JP2014234341A - Glass member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass member having higher strength than conventional strengthened glass.SOLUTION: A glass member comprises a glass powder sintered body, and has an ion exchange layer on a surface layer. In the ion exchange layer, it is preferable that the concentration of alkali metal ion or alkaline earth metal ion having a relatively large ion radius is lowered gradually from the surface toward the inside of the glass member, and that the concentration of alkali metal ion or alkaline earth metal ion having a relatively small ion radius is raised gradually from the surface toward the inside of the glass member.

Description

  The present invention relates to a glass member used for a casing, a light diffusing plate, a multilayer wiring board and the like which are constituent members of an electronic component device.

  Conventionally, tempered glass has been used as a casing, a light diffusing plate, a multilayer wiring board and the like which are constituent members of an electronic component device. Examples of the tempered glass include air-cooled tempered or ion exchange treated products of soda lime glass and borosilicate glass.

The air-cooled tempered glass is produced by forming a compressive stress layer on the surface by heating the precursor glass to the softening point or higher and then blowing cooling air at a high pressure. On the other hand, ion exchange tempered glass is produced, for example, by immersing precursor glass in an alkali metal molten salt. Here, an ion exchange reaction between ions having a relatively small ion radius (for example, Na ⁺ ions) in the glass surface layer and ions having a relatively large ion radius (for example, K ⁺ ions) in the molten salt proceeds, so that the glass The volume of the surface layer increases and compressive stress is generated. As a result, the mechanical strength of the glass is improved (for example, see Patent Document 1 or 2).

JP-A-10-182182 JP 2004-99370 A

  As described above, a considerable improvement in strength can be achieved by applying a strengthening treatment to the precursor glass. However, it still cannot be said that the strength is sufficient, and when used as a component part of an electronic component device, there is still a problem that breakage still tends to occur.

  In view of the above, an object of the present invention is to provide a glass member having higher strength than conventional tempered glass.

  The glass member of the present invention is made of a glass powder sintered body and has an ion exchange layer as a surface layer.

  The present inventor has found that the glass powder sintered body is more likely to form a compressive stress layer on the surface layer and has higher mechanical strength than the bulk glass. Although this detailed mechanism is unknown, it is considered that the glass powder sintered body has a grain boundary between the glass powders, so that the molten salt easily penetrates into the interior during the ion exchange treatment. In addition, there is an effect that the ion exchange processing time for obtaining a desired mechanical strength can be shortened.

  Moreover, since the glass member of this invention is comprised from a glass powder sintered compact, unlike bulk glass, it is easy to disperse | distribute a functional ceramic powder etc. inside. It is also easy to form into various shapes.

  In the glass member of the present invention, in the ion exchange layer, the concentration of alkali metal ions or alkaline earth metal ions having a relatively large ion radius decreases from the surface of the glass member to the inside, and the ion radius is relatively large. The concentration of small alkali metal ions or alkaline earth metal ions is preferably increased from the surface to the inside of the glass member.

In the glass member of the present invention, in the ion exchange layer, the K ⁺ ion concentration preferably decreases from the surface of the glass member to the inside, and the Na ⁺ ion concentration increases from the surface of the glass member to the inside.

In the glass member of the present invention, the glass powder contains, in mol%, SiO ₂ 30 to 80%, B ₂ O ₃ 0 to 30%, and Li ₂ O + Na ₂ O + K ₂ O 0.1 to 40%. preferable.

In the glass member of the present invention, the glass powder is a further _{mole%, Li 2 O 0~30%,} Na 2 O 0~30%, K 2 O 0~30%, 0~30% MgO, CaO 0~30 %, SrO 0~30%, BaO 0~30 %, Al 2 O 3 0~30%, and preferably contains 0 to 25% ZnO.

  The glass member of the present invention preferably contains ceramic powder.

  The manufacturing method of the glass member of this invention is characterized by including the process of baking the raw material powder containing glass powder, obtaining a sintered compact, and the process of performing an ion exchange process with respect to a sintered compact.

  According to the present invention, it is possible to provide a glass member having higher strength than conventional tempered glass.

It is a schematic diagram which shows one Embodiment of the glass member of this invention. It is a schematic diagram which shows another embodiment of the glass member of this invention.

  FIG. 1 is a schematic view showing an embodiment of the glass member of the present invention. As shown in FIG. 1, the glass member 1 is plate-shaped. The glass member 1 is comprised from the glass powder sintered compact, and has an ion exchange layer in the surface layer.

