JP2003192385A - Glass-ceramics and temperature-compensated member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide glass-ceramics that have a negative coefficient of thermal expansion and can be stably produced in composition and physical properties at a low cost, and to provide a temperature-compensated member. <P>SOLUTION: The glass-ceramics comprises 40-70% of SiO<SB>2</SB>, 10-42% of Al<SB>2</SB>O<SB>3</SB>, 1-13% of Li<SB>2</SB>O, 0-5% of B<SB>2</SB>O<SB>3</SB>, more than 4% to less than 10% of P<SB>2</SB>O<SB>5</SB>, 0-2% of ZrO<SB>2</SB>and 0.5-5.5% of TiO<SB>2</SB>+ZrO<SB>2</SB>, by mass. The glass-ceramics has a main crystal phase comprising at least one or more selected from the group consisting of β-eucryptite (β-Li<SB>2</SB>O-Al<SB>2</SB>O<SB>3</SB>-2SiO<SB>2</SB>), a β-eucryptite solid solution (β-Li<SB>2</SB>O-Al<SB>2</SB>O<SB>3</SB>-2 SiO<SB>2</SB>solid solution), β-quartz (β-SiO<SB>2</SB>) and a β-quartz solid solution (β-SiO<SB>2</SB>solid solution). The glass-ceramics has a coefficient of thermal expansion in a temperature range from -40°C to +80°C of -5×10<SP>-7</SP>to -90×10<SP>-7</SP>/k. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can be used in a wide range of applications in the fields of information and communication, energy, electronics, etc., and particularly in the field of optical communication, a part of a device including an optical fiber such as a fiber grating and a connector. The present invention relates to a glass-ceramic having a negative coefficient of thermal expansion and providing temperature compensation to a device, and a temperature compensation member using the same.

[0002]

2. Description of the Related Art Currently, optical fibers are widely used in the field of optical communication. Optical fiber related devices are required to have no adverse effect on the characteristics of the optical fiber itself due to temperature.

For example, an optical fiber connector is used as an input / output terminal of an optical transmission device or an optical measuring device, or as a connector for connecting optical cables within an optical communication line. Such devices for fixing, connecting or protecting optical fibers are combined with materials having a desired coefficient of thermal expansion in order to prevent strain due to expansion / contraction of the device due to temperature change from adversely affecting the optical fibers. It is necessary to devise such as.

Further, the use of the fiber grating is expanding as a device for performing dispersion compensation, wavelength stabilization of a semiconductor laser, etc. by utilizing a wavelength selection characteristic of a narrow band in a wavelength division multiplexing communication system. However, it is known that the central wavelength has temperature dependence because the effective refractive index of the core portion changes with temperature. Therefore, even in such a fiber grating, it is required to reduce the influence of temperature change as much as possible.

Further, in order to prevent the generation of strain and internal stress caused by a temperature difference, not only in the fields related to optical fibers but also in various devices and equipment used in the fields related to energy and information, etc. It is possible to adjust the coefficient of thermal expansion of devices and precision parts that make up equipment, equipment, etc. to appropriate values.
Materials that can satisfy strength, thermal stability and the like are required.

Conventionally, materials suitable for various devices in terms of temperature change as described above are ceramics, glass ceramics, and glass because of their high heat resistance and small coefficient of thermal expansion. And metals are used.

However, these materials have a large coefficient of thermal expansion, that is, they have the property of expanding when the temperature rises, and many of the other materials used for devices together with these materials have a positive coefficient of thermal expansion. Therefore, it is not necessarily the optimum material for preventing the influence of the temperature change of the entire device. Therefore, a material having a negative coefficient of thermal expansion that cancels a large positive coefficient of thermal expansion, that is, a material having a property of contracting when the temperature rises is desired as a material that resists a temperature change.

However, the above-mentioned material having a negative coefficient of thermal expansion tends to have many microcracks as the coefficient of thermal expansion goes in the negative direction, and sufficient mechanical strength cannot be obtained. Also, by impregnating with an organic low-viscosity adhesive, the original negative expansion coefficient of ceramics is canceled out,
Since a desired coefficient of thermal expansion cannot be obtained, it cannot be used as the temperature compensation material as described above. In order to solve such a problem, a densified material which is not impregnated with a grinding liquid or an adhesive and has a more negative expansion is desired.

