore, further improvement in weather resistance is demanded.

  In view of the above, the present invention provides a glass that is excellent in mass productivity and weather resistance and that can easily produce an optical element having desired absorption characteristics by containing a light absorption component. Objective.

The present invention relates to a glass characterized by containing P ⁵⁺ 5-70% and S ^{6 +} 1 1-30% in terms of cation% and containing F ⁻ as an essential component as an anion.

In cation%, Al ³⁺ 0 to 10%, R ⁺ 1 to 50% (R ⁺ is at least one selected from Li ⁺ , Na ⁺ and K ⁺ ), and M ²⁺ 1 to 50% (M ²⁺ is It is preferable to contain (at least one selected from Mg ²⁺ , Ca ²⁺ , Sr ²⁺ , Ba ²⁺ and Zn ²⁺ ).

It is preferable to contain Cu2 ⁺ 0-15%, Fe3 ⁺ 0-5%, Co2 ⁺ 0-5%, and Ce4 ⁺ 0-5% by cation%.

It is preferable to contain 0.001 to 15% of Cu ²⁺ + Fe ³⁺ + Co ²⁺ + Ce ⁴⁺ in terms of cation%.

  In the JOGIS water resistance test, it is preferably grade 1-4.

  The present invention also relates to an optical element comprising any one of the above glasses.

  ADVANTAGE OF THE INVENTION According to this invention, it is excellent in mass productivity and a weather resistance, and the glass which can produce easily the optical element which has a desired absorption characteristic by containing a light absorption component can be provided.

Sample No. in the examples. It is a graph which shows the transmittance | permeability curve of 1 glass.

The glass of the present invention is characterized by containing P ⁵⁺ 5 to 70% and S ⁶⁺ 1 to 30% in terms of cation%, and containing F ⁻ as an essential component as an anion. Thus, if it is a fluorophosphate glass which contains S6 ⁺ as an essential component as a cation component, it will become possible to vitrify stably, even if it contains light absorption components, such as CuO. Furthermore, weather resistance can be improved.

  Below, the reason which limited the composition of the glass of this invention as mentioned above is demonstrated in detail. In the following description of each component, “%” means “cation%” or “anion%” unless otherwise specified.

P ⁵⁺ is an indispensable component for forming a glass skeleton. The content of P ⁵⁺ is 5 to 70%, preferably 7 to 60%, more preferably 10 to 50%, and still more preferably 12 to 40%. When there is too little content of ^{P5 +} , there exists a tendency for vitrification to become unstable. On the other hand, when there is too much content of ^{P5 +} , a weather resistance will fall easily.

S ⁶⁺ is an effective component for improving the weather resistance while maintaining the optical characteristics. There is also an effect of stabilizing vitrification. The content of S ⁶⁺ is 1 to 30%, preferably 5 to 25%, more preferably 5 to 23%, and still more preferably 8 to 20%. If the content of S ⁶⁺ is too small, the above effect is difficult to obtain. On the other hand, when the content of S ⁶⁺ is too large, the volatilization amount at the time of melting increases, which causes variation in characteristics. Also, vitrification tends to be unstable.

F ⁻ is a component having an effect of improving the weather resistance and stabilizing the glass. The glass of the present invention contains F ⁻ as an essential component, and the content thereof is preferably 2% or more, more preferably 5% or more, and further preferably 8% or more. However, if the content is too large, the amount of volatilization at the time of melting increases, causing variation in characteristics. Also, from the viewpoint of the environment, it is not preferable that the volatilization amount of F ⁻ is increased. Therefore, the content of F ⁻ is preferably 70% or less, more preferably 60% or less, and still more preferably 50% or less.

  In addition to the above components, the glass of the present invention may contain the following components.

Al ³⁺ is an effective component for improving the weather resistance. However, when the content is too large, the melting temperature tends to increase. As a result, when a Cu component is included as a light absorption component, the valence of Cu ions tends to be biased toward the reduction side, and the near-infrared absorption tends to be weakened. In view of the above, the content of Al ³⁺ is preferably 0 to 10%, more preferably 0 to 8%, and still more preferably 0.1 to 5%.

R ⁺ (R ⁺ is at least one selected from Li ⁺ , Na ⁺ and K ⁺ ) is a component that stabilizes vitrification. The content of R ⁺ is preferably 1 to 50%, more preferably 10 to 40%, and still more preferably 20 to 35%. If the content of R ⁺ is too small, vitrification tends to become unstable. On the other hand, when there is too much content of R ^<+> , while vitrification will become unstable, there exists a tendency for a weather resistance to fall.