Specifically, in the ion exchange layer, the concentration of alkali metal ions or alkaline earth metal ions having a relatively large ion radius decreases from the surface to the inside of the glass member 1 and has a relatively small ion radius. The alkali metal ion or alkaline earth metal ion concentration increases from the surface of the glass member 1 to the inside. Examples of alkali metal ions include Li ⁺ ions, Na ⁺ ions, K ⁺ ions, Rb ⁺ ions, and Cs ⁺ ions. Alkaline earth metal ions include Mg ²⁺ ions, Ca ²⁺ ions, Sr ²⁺ ions or Ba ²⁺ ions.

In particular, in the ion exchange layer, it is preferable that the K ⁺ ion concentration decreases from the surface of the glass member 1 to the inside, and the Na ⁺ ion concentration increases from the surface of the glass member 1 to the inside. With such a configuration, the compressive stress layer is easily formed on the surface layer of the glass member 1.

Examples of the glass powder include SiO ₂ —B ₂ O ₃ —R ′ ₂ O glass, SiO ₂ —B ₂ O ₃ —RO glass, SnO—P ₂ O ₅ —R ′ ₂ O glass, and SnO—P. ₂ O ₅ —RO glass, TeO ₂ —R ′ ₂ O glass, TeO ₂ —RO glass, Bi ₂ O ₃ —R ′ ₂ O glass, Bi ₂ O ₃ —RO glass, etc. (however, R 'Is at least one selected from Li, Na, K, Rb and Cs, and R is at least one selected from Mg, Ca, Sr and Ba). As the glass _{composition, SiO 2, B 2 O 3} , P 2 O 5, Bi 2 O 3 or, preferably any one or more of TeO ₂ is from 10 to 99 mol%, more preferably 12 to 95 mol% It is preferable. When there is too little content of these components, it will become difficult to vitrify.

Among these, SiO ₂ —B ₂ O ₃ —R ′ ₂ O-based glass is preferable because it easily forms a compressive stress layer on the surface layer of the glass member 1 by ion exchange treatment. Examples of the SiO ₂ —B ₂ O ₃ —R ′ ₂ O-based glass include mol%, SiO ₂ 30 to 80%, B ₂ O ₃ 0 to 30%, and Li ₂ O + Na ₂ O + K ₂ O 0.1 to 0.1%. Those containing 40% are preferred. The reason for limiting the glass composition in this way will be described below. In the following description, “%” means mol% unless otherwise specified.

SiO ₂ is a component that forms a glass skeleton. The content of SiO ₂ is preferably 30 to 80%, more preferably 40 to 65%. When the content of SiO ₂ is too small, chemical durability tends to decrease. On the other hand, if the content of SiO ₂ is too large, the melting temperature becomes high, it is difficult to vitrify.

B ₂ O ₃ is a component having a high effect of reducing the melting temperature and improving the meltability. The content of B ₂ O ₃ is preferably 0 to 30%, more preferably 5 to 25%. If the B ₂ O ₃ content is too large, chemical durability tends to decrease.

Li 2 _O is an alkali metal _oxide, Na 2 _O and K _{2 O} are components that are used to form a compression stress layer on the surface layer of the glass member 1 by an ion exchange process. It also has the effect of improving meltability. The content of Li ₂ O + Na ₂ O + K ₂ O is preferably 0.1% to 40%, more preferably 2.5 to 35%. If the total amount of these components is too small, it is difficult to obtain the above effect. On the other hand, if the total amount of these components is too large, it tends to devitrify during molding. _The content of each component of Li 2 O, Na ₂ O and _{K 2} O are each preferably 0-30%, more preferably from 1 to 25%.

In addition to the above components, the following components can be contained in the SiO ₂ —B ₂ O ₃ —R ′ ₂ O-based glass.

Al ₂ O ₃ is a component that affects the ion exchange performance, and the content thereof is preferably 0 to 30%, more preferably 3 to 25%. When the content of Al ₂ O ₃ is too large, there is a tendency that the melting is lowered.

  The alkaline earth metals MgO, CaO, SrO and BaO are components used to form a compressive stress layer on the surface layer of the glass member 1 by ion exchange treatment. It is also a component that improves the meltability by lowering the melting temperature. The content of these components is preferably 0 to 30%, more preferably 0.1 to 20%. When there is too much content of these components, it exists in the tendency for chemical durability to fall.