[0009]

Materials having a negative coefficient of thermal expansion are generally β-eucryptite, β-eucryptite solid solution, β-quartz and β-quartz solid solution, or Li ₂ containing the crystals. O-Al ₂ O ₃ -SiO ₂
System _{ceramics, Li 2 O-Al 2 O} 3 -SiO 2 based glass _{ceramics, ZnO-Al 2 O 3 -SiO} 2 based glass ceramics, lead titanate, titanium hafnium, zirconium tungstate, inorganic substances such as tungsten tantalum Are known

Japanese Patent Publication No. 2000-503967 discloses that
Non-thermosensitive optical elements and methods of making the same are described. The device consists of a negative expansion substrate and an optical fiber having a grating attached to the surface of the substrate. The optical fiber reflection grating is bonded to the negative expansion substrate, so that the change of the central wavelength of the grating is 1.9 when it is not bonded.
What was nm was suppressed to 0.2 nm.
The negative expansive substrate is made of glass ceramics having β-eucryptite crystal and has a coefficient of thermal expansion of −20 × 10 ⁻⁷ to −100 × in a temperature range of −40 to 85 ° C.
It is 10 ⁻⁷ / K, and the thermal expansion hysteresis is suppressed to 20 ppm or less.

However, the glass-ceramic used here contains a large number of microcracks in order to obtain a negative coefficient of thermal expansion, and the crystal grain size is larger than 5 μm to form the microcracks. Such materials do not have sufficient mechanical strength, and are easily impregnated with chemicals during processing. In addition, if an organic adhesive with low viscosity is used because it contains microcracks, the organic adhesive with a large coefficient of thermal expansion is impregnated into the microcracks, and the negative thermal expansion of ceramics is canceled out. The desired coefficient of thermal expansion cannot be obtained.

The crystal phase contains Al ₂ TiO ₅ . Al
₂ TiO ₅ has a remarkable thermal expansion anisotropy, which causes hysteresis in the thermal expansion and contraction curve of the sintered body, the results of repeated measurements do not generally match, and the presence of cracks is essential, so the strength is It is known to be difficult to grow. Furthermore, in the manufacturing process, unless the glass body is heat-treated at 1300 ° C. for at least 3 hours in order to crystallize, a sufficient negative thermal expansion coefficient is not obtained, and the manufacturing cost becomes high.

Japanese Patent Laid-Open No. 2000-313654 discloses that
By burning a crystal powder, a glass powder or the like to generate a large number of microcracks in a crystal grain boundary, -30 × 10
^A temperature compensating member made of a ceramic fired body having a negative coefficient of thermal expansion of ⁻⁷ to −85 × 10 ⁻⁷ / K is disclosed. However, fired ceramics have a relatively large particle size, and
Since micro cracks are generated, the thermal expansion coefficient changes greatly when impregnated with grinding fluid, adhesive, etc.,
Practical application is difficult.

Japanese Unexamined Patent Publication (Kokai) No. 2-208256 discloses ZnO-Al ₂ O ₃ -SiO ₂ -based low thermal expansion ceramics whose main crystal phase is β-quartz solid solution and / or zinc petalite solid solution. However, even if the ceramic has the lowest coefficient of thermal expansion, as seen in the examples, -2.15 × 10 ^{−6 /} K (−21.5 × 10)
^-7 / K), and it is hard to say that it has a sufficiently low negative thermal expansion coefficient.

Further, since this ceramic contains a large amount of ZnO component which easily sublimes at high temperature, in the above publication, long-time melting is not preferable when forming the parent glass (original glass). As described and seen in the examples of the above publication, the melting time is extremely short at 10 minutes. However, in such a short time, even if the temperature is high, the SiO ₂ and Al ₂ O ₃ components are not sufficiently melted and remain unmelted, so that a homogeneous parent glass cannot be obtained, and such a heterogeneous parent glass is not obtained. Even if glass is crystallized, homogeneous ceramics cannot be obtained.

If the glass is melted, the unmelted residue can be eliminated by melting it for several hours as usual, but in that case, the ZnO component sublimes and the composition of the parent glass fluctuates. However, homogeneous ceramics cannot be stably obtained. In addition, the melting temperature of the above-mentioned example is as high as 1620 ° C., which increases the manufacturing cost.

US Pat. No. 5,694,503 also provides a package in which an optical fiber having a refractive index grating is attached to a support member having a negative coefficient of thermal expansion. As the negative expansion material, a composition based on Zr-tungstate or Hf-tungstate is used, and ZrW ₂ having a coefficient of thermal expansion of −4.7 to −9.4 × 10 ⁻⁶ / K is used. Adjust O ₈ to -9.4 × 10 ^-6 / K
Are getting the ingredients. It is said that by using this material as a supporting member and fixing an optical fiber with appropriate stress applied thereto, it is possible to eliminate a change in wavelength due to a temperature change.

However, in the case of materials such as ZrW ₂ O ₈ and HfW ₂ O ₈ , in order to adjust the coefficient of thermal expansion, Al in powder state is used.
₂ O ₃ , SiO ₂ , ZrO ₂ , MgO, CaO, Y ₂ O ₃ and other materials having a positive coefficient of thermal expansion are appropriately added to the mixture to form a sintered body. It is hard to say that it is suitable for mass production. Moreover, since different materials must be mixed, appropriate techniques and equipment are required, and the materials are not always homogeneous. In addition, ZrW ₂ O ₈ and HfW ₂ O ₈ undergo a phase transition near 157 ° C. and the thermal expansion curve shows a bend, so it cannot be said that they are thermally stable in a wide temperature range. .

