JP2005217156A - Manufacturing method of three-dimensional injection molded circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a three-dimensional injection molding circuit including a step of performing secondary molding to the surface of a primary molded product other than that on which a circuit is to be formed by using a resin, and eluting the resin in the secondary molding whereby a desired conductor circuit pattern can be formed with high accuracy. <P>SOLUTION: The manufacturing method of the three-dimensional injection molding circuit includes steps of forming a resin layer made of the resin soluble in a low boiling point solvent to the surface other than that on which the circuit of the primary molded product configuring a board of the circuit is to be formed to obtain a secondary molded product, applying a catalysis to part of the surface of the secondary molded product on which the circuit is to be formed, solving and removing the resin layer by making the vapor of the low boiling point solvent and / or liquid drops of the low boiling point solvent by the secondary molding, and forming a conductor circuit layer to the part with the catalysis applied thereto by electroless plating. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a three-dimensional injection molded circuit component in which wiring (conductor circuit) is three-dimensionally formed on the surface of an injection molded product.

  In order to reduce the size of electronic devices and to improve the assembly of electronic devices, there is a need for a technology for rationalizing wiring in the devices. In order to meet this requirement, a three-dimensional injection molded circuit component (MID) in which a conductor circuit (wiring) is three-dimensionally formed on the surface of an injection molded product has been proposed.

  Three-dimensional injection molded circuit components are three-dimensional wiring boards that integrate synthetic resin injection molded products and wiring components, have free three-dimensionality, not only rationalize wiring, but also miniaturization of electronic components, Enables surface mounting. For example, the integration density can be improved by arranging three-dimensional injection molded circuit components in a gap in the device. Since the three-dimensional injection molded circuit component has such excellent features, it is widely applied to semiconductor packages such as light emitting diodes (LEDs), three-dimensional printed wiring boards, mobile phone antenna components, and the like.

  A three-dimensional injection molded circuit component manufacturing method is a one-time molding method in which a plating film of a conductor is formed on the surface of a plating-grade resin molded product, a resist is coated on the film, and a circuit is formed by photolithography. Is mentioned. However, since this one-time molding method is based on photolithography, it is difficult to form a circuit on a vertical surface, and the degree of freedom in forming a conductor circuit is low. In addition, the circuit is formed by etching, so the thickness of the conductor must be increased. There is a problem that is difficult.

  Therefore, a so-called two-time molding method using two types of resins, an easily plating resin and a difficult plating resin, has been proposed. In this method, an easy-plating resin is injection-molded to form a secondary molded product, and a hard-plating resin is injection-molded on the surface other than the portion where the circuit of the primary molded product is to be formed. In this method, plating is performed on a portion to be formed, and the hard-to-platable resin coating layer serves as a plating resist during plating.

  According to the two-time molding method, a circuit can be easily formed on a vertical surface, so that three-dimensional circuit molding can be easily performed, and the thickness of the conductor is also smaller than that of the one-time molding method using etching. Thus, a circuit component having a large allowable current can be obtained.

  However, in this two-time molding method, since the second-molded difficult-to-platable resin coating layer remains in the product as it is, there is a problem that there is a limit to the reduction in size and weight of electronic components. Moreover, since it is necessary to use a resin material excellent in heat resistance, electrical insulation, mechanical strength, chemical resistance, etc. as a hard-plating resin, there is also a problem of increasing the manufacturing cost.

  In order to solve such a problem of the two-time molding method, Japanese Patent Application Laid-Open No. 11-145583 (Patent Document 1) discloses a method of eluting in the middle of the process so that the secondary molded part does not remain in the product. Proposed. That is, (1) a secondary molded product is formed by injecting a water-soluble oxyalkylene group-containing polypinyl alcohol resin into a portion of the surface of a primary molded product made of a plating grade resin other than a portion where a circuit is to be formed. (2) Applying a catalyst such as palladium or gold to the exposed circuit portion, (3) A portion formed by secondary molding (water-soluble oxyalkylene group-containing polypinyl alcohol-based resin layer) A double molding method is disclosed in which the steps of elution in hot water and (4) plating of the catalyst-applied portion to form a circuit are sequentially performed.

However, in this method, since the secondary molded part (coating layer) is formed using a water-soluble oxyalkylene group-containing polyvinyl alcohol resin, hydrochloric acid, sulfuric acid, etc. used in the catalyst application step and the catalyst activation step are used. The coating layer is swollen and partially dissolved by the treatment liquid containing the inorganic acid. As a result, it becomes difficult to form a desired conductor circuit pattern with high accuracy. In particular, there is a problem that this tendency becomes more prominent as the circuit pitch becomes finer, and the solution has been desired.
JP-A-11-145583 (Claim 1)

  The present invention is a method for producing a three-dimensional injection molded circuit component comprising a step of subjecting a surface of a primary molded product to a surface other than a portion where a circuit is to be formed, and performing a secondary molding with a resin and eluting the secondary molded resin. Therefore, it is an object to provide a method capable of accurately forming a desired conductor circuit pattern.

