Patent Translate Powered by EPO and Google Notice This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate, complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or financial decisions, should not be based on machine-translation output. DESCRIPTION JPH0477572 [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric buzzer and a conductive paint for forming an electrode thereof. [Prior Art] As shown in the first time, a piezoelectric buzzer has an electrode 2 formed on the screen of a piezoelectric vibrator 1 and a lead wA 4 connected to this electrode 2 directly or through a metal elastic body 3 It is. Silver paste is conventionally used as the electrode 2 in the second piezoelectric buzzer, and as shown in FIG. 8, the silver paste is pressed by printing! The electrode 2 is formed by coating on the screen of the vibrator 1, and thereafter, drying, baking, and the like are performed by the flow shown in the same drawing, and a piezoelectric buzzer is manufactured. [Problems to be Solved by the Invention] The piezoelectric vibrator 1 of the piezoelectric buzzer is desired to be as thin as possible from the viewpoint of vibration characteristics. However, if it is made thinner, in the conventional manufacturing method such as drying and baking, silver direct gray voltage may be generated in the electrode 2 after the baking (about 800 ° C.) and a DC voltage is applied in a wet atmosphere, and piezoelectric vibration There is a problem that the thickness of the child 1 can not be reduced. As a method of achieving the above-mentioned thinning, gold l! There is known a method of heating and curing a coating of a conductive paste consisting of silver powder and a thermosetting resin, but in this case the conductivity is lowered and the adhesion of the coating on the insulating substrate is poor. was there. In addition, the capacity (capacitance, resonance characteristics) of the piezoelectric vibrator according to this method is lower than in the case of the method using the drying and baking, and thus there is a problem that sufficient sound pressure can not be obtained. Therefore, the object of the present invention is to solve the problems of the above-mentioned conventional silver paste, (1) having good conductivity, (2) easy screen printing and intaglio printing, and (2) adhesion of a coating on insulating substrate Good in properties, can form fine line circuits, has excellent solderability and strength on soldered films, can maintain the conductivity of conductive circuits in solder coats 04-05-2019 1 for a long time, improves electrode capacity It is to provide a gold paste that can be [Means for Solving the Problems] As means for solving the above problems, in the present invention, a total of 100 of 85 to 96% by weight of metal gold powder A, 815 to 4% by weight of resol type phenolic resin, and both A and B It consists of 0.1 to 8 parts by weight of saturated fatty acid or unsaturated fatty acid or metal salt thereof and part by weight of carbon black, and said resol type phenol resin B is 2-substituted by 1 part by weight. , M-, n-, a-, b-, c-, infra-red transmittance by infrared spectroscopy of: body, 2.4-2 substitution, 2.4.6-3 substitution, methylol group, dimethylene ether, phenyl group When it is assumed that each transmittance is between (i) -0, am 1.2 (ro)-0, 8 to 1.2 (ha)-0, 8 to 1.2 (ni)-1 Piezoelectric buzzer electricity consisting of pastes that satisfy the relationship Than it was adopted for forming paint. The weight part of carbon black mixed in the gold paste and the particle size may be appropriately determined by experiments etc. For example, 0.5 to 20 parts by weight, preferably 100 parts by weight in total of the A and B. The particle size thereof is, for example, 15 (10- "am) nm to 1 n-, preferably 15 nm to 50 n-. Moreover, the whole powder particle of the said gold paste can be set as 0.1-20 # 11, and it can be set as an electrode, Preferably it is set as 1- or less. A carbon blank may be further added as a gold powder particle size in this range. Then, on the screen of the piezoelectric vibrator, an electrode made of the paste having the above-described configuration is formed, and a piezoelectric buzzer formed by connecting a lead wire directly or via an elastic body to this electrode is configured. [Function] In the gold paste according to the present invention configured as described above, when the compounding amount of metal gold powder is less than 851% by mass, the solderability deteriorates and conversely, when it exceeds 96% by weight, the metal gold powder is sufficiently It is not bound, the resulting electrode is also poor, the desired soldering strength can not be obtained, the conductivity is lowered and the screen printability is also deteriorated. Preferably, it is 88% by weight or more, more preferably 90 to 93% by weight in the composition with the resin. With respect to the resol type phenol resin to be used, its stoichiometry, the amount of 2-1 substitution is λ, the amount of 2.4-2 substitution is μ, the amount of 2.4.6-3 substitution is ν, the amount of methylol group is α When the amount of dimethylene ether is β and the amount of phenyl group is γ, it means that -n of the above constitution is smaller. That is, it means that ν is larger in the 2.4.6-3 substitution amount than the 2-1 substitution amount λ and the 2.4-2 substitution amount μ. Electricality is improved. However, conversely, the electrode tends to be hard and brittle, and the physical properties deteriorate. Also, when β is small, the solderability of the electrode is poor, and if-is large, the conductivity of the electrode is poor. α Therefore, as a resol-type phenolic resin which makes the hardness of the obtained electrode appropriate and combines good conductivity and solderability, it becomes α α shown in the above-mentioned constitution. That is, it means that the amount of methylol group α is larger than the amount of dimethylene ether β and the amount of phenyl group T. In general, when the 2.4.6-3 substitution amount 大 き く is increased, it is suitable that the crosslink density of the resol-type phenol resin is thick and nna is 1.2 to 1.5. When the amount of the resol-type phenolic resin is less than 4% by weight, the 04-05-2019 2 metal gold powder is not sufficiently bound, the obtained electrode is also brittle, the conductivity