JP2012158498A - Method for manufacturing cleaned glass body, optical element, and optical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for efficiently manufacturing a cleaned glass body the surface of which is treated while suppressing damage of a glass gob, an optical element manufactured from the cleaned glass body manufactured by the method, and an optical instrument equipped with the optical element.SOLUTION: In the method for manufacturing a cleaned glass body by cleaning the surface of a glass gob, cleaning is carried out by immersing the glass gob in a surface treatment liquid, and irradiating the surface treatment liquid with ultrasonic waves of 100 to 200 kHz to for 5 to 100 seconds. It is desirable to generate the ultrasonic wave by an output of ≥100 to ≤600 W.

Description

  The present invention relates to a technique for cleaning the surface of a glass lump.

Conventionally, a technique for treating the surface of a glass block such as a preform or a glass molded body is known. Such surface treatment is generally performed by immersing a glass block in a predetermined aqueous solution. For example, Patent Document 1 discloses that striae is removed by immersing a glass block containing a B ₂ O ₃ component in an acidic or alkaline solution and treating the surface of the glass block.

JP 2005-281124 A

  However, the technique disclosed in Patent Document 1 requires a long time for the surface treatment. Therefore, as a technique for improving the surface treatment efficiency, ultrasonic irradiation to the solution can be considered, but when the glass lump is soft, the surface is likely to be damaged.

  The present invention has been made in view of the above circumstances, a method capable of efficiently producing a glass body to be cleaned which has been surface-treated while suppressing damage to the glass lump, and glass to be cleaned produced by the method. It is an object of the present invention to provide an optical element manufactured from a body and an optical apparatus using the optical element.

  The present inventors have found that by irradiating high-frequency ultrasonic waves, the surface is treated while suppressing damage to the glass lump, and the present invention has been completed. Specifically, the present invention provides the following.

(1) A method for producing a glass body to be cleaned by cleaning the surface of a glass lump,
The cleaning is performed by immersing the glass block in a surface treatment liquid and irradiating the surface treatment liquid with ultrasonic waves of 100 kHz to 200 kHz for 5 seconds to 100 seconds.

  (2) The method according to (1), wherein the ultrasonic wave is generated with an output of 100 W to 600 W.

  (3) The method according to (1) or (2), wherein the surface treatment liquid has a pH of 8 or more and 11 or less.

  (4) A step of immersing the washed glass lump in water and / or an organic solvent and irradiating the water and / or organic solvent with an ultrasonic wave of 100 kHz to 200 kHz for 10 seconds to 120 seconds. The method according to any one of (1) to (3).

  (5) The method according to (4), wherein the ultrasonic wave is generated with an output of 100 W to 600 W.

  (6) The method according to any one of (1) to (5), wherein the glass block has a Knoop hardness of 400 or less as measured with a microhardness meter.

  (7) The glass lump has a wear degree of 600 or less (calculated from a wear mass when being worn while supplying a polishing liquid with a cast iron flat plate loaded with a constant load of 9.8 N) ( The method according to any one of 1) to (6).

  (8) The method according to any one of (1) to (7), wherein the glass block is a preform before press molding or a glass molded body after press molding.

  (9) An optical element manufactured from a glass body to be cleaned manufactured by the method according to any one of (1) to (8).

  (10) An optical apparatus using the optical element according to (9).

  According to the present invention, since the surface treatment liquid in which the glass block is immersed is irradiated with ultrasonic waves of 100 kHz or more and 200 kHz or less for 5 seconds or more and 100 seconds or less, the surface treatment is performed while suppressing damage to the glass block. A glass body can be produced. Further, a glass substrate having a good quality can be obtained in a necessary and sufficient time of 5 seconds or more and 100 seconds or less, and the necessity for performing surface treatment again as in the conventional case is small, so that the production efficiency is excellent.

  Hereinafter, although embodiment of this invention is described, this invention is not limited to this.