The content of each R ⁺ component is preferably as follows.

The content of Li ⁺ is preferably 0 to 5%, more preferably 0.1 to 10%. When there is too much content of Li ⁺ , there exists a tendency for phase separation and vitrification to become unstable.

Na ⁺ is a component that gives the most stable vitrification region among the R ⁺ components. Therefore, it becomes easy to enjoy the effect of stabilizing vitrification by positively containing Na ⁺ . The content of Na ⁺ is preferably 1 to 40%, more preferably 10 to 35%, and still more preferably 15 to 30%. If the Na ⁺ content is too small, vitrification tends to become unstable. On the other hand, when there is too much content of Na ⁺ , while vitrification will become unstable, there exists a tendency for a weather resistance to fall.

K ⁺ can be contained for the purpose of adjusting the viscosity. However, if the content is too large, vitrification tends to be unstable and phase separation tends to occur. Therefore, the content of K ⁺ is preferably 0 to 10%, more preferably 0 to 8%.

M ²⁺ (M ²⁺ is at least one selected from Mg ²⁺ , Ca ²⁺ , Sr ²⁺ , Ba ²⁺ and Zn ²⁺ ) is also an effective component for stable vitrification. It also has the effect of improving weather resistance. The M ²⁺ content is preferably 1 to 50%, more preferably 10 to 45%, and still more preferably 15 to 40%. When there is too little content of M2 ⁺ , there exists a tendency for vitrification to become unstable. Moreover, there exists a tendency to be inferior to a weather resistance. On the other hand, when the content of M ²⁺ is too large, vitrification tends to be unstable.

The content of each component of M ²⁺ is preferably as follows.

The contents of Ca ²⁺ , Sr ²⁺ , Ba ²⁺ and Mg ²⁺ are each preferably 0 to 20%, more preferably 0.1 to 10%.

Zn ²⁺ is a component that is particularly effective in stabilizing vitrification and improving weather resistance among M ²⁺ . The content of Zn ²⁺ is preferably 1 to 50%, more preferably 10 to 50%, further preferably 15 to 48%, particularly preferably 20 to 45%, and most preferably 23 to 35%.

The glass of the present invention may contain at least one selected from Cu ²⁺ , Fe ³⁺ , Co ²⁺ and Ce ⁴⁺ for the purpose of absorbing light of a predetermined wavelength. The content of Cu ²⁺ + Fe ³⁺ + Co ²⁺ + Ce ⁴⁺ is preferably 0.001 to 15%, more preferably 0.1 to 12%, and still more preferably 1 to 8%. If the content of these components is too small, the above-mentioned effects are difficult to obtain, while if too much, vitrification tends to become unstable.

  The content of each light absorbing component is preferably as follows.

The Cu ²⁺ content is preferably 0 to 15%, more preferably 0.001 to 12%, and still more preferably 0.1 to 8%. By including Cu ^{2+ in} the optical glass of the present invention, near-infrared light can be effectively absorbed. In the presence of S ⁶⁺ , the balance of Cu ion valence is easily shifted to the oxidation side, so that a glass having excellent absorption characteristics in the near infrared region can be easily obtained.

The content of Fe ³⁺ , Co ²⁺ and Ce ⁴⁺ is preferably 0 to 5%, more preferably 0 to 3%, still more preferably 0 to 2%, and particularly preferably 0.1 to 2%.

When a light-absorbing component such as Cu ²⁺ , Fe ³⁺ , Co ^2+, or Ce ⁴⁺ is contained in a normal phosphate glass, vitrification tends to become unstable, but the optical glass of the present invention does not vitrify. Since a predetermined amount of S ⁶⁺ to be stabilized is contained, there is an advantage that vitrification is not likely to be unstable even if the above components are contained.

W ⁶⁺ has an effect of stabilizing vitrification and improving weather resistance. The content of W ⁶⁺ is preferably 0 to 5%, more preferably 0 to 2%. When there is too much content of ^{W6 +} , there exists a tendency for vitrification to become unstable or the transmittance | permeability of visible region falls.

In addition, Bi ³⁺ , La ³⁺ , Y ³⁺ , Gd ³⁺ , Te ⁴⁺ , Si ⁴⁺ , Ta ⁵⁺ , Nb ⁵⁺ , Ti ⁴⁺ , Zr ⁴⁺ or Sb ³⁺ are included in a range not impairing the effects of the present invention. It doesn't matter. Specifically, the content of these components is preferably 0 to 3%, more preferably 0 to 1%.

