KR101179050B1 - Method for producing pink colored zirconia ceramics - Google Patents

Abstract

The present invention comprises the steps of mixing erbium oxide (Er ₂ O ₃ ) to zirconium oxide (ZrO ₂ ); Preparing a molded powder by adding water corresponding to 20 to 50% by weight of the total amount of the mixture to the mixture and then granulating the mixture; And it provides a method for producing a pink zirconia ceramics comprising the step of preparing a molded body with the molded powder and calcining the molded body and the pink zirconia ceramics prepared thereby.

Zirconia, Erbium Oxide, Ceramics

Description

Manufacturing method of pink zirconia ceramics {METHOD FOR PRODUCING PINK COLORED ZIRCONIA CERAMICS}

The present invention relates to a method for producing pink zirconia ceramics. More specifically, the present invention relates to a method for producing zirconia ceramics exhibiting a pink color development effect while maintaining the properties of zirconia even when fired at a high temperature, and to pink zirconia ceramics produced thereby.

Zirconia ceramics, which have excellent properties of high toughness, high wear resistance and high strength, have been mainly used as structural materials for mechanical parts. Recently, the range of use of zirconia ceramics is expanding. Thus came zirconia swords, scissors, and the like. In addition, zirconia has been applied to expensive watch parts and decorative articles as a substitute jewelry, and commercialized.

As zirconia is used for jewelry and other ornaments, demand for zirconia in various colors is beginning to emerge. In order to manufacture zirconia ceramics of various colors, it is necessary to be able to maintain colors as they are, even at high temperature firing, without affecting the excellent physical and chemical properties of zirconia.

However, most of the pigments currently produced are low-temperature pigments that exhibit stable color development at firing temperatures of 1300 ° C. or less, and are difficult to apply to high-temperature ceramic products.

Accordingly, the present inventors have conducted various studies to develop zirconia having a stable color development effect even at a high temperature of 1400 ° C. or higher. As a result, it has begun to develop a method for producing pink zirconia ceramics, which stably shows pink even at a high temperature of 1400 ° C or higher.

The present invention is to provide a method for producing pink zirconia ceramics which stably exhibits a pink color development effect and maintains the properties of zirconia ceramics even after high temperature firing.

In addition, the present invention is to provide a pink zirconia ceramics produced by the above method.

In addition, the present invention is to provide a use for the pink zirconia decorative articles and the like.

The present invention comprises the steps of mixing erbium oxide (Er ₂ O ₃ ) to zirconium oxide (ZrO ₂ ); Preparing a molded powder by adding water corresponding to 20 to 50% by weight of the total amount of the mixture to the mixture and then granulating the mixture; And it provides a method for producing a pink zirconia ceramics comprising the step of preparing a molded body with the molded powder and firing the molded body.

According to one embodiment of the invention, the zirconium oxide may be a zirconium oxide powder having an average particle size of 0.3 to 0.8 ㎛.

According to one embodiment of the present invention, the erbium oxide may be added in an amount of 1 to 10 parts by weight based on 100 parts by weight of zirconium oxide.

According to an embodiment of the present invention, in the step of mixing erbium oxide (Er ₂ O ₃ ) to the zirconium oxide (ZrO ₂ ), at least one of a dispersing agent and a binder may be further added to the mixture, the dispersing agent The plasticizer and the binder may each contain 0.1 to 10 parts by weight based on 100 parts by weight of zirconium oxide.

According to one embodiment of the invention, in the step of preparing the molded powder, after adding water corresponding to 20 to 50% by weight of the total amount of the mixture to the mixture, the average particle size of the mixture is 40 to 120 The molded powder may be prepared by granulating to a thickness.

According to one embodiment of the invention, in the step of firing the molded body, the firing temperature may be 1400 to 1600 ℃.

The present invention also provides pink zirconia ceramics produced by the above production method.

The method for producing pink zirconia ceramics according to the present invention is effective in maintaining pink zirconia characteristics while maintaining a stable pink color even at high temperature firing. Therefore, pink zirconia according to the present invention can be used in various ways, such as jewelry, jewelry, watch parts.

The present invention comprises the steps of mixing erbium oxide (Er ₂ O ₃ ) to zirconium oxide (ZrO ₂ ); Granulating the mixture to prepare a molding powder; And calcining the molded body.

Hereinafter, the present invention will be described in more detail.

First, erbium oxide (Er ₂ O ₃ ) is mixed with zirconium oxide (ZrO ₂ ). There is no particular limitation on the zirconium oxide and erbium oxide used in the present invention, and any commercially available one can be used.

The zirconium oxide is preferably zirconium oxide powder having an average particle size of 0.3 to 0.8 ㎛. If the average particle size of the zirconium oxide is less than 0.3 ㎛ may cause a large shrinkage during firing, if it exceeds 0.8 ㎛ may cause a problem that the sintering is not made well and the color of the firing is bad.

