JP6264054B2 - Laminated glass ceramic sintered body and method for producing laminated glass ceramic sintered body - Google Patents

Description

  The present invention relates to a laminated glass ceramic sintered body on which a pattern, a character, and the like are printed, and a technique for a method for producing the laminated glass ceramic sintered body.

In recent years, in the field of portable devices, user interfaces such as a touch pad attached to a notebook personal computer that allow a user to perform intuitive operations by directly touching with a fingertip are increasing.
As a constituent member of the touch pad, as disclosed in Patent Document 1, a substrate made of resin, glass, metal, or the like is often used conventionally.

JP2013-254522A

However, in the case of a touch pad made of a resin substrate, the wear of the surface proceeds due to friction with the fingertip when operating the touch pad, and it is difficult to maintain the flatness of the surface over a long period of time. . As a result, there is a problem that the fingertip is less likely to slip with respect to the touch pad, and the operability of the touch pad is likely to deteriorate.
For this reason, in the field of portable devices, for example, the wear resistance is improved so that the flatness can be maintained over a long period of time at a site where friction with a fingertip such as a touch pad surface occurs. It was required to plan.

On the other hand, for touchpads, it has traditionally been considered to apply patterns and characters on the surface for the purpose of improving design and transmitting product information. However, it has not been realized for the following reasons. It has not reached.
In other words, even if a pattern or character is applied on the surface of the touchpad, the pattern or character may be peeled off due to friction with the fingertip during touchpad operation, or may be caused by the touch of the fingertip during touchpad operation. For example, the user may feel a step on the boundary line of characters and characters, causing discomfort in the operation of the touch pad.
For this reason, in the field of mobile devices, for example, a part that causes friction with the fingertip, such as the surface of a touch pad, may be peeled off due to friction with the fingertip during operation, or the touch of the fingertip during operation Therefore, it has been demanded to improve the design properties by using patterns and characters that do not cause discomfort.

In the field of portable devices, members that can damage the symbols and characters applied on the surface due to friction with the fingertips and palms are members of the operation unit such as a touchpad. It is not limited.
For example, in a portable device such as a mobile phone or a portable game machine, when operating the portable device, a casing that is an exterior is gripped, and therefore, images and characters constructed on the surface of the casing are It was often damaged by friction with fingertips and palms.
For parts such as the exterior gripped by palms and fingertips, the design and characters are improved by design and text, etc., and will not peel off due to friction with palms or fingertips after long-term use. There has been a need to improve wear.

  Furthermore, in electrical appliances, in recent years, design (designability) is often given priority in addition to function, and there is a demand for the development of members that can be easily designed in various ways and their manufacturing methods. It was done.

  The present invention has been made in view of the present problems described above. For example, in a region where friction with a fingertip or a palm occurs, such as a touch pad or a surface of an exterior in the field of portable devices. To provide a laminated glass ceramic sintered body capable of realizing excellent wear resistance and maintaining designability for a long period of time when used, and a method for producing the laminated glass ceramic sintered body Let it be an issue.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, the laminated glass ceramic sintered body according to claim 1 of the present invention includes a first glass ceramic sintered body layer, a second glass ceramic sintered body layer, the first glass ceramic sintered body layer, and a second glass ceramic sintered body layer. becomes the arranged pattern layer between the glass ceramic sintered body layer is laminated integrally, wherein the first glass ceramic sintered body layer is transmitted through the visible light, the first glass ceramics sintered body The layer contains 30 to 70% glass and 70 to 30% ceramic by mass percentage, and the ceramic is one or more kinds of ceramics selected from the group consisting of alumina, mullite, zircon, zirconia, and cordierite, a layer, Ri name and picture and / or characters are formed, the pattern layer is, in the depth direction from the surface of the first glass ceramic sintered body layer 20 [[mu] m] Beyond being formed and 400 [[mu] m] following positions, bending strength measured by the three-point bending test, and 200 [MPa] or more der wherein Rukoto.

  The laminated glass ceramic sintered body according to claim 2 of the present invention is characterized in that the second glass ceramic sintered body layer has a visible light transmittance lower than that of the first glass ceramic sintered body layer. .

  The laminated glass-ceramic sintered body according to claim 3 of the present invention is characterized in that at least one surface has a step, and the step is 20 [μm] or less.

In the laminated glass-ceramic sintered body according to claim 4 of the present invention, the picture layer is made of glass and an inorganic pigment, and is in a mass percentage of 70 to 99.8% for glass and 0.2 to 30% for inorganic pigment. It is characterized by being.

The laminated glass-ceramic sintered body according to claim 5 of the present invention is characterized in that the first glass-ceramic sintered body layer does not contain an inorganic pigment.

The laminated glass ceramic sintered body according to claim 6 of the present invention is characterized in that the picture layer is visible from at least one surface.

The laminated glass ceramic sintered body according to claim 7 of the present invention is used as an exterior of a portable electronic device.

The laminated glass ceramic sintered body according to claim 8 of the present invention is used as a touch pad of a notebook computer.