  The method for producing a glass body to be cleaned according to the present invention includes immersing a glass lump in a surface treatment liquid, and irradiating the surface treatment liquid with ultrasonic waves of 100 kHz to 200 kHz over 5 seconds to 100 seconds, A step of cleaning the surface of the glass lump. Irradiation with ultrasonic waves having a frequency of 200 kHz or less improves the cleaning efficiency of the glass lump surface, and the surface of the glass lump can be sufficiently cleaned in a relatively short time of 5 seconds to 100 seconds. Moreover, it can suppress that a damage | wound arises on the surface of a glass lump by making the frequency of an ultrasonic wave 100 kHz or more.

  The lower limit of the frequency is more preferably 110 kHz, most preferably 130 kHz, and the upper limit of the frequency is more preferably 190 kHz, and most preferably 170 kHz. The lower limit of the irradiation time is more preferably 10 seconds, most preferably 40 seconds, and the upper limit of the frequency is more preferably 90 seconds, and most preferably 60 seconds.

  The output of the ultrasonic wave is not particularly limited, but if it is too large, the surface of the glass lump tends to be damaged, whereas if it is too small, the cleaning efficiency of the surface of the glass lump may not be sufficiently improved. Therefore, the lower limit of the ultrasonic output is preferably 100 W, more preferably 150 W, and most preferably 200 W. Moreover, it is preferable that the upper limit of the output of an ultrasonic wave is 600W, More preferably, it is 500W, Most preferably, it is 300W.

  The surface treatment solution may be acidic, neutral or alkaline, but is preferably alkaline in terms of detergency. However, if the pH is excessive, the glass lump is easily affected or the time required for removing the surface treatment liquid from the glass lump becomes long. On the other hand, if the pH is excessively small (that is, close to neutrality), the surface treatment is performed. There is a possibility that the efficiency of the above is not sufficiently obtained. Therefore, the upper limit of the pH of the surface treatment solution is preferably 11, more preferably 10.5, and most preferably 9.5. Further, the lower limit of the pH of the surface treatment solution is preferably 8, more preferably 8.5, and most preferably 9.0.

  The composition of the surface treatment liquid is not particularly limited, and may be appropriately selected from conventionally known components so that the glass lump to be used is hardly affected.

  The glass lump after cleaning may be used as it is as a glass body to be cleaned, but since a certain amount of surface treatment liquid may remain, if necessary depending on the use of the glass body to be cleaned, the remaining surface treatment liquid Is preferably removed. Specifically, the washed glass lump may be immersed in water and / or an organic solvent.

  In order to efficiently remove the remaining surface treatment liquid, it is preferable to irradiate water and / or an organic solvent with ultrasonic waves, but it is necessary to suppress damage to the glass lump at that time. Therefore, it is preferable to irradiate water and / or an organic solvent with ultrasonic waves of 100 kHz to 200 kHz for 10 seconds to 120 seconds.

  The lower limit of the frequency is more preferably 110 kHz, most preferably 130 kHz, and the upper limit of the frequency is more preferably 190 kHz, and most preferably 170 kHz. Further, the lower limit of the irradiation time is more preferably 20 seconds, most preferably 60 seconds, and the upper limit of the frequency is more preferably 110 seconds, and most preferably 90 seconds.

  The output of the ultrasonic wave is not particularly limited, but if it is too large, the surface of the glass lump tends to be damaged, whereas if it is too small, the cleaning efficiency of the surface of the glass lump may not be sufficiently improved. Therefore, the lower limit of the ultrasonic output is preferably 100 W, more preferably 150 W, and most preferably 200 W. Moreover, it is preferable that the upper limit of the output of an ultrasonic wave is 600W, More preferably, it is 500W, Most preferably, it is 300W.