  The liquidus temperature of the glass of this invention becomes like this. Preferably it is 700 degrees C or less, More preferably, it is 690 degrees C or less. If the liquidus temperature is too high, vitrification tends to be unstable and mass production tends to be difficult.

  The glass of the present invention is preferably grade 1 to 4 in the JOGIS water resistance test. Thereby, even when used over a long period of time, it is possible to obtain a glass with little deterioration such as erosion due to burning or weathering.

  Next, a method for producing an optical element such as an optical lens using the glass of the present invention will be described.

  First, after preparing a glass raw material so that it may become a desired composition, it fuse | melts at 700-1000 degreeC in a glass melting furnace using a platinum crucible. Next, a glass block is once produced by casting, and an optical element is obtained by grinding, polishing, and washing.

  Hereinafter, although the optical glass of this invention is demonstrated in detail based on an Example, this invention is not limited to these Examples.

(1) Preparation of each sample Table 1 shows the Example (No. 1-8) of this invention, and a comparative example (No. 9-11).

  Each sample was produced as follows.

  First, the glass raw material prepared so that it might become the composition of Table 1 was thrown into the platinum crucible, and it melted so that it might become homogeneous at 800-900 degreeC. Next, the molten glass was poured onto a SUS plate, cooled and solidified, and then annealed at 300 to 350 ° C. to prepare a sample.

(2) Evaluation of each sample About the obtained sample, liquid phase temperature and a weather resistance were measured or evaluated by the following method. The results are shown in Table 1. In addition, No. FIG. 1 shows a transmittance curve obtained by measuring the transmittance of each sample at each wavelength.

  As the liquidus temperature, the sample was allowed to stand for 3 hours in a melting furnace with a temperature gradient, and the highest temperature at which crystals were observed was adopted.

  The weather resistance was evaluated as follows. The surface of the sample cut out to a size of 25 × 30 × 5 mm was mirror-polished with diamond powder to prepare a sample for weather resistance test. After the sample for weathering test was allowed to stand in an environment of temperature 60 ° C. and humidity 90% for 3 days, the surface condition was confirmed. What was seen was evaluated as "x". Moreover, the water resistance according to JOGIS was also evaluated separately.

  The transmittance was measured using a UV3100PC manufactured by Shimadzu Corporation by preparing a 25 × 30 × 1 mm sample whose surfaces were mirror-polished.

  As is apparent from Table 1, No. 1 as an example. Samples 1 to 8 had a low liquidus temperature of 680 ° C. or lower, and vitrification was stable. Moreover, all were excellent in the weather resistance. On the other hand, No. which is a comparative example. All the samples of 9 to 11 were inferior in weather resistance. No. Samples 9 and 11 had a high liquidus temperature of 720 ° C. or higher, and vitrification was unstable.

  The glass of the present invention is used for optical camera applications such as digital camera lenses, CCD cover glasses, heat ray absorbing glasses used in CCDs and CMOSs, and IR / UV absorbing glasses, visibility correction filters, and color adjustment filters. Is possible.

Claims (6)

A glass characterized by containing P ⁵⁺ 5 to 70% and S ⁶⁺ 1 to 30% in terms of cation%, and containing F ⁻ as an essential component as an anion. In cation%, Al ³⁺ 0 to 10%, R ⁺ 1 to 50% (R ⁺ is at least one selected from Li ⁺ , Na ⁺ and K ⁺ ), and M ²⁺ 1 to 50% (M ²⁺ is 2. The glass according to claim 1, comprising at least one selected from Mg ²⁺ , Ca ²⁺ , Sr ²⁺ , Ba ²⁺ and Zn ²⁺ . Glass according to claim 1 or 2, characterized in that it contains, in terms of cation%, Cu2 ⁺ 0-15%, Fe3 ⁺ 0-5%, Co2 ⁺ 0-5%, and Ce4 ⁺ 0-5%. . The glass according to claim 1, wherein the glass contains 0.001 to 15% of Cu ²⁺ + Fe ³⁺ + Co ²⁺ + Ce ⁴⁺ in terms of cation%.   The glass according to any one of claims 1 to 4, which has a grade of 1 to 4 in a JOGIS water resistance test.   An optical element comprising the glass according to any one of claims 1 to 5.