The method of manufacturing laminated glass ceramics sintered body according to claim 9 of the present invention, a pattern portion comprising a pattern layer to form a pattern and / or text on the second green sheet surface containing glass powder and ceramics powder was formed by coating a slurry of the pattern material, the second green sheets were arranged該絵shank, so as to sandwich the picture section, laminating the first green sheet containing a glass powder and ceramics powder It is characterized by comprising a laminating step, a crimping step of crimping a green sheet laminate obtained by laminating in the laminating direction, and a sintering step of sintering the crimped green sheet laminate.

In the method for producing a laminated glass-ceramic sintered body according to claim 10 of the present invention, the thickness of the first green sheet laminated on the pattern portion of the second green sheet on which the pattern portion is arranged is 50 [μm]. And 600 [μm] or less.

In the method for producing a laminated glass-ceramic sintered body according to claim 11 of the present invention, the pattern part is made of a material containing glass powder and inorganic pigment powder, and the glass powder: inorganic pigment powder is 70 to 70 by mass ratio. 99.8: 0.2-30.

The laminated glass ceramic sintered body manufacturing method according to claim 12 of the present invention is characterized in that the first green sheet does not contain inorganic pigment powder.

The method for producing a laminated glass-ceramic sintered body according to claim 13 of the present invention is characterized in that the pattern portion is formed by screen printing.

In the method for producing a laminated glass-ceramic sintered body according to claim 14 of the present invention, the pattern portion is between an outermost green sheet in the green sheet laminate and a green sheet adjacent to the outermost green sheet. It is characterized by being arranged in.

  As effects of the present invention, the following effects can be obtained.

According to the laminated glass-ceramic sintered body according to claim 1 of the present invention, since the surface thereof is composed of the first glass-ceramic sintered body layer, excellent wear resistance can be realized.
Moreover, the pattern layer is visible through the first glass ceramic sintered body layer and is not directly touched from the outside. Therefore, for example, the design layer does not peel off due to friction with a fingertip or the like, and the design can be maintained over a long period of time.
Moreover, according to the laminated glass ceramic sintered body according to claim 1 of the present invention, the pattern layer exceeds 20 [μm] in the depth direction from the surface of the first glass ceramic sintered body layer, and 400 [μm]. ] Since it is formed in the following positions, it is possible to ensure better visibility from the surface of the pattern layer.
Furthermore, according to the laminated glass-ceramic sintered body according to claim 1 of the present invention, the bending strength measured by the three-point bending test is 200 [MPa] or more. ensuring the rigidity to withstand the impact or the like from the possible.

  According to the laminated glass-ceramic sintered body according to claim 2 of the present invention, it is possible to ensure good visibility from the surface of the pattern layer.

  According to the laminated glass-ceramic sintered body according to claim 3 of the present invention, even if it is used for a user interface operated by stroking with a fingertip, such as a touch pad of a notebook computer, it exists on the surface. The touchpad can be operated without worrying about the level difference.

According to the laminated glass-ceramic sintered body according to claim 4 of the present invention, since the ratio of the glass contained in the pattern layer is large, the thermal expansion coefficient of the pattern layer is set to the thermal expansion coefficient of the glass-ceramic sintered body layer. And approximately the same.
Therefore, it is possible to prevent the interface or the like between the pattern layer and the glass ceramics sintered body layer such as cracks and breakage may occur.

According to the laminated glass-ceramic sintered body according to claim 5 of the present invention, it is possible to secure a better visibility from the surface of the pattern layer.

According to the laminated glass-ceramic sintered body according to claim 6 of the present invention, it is possible to sufficiently improve the designability and transmit product information.

According to the laminated glass ceramic sintered body according to claim 7 of the present invention, it is possible to provide an exterior of a portable electronic device capable of imparting excellent wear resistance and designability over a long period of time. .

According to the laminated glass-ceramic sintered body according to claim 8 of the present invention, it is possible to provide a touch pad for a notebook computer capable of imparting excellent wear resistance and designability over a long period of time. .

According to the method for producing a laminated glass-ceramic sintered body according to claim 9 of the present invention, since the surface is formed from the glass-ceramic sintered body layer, the laminated glass-ceramic sintered body having excellent wear resistance is obtained. Can be obtained.
Moreover, in the laminated glass ceramic sintered body obtained, the pattern layer is visible through the first glass ceramic sintered body layer and is not directly touched from the outside. Therefore, according to the production method of the present invention, for example, these picture layers are not peeled off due to friction with a fingertip or the like, and the laminated glass ceramic sintered body that can maintain the design property for a long period of time. You can get a body.

According to the method for producing a laminated glass-ceramic sintered body according to claim 10 of the present invention, in the obtained laminated glass-ceramic sintered body, it is possible to ensure better visibility from the surface with respect to the pattern layer. it can.

According to the method for producing a laminated glass-ceramic sintered body according to claim 11 of the present invention, since the ratio of the glass powder contained in the pattern portion is large, the coefficient of thermal expansion of the sintered pattern layer is determined by the glass ceramic firing. The coefficient of thermal expansion of the combined layer can be approximately the same.
Therefore, for example, during sintering, it is possible to prevent cracks or breakage from occurring at the interface between the pattern layer and the glass ceramic due to the difference in thermal expansion coefficient between the glass ceramic sintered body layer and the pattern layer. it can.