  ZnO is a component that improves the meltability by lowering the melting temperature. It also has the effect of promoting phase separation. By the phase separation of the glass member 1, an improvement in light diffusion characteristics can be expected. The content of ZnO is preferably 0 to 25%, more preferably 0.1 to 23%. When there is too much content of ZnO, it exists in the tendency for chemical durability to fall.

In addition to the above components, P ₂ O ₅ can be up to 5% in order to improve the meltability or lower the softening point to facilitate low-temperature sintering, and Ta ₂ O _{5 in} order to improve the chemical durability. , TiO ₂ , Nb ₂ O ₅ , Gd ₂ O ₃ , La ₂ O ₃ , Y ₂ O ₃ , CeO ₂ , Sb ₂ O ₃ , SnO ₂ , Bi ₂ O ₃ , TeO ₂ or ZrO ₂ in a total amount of 15 % May be included. Further, Ag ₂ O may be contained for the purpose of imparting optical property control and antibacterial action. Furthermore, when it is desired to emit light from the glass member, luminescent center ions such as Eu, Sm, and Ce may be introduced into the glass powder.

  The composition of the glass member 1 which is a sintered body of the glass powder is also preferably in the above range.

  The glass powder may be a crystalline glass powder. In this case, since crystals are precipitated inside the glass by firing, the mechanical strength of the glass member 1 can be increased, and the thermal expansion coefficient can be controlled. Here, the crystallinity of the glass member 1 is preferably 95% or less. If the degree of crystallinity is too high, the proportion of the remaining glass phase tends to decrease and it becomes difficult to form an ion exchange layer.

The average particle diameter D50 of the glass powder is preferably 0.1 to 100 μm, more preferably 1 to ₅₀ μm. When the average particle diameter D ₅₀ of the glass powder is too small, the amount of pores increases during firing. If the glass member 1 contains many pores, the strength tends to decrease even after ion exchange. In addition, moisture and the like can easily enter the inside, and the chemical durability may be reduced. The preferable porosity in the glass member 1 is 10% by volume or less, particularly 9% by volume or less. On the other hand, even if the average particle diameter D ₅₀ of the glass powder is too large, the pores in the glass member 1 is most generated, strength of the glass member 1 tends to decrease.

In the present invention, the average particle diameter D ₅₀ is a value measured by a laser diffraction method.

  FIG. 2 is a view showing another embodiment of the glass member of the present invention. As shown in FIG. 2, the glass member 1 of the present invention may have a structure in which a ceramic powder 3 is dispersed in a glass matrix 2 made of a glass powder sintered body. The ceramic powder 3 is not particularly limited as long as it is generally a commercially available material, and examples thereof include low-temperature type quartz, low-temperature type cristobalite, alumina, garnet, tetragonal zirconia, garnite, and cordierite. These are used for the purpose of controlling the thermal expansion coefficient and optical characteristics.

  Further, if necessary, glass powder such as quartz glass and borosilicate glass can be contained for controlling thermal expansion characteristics and optical characteristics, and phosphor powder such as YAG phosphor can be contained for controlling light emission characteristics. Further, when it is desired to color the glass member, inorganic pigment ceramic powder such as Co, Mn or Fe can be contained.

  When the glass member 1 contains these ceramic powders, the effect of scattering incident light is further increased, and the light diffusion characteristics are improved. In order to enhance the incident light scattering effect, it is preferable to combine the glass powder and the ceramic powder so that the difference in refractive index is large. Specifically, the refractive index difference (nd) between the glass powder and the ceramic powder is preferably 0.05 to 0.2, and more preferably 0.1 to 0.15. If the refractive index difference is too large, the scattering effect of incident light becomes too high, resulting in a scattering loss, and the transmittance tends to decrease.

The average particle diameter D ₅₀ of the ceramic powder 3 is preferably 0.01 to 100 μm, more preferably 0.1 to ₅₀ μm. When the average particle diameter D ₅₀ of the ceramic powder 3 is too small, the density of the glass member 1 is lost, there is a possibility that a defect of pores and the like occur. On the other hand, when the average particle diameter D ₅₀ is too large, the ceramic powder 3 in the glass member 1 is less likely to be homogeneously dispersed, there is a tendency to cause strength reduction.

