JP7264449B2 - Glass structure and manufacturing method thereof - Google Patents

Description

The present invention relates to a glass structure having at least one finely-grooved glass substrate comprising a groove-forming region in which fine grooves are formed and a peripheral region continuous to the outside of the groove-forming region. The present invention relates to a glass structure applicable to microchannel applications.

2. Description of the Related Art In recent years, an optical glass panel for aerial imaging, in which a glass member and a light reflecting film such as a metal film are alternately laminated, has been used. In the optical glass panel for aerial image formation, it is possible to form a stereoscopic image of the subject in the air on the opposite principal surface side by allowing light from the subject to enter from one principal surface side. Such an optical glass panel was generally manufactured by laminating glass substrates on which metal films were formed and cutting the laminated glass substrates with a wire saw or the like.

However, in the above-described conventional manufacturing method, when the laminate is cut, cracks may occur in the glass, or the cut surface may meander.

Therefore, some conventional techniques employ a technique of changing the quality of a portion to be cut by a wire saw with a laser beam (see, for example, Patent Document 1). According to this technology, by guiding a wire saw to a location that has been altered by a laser beam, it is possible to prevent the laminated body from being cut in a meandering manner or cracking. rice field.

JP 2013-220981 A

However, in the prior art as described above, there is a limit to miniaturization of fine glass pieces obtained by cutting. Refinement of the fine glass pieces is indispensable, for example, for achieving high definition in the air display, but in the prior art, there is a limit to high definition in the air display.

Moreover, it is difficult to apply the glass member processed by the conventional technology to uses other than the floating display. Preferably, a versatile glass structure that can be applied to high-definition aerial displays and that can be easily applied to other uses is desired.

SUMMARY OF THE INVENTION An object of the present invention is to provide a glass structure and a method of manufacturing the same, which are applicable to high-definition aerial displays and applicable to uses other than aerial displays.

A glass structure according to the present invention has at least one finely-grooved glass substrate comprising a groove-forming region in which fine grooves are formed and a peripheral region continuous outside the groove-forming region. The glass substrate with fine grooves in this glass structure is provided with fine grooves having a width of 200 μm or less in the groove forming region and having smooth side surfaces. Here, the width means the size of the groove in the transverse direction perpendicular to the longitudinal direction (when the size changes in the depth direction, the maximum value among them).

Here, the smooth surface means a surface free from flaws (cracks) such as those generated by mechanical processing using a spindle, a cutter, or the like, abrasion processing using a laser, or the like. More specifically, the smooth surface means a chemically treated surface having a surface roughness Sa of 1.0 μm or less over the entire surface formed by etching.

In the above configuration, since the glass substrate has fine grooves with a width of 200 μm or less, for example, it is possible to arrange a plurality of fine grooves at a pitch (about 400 μm) that is about twice the groove width. Become. In other words, miniaturization of the pitch of the fine grooves can be achieved more easily than miniaturization of a plurality of fine glass pieces cut as in the prior art. For this reason, it becomes easy to respond to finer details such as an aerial display and a micro flow channel.

The glass structure described above comprises at least two glass substrates with fine grooves, and the glass substrates with fine grooves are bonded to each other through the peripheral edge regions in a state where the fine grooves are perpendicular to each other. is preferred. By adopting such a configuration, an optical glass panel for aerial imaging for a high-definition aerial display is realized. In addition, it is preferable to perform adhesion by a transparent adhesive, an OCA (Optical Clear Adhesive) film, or the like.

On the other hand, it is preferable that the glass structure described above is constructed by laminating finely grooved glass substrates and bonding the finely grooved glass substrate and the transparent support substrate. By adopting such a configuration, a microchannel-forming member having high-definition channels can be realized.

Moreover, the glass structure manufacturing method which concerns on this invention is for manufacturing the above-mentioned glass structure. This glass structure manufacturing method includes a laser processing step of forming a modified line having a property of being easily etched at a position where a fine groove is to be formed by scanning with a laser beam, and etching the modified line. and an etching step of penetrating the fine grooves.