According to the method for producing a laminated glass-ceramic sintered body according to claim 12 of the present invention, in the obtained laminated glass-ceramic sintered body, it is possible to ensure better visibility from the surface with respect to the pattern layer. it can.

According to the method for producing a laminated glass-ceramic sintered body according to claim 13 of the present invention, in the obtained laminated glass-ceramic sintered body, a pattern portion is formed on the green sheet continuously and in large quantities by general screen printing. Since printing can be performed, manufacturing costs can be reduced.

According to the method for producing a laminated glass-ceramic sintered body according to claim 14 of the present invention, in the obtained laminated glass-ceramic sintered body, the pattern layer is surely disposed between the adjacent glass-ceramic sintered bodies. Meanwhile, good visibility from the outside can be secured.

Side surface sectional drawing which showed the laminated glass ceramic sintered compact concerning one Embodiment of this invention. It is the figure which showed each process at the time of forming a laminated glass ceramic sintered compact, (a) is side sectional drawing which showed the state of the green sheet in a lamination process, (b) is the state of the green sheet in a crimping process. The side sectional view shown, (c) is a side sectional view showing a state of the laminated glass ceramic sintered body sintered in the sintering step.

  Next, embodiments of the invention will be described.

[Laminated glass ceramic sintered body 1]
First, the structure of the laminated glass ceramic sintered body 1 that embodies the present invention will be described with reference to FIG.
In the following description, for convenience, the vertical direction of FIG. 1 is described as the vertical direction of the laminated glass ceramic sintered body 1.

The laminated glass-ceramic sintered body 1 of the present embodiment includes a plurality of glass-ceramic sintered body layers 11, 11... And a picture layer 12 that expresses a picture and / or a character. The pattern layer 12 is formed inside the glass ceramic sintered body 1.
Specifically, for example, the pattern layer 12 is a glass-ceramic sintered body layer located in one of the outermost layers of the laminated glass-ceramic sintered body 1 (upward in the present embodiment) of the laminated glass-ceramic sintered body 1. 11 (hereinafter referred to as “first glass ceramic sintered body layer 11A” as appropriate) and a glass ceramic sintered body layer 11 adjacent to the first glass ceramic sintered body layer 11A (hereinafter referred to as “first And a portion corresponding to “a two-glass ceramics sintered body layer 11 </ b> B”).
Incidentally, the second glass ceramics sintered body layer 11B may be formed even with, or be a laminate of a plurality of glass ceramic sintered body layer 11.

The first glass-ceramic sintered body layer 11 </ b> A has translucency, and the pattern layer 12 disposed inside the laminated glass-ceramic sintered body 1 is visually recognized from the surface of the laminated glass-ceramic sintered body 1. be able to.
In particular, when the picture layer 12 is visually recognized from one (upper) surface of the laminated glass ceramics sintered body 1, a single layer of translucency is provided between the surface of the laminated glass ceramics sintered body 1 and the picture layer 12. Since only the first glass ceramic sintered body layer 11 </ b> A is present, for example, laminated glass in which four glass ceramic sintered body layers 11, 11, 11, and 11 exist between the pattern layer 12. Compared with the case of visually recognizing from the other surface (downward in the present embodiment) of the ceramic sintered body 1, it can be visually recognized well.
Here, 11 A of 1st glass ceramic sintered compact layers are hard to impair translucency by not containing an inorganic pigment.

The visible light transmittance of the second glass ceramic sintered body layer 11B is not particularly limited, but may be lower than the visible light transmittance of the first glass ceramic sintered body layer 11A.
Moreover, when the pattern layer 12 consists of the colored pattern layer 12, it is preferable that the 2nd glass ceramic sintered compact layer 11B consists of a layer of a color different from the white layer or the pattern layer 12. FIG.
Moreover, when the pattern layer 12 consists of a white pattern layer 12, it is preferable that the 2nd glass ceramic sintered compact layer 11B consists of a colored layer.
Here, when the second glass ceramics sintered body layer 11B contains an inorganic pigment, it is excellent in concealing property. Therefore, even if the second glass ceramics sintered body layer 11B is made opaque, the laminated glass ceramics The sintered body 1 can be thinned, and weight reduction of an electronic device using the same can be achieved.
Moreover, the outline part of the pattern layer 12 becomes clear and the pattern layer 12 can be visually recognized more clearly from the surface of the glass ceramic sintered body layer 11A.

Thus, although the pattern layer 12 is visible from the surface of the laminated glass ceramic sintered body 1, it is not directly touched from the outside.
Therefore, for example, the design layer 12 can be maintained for a long period of time without peeling off the pattern layer 12 due to friction with a fingertip or the like.

  The degree of visibility of the pattern layer 12 is the thickness of the glass ceramic sintered body layer 11 formed on the pattern layer 12, that is, the distance from the surface of the laminated glass ceramic sintered body 1 to the pattern layer 12 ( It is influenced by the dimension T) in FIG.