  Content of the ceramic powder 3 in the glass member 1 is a volume%, Preferably it is 1-60%, More preferably, it is 2-55%. When there is too little content of the ceramic powder 3, it will become difficult to obtain a desired characteristic. On the other hand, when there is too much content of the ceramic powder 3, the compactness of the glass member 1 will fall and there exists a tendency for mechanical strength to fall. Depending on the required characteristics, a plurality of ceramic powders may be mixed and used.

  The thickness of the glass member 1 is preferably 0.1 to 5 mm, more preferably 0.5 to 1.5 mm. If the thickness of the glass member 1 is too small, the strength becomes insufficient. Therefore, when a compressive stress layer is formed on the surface layer, there is a risk of self-collapse. On the other hand, when the thickness of the glass member 1 is too large, for example, the visible region transmittance is lowered, and there is a tendency that it is difficult to use in applications where translucency is required. In addition, the shape of the glass member 1 is not specifically limited, In addition to plate shape, fiber shape, spherical shape, hemispherical shape, hemispherical dome shape, etc. are mentioned. The glass member 1 may be used after being fused or bonded to the surface of an inorganic substrate such as an alumina substrate, a glass substrate, a YAG ceramic substrate, a translucent ceramic substrate, or a metal substrate and then forming an ion exchange layer. Is possible.

  Next, the manufacturing method of the glass member 1 is demonstrated.

  The glass member 1 is manufactured by a method including a step of firing a raw material powder containing glass powder to obtain a sintered body, and a step of subjecting the sintered body to an ion exchange treatment.

  The glass powder is fired after being preformed as necessary. The preforming method is not particularly limited, and a press molding method, an injection molding method, a sheet molding method, an extrusion molding method, or the like can be employed.

  The firing temperature of the glass powder is preferably equal to or higher than the softening point of the glass powder, and more preferably equal to or higher than the softening point + 50 ° C. If the firing temperature is too low, the glass powder does not sufficiently soften and flow, and pores remain in the glass member 1 and the strength tends to decrease. On the other hand, the upper limit of the firing temperature is not particularly limited. However, if the firing temperature is too high, dissolved gas in the glass is released during firing, and pores are easily generated inside the sintered body, so that the mechanical strength of the glass member 1 is increased. There is a tendency to decrease. Therefore, it is preferable that a calcination temperature is the softening point of glass powder +250 degrees C or less.

As a specific example of the ion exchange treatment for the sintered body, there is a method in which the sintered body is immersed in an alkali metal molten salt to replace the alkali metal ions in the surface layer of the glass member 1 and the alkali metal ions in the alkali metal molten salt. It is done. For example, by immersing a sintered body containing Na ₂ O as a composition in a potassium nitrate molten salt, the Na ⁺ ions having a relatively small ionic radius in the surface layer of the glass member 1 are introduced from the potassium nitrate molten salt. In particular, an ion exchange reaction of K ⁺ ions having a large ion radius proceeds. As a result, an ion exchange layer in which the K ⁺ ion concentration decreases from the surface to the inside of the glass member 1 and the Na ⁺ ion concentration increases from the surface to the inside of the glass member 1 is formed on the surface layer of the glass member 1. . As a result, a volume increase occurs in the surface layer of the glass member 1, a compressive stress layer is formed, and the mechanical strength is improved.

  The temperature of the alkali metal molten salt is preferably in the range of the strain point of the glass powder within ± 150 ° C. If the temperature of the alkali metal molten salt is outside the above temperature range, the ion exchange reaction may not easily proceed.

  In addition, before performing an ion exchange process, you may process by grinding, grinding | polishing, or repressing etc. with respect to a sintered compact as needed.

  EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to these Examples.

(1) Preparation of sample Table 1 and 2 has shown the Example (No. 1-4, 6, 8, 10) and the comparative example (No. 5, 7, 9, 11-13).

First, raw material powder was weighed and mixed so as to have the glass composition shown in the table, and the obtained mixture was melted at 900 to 1600 ° C. for 2 hours in a platinum crucible to be vitrified. Molding the molten glass into a film, and the obtained film-like glass was pulverized by a ball mill and then classified through a sieve of 325 mesh, the average particle diameter D ₅₀ was obtained glass powder 30 [mu] m. In addition, the bulk glass of the same composition was produced separately and the strain point and the softening point were measured. The strain point was measured based on ASTM C336, and the softening point was measured based on ASTM C338.