The erbium oxide may be added in an amount of 1 to 10 parts by weight based on 100 parts by weight of zirconium oxide. When the erbium oxide is added in less than 1 part by weight, a problem that the pink color development effect is not sufficiently exhibited may occur, and when it exceeds 10 parts by weight, color may become turbid and zirconia properties may decrease.

In the step of mixing the oxidized erbium (Er ₂ O ₃₎ to the zirconium oxide (ZrO _2), the zirconium oxide (ZrO ₂₎ and oxide erbium (Er ₂ O ₃₎ further adding at least one of a dispersant and a binder to the mixture can do.

The dispersant serves to evenly distribute the solids (powder) in the ceramic composition. In the present invention, any dispersant known in the art may be used without limitation. Specific examples include an ammonium dispersant and an acrylic dispersant, but are not necessarily limited thereto.

The dispersant is preferably included in 0.1 to 10 parts by weight based on 100 parts by weight of zirconium oxide. When the content of the dispersant is less than 0.1 parts by weight, the effect of dispersant addition may be insignificant. When the content of the dispersant is more than 10 parts by weight, the remaining ash after firing may affect the properties and the color.

The binder serves to bind each component in the ceramic composition well. In the present invention, any dispersant known in the art may be used without limitation. Specific examples include silica sol, polyvinylalcohol (PVA), kaolin, and the like, but are not necessarily limited thereto.

The binder is preferably included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of zirconium oxide. When the content of the binder is less than 0.1 parts by weight or more than 10 parts by weight, the physical properties of the molded body may be deteriorated.

In addition to the dispersant and / or binder, optionally, a release agent may be further added to facilitate the press. The release agent may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of zirconium oxide. In the present invention, any release agent known in the art may be used without limitation. Specific examples include diethylene glycol monostearate, hydrogenated castor oil, stearic acid, oleic acid, isophthalic acid, and adipic acid. ), Zinc stearate, calcium stearate, ethylene bis (stearamide), oleyl palmitamide, microcrystalline wax, Paraffin wax, carnauba wax, spermaceti wax, cellophane, cellulose acetate, sodium alginate; Polydimethylsiloxane, polyalkylmethylsiloxane, polytetrafluoroethylene, poly (fluoroacrylates), poly (fluoroethers) )), Synthetic polymers such as polyethylene, polypropylene, poly (vinyl alcohol), and the like; Fluorinated compounds such as perfluorolauric acid; It may be at least one selected from inorganic materials such as talc, kaolin, mica, and silica, but is not necessarily limited thereto. In the present invention, in particular, HS LUB LS200 (trade name) or NOPC0 CERA LU 6418 (trade name) of Emerging New Material Co., Ltd. (Korea) can be used.

The zirconium oxide and erbium oxide, and optionally a dispersing agent and / or binder, optionally, a release agent is added and mixed, water is added to the mixture, granulated, and a molded powder is prepared.

The moisture may be added in an amount of 20 to 50% by weight of the total amount of the mixture (zirconium oxide and erbium oxide, a dispersant and / or binder, and optionally a release agent added). If the water content is less than 20% by weight may cause a problem that the spray is not made well, when the water content is more than 50% by weight when the granules are made in the shape of a balloon when making granules after water spraying granules Formation may not occur properly.

The wet mixing mentioned above can be carried out by methods well known in the art.

In the embodiment of the present invention, the water addition and granulation of the mixture was carried out using a spray dryer, which is only one example, the preparation of the granulation and molding powder of the present invention is limited to this method only. It doesn't happen.

In the present invention, after performing the granulation process, spherical particles having an average particle size of 40 to 120 μm constituting the mixture can be obtained as a molding powder. When the average particle size of the molded powder is less than 40 μm or more than 120 μm, there may be difficulty in preparing the molded body. In addition, when the size of the granules is less than 40 μm, the granules are scattered during molding, which makes it difficult to control the density. When the size of the granules is increased to over 120 μm, there are many bubbles after molding due to the pupillary phenomenon formed in the granules, which may result in poor physical properties.

After preparing the molded powder, the molded product is manufactured and calcined with the molded powder. In the production of the molded body, it is possible to make the molded body in various shapes-square, rectangular, circular, etc., and a molding method well known in the art can be used. In the embodiment of the present invention, the dry compression molding method is used, but the molding method of the present invention is not necessarily limited thereto.

The firing temperature may be 1400 to 1600 ℃. The firing temperature is adjustable according to the size of the molded body, which may be usually 1 to 20 hours, but is not necessarily limited thereto. As the firing atmosphere, both oxidizing and reducing firing may be used.

In general, when zirconia ceramics are fired at a high temperature of 1400 ° C. or higher, the pigment used for color development burns out, and thus a desired color development effect cannot be exhibited. However, the present invention has the effect that pink appears well even at a high temperature of 1400 ℃ or more. This is because the optimum conditions for pink color development were made in the preparation of the pink zirconia ceramics of the present invention.

If the firing temperature is less than 1400 ℃ sintering may not be performed well, if the firing temperature is 1600 ℃ or more sintering of the zirconia caused by the physical properties deteriorate or the decomposition of vanadium oxide occurs pink color is not well achieved Problems may arise.