That is, when the distance from the surface of the laminated glass ceramic sintered body 1 to the pattern layer 12 becomes too large, the visibility of the pattern layer 12 tends to decrease.
On the other hand, when the distance from the surface of the laminated glass ceramic sintered body 1 to the pattern layer 12 becomes too small, the pattern layer 12 is easily peeled off due to friction with the palm and the fingertip.

For this reason, in order to ensure good visibility of the pattern layer 12, the pattern layer 12 is deep from at least one surface (in this embodiment, the outer surface of the first glass ceramic sintered body layer 11A). In the vertical direction, it is preferably formed at a position exceeding 20 [μm] and not more than 400 [μm] (20 [μm] <T ≦ 400 [μm]).
More specifically, in the depth direction from the outer surface of the first glass ceramic sintered body layer 11A, it exceeds 20 [μm] and is 200 [μm] or less (20 [μm] <T ≦ 200 [μm]). It is more preferable to form the pattern layer 12 at the position.

Further, in the laminated glass ceramic sintered body 1 of the present embodiment, on one surface (the upper surface in the present embodiment), a protrusion 11a is formed by raising a portion corresponding to a portion where a pattern 12 is formed. Has been.
That is, the thickness of the picture layer 12 affects the surface shape of the laminated glass ceramic sintered body 1, and a protrusion 11a corresponding to the thickness of the picture layer 12 is formed at a location corresponding to the part where the picture layer 12 is formed. Has been.

  On the surface of the laminated glass ceramic sintered body 1, if the protruding dimension of the protrusion 11a is large, it adversely affects the touch when the surface of the laminated glass ceramic sintered body 1 is boiled while touching the surface with a fingertip.

For this reason, in order to ensure a good feel when stroking while touching the surface with a fingertip, the step size between the portion where the protrusion 11a is formed and the portion where the protrusion 11a is not formed (FIG. 1). The dimension H) is preferably set to 20 [μm] or less (H ≦ 20 [μm]).
More specifically, it is more preferable to set the step size H to be 15 [μm] or less (H ≦ 15 [μm]).
And this level | step difference dimension (H) can be adjusted easily by forming so that the thickness of the pattern part 21 formed in the surface of the green sheet 20 mentioned later may become 20 [micrometers] or less after baking.

In the present embodiment, the pattern layer 12 has been disposed between the first glass ceramics sintered body layer 11A and the second glass ceramics sintered layer 11B, is not limited to this, it is also possible to arrange between the other glass ceramics sintered body layers 11, 11.
However, even in this case, the distance (T) from the surface of the laminated glass ceramic sintered body 1 to the pattern layer 12, and the step size (H) between the portion where the protrusion 11a is formed and the portion where the protrusion 11a is not formed. ) Is preferably within the above range.

In addition, the laminated glass ceramic sintered body 1 of the present embodiment has a high strength because the plurality of glass ceramic sintered body layers 11, 11... And the pattern layer 12 are laminated and integrated. it can.
Specifically, the bending strength measured by a three-point bending test can be 200 [MPa] or more.

  Furthermore, as described above, the laminated glass ceramic sintered body 1 of the present embodiment has high strength without the image layer 12 being peeled off by friction with a fingertip or the like. Design in addition to wear resistance, such as components and exteriors of portable electronic devices, instead of conventional resin substrates, in parts that require wear resistance, such as the attached touchpad It can be used as a constituent member of a part that requires the property.

The glass ceramic sintered body layer 11 described above, includes a glass and ceramics, the content of glass and ceramics may be appropriately adjusted depending on the thickness of the glass and ceramics of the type and the glass ceramic sintered body , in percent by mass, the glass 30% to 70%, it is preferable to adjust the ceramics so that 30% to 70%.

Incidentally, the glass constituting the glass ceramic sintered body layer 11, at least, silicon dioxide (SiO _2), boron oxide (B ₂ O _3), and made of glass containing alkaline earth metal oxide.

Silicon dioxide (SiO ₂ ) is a glass network former, and its content is 40% to 60% by mass percentage.
When the content of silicon dioxide (SiO ₂ ) is less than 40%, the softening point becomes too low, the sintering start temperature becomes low, and sintering starts before the binder component scatters. It cannot be obtained. Further, when the sintered body is reheated, the sintered body is easily deformed.
On the other hand, when the content of silicon dioxide (SiO ₂ ) is more than 60%, the softening point becomes too high and it becomes difficult to sinter at a temperature of 1000 ° C. or lower.

Boron oxide (B ₂ O ₃ ) is a component that facilitates vitrification, and its content is 20% to 40% by mass percentage.
When the content of boron oxide (B ₂ O ₃ ) is less than 20%, vitrification becomes difficult and a dense sintered body cannot be obtained at a temperature of 1000 ° C. or lower.
On the other hand, if the amount of boron oxide (B ₂ O ₃ ) exceeds 40%, the water resistance decreases.