Other substances having a negative coefficient of thermal expansion are disclosed in WO97 / 14983 and JP-A-10-90.
A liquid crystal polymer is described in Japanese Patent No. 555. However, since the liquid crystal polymer is a crystalline resin, the crystal orientation is strong, and there is a problem such as warpage in an injection molded product. Also, the thermal expansion coefficient in the orientation direction is −100 × 10 ⁻⁷
/ K having a very large negative value, such as about / K, has the drawback that the coefficient of thermal expansion other than the orientation direction has a large positive value, and the physical properties such as bending strength and elastic modulus also greatly differ depending on the direction. , The material is difficult to use for the device.

As described above, the conventional materials having a negative coefficient of thermal expansion have some problems, so that they are not often used in the fields of optical communication, energy-related fields, information fields and other various fields. The reality is that it has not been done.

In view of the above situation, an object of the present invention is to grind due to its fineness in a temperature range of -40 ° C to + 80 ° C, which is a general temperature range used in the fields of optical communication, energy-related fields, information fields and the like. It is an object to provide a glass ceramic which does not impregnate a liquid, an adhesive, etc., has a negative coefficient of thermal expansion, can be stably produced at a low cost in terms of composition and physical properties, and a temperature compensation member using the same. .

[0022]

Means for Solving the Problems The inventors of the present invention have conducted various test studies in order to achieve the above-mentioned object, and as a result, heat treated Li ₂ O--Al ₂ O ₃ --SiO ₂ type glass having a specific composition range. By precipitating fine crystal particles, we succeeded in improving the stability of the material, suppressing the generation of microcracks, and obtaining glass ceramics without anisotropy. The inventors have found that they are suitable and have completed the present invention.

That is, the invention according to claim 1 contains 4% by mass or more of P ₂ O ₅ , and the main crystal phase is β-eucryptite (β-Li ₂ O.Al ₂ O ₃ .2SiO). ₂ ), β-
Eucryptite solid solution (β-Li ₂ O ・ Al ₂ O ₃・ 2
SiO ₂ solid solution), β-quartz (β-SiO ₂ ) and β-
At least one selected from quartz solid solutions (β-SiO ₂ solid solutions) is a glass-ceramic, and the invention according to claim 2 is -40 ° C to +.
The thermal expansion coefficient in the temperature range of 80 ° C. is −5 × 10 ⁻⁷
-90 × 10 ⁻⁷ / K. 3.
The glass ceramics according to claim 3, wherein the invention according to claim 3 has a coefficient of thermal expansion of −5 × 10 ⁻⁷ to −80 × 10 ⁻⁷ / K in a temperature range of −40 ° C. to + 80 ° C. The glass ceramics according to claim 1 or 2, wherein the invention according to claim 4 is -40 ° C to + 80 ° C.
Coefficient of thermal expansion in the temperature range of −5 × 10 ⁻⁷ to −60
X 10 ^-7 / K, characterized in that
The glass ceramic according to any one of the above,
The invention according to claim 5 is the glass-ceramic according to any one of claims 1 to 4, wherein the Young's modulus is 20 GPa or more, and the invention according to claim 6 is Young. The glass ceramics according to any one of claims 1 to 5, wherein the ratio is 60 GPa or more, and the invention according to claim 7 is a thermosetting epoxy adhesive for optical communication members. -40 ℃ after adhesion
Change in thermal expansion coefficient in the temperature range of + 80 ° C is -5x
The glass-ceramic according to any one of claims 1 to 6, characterized in that it is 10 ⁻⁷ / K to + 5 × 10 ⁻⁷ / K, and the invention according to claim 8 is −40. ℃
Thermal expansion hysteresis is 2 in the temperature range of + 80 ° C
It is 0 ppm or less, It is glass ceramics as described in any one of Claim 1 to 7, Comprising: The invention of Claim 9 WHEREIN: The average particle diameter of a main crystal phase is less than 5 micrometers. The glass ceramic according to any one of claims 1 to 8, which is characterized in that:
The invention according to claim 1 is the glass-ceramic according to any one of claims 1 to 9, characterized in that the crystal phase does not contain Al ₂ TiO ₅ crystals, and the invention according to claim 11 is The glass-ceramic according to any one of claims 1 to 10, which is substantially free of PbO, Na ₂ O and K ₂ O, and the invention according to claim 12 is mass%. , SiO ₂ 40-70% Al ₂ O ₃ 10-42% Li ₂ O 1-13% B ₂ O ₃ 0-5% BaO 0-3% SrO 0-3% MgO 0-10% CaO 0-2% ZnO 0-10% P ₂ O _{5 More} than 4% and less than 10% ZrO ₂ 0-2% TiO ₂ 0-4% TiO ₂ + ZrO ₂ 0.5-5.5% HfO ₂ 0-3% As ₂ O characterized in that it contains a ₃ + Sb ₂ O _{3 0~2%} of each component Claims 1 1
1 is a glass-ceramic according to any one of claims 1 to 14, and the invention according to claim 13 is such that the raw glass is melted, molded, and slowly cooled, and then the first heat treatment is performed at 550 to 800 ° C. for 0.5 to 50 hours. And then 0.5 at 600-950 ° C.
The glass-ceramic according to any one of claims 1 to 12, which is obtained by performing a second heat treatment for up to 30 hours, and the invention according to claim 14 is the glass-ceramic according to any one of claims 1 to 13. A temperature compensating member comprising the glass ceramic according to any one of them.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION The negative thermal expansion glass-ceramics of the present invention will be described in detail below. In the present invention, the glass ceramics is a material obtained by precipitating a crystal phase in the glass phase by heat-treating the glass, and not only the material consisting of the glass phase and the crystal phase, but also the entire glass phase is crystallized. A material having a phase transition to a phase, that is, a material having a crystal amount (crystallinity) of 100% by mass is also included. In addition, the composition of all constituents is% by mass.
Is.