  Only one or both of water and the organic solvent may be used. However, it is preferable to use at least an organic solvent in terms of easy drying of the glass lump after this step. The organic solvent may be appropriately selected from those having volatility. Although it does not specifically limit, 1 type (s) or 2 or more types, such as ethyl alcohol, isopropyl alcohol, and ether, are mentioned.

  Such a step of removing the remaining surface treatment liquid is not limited to once, and may be repeated a plurality of times. In the latter case, the conditions for a certain process and the conditions for another process may be the same or different. For example, water may be used in the first step, and an organic solvent may be used in the second and subsequent steps. In the case where the above process is repeated a plurality of times, at least a part of the ultrasonic irradiation may be performed under the above conditions, and the ultrasonic irradiation under the above conditions is not necessarily performed over the entire process.

  In addition, the immersion of the glass block in the surface treatment liquid, water, or an organic solvent is performed from the viewpoint of preventing the glass block from coming into contact with other objects (for example, containers, other glass blocks) and damaging the glass block. It is preferable to perform in a state where the lump is held and the movement is suppressed. Since such a holding member is publicly known, description thereof is omitted. Moreover, you may wash | clean one or several glass lump, and it is preferable to wash | clean a several glass lump from a viewpoint of improving the manufacture efficiency of a to-be-cleaned glass body. Further, the irradiation with ultrasonic waves may be performed according to a conventionally known method using an arbitrary ultrasonic cleaner, appropriately setting the frequency, output, and the like.

  A part or all of the above steps may be performed in the same container, or may be performed in separate containers. The latter is preferable in that the trouble of exchanging the liquid in the container for each step can be saved. Moreover, after all the processes are complete | finished, in order to remove the liquid in which the glass lump was immersed, you may dry a glass lump.

  Thus, according to the method of the present invention, a glass body to be cleaned that has been surface-treated while suppressing damage to the glass lump can be produced, and therefore a glass lump having various characteristics can be used. In particular, it is calculated from the wear mass when it is worn while supplying a polishing liquid in a glass lump having a Knoop hardness of 400 or less measured by a micro hardness tester and a cast iron flat plate loaded with a constant load of 9.8 N. Since a glass lump having a wear level of 600 or less is easily damaged, it can be preferably used in the method of the present invention.

  The upper limit of Knoop hardness is more preferably 390, most preferably 370, and the lower limit is more preferably 330, and most preferably 350. The upper limit of the degree of wear is more preferably 590, most preferably 550, and the lower limit is more preferably 450, and most preferably 500.

  The method of the present invention is useful for various masses of glass. For example, when a preform before press molding is used as the glass lump, dirt attached to the surface is removed during the preform manufacturing process, so that a high-quality press-molded body can be obtained. Moreover, you may process (what is called centering) into a desired outer shape by the method of this invention, using the glass molding after press molding as a glass lump.

  The present invention includes an optical element manufactured from the glass body to be cleaned manufactured by the above method, and an optical device using the optical element. Since the glass body to be cleaned of the present invention is efficiently surface-treated while suppressing damage to the glass lump, it is of high quality and inexpensive. For this reason, the optical element and optical apparatus obtained by using the glass body to be cleaned are also high quality and inexpensive.

<Example 1, Reference Example>
A preform made of phosphate glass (Knoop hardness 370 measured by the above-mentioned method, wear degree 470) is immersed in a 1.0 vol% surface treatment solution (pH about 10) contained in a cleaning tank. The surface treatment liquid was irradiated with ultrasonic waves having a frequency of 170 kHz and an output of 300 W over the time shown in Table 1. Thereafter, the preform was taken out from the cleaning tank, and the surface state was visually observed. The results are shown in Table 1.

(Comparative Examples 1-3)
Except that the frequency was changed to 40 kHz (Comparative Example 1) and 72 kHz (Comparative Example 2) and the ultrasonic irradiation time was changed to 3 seconds, ultrasonic irradiation was performed in the same procedure as in Example 1, The surface condition of was visually observed. The results are shown in Table 1.