Alkaline earth metal oxides of magnesium oxide (MgO), calcium oxide (CaO), strontium oxide (SrO) and barium oxide (BaO) are components that improve the meltability of glass, and their content is expressed as a percentage by mass. 5% to 20%.
When the alkaline earth metal oxide is less than 5%, the meltability is deteriorated.
On the other hand, if the amount of alkaline earth metal oxide exceeds 20%, the thermal expansion diameter number becomes too large.

In addition, the glass component in this embodiment is an example, and is not limited thereto. For example, other components such as aluminum oxide (Al ₂ O ₃ ) and zirconium dioxide (ZrO ₂ ) are further included. It may be constituted by completely different components.

The ceramics constituting the glass ceramic sintered layer 11, for example, alumina, mullite, zircon, zirconia, is selected from the group including cordierite, it may be used ceramics of one or more kinds.

The pattern layer 12 formed inside the laminated glass ceramic sintered body 1 includes glass and an inorganic pigment, and the content ratio of the glass and the inorganic pigment may be appropriately adjusted depending on the kind of the glass or the inorganic pigment. It is preferable to adjust the percentage within a range of 70 to 99.8% for glass and 0.2 to 30% for inorganic pigment.
In addition, what is necessary is just to increase the content rate of an inorganic pigment, in order to improve the visibility of the pattern layer 12. FIG.

As glass which comprises the pattern layer 12, the same glass as the glass which comprises the glass ceramic sintered compact layer 11 mentioned above can be used.
By making the glass constituting the pattern layer 12 and the glass constituting the glass ceramic sintered body layer 11 the same, the thermal expansion coefficients of the pattern layer 12 and the glass ceramic sintered body layer 11 can be easily approximated. Therefore, peeling at the interface between the pattern layer 12 and the glass ceramic sintered body layer 11 hardly occurs, and the laminated glass ceramic sintered body 1 having a small warpage can be obtained.

The inorganic pigment constituting the pattern layer 12 is a blue pigment such as Co—Cr—Al, Fe—Mn, Co—Si, and Co—Al, Co—Si—Al, Ni—Mn—Fe—Co. Type, Co-Cr-Fe type, Cu-Cr-Mn type, Co-Cr-Ni type black pigment, Fe-Cr-Zn type brown pigment, Ti-Sb-Cr type red yellow pigment, From one or more inorganic pigments selected from the group of yellow pigments such as Ti—Sb—Ni, blue-green pigments such as Co—Al—Cr, and white pigments such as TiO ₂ , ZrO ₂ , Al ₂ O ₃ Become.
Moreover, these inorganic pigments can be contained in the second glass ceramic sintered body layer 11B as necessary.

[Method for Manufacturing Laminated Glass Ceramics Sintered Body 1]
Next, the manufacturing method of the laminated glass ceramic sintered body 1 is demonstrated using FIG.
In the following description, for convenience, the vertical direction of FIG. 2 is described as the vertical direction of the laminated glass ceramic sintered body 1.

First, the green sheet 20 to be the glass ceramic sintered body layer 11 is produced.
Specifically, a ceramics powder of the glass powder and the above-mentioned ceramics comprising glass described above, were mixed at a predetermined mixing ratio, further binder, by mixing by adding a plasticizer, and a solvent or the like, A slurry-like glass ceramic material is prepared.
The mass ratio of the glass powder and the ceramics powder, glass powder: ceramics powder 30-70: is preferably adjusted so that 30 to 70.

In addition, as a binder, ethyl cellulose resin, polyvinyl butyral resin, methacrylic acid resin, etc. can be used, for example.
Moreover, as a plasticizer, dibutyl phthalate etc. can be used, for example.
Further, as the solvent, for example, terpineol, butanol, toluene, methyl ethyl ketone and the like can be used.

Then, the prepared slurry-like glass ceramic material is continuously applied on a belt-like polyester film by a doctor blade method, dried, cut into predetermined dimensions, and formed into a plurality of single-wafer shapes.
In this way, a plurality of green sheets 20, 20.

Next, the pattern part 21 is formed on the surface of the produced green sheet 20.
Specifically, the glass powder that becomes the glass and the inorganic pigment powder that becomes the inorganic pigment described above are mixed at a predetermined mixing ratio, and further, a binder, a plasticizer, a solvent, and the like are added and mixed. A slurry-like pattern material is prepared.
The mass ratio of the glass powder to the inorganic pigment powder is preferably adjusted so that the glass powder: inorganic pigment powder is 70 to 99.8: 0.2 to 30.
Note that the same glass powder, binder, plasticizer, solvent, and the like as those used in producing the above-described green sheet can be used.

  Thereafter, a slurry-like pattern material is applied to the surface of the green sheet 20 produced as described above and dried to form the pattern portion 21 on the surface of the green sheet 20.

  In addition, as a method of forming the pattern part 21, it is preferable to use a screen printing method capable of printing the pattern part 21 continuously and in large quantities on the surface of the green sheet 20 and suppressing the manufacturing cost.

