JPH04369909A - Crystal vibrator - Google Patents

Abstract

PURPOSE:To realize the crystal vibrator with high reliability in which excellent durability and adhesive performance is attained, no crack is caused, no unoscillation is caused in a drop test, production of out-gas is less and its service life is long. CONSTITUTION:The crystal vibrator is featured by adhering a metallic electrode and a lead conductor provided to a crystal chip through the use of a conductive adhesives employing (A) an urethane polymer blocked by a bisphenol A or F, (B) a polyhydric alcohol chemical compound and (C) conductive powder as essential components.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crystal resonator which has excellent durability and adhesive properties and is free from cracks.

0002

[Prior Art] A quartz resonator is manufactured by cutting a quartz crystal at a predetermined angle, providing metal electrodes on a thin quartz piece, and bonding the metal electrodes to a lead-out conductor extending from a case cover plate.
It is manufactured by covering a crystal piece with a cover and sealing it, and is widely used for oscillation purposes. Conductive adhesive is used between the metal electrode of this crystal resonator and the lead-out conductor, or between the pad of the semiconductor device and the lead-out conductor, etc., in order to maintain electrical conductivity and maintain mechanical bond between the two. . Conventionally, a two-component epoxy adhesive has been used as this conductive adhesive.

However, conventional conductive adhesives do not have satisfactory properties. For example, there were drawbacks such as the conductive adhesive that coats a thin crystal piece for high frequency use causing cracks in the crystal piece after curing, and some crystal units failing to oscillate during a drop test. In addition, since it is a two-component product, it has short pot life after mixing the two-component products, and a large amount of outgas (released gas) is generated, which may reduce adhesion or affect other products.

0004

[Problems to be Solved by the Invention] The present invention has been made in order to eliminate the above-mentioned drawbacks. The purpose is to provide a crystal resonator that generates a small amount of ion and has a long pot life.

[0005]

[Means for Solving the Problems] As a result of intensive research aimed at achieving the above object, the present inventor has found that the above object can be achieved by using a conductive adhesive having the composition described below. This discovery has led to the completion of the present invention.

That is, the present invention provides metal electrodes and lead-out conductors provided on a crystal piece with (A) a bisphenol block urethane polymer, (B) a polyhydric alcohol compound, and (
C) Conductive powder A crystal resonator characterized by being adhesively fixed with a conductive adhesive containing the following essential components.

The present invention will be explained in detail below.

The crystal piece used in the present invention is a thin piece of about 80 μm thick obtained by cutting a crystal body at a predetermined angle.

The conductive adhesive used in the present invention contains (A) a bisphenol block urethane polymer, (B) a polyhydric alcohol compound, and (C) a conductive powder.

The bisphenol-blocked urethane prepolymer (A) used in the present invention is a blocked isocyanate prepolymer obtained by blocking the terminal active isocyanate groups of the urethane-forming prepolymer and oligomer with a bisphenol-active hydrogen compound. A typical example is one in which polyester or polybutadiene having a terminally active isocyanate is blocked with bisphenol A or bisphenol F. These can be used alone or in combination of two or more. These blocked urethane prepolymers and oligomers are stable at room temperature, but at 120 °C
It has the property of dissociating isocyanate groups when heated to a higher temperature.

The polyhydric alcohol compound (B) used in the present invention is one having a long chain alkyl group in consideration of flexibility and softness, such as polyester-based, polybutadiene-based and silicone-based polyhydric alcohol compounds. is available. Specifically, R-45H manufactured by Idemitsu Petrochemical Co., Ltd.
T, polyethylene glycol, polypropylene glycol manufactured by Sanyo Chemical Co., Ltd., alcohol-modified silicone BY series manufactured by Toray Silicone Co., Ltd., etc., and these can be used alone or in combination of two or more types. The hydroxyl groups of these polyhydric alcohol compounds react with the isocyanate groups dissociated from the urethane polymers and oligomers. The blending ratio of this urethane polymer or oligomer and polyhydric alcohol is determined by dissociated isocyanate groups (NC
O) and the hydroxyl group (OH) of the polyhydric alcohol compound (N
CO/OH) is preferably in the range of 1.0 to 1.2 equivalents. This blending ratio is less than 1.0 equivalent or
If the amount exceeds 1.2 equivalents, the desired properties cannot be obtained, which is not preferable. Further, as a catalyst for promoting this reaction system, dialkyltin dilaurate or the like is generally used.

[0012] Examples of the conductive powder (C) used in the present invention include silver powder, copper powder, nickel powder, and silver powder having a metal layer on the surface, and these may be used alone or in a mixture of two or more. can do. These conductive powders are
In both cases, it is desirable that the average particle diameter is 10 μm or less. If the average particle size exceeds 10 μm, the composition will not become paste-like and the coating performance will deteriorate, which is not preferable. The mixing ratio of conductive powder and resin component is 70/3 by weight.
It is desirable that it is 0 to 90/10. conductive powder,
If it is less than 70 parts by weight, satisfactory conductivity cannot be obtained, and if it exceeds 90 parts by weight, workability and adhesion will deteriorate, which is not preferable.

[0013] The conductive adhesive used in the present invention may contain an organic solvent if necessary to adjust the viscosity. Examples of the solvent include dioxane, hexane, cellosolve acetate, ethyl cellosolve, butyl cellosolve, butyl cellosolve acetate, butyl carbitol acetate, isophorone, etc., and these can be used alone or in combination of two or more. Further, an antifoaming agent, a coupling agent, and other additives may be blended within a range that does not contradict the purpose of the present invention. The conductive adhesive used in the present invention can be produced by thoroughly mixing each raw material component according to a conventional method, and then kneading the mixture using, for example, three rolls, followed by degassing under reduced pressure.

[0014]

[Examples] Next, the present invention will be explained by examples.
The present invention is not limited to these examples. In Examples and Comparative Examples, "parts" means "parts by weight" unless otherwise specified.

Examples 1 to 3 The components shown in Table 1 were kneaded three times using three rolls to produce one-component conductive adhesives (A), (B), and (C), respectively.

Comparative Example A commercially available epoxy resin-based solvent-type conductive adhesive (D) was obtained.

[0017] The conductive adhesives (A), (B), (C) and (D) obtained in Examples 1 to 3 and Comparative Examples were applied to a thickness of 80 μm.
A crystal resonator was manufactured by dispensing coating on the electrode part of the crystal piece and the pad part of the semiconductor device, and heating and curing it at 150° C. for 30 minutes. For 30 crystal resonators, crystal piece cracks and 10 from 75cm top method
The number of samples that failed to oscillate after being dropped twice was measured, and the results are shown in Table 1.

[0018]

[Table 1]

[0019]

Effects of the Invention As is clear from the above explanation and Table 1, the crystal resonator of the present invention has excellent durability and adhesion, does not generate cracks, does not oscillate in a drop test, and has no outgas. It is highly reliable, has a long pot life, and generates little amount of carbon dioxide.

Claims (1)

[Claims] Claim 1: The metal electrode provided on the crystal piece and the lead-out conductor are bonded together using a conductive adhesive containing (A) a bisphenol block urethane polymer, (B) a polyhydric alcohol compound, and (C) a conductive powder, the following being essential components: A crystal resonator characterized by being adhesively fixed with an adhesive.