In the present specification, the main crystal phase means all the crystal phases having a relatively large precipitation ratio. That is, in the X-ray chart in X-ray diffraction (the vertical axis is the X-ray diffraction intensity, the horizontal axis is the diffraction angle), the X-ray diffraction intensity of the main peak (highest peak) of the crystal phase with the highest precipitation ratio is 1
When it is set to 00, all those having a ratio of X-ray diffraction intensities (hereinafter, referred to as X-ray intensity ratio) of main peaks (highest peaks in each crystal phase) of each precipitated crystal phase of 30 or more are referred to as main crystal phases. Here, the X-ray intensity ratio of crystals other than the main crystal phase is preferably less than 20, more preferably less than 10, and most preferably less than 5.

The main crystal phase of the negative thermal expansion glass ceramics of the present invention is β-eucryptite (β-Li ₂
O.Al ₂ O ₃ .2SiO ₂ ), β-eucryptite solid solution (β-Li ₂ O ・ Al ₂ O ₃ .2SiO ₂ solid solution), β
-Quartz (β-SiO ₂ ), β-quartz solid solution (β-SiO ₂
At least one selected from the group of solid solutions). Here, the solid solution refers to a crystal in which β-eucryptite or β-quartz is partially substituted with an element other than the element constituting the crystal, or atoms penetrate into the crystal. To tell.

These main crystal phases are important factors contributing to the coefficient of thermal expansion of the negative thermal expansion glass-ceramics of the present invention. By heat-treating the raw glass having a specific composition under predetermined conditions, in the glass phase having a positive coefficient of thermal expansion, the main crystal phase having a negative coefficient of thermal expansion is precipitated,
Alternatively, it becomes possible to control the thermal expansion coefficient of the glass ceramic as a whole within a desired negative numerical value range by causing all the glass phases to undergo a phase transition to a crystal phase including the main crystal phase.

The types of these main crystal phases and the crystallinity with respect to the whole glass ceramics are determined according to the content ratios of Li ₂ O, Al ₂ O ₃ and SiO ₂ within the specific composition range, and all of the crystallizing conditions described later. It is determined by the heat treatment temperature.

The average crystal grain size means the average value of the size of the crystal grains constituting the polycrystal. The measurement is performed by SEM observation. When the average crystal grain size is large, the surface state becomes rough, it is difficult to obtain a dense material, and microcracks are easily caused. Therefore, the particle size (average) is preferably less than 5 μm, more preferably less than 3 μm, and most preferably less than 2 μm.

In the present specification, the coefficient of thermal expansion (coeffici)
ent of thermal expansion is the average linear expansion coefficient (av
erage liner thermal expansion). For use as a temperature compensating member for various devices, the thermal expansion coefficient is preferably −5 × 10 ⁻⁷ to −90 × 10 ⁻⁷ / K, and −5 × 10 ⁻⁷ when used for optical communication related devices.
To −85 × 10 ⁻⁷ / K are preferable, and −5 × 10 ⁻⁷ to ^−8.
0 × 10 ⁻⁷ / K is more preferable. In particular, as a temperature compensating material for fiber grating devices, the coefficient of thermal expansion is -5 × 10 ⁻⁷ to −60 × so that the coefficient of thermal expansion does not change.
10 ⁻⁷ / K is preferable, and −5 × 10 ⁻⁷ to −40 × 10 ^−7.
/ K is more preferable, and -5 × 10 ^-7 to -30 × 10 ^-7 /
K is particularly preferred.

The Young's modulus of the glass-ceramic of the present invention is preferably 20 GPa or more, more preferably 40 GPa or more, and particularly preferably 60 GPa or more.