And the laminated glass ceramic sintered compact 1 is formed using the some green sheet 20 * 20 ... obtained by the above procedure.
Specifically, as shown in FIG. 2A, a predetermined number (for example, three in the present embodiment) of green sheets 20, 20, and 20 are laminated, and the green sheets 20, 20, and 20 are stacked. On the upper surface, a green sheet 20 (hereinafter referred to as “second green sheet 20B” as appropriate) on which the pattern portion 21 is formed by screen printing is laminated in a posture where the printing surface is the upper surface, and further the second green sheet 20B. A green sheet 20 positioned in the outermost layer (hereinafter referred to as “first green sheet 20 </ b> A” as appropriate) is laminated on the upper surface.
Thus, the lamination process which comprises a green sheet laminated body by laminating | stacking the five green sheets 20 * 20 ... first is performed.

In the laminated glass-ceramic sintered body 1 obtained after sintering, the pattern layer 12 formed inside the laminated glass-ceramic sintered body 1 is visible from one surface of the laminated glass-ceramic sintered body 1. For this purpose, the thickness dimension (dimension t in FIG. 2) of the green sheet 20 (first green sheet 20A in the present embodiment) laminated on the upper surface of the pattern portion 21 exceeds 50 [μm] and 600 [μm]. ] (50 [μm] <t ≦ 600 [μm]) is preferably adjusted below.
More specifically, the thickness dimension (t) of the first green sheet 20A is adjusted to exceed 50 [μm] and not more than 500 [μm] (50 [μm] <t ≦ 500 [μm]). Is more preferable.

  In this way, the distance from the surface of the laminated glass-ceramic sintered body 1 to the pattern layer 12 (dimension T in FIG. 1) is adjusted to be more than 20 [μm] and not more than 400 [μm]. It becomes possible to do.

  Further, in order to reduce the step size (the dimension H in FIG. 1) of the protrusion 11a formed on the surface of the laminated glass ceramic sintered body 1, the thickness dimension (see FIG. 1) formed on the surface of the green sheet 20 is reduced. It is preferable to adjust the dimension h1) in 2 (a) to be 30 to 40 [μm].

  By doing in this way, at the time of sintering, the pattern part 21 shrinks in the thickness direction, and the thickness dimension of the pattern layer 12 (dimension h2 in FIG. 2C) can be reduced to about 20 [μm] or less. It becomes easy to adjust the step size H of the protrusion 11a on the surface of the laminated glass ceramic sintered body 1 to 20 [μm] or less (H ≦ 20 [μm]).

In the present embodiment, the pattern portion 21 is disposed between the first green sheet 20A and the second green sheet 20B, but is not limited thereto, and is disposed between the other green sheets 20 and 20. It is also possible to do.
However, even in this case, the thickness dimension (t) of the green sheet 20 laminated on the upper surface of the pattern part 21 and the thickness dimension (h1) of the pattern part 21 formed on the surface of the green sheet 20 are within the above-mentioned ranges. Is preferred.

  Next, as shown in FIG. 2 (b), after the five green sheets 20 are laminated, a crimping step for obtaining a green sheet laminate is performed by crimping in a laminating direction with a jig or the like (not shown). .

Furthermore, the sintering process which sinters the said green sheet laminated body in a crimped state is performed.
That is, as shown in FIG. 2 (b), by heating the green sheet laminate in a pressure-bonded state in the atmosphere at a rate of 1 [° C.] per minute and holding at 500 [° C.] for 2 hours. Then, organic substances such as a binder and a plasticizer in each green sheet 20 are removed.

  Thereafter, the green sheet laminate is heated at a rate of 1 [° C.] per minute from 900 [° C.] to 1000 [° C.] and held for 1 hour to sinter the laminated glass ceramic shown in FIG. A sintered body 1 is obtained.

[Verification experiment]
Next, in the laminated glass-ceramic sintered body 1 in the present embodiment, the thickness dimension of the first glass-ceramic sintered body layer 11A located in the outermost layer (that is, the inside of the laminated glass-ceramic sintered body 1 described above). Appropriate ranges are set for the dimension from the pattern layer 12 to the surface of the laminated glass ceramic sintered body 1) T [μm] and the step dimension H [μm] of the protrusion 11a on the surface of the laminated glass ceramic sintered body 1. Therefore, a verification experiment conducted by the inventor will be described.

This inventor prepared the glass ceramic material and pattern material used as the material of a glass ceramic sintered compact according to the following procedures.
First, as a glass powder, 50% of silicon dioxide (SiO ₂ ), 30% of boron oxide (B ₂ O ₃ ), and alkaline earth metal oxides (MgO, CaO, SrO, and BaO) are contained in mass percentage. The glass raw material was prepared so that the amount) was 12%, aluminum oxide (Al ₂ O ₃ ) was 5%, and zirconium dioxide (ZrO ₂ ) was 3%. Then, this was put into a platinum crucible and 1400-1500 ° C. At a temperature of 3 to 6 hours.

  Next, the glass having an average particle diameter of 1.5 to 3.0 [μm] is obtained by stretching the melted glass into a thin plate shape with a water-cooling roller and then roughly crushing and wet-grinding while adding water with a ball mill. A powder was formed.

  Thereafter, a glass ceramic material and a pattern material were obtained using the glass powder thus formed.