Pink zirconia made according to the production method of the present invention stably pink even at a high temperature of 1400 ° C. or higher and maintains excellent physical properties of zirconia. Therefore, the pink zirconia according to the present invention can be used in various ways, such as jewelry, decorative products or household goods while satisfying the demand for the pink desired by the consumer (see Fig. 1).

Hereinafter, the present invention will be described in more detail through Examples and Test Examples. However, these examples and test examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example

Example 1

100 g of zirconia (Daiji, Japan) and 5 g of erbium oxide (Junsei, Japan) with an average particle size of 0.5 g were mixed together in a ball mill, and then the total amount of the mixture using a spray dryer (drying capacity of 15 L / hr). Water equivalent to 40% by weight of was added and granulation was carried out. At this time, the temperature inside the spray drying chamber was 145 ° C., and a molding powder having an average particle size of 60 μm was obtained at a rotational speed of the disk in the sprayer at 8000 rpm. The molded powder was molded by dry compression molding using a 40 × 6 × 5 mm rod mold, fired for 1 hour in an electric furnace at 1500 ° C., and then naturally cooled to obtain pink zirconia ceramics.

Example 2

Excluding 100 g of zirconia (Daiji, Japan), 5 g of erbium oxide (Junsei, Japan), 1 g of ammonium dispersant (5468CH, Cheil New Material, Korea) and 5 g of PVA217 Pink zirconia ceramics were obtained in the same manner as in Example 1.

Example 3

100 g of zirconia (Daiji, Japan), 5 g of erbium oxide (Junsei, Japan), 1 g of ammonium dispersant (5468CH, Cheil New Material, Korea), 5 g of PVA217 Except that was used in the same manner as in Example 2 to prepare a clockwork ornament using pink zirconia ceramics (see Figure 1).

Test Example

Test Example 1: Ceramics Color Analysis

The color analysis of the pink zirconia obtained in Example 1 was an ultraviolet-visible spectrophotometer (UV-2401PC, Shimatsu, Japan), and the values (L ^* , a ^* , CIE: Commissiom Internationaled I'Eclairage) colorimeter. b ^* ) and the results are shown in Table 1.

[Table 1]

Example L ^* a ^* b ^* One 66.93 10.35 2.48 2 66.73 10.30 2.47

As shown in Table 1, the brightness was about 66.93 or 66.73, and the saturation was a ^* : 10.35 or 10.30 and b ^* : 2.48 or 2.47.

Test Example 2: Physical property analysis

The strength, bending strength and water absorption of the pink zirconia specimens of Examples 1 and 2 and commercially available zirconia (KZ-3YF, Kyoritsu, Japan) as a comparative example were measured by the following method, and the results are shown in Table 2. It was.

-Strength measurement: Universal testing machine (EZ Test, Shimatsu, Japan)

-Absorption rate: KS L 3114

[Table 2]

burglar Absorption rate Example 1 910 0.00% Example 2 904 0.00% Comparative example 896 0.09%

As can be seen through the results in Table 2, it can be seen that the pink zirconia according to the present invention maintains excellent physical properties of the existing zirconia. The pink zirconia according to the invention is thus applicable to jewelries or decorative products.

1 is a photograph showing a clock using a pink zirconia according to an embodiment of the present invention.

Claims (8)

Mixing erbium oxide (Er ₂ O ₃ ) with zirconium oxide (ZrO ₂ ); Preparing a molded powder by adding water corresponding to 20 to 50% by weight of the total amount of the mixture to a mixture of the mixed zirconium oxide (ZrO ₂ ) and erbium oxide (Er ₂ O ₃ ); And Preparing a molded body from the molded powder and firing the molded body; Method for producing a pink zirconia ceramics comprising a. The method of claim 1, The zirconium oxide is a method of producing pink zirconia ceramics, characterized in that the zirconium oxide powder having an average particle size of 0.3 to 0.8 ㎛. The method of claim 1, The erbium oxide is a method for producing pink zirconia ceramics, characterized in that added to 1 to 10 parts by weight based on 100 parts by weight of zirconium oxide. The method of claim 1, In the step of mixing erbium oxide (Er ₂ O ₃ ) to the zirconium oxide (ZrO ₂ ), at least one of a dispersing agent and a binder is added to the mixture method of producing pink zirconia ceramics. 5. The method of claim 4, The dispersing agent and the binder is 0.1 to 10 parts by weight based on 100 parts by weight of zirconium oxide, the method for producing pink zirconia ceramics. The method of claim 1, In the step of preparing the molded powder, by adding water corresponding to 20 to 50% by weight of the total amount of the mixture to the mixture, the molded powder is granulated so that the average particle size of the mixture is 40 to 120 ㎛ Method for producing a pink zirconia ceramics, characterized in that the preparation. The method of claim 1, In the step of firing the molded body, the firing temperature is a method for producing pink zirconia ceramics, characterized in that 1400 to 1600 ℃. delete

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