JPH0238363A - Colored zirconia ceramic - Google Patents

Abstract

PURPOSE:To provide a colored zirconia ceramic having readily and finely controllable color tone, flexing resistance, toughness, etc., by blending a main component consisting of zirconia and stabilizer with a specific amount of CoO and Al2O3. CONSTITUTION:Zirconia powder is uniformly blended with stabilizer powder (e.g., Y2O3 powder). Then 100wt.% of the prepared main component is blended with 0.1-5wt.% pigment and 0.1-20wt.% Al2O3 as pigment to produce a colored zirconia ceramic. The colored zirconia ceramic colors in blue by CoO existing between particles of zirconia, added Al2O3 is reacted with part of CoO to form light blue CoO-Al2O3 and the color of the colored zirconia ceramic is lightened by the color of CoO-Al2O3. Consequently, color tone can be finely and readily controlled by regulating amounts of CoO and Al203 added.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to colored zirconia ceramics containing Coo in a zirconia base.

[Prior art]

Colored zirconia ceramics have been developed in recent years and are used for decorative parts such as watch cases, dials, and cufflinks.

Such colored zirconia ceramics were developed in Japanese Unexamined Patent Publication No. 1983
As shown in Publication No. 105055, it is obtained by adding a stabilizer and a pigment made of a metal oxide to zirconia. For example, if Coo is used as the pigment, blue colored zirconia ceramics can be obtained. .

[Issues with conventional technology]

When such colored zirconia ceramics are used as decorative members, it is necessary to delicately control the shade of color depending on the combination with other members. However, in conventional colored zirconia ceramics such as those mentioned above, in order to control the shade of color, Co, which is a pigment, is used.
It has been extremely difficult to delicately control the color tone since the only option is to change the o content.

[Means to solve the problem]

In view of the above, the present invention provides zirconia, Y2Off, Mg
100% by weight main component consisting of stabilizers such as O and CaO
On the other hand, colored zirconia ceramics are formed by containing 0.1 to 5% by weight of Coo as a pigment and 0.1 to 20% by weight of Al2O3 for color tone control.

The colored zirconia ceramics of the present invention develops a blue color due to Coo existing between zirconia particles, but some Coo reacts with the added Al2O:l, resulting in a pale blue color.
o0-Al□O1 is formed, and the blue color becomes lighter by this amount. If the amount of Al2O2 added is increased, the blue color becomes lighter, and if the amount added is reduced, the blue color becomes darker. Therefore, by controlling the amounts of Coo and Al2O3 added, subtle adjustments to the density can be made.

Further, the method for manufacturing the colored zirconia ceramics of the present invention is as follows. First, the zirconia raw material powder used has an average particle size of 0.15 μm or less, preferably 0.06 μm or less, and the stabilizer such as YzO3+MgO+CaO has an average particle size of 2 μm or less, preferably 1 μm or less. Alternatively, a coprecipitated zirconia powder to which a predetermined amount of a stabilizer has been added may be used. If this powder is used, the stabilizer and zirconia will be mixed in a more dense and uniformly distributed state, resulting in a sintered body. It has the advantage that the crystal grain size is made uniform.

Furthermore, the required amount of Co is added to the zirconia powder and the stabilizer.
o, Al□0. 1,200 to 1,700
If firing is performed in a vacuum furnace or an oxidation furnace at a temperature of preferably 1350 to 1550°C, a desired colored zirconia ceramic can be obtained.

〔Example〕

The present invention will be explained in detail below.

Example 1 3m of high purity zirconia powder as a stabilizer.

As shown in Table 1, various contents of Coo and Al2O are added to 100% by weight of the main components including Y2O,
2 was added thereto, 100% by weight of water was added thereto, the mixture was pulverized for 3 days in a vibration mill, and then dried. This was passed through 120 mesh, paraffin wax was added, and further passed through 80 mesh. This mixture was molded into a 7×7 molding pressure of 1 ton/cm”.
It was molded into a rod-shaped body measuring 65111 m x 65111 m and fired in an oxidizing atmosphere at a temperature of 1450 degrees.

The results of examining the flexural strength, toughness, and color tone of the colored zirconia ceramics thus obtained are the first.
It was as shown in the table.

The bending strength was measured according to the three-point bending test method of JIS-R-1601, and the toughness was measured using the critical stress intensity factor (K+c) when ceramics break due to the growth of microcracks as S, E, N, and Il. (Single Edge
e Notched beam) method. Moreover, the color tone was expressed by DICNIl.

From Table 1, when the content of Coo is increased, the color tone becomes darker.
It can also be seen that even if the amount of CoO added is the same, increasing the Al2O2 content makes the color tone lighter, making it possible to delicately control the color tone. Furthermore, regarding the CoO content, if it was lower than 0.1% by weight like Nal, no coloring occurred, and if it exceeded 5% by weight like Case 18, the bending strength and toughness were extremely poor.

[Margin below]

1st 0b 戊minute; Zirconia + 3solχY□01) table This seal is outside the scope of this invention.

Example 2 Next, instead of Y2O3 as a stabilizer, 9 molχ of Mg
A colored zirconia ceramic obtained in the same manner as in Example 1 except for using O was examined for bending strength, toughness, and color tone. The results are shown in Table 2.

In this case as well, it can be seen that as in Example 1, increasing the Ah03 content makes the color tone lighter, making it possible to delicately control the color tone.

[Margins below] [Effects of the Invention] As shown above, according to the present invention, 0.1 to 5% by weight of Coo as a pigment and 81 to 5% by weight of Coo as a pigment to 100% by weight of the main component consisting of zirconia and a stabilizer. By containing 0.1 to 20% by weight of □03, Ah03 becomes C.

These Co01Al act to lighten the color of O.
By varying the content of z03 within the above range, delicate color tone control can be easily performed, and colored zirconia ceramics having excellent bending strength and toughness can be provided.

Claims (1)

[Claims] A colored zirconia ceramic characterized by containing 0.1-5% by weight of CoO and 0.1-20% by weight of Al_2O_3 with respect to 100% by weight of the main component consisting of zirconia and a stabilizer.