The glass-ceramics of the present invention have a coefficient of thermal expansion change of −5 × 10 5 even when an organic adhesive or water adheres thereto.
It is preferable ^-7 / ^K~ + 5 × small as 10 ^-7 / K. Specifically, the change in the thermal expansion coefficient after adhesion of the thermosetting epoxy adhesive for optical communication members is −5 × 10 ⁻⁷ / K to + 5 × 10 ^−7.
/ K is preferable, and -3 × 10 ^-7 / K to + 3 ×
More preferably, it is 10 ⁻⁷ / K.

Thermal expansion hysteresis is the measurement of the coefficient of thermal expansion from low temperature to high temperature and from high temperature to low temperature, and when a ΔL / L curve is drawn, the curve is the most distant between the temperature rise and the temperature decrease. It is the difference between the ΔL / L values at different temperatures (that is, the maximum value of the difference in the coefficient of thermal expansion during temperature increase and decrease at each temperature). When used as various temperature compensating members, the coefficient of thermal expansion during temperature rise and temperature decrease greatly,
In other words, the fact that the material shape changes when the temperature is raised or lowered does not allow temperature compensation. As a result of various studies on this thermal expansion hysteresis, it was found that it can be applied as a temperature compensating member by setting the thermal expansion hysteresis to 20 ppm or less. A more preferable thermal expansion hysteresis is 18 ppm or less, a more preferable range is 15 ppm or less, and a particularly preferable range is 13 ppm.
ppm or less, and most preferably 5 ppm or less.

SiO ₂ of the glass-ceramic of the present invention,
The Li ₂ O and Al ₂ O ₃ components are important components that are constituent elements of the main crystal phases β-eucryptite, β-eucryptite solid solution, β-quartz, and β-quartz solid solution.

The SiO ₂ component is the main component of the above-mentioned main crystal having a negative coefficient of thermal expansion, but if the amount is less than 40%, the desired main crystal phase will not be sufficiently precipitated, and 70% When it exceeds the above, melting and refining of the glass becomes difficult, and a crystal phase other than the desired main crystal phase precipitates. Therefore, the preferable range of the SiO ₂ component amount is 40 to 70%, and the more preferable range is 45 to 70%. 65%.

Al₂O₃Ingredient is less than 10% glass
Since it becomes difficult to melt the glass, the homogeneity of the raw glass decreases and
Further, it becomes difficult to generate a desired amount of the desired main crystal phase. on the other hand,
If it exceeds 42%, the melting point becomes too high and the glass melts.
Since refining becomes difficult, Al ₂O₃Desired range of ingredients
Is 10 to 42%, and a more preferable range is 15 to 42%.
40%, and the most preferred range is 18-35%.

If the Li ₂ O content is less than 1%, it will be difficult to melt the raw glass and the required amount of the desired main crystal phase cannot be obtained. Further, if it exceeds 13%, vitrification becomes difficult, and the strength of the glass ceramics after heat treatment decreases, so the preferable range is 1 to 13%,
The most preferable range is 3 to 10%.

The B ₂ O ₃ component can be optionally added for the purpose of improving the meltability of the raw glass, but it is a component forming the glass phase portion of the negative thermal expansion glass ceramics of the present invention, and its amount is 5%. When it exceeds, the production of a desired main crystal phase is hindered and the heat resistance of the glass ceramic is deteriorated.

[0039] BaO component, beta-Yuktobanian descriptor important component as a component of the tight solid solution _{(β-Li 2 O · Al} 2 O 3 · 2SiO 2 solid solution) and beta-quartz solid solution (β-SiO ₂ solid solution) However, if the amount of each of these components exceeds 3%, the coefficient of thermal expansion of glass increases, and the coefficient of thermal expansion of glass ceramics increases. Further, the addition of 0.5% or more prevents the platinum in the crucible from alloying with other metal elements in the raw glass at the time of melting the raw glass, and maintains the devitrification resistance of the raw glass. Because there is
If possible, the content is preferably 0.5% or more, more preferably 0.5 to 2.5%, and the most preferable range is 0.
5 to 2.0%.

[0040] SrO component also β- eucryptite solid solution _{(β-Li 2 O · Al} 2 O 3 · 2SiO 2 solid solution) and beta
-It is an important component that constitutes a quartz solid solution (β-SiO ₂ solid solution), but if the amount of each of these components exceeds 3%, the coefficient of thermal expansion of glass increases, and the coefficient of thermal expansion of glass ceramics increases. . However, since it has the effect of reducing the thermal expansion hysteresis by combining with other RO (metal oxide) components, it is preferably contained in an amount of 0.5% or more, more preferably 0.5 to
2.5%, and the most preferable range is 0.5 to 2.0%.

