JPS6234714B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for partially plating ceramics. The following is a conventional method for partially plating ceramics. That is, a desired pattern is masked on a ceramic material using an alkali-soluble resist ink, and after drying, degreasing, and etching, tin ions are attached using a tin solution containing stannous chloride as the main component, and then palladium chloride is applied. By reacting palladium ions on tin ions with a palladium solution as the main component, a metal palladium catalyst is deposited and electroless plating is performed. After washing with water, the resist ink portion is peeled off to perform partial plating. However, according to this method, tin ions and palladium ions adhere not only to the ceramic portion but also to the resist ink portion and act as catalysts, so that plating is deposited not only on the ceramic portion but also on the resist ink portion. For this reason, it is necessary to separately peel off only the resist ink portion after plating. Furthermore, in this conventional method, attempts have been made to selectively prevent the above ions from adhering to the resist ink area by varying the tin ion concentration and palladium ion concentration; It cannot be attached. As a result of continuing research to resolve the above-mentioned difficulties of conventional methods, the present inventor came up with a completely new idea that it would be possible to perform partial plating by peeling off the resist ink before the electroless plating process, and further As a result of continued research, the present invention was finally completed.
That is, in the present invention, desired areas are masked using an alkali-soluble resist ink on the ceramic surface, and after drying, a colloidal catalyst of palladium and tin is attached, and the resist ink is dissolved as the catalyst is activated by contacting with an alkaline solution. The present invention relates to a method for partially plating ceramic, which is characterized by removing the ceramic and then performing electroless plating. In the method of the present invention, first, masking is performed on a ceramic material in a desired pattern using resist ink. Next, through the usual steps of drying, degreasing, washing, and etching, a mixed colloid of tin and palladium is applied to both the ceramic surface and the resist ink surface using a colloidal solution of tin and palladium. This colloid has poor activation power as it is and can be activated with an alkaline solution. At this time, at the same time as activation, the resist ink with attached tin and palladium is dissolved and removed, leaving the tin and palladium catalyst (activated) only in the areas to be plated. Then, by washing with water and electroless treatment, plating is deposited in a desired pattern. A wide variety of ceramic materials can be used in the present invention.
Examples include pure alumina-based, barium titanate-based, ferrite-based, and zircon-based ceramics. There are no particular restrictions on the shape of the ceramic material,
Various shapes can be used. As the resist ink, one that is soluble in an alkaline solution is used. For example, an alkali-soluble resist ink containing a malonic acid resin as the resin component, a cellosolve solvent such as ethyl cellosolve as the solvent, and an inorganic pigment is preferably used. Ru. The thickness of the ink when masking is performed using the ink is not particularly limited and may be a conventional thickness, for example, about 10 to 50 microns. As the colloidal liquid of tin and palladium, a liquid in which these metal colloids are dispersed in water is usually used. These ordinary alkaline solutions can be used to activate metal colloids,
For example, an aqueous solution of caustic soda or caustic potash can be exemplified as a typical example. The electroless plating itself may be carried out according to the conventional method. In order to make the features of the present invention more clear, the differences between the method of the present invention and the conventional method will be shown below using drawings. Figures 1 to 3 are all simulated diagrams of the conventional method. Figure 1 shows the state after Sn and Pd ions have been deposited, and Figure 2 shows the state after electroless plating. FIG. 3 shows the state after the resist ink has been peeled off. In these figures, 1 is a ceramic material, 2 is an electroless plating film, 3 is a resist ink coating, 4 is Sn, and 5 is Pd. As shown in Figure 1, in the conventional method, the resist ink film 3 also contains Sn and
When Pd ions are attached and electroless plating is applied thereto, a plating film is formed on the resist ink film 3 as shown in FIG. When the resist ink is then removed, a plating film remains as shown in FIG. 3, and the plating film is also formed on the masking portion. Therefore, according to the conventional method, an excess plating film 6
must be removed separately. Since this removal is carried out according to conventional mechanical means, it is difficult to completely remove the ceramic material, and in addition, it has an undesirable effect on the ceramic material, and in severe cases can cause cracks and cracks. On the other hand, FIGS. 4 to 6 are schematic illustrations of the method of the present invention, and the numbers in the drawings indicate the same things as in FIGS. 1 to 3. Figure 4 shows the state after Sn and Pd colloids are attached.
FIG. 5 shows the state after resist ink peeling and activation, and FIG. 6 shows the state after electroless plating.
As shown in Figure 4, Sn and Pd colloids adhere to the ceramic material and the resist ink film, but by treatment with an alkaline solution, the tin is dissolved and the palladium colloids are activated and remain, and the resist ink is After being removed, the state shown in FIG. 5 is obtained. Next, when electroless plating is applied, a state as shown in FIG. 6 is obtained, and the plating is deposited in a desired pattern. Example As shown in FIG. 7, a checkered pattern was printed on a ceramic material (96% alumina plate) using resist ink (malonic acid resin ink). This was dried at 60°C, degreased with an acidic chelate substance, washed with water, and etched with hydrofluoric acid. The etched plate was then immersed in a colloidal solution containing 3% Sn and 0.02% Pd for 5 to 7 minutes, immersed in an aqueous NaOH solution for 3 to 5 minutes, washed with water, and dried. Next, electroless plating was performed using an electroless nickel plating bath or an electroless copper plating bath at 30° C. for 30 minutes, followed by washing and drying. This was repeated 10 times to investigate the ratio of precipitation to the resist ink. The results are shown in Table 1. Comparative Example The etched material in the above example was immersed in an aqueous solution containing 3% stannous chloride for 2 minutes, then immersed in a 0.02% palladium chloride aqueous solution for 2 minutes, washed with water and dried under the same conditions as in Example 1. Electroless plating was performed. The results are also listed in Table 1. 【table】

[Brief explanation of the drawing]

1 to 7 are diagrams schematically showing the conditions at each step of the plating method. In the figure, 1 is a ceramic material, 2 is a plating film, 3 is a resist ink film,
4 represents Sn and 5 represents Pd.

Claims (1)

[Claims] 1 Mask the desired areas on the ceramic surface using an alkali-soluble resist ink, and after drying, attach a colloidal catalyst of palladium and tin, bring it into contact with an alkaline solution to activate the catalyst, and dissolve and remove the resist ink. A partial plating method for ceramics, which is characterized in that electroless plating is then performed.