By adopting such a manufacturing method, for example, it becomes possible to form a large number of fine grooves at one time by etching, thereby improving productivity, particularly mass productivity. In addition, by employing the etching process, scratches or the like do not occur during processing, so that the strength of the glass structure increases, and it becomes easy to cope with ultra-thinness.

The diameter of the laser beam is generally about 1 to 100 μm, and if the thickness of the glass substrate is thin, it is possible to form fine grooves with a width almost equal to the diameter of the laser beam. However, as the thickness of the glass substrate to be processed increases, the width of the fine groove tends to slightly increase during the etching process. Therefore, it is preferable to appropriately select the plate thickness of the glass substrate to be used or to select an etching method that makes it difficult for side etching to occur, depending on the required groove width.

According to the present invention, it is possible to realize a glass structure that is compatible with high-definition aerial displays and that can be applied to uses other than aerial displays.

It is a figure showing the outline of the optical glass panel for imaging concerning one embodiment of the present invention. It is a figure which shows an example of the manufacturing method of the optical glass panel for imaging which concerns on one Embodiment of this invention. It is a figure which shows an example of the manufacturing method of the optical glass panel for imaging which concerns on one Embodiment of this invention. FIG. 2 is a diagram showing an example of an etching apparatus used for manufacturing an optical glass panel for imaging; It is a figure which shows the example of planarization of the side surface of a fine groove. It is a figure which shows an example of the manufacturing method of the optical glass panel for imaging which concerns on one Embodiment of this invention. 1 is a diagram showing an outline of a microchannel-forming member according to one embodiment of the present invention; FIG.

An embodiment of the glass structure according to the present invention will be described below with reference to the drawings. The glass structure can be used for applications such as medical microchannel-forming members, industrial microchannel-forming members (such as manifolds of inkjet devices), and optical glass panels for imaging. Here, an example of using the glass structure for an imaging optical glass panel 10 in the field of aerial displays will be described.

As shown in FIGS. 1A and 1B, the imaging optical glass panel 10 comprises a first glass substrate 102 and a second glass substrate 104 each having a plurality of fine grooves 12. . The first glass substrate 102 and the second glass substrate 104 have a groove forming region 20 arranged in the central portion thereof, and a peripheral region 22 arranged so as to be continuous with the outside of this groove forming region.

The first glass substrate 102 and the second glass substrate 104 are adhered or adhered to each other using a transparent adhesive having a refractive index equivalent to that of glass, a transparent double-sided adhesive film, or the like. Bonding or sticking of the first glass substrate 102 and the second glass substrate 104 is performed through the peripheral edge region 22 described above.

The fine grooves 12 of the first glass substrate 102 and the fine grooves 12 of the second glass substrate 104 are arranged perpendicular to each other, as shown in FIG. 1(B). However, since the basic configurations of the first glass substrate 102 and the second glass substrate 104 are the same, in principle, only the first glass substrate 102 will be described below, and the second glass substrate 104 will be described. omit the explanation.

A light reflecting film 14 is provided on the side surface of the fine groove 12 of the first glass substrate 102 . Examples of the light reflecting film 14 include metal thin films with good reflectance such as Al thin films and Ag thin films. Here, an Al thin film is used as the light reflecting film 14, but it is not limited to this. Further, when the width of the fine grooves 12 of the first glass substrate 102 is made as small as possible, a light reflecting effect can be obtained without using the light reflecting film 14 .

In this embodiment, the fine grooves 12 are filled with a resin material (not shown) having the same refractive index as the first glass substrate 102 . However, this configuration is an arbitrary one, and is not limited to such a configuration.

When light from a subject enters one main surface of the imaging optical glass panel 10 described above, the light is emitted from the main surface on the side opposite to the incident side, and an image of the subject is formed in the air in the vicinity thereof. Images can be displayed. By shortening the arrangement pitch of the fine grooves 12, that is, the arrangement pitch of the light reflection film 14, the imaged image can be made higher in definition.

Next, an example of a method for manufacturing the imaging optical panel 10 will be described with reference to FIGS. 2(A) to 2(C) and FIGS. 3(A) to 3(C). First, as shown in FIGS. 2(A) and 3(A), a laser beam is scanned at the position where the fine groove 12 is to be formed on the first glass substrate 102, so that the modified line 122 for forming the fine groove is formed. It is formed.