The MgO component has the effect of improving the melting and refining of the glass, but has the effect of increasing the coefficient of thermal expansion of the glass ceramics, so if it exceeds 10%, the stability of the glass will deteriorate. It is desirable that it is preferably up to 5%, more preferably 2% or less.

The CaO component has the effect of improving the melting and refining of the glass, but if it exceeds 2%, a sufficient negative thermal expansion coefficient cannot be obtained, so it is preferably up to 2%, more preferably 1.5%. The following is good.

The ZnO component has the effect of improving the melting and refining of the glass and the effect of making the thermal expansion coefficient of the glass ceramic negative, but if it exceeds 10%, the stability of the glass deteriorates. The preferred range is not more than 6%, more preferably 0.5 to 5%.

The P ₂ O ₅ component acts as a crystal nucleating agent,
And acts as a glass former. In order to prevent devitrification of the raw glass, it is preferably 4% or more, more preferably more than 4%. On the other hand, if it exceeds 10%, melting and refining of the raw glass becomes difficult and unmelted matter may be generated, so less than 10 is preferable, 9% or less is more preferable, and 8
% Or less is particularly preferable.

Each of the components ZrO ₂ and TiO ₂ acts as a crystal nucleating agent. However, if the amount of each of these components exceeds 2% and 3%, it is difficult to melt and clarify the raw glass. Unmelted material may be generated. still,
The preferred range of ZrO ₂ is 0 to 2.0%, the most preferred range is 1.0 to 1.5%, the preferred range of TiO ₂ is 0 to 4.0%, the most preferred range is 0.5 to 2%. .5
%. Further, if TiO ₂ + ZrO ₂ exceeds 5.5%, it becomes difficult to obtain a desired thermal expansion coefficient, so it is desirable to set it to 5.5%.

The HfO ₂ component is a component that reduces the coefficient of thermal expansion of the raw glass, but if it exceeds 3%, the meltability deteriorates. The most preferable range is 2% or less.

The As ₂ O ₃ and Sb ₂ O ₃ components can be added as fining agents during glass melting in order to obtain a homogeneous product, but a total amount of these components of up to 2% is sufficient. . In addition to the above components, F ₂ , La ₂ O ₃ , and T may be added within a range that does not impair the desired properties of the glass ceramics of the present invention.
_{a 2 O 5, GeO 2,} Bi 2 O 3, WO 3, Y 2 O 3, Gd
₂ O ₃ , SnO ₂ , CoO, NiO, MnO ₂ , Fe ₂ O ₃ ,
Cr ₂ O ₃ , Nb ₂ O ₅ , V ₂ O ₅ , Yb ₂ O ₃ , CeO ₂ , C
s ₂ O etc. can be added up to 3% each.

The PbO component is an environmentally unfavorable component, and the Na ₂ O and K ₂ O components are diffused by these ions in the subsequent steps such as film formation and cleaning, so that the negative ions of the present invention. Since the physical properties of the heat-expandable glass ceramics are changed, it is preferable that the PbO, Na ₂ O and K ₂ O components are not substantially contained.

The glass ceramics of the present invention having the above composition is manufactured by the following method. First, glass raw materials such as oxides, carbonates, hydroxides, and nitrates are weighed and mixed so as to have the above-described composition, put into a crucible, etc.
Melt with stirring at 300 to 1550 ° C. for about 6 to 8 hours to obtain a raw glass in a clear state. Next, crystallization is performed by the following method.

As described above, after melting the raw glass, it is cast in a mold or the like to be molded and gradually cooled.

Next, heat treatment is performed. First, 550-80
Hold at a temperature of 0 ° C. to promote nucleation (first heat treatment).
This nucleation temperature is below 550 ° C or even 80
Even if the temperature is higher than 0 ° C, it is difficult to generate a desired crystal nucleus. More preferably, it is 580-750 degreeC, and the most preferable range is 600.
~ 700 ° C. Further, the heat treatment time is preferably set to 0.5 to 50 hours in order to obtain desired characteristics, and more preferably 1 to 30 hours from the viewpoint of more preferable characteristics, productivity and cost.

After nucleation, crystallization is performed at a temperature of 600 to 950 ° C. (second heat treatment). This crystallization temperature is 600 ℃
If it is lower, it is difficult to grow a sufficient amount of main crystal phase, and it is 950 ° C
If the ratio is higher, the raw glass tends to be softened, deformed or remelted, which is not desirable. The preferred range is 600 to 900 ° C, and the most preferred range is 650 to 800 ° C. After crystallization, it is desirable to gradually cool at a rate of 50 ° C./h or less, more preferably 25 ° C./h or less.

The crystallization temperature is also preferably set to 0.5 to 30 hours, and more preferably 1 to 20 hours for the same reason as in the first heat treatment.

[0054]

EXAMPLES Examples of the negative thermal expansion glass ceramics of the present invention will be described below. The present invention is not limited to these examples.