In Table 1 and the following table, dirt and scratches were evaluated according to the following criteria.
Dirt: ◎ Dirt was not confirmed at all.
○ Slight dirt was confirmed.
△ Not a little dirt was confirmed.
× Dirt was noticeable.
Scratches: ◎ No scratches were confirmed.
○ Slight scratches were confirmed.
Δ: Not a few scratches were confirmed.
× Scratches were conspicuous.

<Example 2, reference example>
The ultrasonic frequency was set to the value shown in Table 2 and the ultrasonic irradiation was performed in the same procedure as in Example 1 except that the irradiation time was 5 seconds or 100 seconds, and the surface state of the preform was visually observed. Observed. The results are shown in Table 2.

<Example 3>
The surface of the preform was subjected to ultrasonic irradiation in the same manner as in Example 1 except that the ultrasonic frequency and output were set to the values shown in Tables 3 and 4 and the irradiation time was 5 seconds or 100 seconds. The state was observed visually. The results are shown in Tables 3 and 4.

<Example 4>
Except that the surface treatment liquid having a pH shown in Table 5 was used, ultrasonic irradiation was performed in the same procedure as in Example 1, and the surface shape of the preform was visually observed. The results are shown in Table 5.

<Example 5>
The preform after washing in Example 4 (obtained using a surface treatment solution of pH 8, 11, 12) was immersed in pure water contained in a pure water tank, and the frequency was 170 kHz and output to pure water. 300 W ultrasonic waves were applied for 90 seconds. The preform was taken out and immersed again in pure water contained in another pure water tank, and the pure water was irradiated with ultrasonic waves having a frequency of 170 kHz and an output of 300 W for 90 seconds.

  Thereafter, the preform was taken out and immersed in isopropyl alcohol accommodated in an IPA tank, and this isopropyl alcohol was irradiated with ultrasonic waves having a frequency of 170 kHz and an output of 300 W for 90 seconds. The preform was taken out, immersed in isopropyl alcohol accommodated in another IPA tank, and allowed to stand for 5 minutes. Thereafter, the preform was taken out and allowed to stand for 15 minutes in a drying tank in an atmosphere of isopropyl alcohol vapor.

  100 preforms each having been subjected to the above steps were molded with a general press mold to produce a press molded body. When each press-molded body was observed, none were scratched or soiled. However, in the case of a preform obtained using a surface treatment solution having a pH of 12, some of the obtained press-molded products were whitened due to the surface treatment solution remaining in the preform.

Claims (10)

A method for producing a glass body to be cleaned by cleaning the surface of a glass lump,
The cleaning is performed by immersing the glass block in a surface treatment liquid and irradiating the surface treatment liquid with ultrasonic waves of 100 kHz to 200 kHz for 5 seconds to 100 seconds.   The method according to claim 1, wherein the ultrasonic wave is generated with an output of 100 W or more and 600 W or less.   The method according to claim 1, wherein the surface treatment liquid has a pH of 8 or more and 11 or less.   The method further comprises a step of immersing the washed glass lump in water and / or an organic solvent, and irradiating the water and / or organic solvent with an ultrasonic wave of 100 kHz to 200 kHz for 10 seconds to 120 seconds. The method according to any one of 1 to 3.   The method according to claim 4, wherein the ultrasonic wave is generated with an output of 100 W or more and 600 W or less.   6. The method according to claim 1, wherein the glass block has a Knoop hardness of 400 or less as measured with a microhardness meter.   The glass lump has a wear degree of 600 or less (calculated from a wear mass when being worn while supplying a polishing liquid with a cast iron flat plate loaded with a constant load of 9.8 N). 6. The method according to any one of the above.   The method according to claim 1, wherein the glass lump is a preform before press molding or a glass molded body after press molding.   The optical element manufactured from the to-be-cleaned glass body manufactured by the method in any one of Claim 1 to 8.   An optical apparatus using the optical element according to claim 9.