The type and irradiation conditions of the laser beam are not limited, as long as the position on the first glass substrate 102 where the fine groove is to be formed can be modified to be easily etched. In this embodiment, the laser head irradiates a laser beam oscillated from a short pulse laser (e.g. picosecond laser, femtosecond laser), but for example, a CO ₂ laser, nanosecond laser, etc. may be used. . In this embodiment, the output is controlled so that the average laser energy of the laser beam is approximately 30 μJ to 300 μJ.

The modified lines 122 formed at the positions where fine grooves are to be formed are a plurality of filament layers formed by a laser beam pulse (with a beam diameter of about 1 to 10 μm) emitted from a pulse laser such as a picosecond laser or a femtosecond laser. are arranged, for example, a perforated pattern having a plurality of through-holes or modified layers. The modified line 122 has a property of being etched more easily than other portions of the first glass substrate 102 . Of course, the shape of the reforming line 122 is not limited to this shape, and may have a shape other than this.

It is preferable that the condensing area of the laser beam is appropriately adjusted. Here, the fine grooves 12 can be easily formed by adjusting the laser beam condensing region so as to cover the entire thickness direction of the first glass substrate 102 .

Following the above-described laser processing, as shown in FIG. 4, the multi-panel glass base material 10 is introduced into an etching apparatus 50 and subjected to an etching process using an etchant containing hydrofluoric acid, hydrochloric acid, or the like. Usually, an etchant containing about 1 to 10% by weight of hydrofluoric acid and about 5 to 20% by weight of hydrochloric acid is used, and if necessary, a surfactant or the like is used in combination.

In the etching apparatus 50, while conveying the first glass substrate 102 by the conveying rollers, the main surface of the first glass substrate 102 is brought into contact with the etchant in the etching chamber, thereby etching the first glass substrate 102. is done. In addition, since a cleaning chamber for washing away the etchant adhering to the first glass substrate 102 is provided in the subsequent stage of the etching chamber in the etching apparatus 50, the etchant is removed from the first glass substrate 102. It is discharged from the etching apparatus 50 in this state.

As an example of a method of bringing an etchant into contact with the first glass substrate 102, as shown in FIG. and spray etching. Alternatively, instead of spray etching, as shown in FIG. 4B, a configuration may be employed in which the first glass substrate 102 is transported while being in contact with the overflowing etchant in an overflow type etching chamber 54. It is possible.

Furthermore, as shown in FIG. 4C, dip etching is employed in which one or more first glass substrates 102 housed in a carrier are immersed in an etching tank 56 containing an etchant. is also possible.

By the etching process described above, the modification line 122 of the first glass substrate 102 penetrates and the fine groove 12 is formed. It is possible to form the fine grooves 12 whose width is minimized by the above-described technique. The width of the fine groove 12 can be appropriately adjusted within a range of approximately 5 μm to 500 μm. In this embodiment, the width of the fine grooves 12 is set to 200 μm or less in order to increase the definition of the floating display. Since the arrangement pitch of the fine grooves 12 is about twice the groove width, for example, if the width of the fine grooves 12 is minimized to about 5 μm, the arrangement pitch of the fine grooves 12 can be minimized to about 10 to 20 μm. it becomes possible to

In principle, if the thickness of the first glass substrate 102 is thin, the groove width of the fine grooves 12 can be easily reduced. The reason is that the groove width of the fine groove 12 is slightly increased from the laser beam diameter in the etching process. As a countermeasure against this slight increase, the addition of a fluorine-complexing agent such as titanium oxide in the etching process has revealed that the slight increase in the groove width of the fine groove 12 in the etching process can be suppressed. It's becoming Therefore, the groove width of the fine groove 12 can be adjusted by adding an appropriate amount of a fluorine complexing agent to the etchant as necessary.

Subsequently, as shown in FIGS. 2C and 3C, a light reflecting film 14 is formed on one side surface of the fine groove. Techniques for forming the light reflecting film 14 include vacuum deposition, sputtering, electroless plating, and the like, but other techniques can also be employed.