is lowered and the screen printability is deteriorated. On the other hand, when it exceeds 15% by weight, solderability is not preferable. With saturated fatty acids or unsaturated fatty acids or metal salts thereof, in the case of saturated fatty acids, C16-C20 palmitic acid, stearic acid, arachic acid and the like, in unsaturated fatty acids, such as C16-18 carbon seamarins Acids, oleic acid, rylic acid and the like, and in the case of their metal salts, salts with metals such as potassium, copper, aluminum, sodium, zinc and the like. The use of these dispersants is preferable because it promotes the fine dispersion of the metal gold powder in the resin and forms an electrode with good conductivity in the combination of the metal gold powder and the resol-type phenolic resin. The compounding amount of the saturated fatty acid or the unsaturated fatty acid or the metal salt thereof is used in the range of 0.1 to 8 parts by weight, preferably 1 to 3 with respect to 100 parts by weight in total of the metal gold powder and the resol type phenolic resin. It is a weight part. When the compounding amount of the dispersant is less than 0.1 parts by weight, the fine dispersibility of the metal gold powder can not be expected, and conversely, when it exceeds 8 parts by weight, the conductivity of the electrode is lowered to make the electrode and the piezoelectric vibrator It is not preferable because it causes a decrease in adhesion with the In the gold paste according to the present invention, conventional organic solvents can be used appropriately to adjust the viscosity. For example, known solvents such as butyl carpitol, butyl carpitol acetate, butyl cellosolve, methyl isobutyl ketone, toluene, xylene and the like. [Examples] With the compounding ratio shown in Table 1, Example 1 has gold powder particle size: 0.8μ, 1.0μ, 1.3n, 3.0μ, 5. The gold paste was prepared by kneading 7 kinds of oμ, 15fm and 20m with a three-wheeled roll for 20 minutes. In Example 2, the gold powder diameter = 5.0 μ, and the carbon black particle diameter: 40 nm. At 25 nm and 16 nm, the weight ratio to gold powder: 1%, 2.5%, 4%, 5%, 6%, 7.5%, 9%, and select one as appropriate. The gold paste was prepared by kneading. As the resol type phenol resin, one having an infrared transmittance ratio of-= 1.31 was used. Table (Weight ratio) As shown in FIG. 2, the gold paste of Example 1.2 adjusted in this manner is applied to the screen of the substrate of the piezoelectric vibrator 1 by screen printing to form the electrodes 2 as shown in FIG. And measured their own cabality. The results of Example 1 are shown in FIG. 3, and the results of Example 2 are shown in FIG. From the results, it is understood that the smaller the diameter of the metal powder, the larger the capacity, and the larger the carbon black content (addition amount), the larger the capacity. When the conductivity, adhesion, solderability, solderability and printability were examined, sufficient conductivity could not be obtained with a gold powder diameter of 0.5 n or less, and with 1 ° On or less. Although the solderability worsened, it was satisfactory in other respects. As described above, when the particle size of the metal gold powder is reduced, problems of the conductivity and the solderability occur on the other hand, while the capacity is improved. It is 04-05-2019 3 considered that this is because the smaller the grain size on the surface of the false board (plate voltage oscillator 1), the more the welding progresses and the bonding degree is improved. For this reason, a plurality of pastes are applied so that the electrodes 2 are formed in a plurality of layers, and the piezoelectric vibrator 1 side has small diameter grains, and leads f! It turns out that it is good to make 4 side the large diameter grain. In addition, metal gold powder diameter: 5. On, in the carbon black diameter: 37 nm, the compounding ratio (weight ratio) of metal gold (Ag) to resole type phenol resin (Re) 86: 14.8 B: 12.90: 10.92: 08.93: 07 A gold paste of .94: 06 was formed, whereby the electrode 2 was formed in the same manner as described above, the carbon black loading was changed, and the relationship between the loading and the coverage is shown in FIG. In FIG. 6, the coverage of metal gold powder (particle size: 5 n) (weight ratio with resin, for example, weight ratio with resin, for example, 88: gold powder: resin-88: 12) is covered by the gold paste electrode and its charge Show the relationship with FIG. 7 shows the degree of change in specific resistance of the gold paste electrode in which the blending ratio of metal gold powder (diameter 5 um) and carbon blank (diameter, 40 nm, 25 nm, 16 nm) was changed. In this case, metal gold powder: resin was 92: 8 (% by weight). [Effects of the Invention] Since the present invention is configured as described above, a capacity electrode close to that of a conventional silver paste in a state where various performances such as conductivity, screen printability, adhesion and solderability are well maintained. It can be done. For this reason, the reduction of the sound pressure is not caused, the productivity is improved because the baking is not required, and there is no possibility of the migration under the wet atmosphere of the baking, so that the thinning of the piezoelectric vibrator can be achieved. [0002] Brief description of the drawings [0003] 1 is a schematic diagram of an example of the piezoelectric buzzer according to the present invention, FIG. 2 is a production explanatory view of the same side, FIG. 3 is a relation diagram of metal gold powder diameter and capacity, and FIG. Figure 5 shows the relationship between carbon blank addition and capacity Figure 6 shows the relationship between metal gold powder loading and capacity Figure 7 shows the relationship between carbon black content and specific resistance FIG. 8 is a production explanatory view of a conventional example. 1 · · · Piezoelectric vibrator, 2 · · · · · · · · · · · · · · · · · · · · · metal elastic body, 4 · · · · · · lead wire. Patent Assignee Tack Electric Wire Co., Ltd. Attorney Attorney Futaba Fig. 2 Filled amount of gold powder (Weight it 1%) Fig. 5 Carbon black addition amount (% by weight) Fig. 7-o-160 m-o- 04-05-2019 4 25 nm Fig. Figure 04-05-2019 5
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