The glass ceramic material was prepared using a glass powder and ceramics powder of the above.
Specifically, an alumina powder as a ceramics powder, as the mass ratio of the glass powder and the alumina powder is 50:50, was added to the alumina powder to the glass powder, the mixed powder obtained by mixing, A slurry-like glass ceramic material was prepared by adding and kneading ethyl cellulose as a binder, dibutyl phthalate as a plasticizer, and terpineol as a solvent.

Moreover, the pattern material was produced using said glass powder and inorganic pigment powder.
Specifically, a Co—Cr—Al blue pigment powder is used as the inorganic pigment powder, and the mass ratio of the glass powder to the Co—Cr—Al blue pigment powder is 99.5: 0.5. Inorganic pigment powder was added to glass powder and mixed to the resulting mixed powder. Polyvinyl butyral was used as a binder, dibutyl phthalate was used as a plasticizer, butanol was added as a solvent and kneaded to prepare a slurry-like pattern material. .

Then, this inventor formed the laminated glass ceramic sintered compact by the following procedures.
First, a plurality of green sheets having a thickness dimension of about 150 [μm] are formed by the doctor blade method using the produced slurry-like glass ceramic material, and the thickness dimensions are about 50 [μm] and about 100 [μm]. ], About 200 [μm], about 300 [μm], about 400 [μm], and about 580 [μm] green sheets were also formed.
For green sheets having a thickness of about 150 [μm], a predetermined number of green sheets on which pattern portions were formed were prepared by screen-printing the produced slurry-like pattern material.

Then, three green sheets with a thickness dimension of about 150 [μm] on which no pattern material is screen-printed are stacked, and then a green portion with a thickness dimension of about 150 [μm] is formed on the upper surface of the pattern portion (15 μm). The sheets are laminated with the pattern portion facing the upper surface, and the thickness is about 50 [μm], about 100 [μm], about 200 [μm], about 300 [μm], and about 400 [μm] on the upper surface. ], An uppermost green sheet of about 580 [μm] was laminated to produce green sheet laminates of Examples 1 to 6, respectively.
Further, as Comparative Example 1, a green sheet laminate in which the uppermost green sheet was not laminated was also produced.

  Then, the laminated glass ceramic sintered bodies of Examples 1 to 6 and Comparative Example 1 were formed by firing for 20 minutes at a temperature of 900 ° C. while pressing each green sheet laminate in the lamination direction.

  The plurality of laminated glass ceramic sintered bodies thus obtained were evaluated for the peelability of the pattern layer, the transmission state of the first glass ceramic sintered body layer, the surface step size, the feel of the surface step, and the bending strength. The evaluation result shown in the above was obtained.

In addition, about the peelability of a pattern layer, the following abrasion resistance test was evaluated.
That is, using a sandpaper of count # 3000, the surface of the laminated glass ceramic sintered body on the side on which the pattern layer was formed was reciprocated 1000 times at a load of 1.0 kg and a speed of 10 mm / sec. The presence or absence of was visually observed and evaluated.
The evaluation results are shown in Table 1 by “◯” when the pattern layer did not peel off and by “x” when the pattern layer was partially peeled off.

Moreover, about the permeation | transmission state of the 1st glass ceramic sintered compact layer, the laminated glass ceramic sintered compact was visually observed and evaluated from the side in which the pattern layer was formed.
The evaluation result is “◎” if the pattern layer can be clearly identified, “○” if it is not as clear as the case of “◎”, and “○” if the pattern layer can only be seen thin. Are identified in Table 1 by “Δ”.

As for the surface step size, the step size H of the contour portion of the pattern layer on the surface of the laminated glass-ceramic sintered body on the side where the pattern layer is formed (that is, the protrusion on the upper surface of the laminated glass-ceramic sintered body) (FIG. 1). Measured).
Specifically, using a micrometer, the thickness dimension of each laminated glass ceramic sintered body is divided into a part with a picture layer (dimension H2 in FIG. 1) and a part without a picture layer (dimension H1 in FIG. 1). The surface step size (H = H2−H1) was defined as the difference between these measured values.

In addition, regarding the feel of the surface step, the feel when the surface of the laminated glass ceramic sintered body on the side on which the pattern layer was formed was boiled while touching with a fingertip was evaluated.
The evaluation result is `` ○ '' if you can stroke with your fingertip without feeling a step, `` △ '' if you can stroke without feeling a hook when you stroke with your fingertip Table 1 shows that the existence of the step is clear and the step is caught by “x”.

  Regarding the bending strength P (unit [MPa]), each laminated glass-ceramic sintered body was processed into a rectangular shape of 40 [mm] × 10 [mm] in plan view, and then a sintered layer in which a pattern layer was formed. Each sample was arranged so that the body surface faced downward, and the bending strength was measured by a three-point bending test with a span of 30 [mm].

As shown in Table 1, about Examples 1-6, the distance T from the sintered compact surface which formed the pattern layer to the pattern layer is 30-360 [micrometers], and even if it carries out an abrasion resistance test, it is a pattern Even when the layer is not peeled off and used for an exterior of a portable electronic device or a touch pad of a notebook computer, it is expected that peeling of a pattern and / or characters due to friction with a palm or a fingertip can be prevented.
Further, the transmission state of the first glass ceramic sintered body layer was also able to identify the pattern layer.