Prior to the formation of the light reflecting film 14, it is preferable that the surface roughness of the side surfaces of the fine grooves 12 of the first glass substrate 102 is smooth. By the above-described method, the surface roughness Sa of the entire side surface of the fine groove 12 is often several tens of nanometers to several hundred nanometers, as shown in FIG. 5(A).

In order to further reduce the surface roughness Sa of the entire side surface of the fine groove 12, for example, a normal temperature controlled at about 40 to 42° C. containing 35 to 95% by weight of sulfuric acid and 1 to 10% by weight of hydrofluoric acid is used. An additional etching process using an etchant different from the etching process may be used. As a result, as shown in FIG. 5B, the surface roughness Sa of the entire side surface of the fine groove 12 of the first glass substrate 102 can be smoothed to about several nanometers.

Further, in order to further improve the production efficiency of the first glass substrate 102, as shown in FIGS. It is preferable to employ a method of performing laser processing, etching, film formation, etc. on the material 100 and then dividing the material 100 .

For example, a glass base material 100 in which first glass substrates 102 are arranged in a matrix of 4 rows×4 columns as shown in FIG. It is possible to divide. Apart from the scribe-break method, it is also possible to divide by an etching process. When dividing by etching, after covering the first main surface and the second main surface with a protective film, it is possible to divide by removing the portions corresponding to the cut portions in the protective film and etching. is.

So far, an example of using a glass structure having a plurality of finely grooved glass substrates in the imaging optical glass panel 10 of an aerial display has been shown, but the glass structure according to the present invention can be applied to other uses. Is possible.

FIGS. 7A and 7B schematically show a microchannel-forming member as another application example of the glass structure. FIG. 7(A) shows an example in which five first glass substrates 102 are laminated to utilize continuous fine grooves 12 as microchannels. For each first glass substrate 102, it is preferable to use a highly transparent adhesive such as an OCA (Optical Clear Adhesive) film, but the adhesive is not limited to this.

On the other hand, FIG. 7B shows an example in which the first glass substrate 102 and the support glass 110 are bonded together and the outer side of the groove forming region 20 is cut to utilize the fine grooves 12 as microchannels. ing. Glass has chemical resistance equal to or greater than that of PEEK, which is widely used as a chemical-resistant member for forming channels, so it can be used as a channel for introducing various chemical solutions. Is possible. In addition, since the visibility of the microchannel is significantly improved due to the transparency of the glass, even if a problem occurs in the microchannel, it can be easily dealt with.

As described above, it is easier to reduce the groove width of the microgrooves 12 and the pitch of the grooves compared to the technique of forming fine glass pieces by cutting with a wire saw or the like. Therefore, by using the glass structure according to the present invention, it is possible to achieve favorable effects such as refinement of optical panels, micro-channels, and the like.

The description of the above-described embodiments should be considered illustrative in all respects and not restrictive. The scope of the invention is indicated by the claims rather than by the embodiments described above. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and range of equivalents of the claims.

10-optical glass panel for imaging 12-fine groove 14-light reflecting film 20-groove forming region 22-peripheral region 50-etching device 100-glass base material 102-first glass substrate 104-second glass substrate 110 -Support glass substrate 122-Modification line

Claims (3)

A glass structure having at least one finely-grooved glass substrate comprising a groove-forming region in which fine grooves are formed and a peripheral region continuous to the outside of the groove-forming region,
The glass substrate with fine grooves includes fine grooves having a width of 200 μm or less in the groove-forming region, the fine grooves having smooth side surfaces , and
At least two glass substrates with fine grooves are provided,
A glass structure in which glass substrates with microgrooves are adhered or adhered via the peripheral edge region in a state where the microgrooves are perpendicular to each other. 2. The glass structure according to claim 1, wherein said glass substrate with fine grooves is laminated, or said glass substrate with fine grooves and a transparent supporting substrate are adhered or adhered. A glass structure manufacturing method for manufacturing the glass structure according to claim 1 or 2 , comprising:
A laser processing step of forming a modified line having a property of being easily etched at this position by scanning the position where the fine groove is to be formed with a laser beam;
an etching step of penetrating a fine groove by etching the modified line;
A glass structure manufacturing method comprising at least:

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