  Next, the ceramic powder shown in the table | surface was mixed with the glass powder as needed, and it pressure-molded using the metal mold | die, and produced the preform. The preform was fired at the firing temperature shown in the table to obtain a sintered body. By subjecting the obtained sintered body to a polishing process, a rod-shaped sample of 3 mm × 4 mm × 40 mm is used for a three-point bending strength test, and a plate shape of 10 mm × 10 mm and a thickness of 0.2 mm is used for haze rate evaluation. Each sample was prepared. In addition, No. In No. 13, bulk glass was used.

  No. For 1-4, 5, 8, 10, and 13, the obtained samples were subjected to ion exchange treatment. The ion exchange treatment was performed by immersing in potassium nitrate molten salt for 4 hours at the temperature shown in the table.

(2) Measurement of each characteristic For each of the obtained samples, according to the following method, the three-point bending strength, the haze ratio, and the alkali metal ion concentration gradient (surface of the glass matrix in the sample) The presence or absence) was measured or evaluated. The results are shown in Tables 1 and 2.

  The three-point bending strength test was measured based on JIS R 1601.

  The haze ratio was measured based on JIS K7105.

The concentration gradient of alkali metal ions in the surface layer was measured using a glow discharge luminescence surface analyzer (GD-Profiler 2 manufactured by Horiba Seisakusho). Specifically, the concentration profile of each component in the depth direction is prepared by measuring the concentration of Na ⁺ ions and K ⁺ ions in the surface layer of each sample, and when a concentration gradient is observed from the surface to the inside, “ “Yes”, if not recognized, evaluated as “x”.

  The crystallinity was measured using a powder X-ray diffractometer.

(3) Result No. which is an example. In the samples 1 to 4, 6, 8, and 10, a concentration gradient of alkali metal ions was observed on the surface layer. Specifically, the concentration of K ⁺ ions decreased from the surface to a depth of 20 to 40 μm, and the concentration was substantially constant at a deeper location. On the other hand, the concentration of Na ⁺ ions increased from the surface to a depth of 20 to 40 μm, and the concentration was substantially constant at a deeper location. That is, it can be seen that the sample of the example has an ion exchange layer formed of alkali metal ions on the surface layer. In this way, No. 1 as an example. Since the samples 1-4, 6, 8, and 10 have an ion exchange layer on the surface layer, the three-point bending strength was as high as 341 MPa or more.

On the other hand, No. which is a comparative example. In the samples 5, 7, 9, 11 and 12, the K ⁺ ion concentration and the Na ⁺ ion concentration were constant from the surface to the inside, and no concentration gradient was observed. That is, in these samples, an ion exchange layer was not formed on the surface layer. Therefore, these samples had a three-point bending strength as low as 230 MPa or less. In addition, No. In the sample No. 13, a concentration gradient of alkali metal ions was observed on the surface layer, and an ion exchange layer was formed. Three-point bending strength was lower than 10 samples.

1 Glass member 2 Glass matrix 3 Ceramic powder

Claims (7)

  A glass member comprising a glass powder sintered body and having an ion exchange layer on a surface layer.   In the ion exchange layer, the concentration of alkali metal ions or alkaline earth metal ions having a relatively large ionic radius decreases from the surface of the glass member to the inside, and alkali metal ions or alkaline earth having a relatively small ionic radius. The glass member according to claim 1, wherein the concentration of the metal-like ions increases from the surface of the glass member to the inside. The glass according to claim 2, wherein in the ion exchange layer, the K ⁺ ion concentration decreases from the surface of the glass member to the inside, and the Na ⁺ ion concentration increases from the surface of the glass member to the inside. Element. Glass powder, in _{mol%, SiO 2 30~80%, B} 2 O 3 0~30%, and _{Li 2 O + Na 2 O +} K 2 O , characterized in that it contains 0.1 to 40% claim 1 The glass member according to any one of 3. Glass powder, in addition _{mol%, Li 2 O 0~30%,} Na 2 O 0~30%, K 2 O 0~30%, 0~30% MgO, CaO 0~30%, SrO 0~30% _{, BaO 0~30%, Al 2 O} 3 0~30%, and a glass member according to claim 4, characterized in that it contains 0 to 25% ZnO.   The glass member according to claim 1, comprising ceramic powder.   It is a method for manufacturing the glass member as described in any one of Claims 1-6, Comprising: The process of baking the raw material powder containing glass powder, and obtaining a sintered compact, and a sintered compact And a step of performing an ion exchange treatment.