[0055]

[Table 1]

[0056]

[Table 2]

Tables 1 and 2 show the glass ceramics of Example No. 1 of the present invention. 1-No. 6, the composition ratio, the melting temperature, the nucleation temperature, the nucleation time, the nucleus growth temperature,
The nuclear growth time, the coefficient of thermal expansion, the coefficient of thermal expansion after the epoxy adhesive was attached, the Young's modulus, the rigidity, the Poisson's ratio, and the bending strength were shown. Further, FIG. 1 shows the thermal expansion curves before and after the adhesion of the adhesive in Example 1.

The glass ceramics of Examples 1 to 6 were manufactured as follows. First, glass raw materials such as oxides, carbonates, hydroxides, and nitrates were weighed and prepared so as to have the compositions shown in Tables 1 and 2, put into a platinum crucible, and the glass raw materials were put into a platinum crucible using a normal melting apparatus. It melted and stirred at the melting temperature described in 2 for 6 to 8 hours.

Next, the melted raw glass was cast into a mold and molded, and then gradually cooled to obtain a glass molded body. Then, the glass molded body was put into a crystallization furnace as it was, heated and heated to form crystal nuclei at the nucleation temperature and the nucleation time shown in Tables 1 and 2. Subsequently, the mixture was heated and heated to crystallize at the nucleus growth temperature and the nucleus growth time also shown in Tables 1 and 2, and then gradually cooled at a rate of 50 ° C./h or less to obtain glass ceramics.

Processing such as cutting and polishing is performed to obtain a desired shape, and after the processing, the temperature is raised at a rate of about 150 ° C./h,
Incubate at 200-400 ℃ for about 3 hours, then 50 ℃ /
It was cooled at a cooling rate of h, preferably 5 to 10 ° C./h.

A sample having a diameter of 5 mm and a length of 20 mm was cut out from the glass ceramics of the respective examples obtained as described above, and a temperature of −40 ° C. to + 80 ° C. was measured by a TAS200 thermomechanical analyzer manufactured by Rigaku Corporation. The coefficient of thermal expansion and the hysteresis in the range were measured. Then, a commercially available thermosetting epoxy adhesive for optical communication members was adhered to the measured material, the temperature was raised at 100 ° C./h to heat cure at 100 ° C. for 1 h, and then gradually cooled to room temperature. The thermal expansion coefficient of this sample was measured again in the temperature range of −40 ° C. to + 80 ° C. by the TAS200 thermomechanical analyzer manufactured by Rigaku Corporation.

A comparative example will be described below. (Comparative example 1) As a comparison, SiO in mass%₂  50.3%, Al₂O₃
  36.7%, Li₂O 9.7%, TiO₂  3.3% raw material is weighed and blended
After that, melt at 1600 ° C. to obtain a glass molded body,
Crystallization was performed at 300 ° C for 4 hours, and the thermal expansion coefficient was -78.
× 10^-7A glass ceramic of / K was obtained. Also implemented
Similar to the example, the coefficient of thermal expansion after adhesion of the adhesive is 1.0 x 10 ^-7
Was / K. Figure 2 shows the thermal expansion curves before and after the adhesive is applied.
You

[0063]

As described above, the glass-ceramic of the present invention has a specific composition range of Li ₂ O-Al ₂ O ₃ -Si.
By heat-treating the O ₂ —TiO ₂ glass to crystallize it, the glass has a negative thermal expansion coefficient in the temperature range of −40 ° C. to + 80 ° C. and has water or an organic adhesive attached. Change in thermal expansion coefficient is -5 × 10 ^-7 to + 5 × 10 ^-7 / K
Is. Therefore, it is often used in the optical communication field,
In optical devices such as fiber Bragg gratings, connectors, optical fiber couplers, and optical waveguides,
A material having a positive coefficient of thermal expansion and an organic adhesive can be used in combination to provide temperature compensation to the device.

Further, in addition to being a material having thermal stability and not having anisotropy in terms of various characteristics, by precipitating fine crystal grains, generation of microcracks can be suppressed and Excellent in strength. Furthermore, the problems of cleaning and changes in the coefficient of thermal expansion due to fiber bonding, which have been problems so far, are eliminated, and the processability is excellent, so that it can be used for ferrules of connectors.

For example, in the case of forming a small hole of φ0.125 mm in a cylinder having a diameter (φ) of 1.25 mm and a length of 6.5 mm, it is very difficult by a general processing method. In the glass-ceramic of the present invention, first, it is ground into a semi-cylinder, the surface thereof is mirror-polished, and then a semi-circular or V-shaped groove having a depth of about 0.063 mm is formed in the center, and two of these are bonded together. If so, a desired fine hole can be obtained. At this time, if the end of the groove is deep (for example, 0.45 mm) and tapered so that it gradually becomes shallow, and the end of the small hole is processed into a trumpet shape, the fiber will be smooth. Can be inserted into.