  Furthermore, the surface level difference dimension H is 20 [μm] or less, and the surface level difference is not felt, or even if the level difference is felt, the surface is not caught when the fingertip is stroked.

  In addition, the bending strength is 270 [MPa] or more, and even when used for an exterior of a portable electronic device, a touch pad of a notebook computer, etc., it can withstand, for example, a drop or an unexpected external impact. It was possible.

  On the other hand, in Comparative Example 1, since the pattern layer is formed on the surface, the pattern layer peels off when the abrasion resistance test is performed, and the exterior of the portable electronic device, the touch pad of the notebook computer, etc. When it is used, it is expected that peeling of a pattern and / or characters due to friction with palms or fingertips cannot be prevented.

  Further, the surface step size H was 25 [μm], and the surface step feel was also caught when the surface of the sintered body was boiled while touching with the fingertip.

1 Laminated glass ceramic sintered body 1
DESCRIPTION OF SYMBOLS 11 Glass-ceramic sintered body layer 11A 1st glass-ceramic sintered body layer 11B 2nd glass-ceramic sintered body layer 11a Protrusion part 12 Picture layer 20 Green sheet 21 Picture part

Claims (14)

A first glass ceramic sintered body layer, a second glass ceramic sintered body layer, and a pattern layer disposed between the first glass ceramic sintered body layer and the second glass ceramic sintered body layer are laminated. Integrated,
Ri said first glass ceramics sintered body layer name and transmits visible light,
The first glass ceramic sintered body layer contains 30 to 70% glass and 70 to 30% ceramic by mass percentage,
The ceramic is one or more kinds of ceramics selected from the group of alumina, mullite, zircon, zirconia, cordierite,
By the pattern layer, Ri name and picture and / or characters are formed,
The pattern layer is formed at a position exceeding 20 [μm] in the depth direction from the surface of the first glass ceramic sintered body layer and not more than 400 [μm],
Bending strength measured by the three-point bending test, Ru der 200 [MPa] or more,
A laminated glass ceramic sintered body characterized by the above. The second glass ceramic sintered body layer has a lower visible light transmittance than the first glass ceramic sintered body layer,
The laminated glass ceramic sintered body according to claim 1, wherein At least one surface has a step,
The step is 20 [μm] or less,
The laminated glass ceramic sintered body according to claim 1, wherein the laminated glass ceramic sintered body is characterized. The pattern layer is made of glass and an inorganic pigment,
In terms of mass percentage, glass is 70 to 99.8%, inorganic pigment is 0.2 to 30%,
The laminated glass ceramic sintered body according to any one of claims 1 to 3 , wherein the sintered body is a laminated glass ceramic sintered body. The first glass ceramic sintered body layer does not contain an inorganic pigment,
The laminated glass ceramic sintered body according to any one of claims 1 to 4 , wherein the sintered body is a laminated glass ceramic sintered body. The pattern layer is visible from at least one surface;
The laminated glass ceramic sintered body according to any one of claims 1 to 5 , wherein the sintered body is a laminated glass ceramic sintered body. Used as the exterior of portable electronic devices,
The laminated glass ceramic sintered body according to any one of claims 1 to 6 , wherein the sintered body is a laminated glass ceramic sintered body. Used as a touchpad for notebook computers,
The laminated glass ceramic sintered body according to any one of claims 1 to 6 , wherein the sintered body is a laminated glass ceramic sintered body. A pattern portion comprising a pattern layer to form a second green sheet picture and / or text on the surface of which includes a glass powder and ceramics powder formed by coating a slurry of the pattern material, were placed該絵shank the second green sheet, so as to sandwich the pattern portion, and a laminating step of laminating the first green sheet containing a glass powder and ceramics powder,
A pressure-bonding step of pressure-bonding the green sheet laminate obtained by stacking in the stacking direction;
A sintering step of sintering the green sheet laminate that has been crimped,
A method for producing a laminated glass-ceramic sintered body. The thickness of the first green sheet laminated on the pattern portion of the second green sheet in which the pattern portion is arranged is more than 50 [μm] and not more than 600 [μm].
The method for producing a laminated glass-ceramic sintered body according to claim 9 , wherein: The pattern part is made of a material containing glass powder and inorganic pigment powder,
In a mass ratio, the glass powder: inorganic pigment powder is 70-99.8: 0.2-30,
The method for producing a laminated glass-ceramic sintered body according to claim 9 or 10 , wherein: The first green sheet does not contain inorganic pigment powder,
The method for producing a laminated glass-ceramic sintered body according to any one of claims 9 to 11 , wherein The pattern portion is formed by screen printing.
The method for producing a laminated glass-ceramic sintered body according to any one of claims 9 to 12 , characterized in that: The pattern portion is disposed between an outermost green sheet in the green sheet laminate and a green sheet adjacent to the outermost green sheet.
The method for producing a laminated glass-ceramic sintered body according to any one of claims 9 to 13 , wherein

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