In addition to the optical communication field, energy related fields,
It can be used as a temperature compensating member in bulk form in a wide range of applications such as information and communication fields and electronics fields.

Further, the glass ceramics of the present invention can be produced by melting the raw glass at a relatively low temperature as compared with the conventional one, and the heat treatment temperature for crystallization is low, so that it can be produced at a low cost. Moreover, since the composition does not contain unstable components and the composition ratio can be easily controlled, stable production can be achieved in terms of composition and physical properties.

[Brief description of drawings]

FIG. 1 is a thermal expansion curve of Example 1 before and after adhesion of an adhesive.

FIG. 2 is a thermal expansion curve of Comparative Example 1 before and after an adhesive is attached.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4G015 EA02                 4G062 AA11 BB06 BB09 CC04 DA05                       DA06 DB04 DB05 DC01 DC02                       DD03 DE01 DE02 DE03 DF01                       EA03 EA04 EB01 EC01 ED01                       ED02 ED03 EE01 EE02 EE03                       EF01 EF02 EF03 EG01 EG02                       EG03 FA01 FA10 FB01 FB02                       FB03 FC01 FC02 FC03 FD01                       FE01 FF01 FG01 FH01 FJ01                       FK01 FL01 GA01 GA10 GB01                       GC01 GD01 GE01 HH01 HH03                       HH05 HH07 HH09 HH11 HH13                       HH15 HH17 HH18 HH20 JJ01                       JJ03 JJ04 JJ05 JJ07 JJ10                       KK01 KK03 KK05 KK07 KK10                       MM04 NN01 NN30 NN33 QQ01                       QQ02 QQ09 QQ11

Claims (14)

[Claims] 1. A P ₂ O ₅ content of 4% by mass or more, wherein the main crystal phase is β-eucryptite (β-Li ₂ O.Al ₂ O ₃
・ 2SiO ₂ ), β-eucryptite solid solution (β-L
i ₂ O ・ Al ₂ O ₃・ 2SiO ₂ solid solution), β-quartz (β-
SiO ₂ ) and β-quartz solid solution (β-SiO ₂ solid solution)
At least one selected from the above is a glass-ceramic. 2. The glass-ceramic according to claim 1, which has a coefficient of thermal expansion of −5 × 10 ⁻⁷ to −90 × 10 ⁻⁷ / K in a temperature range of −40 ° C. to + 80 ° C. 3. The glass according to claim 1, which has a coefficient of thermal expansion of −5 × 10 ⁻⁷ to −80 × 10 ⁻⁷ / K in the temperature range of −40 ° C. to + 80 ° C. Ceramics. 4. The thermal expansion coefficient in the temperature range of −40 ° C. to + 80 ° C. is −5 × 10 ⁻⁷ to −60 × 10 ⁻⁷ / K, which is any one of claims 1 to 3. The glass-ceramics according to item 1. 5. The glass-ceramic according to claim 1, which has a Young's modulus of 20 GPa or more. 6. The glass-ceramic according to claim 1, which has a Young's modulus of 60 GPa or more. 7. A thermosetting epoxy adhesive for optical communication members.
Thermal expansion in the temperature range of -40 ℃ to + 80 ℃ after adhesion
Change in tension coefficient is -5 x 10^-7/ K ~ +5 x 10 ^-7/ K
One of claims 1 to 6, characterized in that
The glass-ceramics according to the item. 8. The glass-ceramic according to claim 1, which has a thermal expansion hysteresis of 20 ppm or less in a temperature range of −40 ° C. to + 80 ° C. 9. The glass-ceramic according to claim 1, wherein the main crystal phase has an average grain size of less than 5 μm. 10. The glass-ceramic according to any one of claims 1 to 9, wherein the crystal phase does not contain Al ₂ TiO ₅ crystals. 11. The glass-ceramic according to claim 1, which is substantially free of PbO, Na ₂ O and K ₂ O. 12. In mass%, SiO ₂ 40-70% Al ₂ O ₃ 10-42% Li ₂ O 1-13% B ₂ O ₃ 0-5% BaO 0-3% SrO 0-3% MgO 0 10% CaO 0-2% ZnO 0-10% P ₂ O _{5 More} than 4% and less than 10% ZrO ₂ 0-2% TiO ₂ 0-4% TiO ₂ + ZrO ₂ 0.5-5.5% HfO the _{2 0~3% as 2 O 3 +} Sb 2 O 3 0~2% of each component is characterized by containing from claim 1 1
1. The glass ceramic according to any one of 1. 13. The raw glass is melted, shaped and gradually cooled, and then 55
The first heat treatment is performed at 0 to 800 ° C. for 0.5 to 50 hours, and then the second heat treatment is performed at 600 to 950 ° C. for 0.5 to 30 hours. 12. The glass ceramics according to any one of 12. 14. A temperature compensating member comprising the glass-ceramic according to any one of claims 1 to 13.