  The present inventor uses a resin that is soluble in a low-boiling solvent for secondary molding, and elution of the resin is performed by contacting the vapor of the low-boiling solvent and / or droplets of the low-boiling solvent, It has been found that a desired conductor circuit pattern can be formed with high accuracy, and the present invention has been completed.

  According to the present invention, as a first aspect, a secondary resin layer is formed by forming a resin layer made of a resin soluble in a low boiling point solvent on a surface other than a portion where a circuit is to be formed of a primary molded product constituting a circuit component substrate. A step of obtaining a molded product, a step of applying a catalyst to a portion of the surface of the secondary molded product where a circuit is to be formed, and after applying the catalyst, the secondary molded product is treated with the vapor of the low boiling point solvent and / or the low A step of dissolving and removing the resin layer by contacting with a droplet of a boiling point solvent, and a step of forming a conductive circuit layer by electroless plating on the catalyst application portion after the resin layer is dissolved and removed. A method for manufacturing a three-dimensional injection molded circuit component is provided.

  According to a second aspect of the present invention, a resin layer made of a resin soluble in a low boiling point solvent is formed on the surface of a primary molded product constituting a circuit component substrate other than a portion where a circuit is to be formed. A step of obtaining a secondary molded product, a step of applying a catalyst to a portion of the surface of the secondary molded product where the circuit is to be formed, and after applying the catalyst, electroless plating is applied to a portion of the secondary molded product where the circuit is to be formed And a step of dissolving and removing the resin layer by bringing the secondary molded product into contact with vapor of the low boiling point solvent and / or droplets of the low boiling point solvent after performing electroless plating. A method for manufacturing a three-dimensional injection molded circuit component is provided.

  The primary molded product in the configuration of claim 1 or 2 constitutes a circuit component substrate, and is an easily-platable material that is easy to form electroless plating on its surface (commercially available as a plating grade). Etc.). Such an easy-plating material is improved so that fine irregularities are formed on the surface of the molded product by etching. Generally, an inorganic filler is added, and this etching process is performed by etching. As the filler dissolves or falls off, irregularities are formed on the surface of the molded product. As a result, the catalyst necessary for electroless plating can be retained, and a plating film with high adhesion can be formed. The shape of the primary molded product conforms to the external shape of the three-dimensional injection molded circuit component, and is obtained by injecting and molding a resin or the like that is commercially available as a plating grade into a cavity that matches the external shape. It is done.

  On the surface of the primary molded product thus obtained, a resin layer made of a resin soluble in a low-boiling solvent is formed (secondary molding) to obtain a secondary molded product. The resin layer is formed in a portion other than a portion where a circuit is to be formed. That is, for the part where the circuit is to be formed, the surface of the primary molded product is exposed even after the secondary molding, and all other parts are covered with the resin layer.

  In the configuration of claim 1, after the secondary molding, the surface of the secondary molded product where the circuit should be formed, that is, the portion where the resin layer soluble in the low-boiling solvent is not formed is not present. A catalyst for electroplating is applied. Examples of the catalyst include catalysts based on palladium, gold and the like. Application | coating of this catalyst can be performed by a well-known method, and activation of a catalyst is performed with provision of a catalyst normally. For example, a method in which a secondary molded product is immersed in a mixed catalyst solution of tin and palladium and then activated with an acid such as hydrochloric acid and sulfuric acid to deposit palladium on the surface. A relatively strong reducing agent such as stannous chloride is used. Examples include a method of adsorbing on the surface, immersing in a catalyst solution containing noble metal ions such as gold, and depositing gold on the surface.

  After the application of the catalyst, the secondary molded product is brought into contact with the low boiling point solvent vapor and / or the low boiling point solvent droplets, and the resin layer is dissolved and removed. The structure of claim 1 is characterized in that the resin layer is dissolved and removed before electroless plating is performed. When the resin layer is dissolved and removed after electroless plating or further electroplating, the plating is also deposited on the resin layer, and the circuit layer is removed when the resin layer is removed. Problems such as the occurrence of a resin layer remaining in the product and a decrease in accuracy are likely to occur. If the circuit pitch is narrow, the presence of the resin layer may result in insufficient ion supply during plating, and the edge plating may be thin, and in extreme cases, there may be a problem of no plating. However, the configuration of claim 1 is preferable because such a problem does not occur.

  The low boiling point solvent used for dissolving and removing the resin layer is not particularly limited as long as it dissolves the resin layer and has a low boiling point, but alcohol solvents such as ethanol, n-propanol, isopropanol, 1-butanol and the like. , Hexane, octane, cyclohexane, toluene and the like, and isopropyl alcohol (hereinafter referred to as IPA) is preferred. By using the organic solvent, there is no problem that the imparted catalyst, for example, palladium is dissolved and removed in the step of dissolving and removing the resin layer.

  Furthermore, the present invention is characterized in that the resin layer is dissolved and removed by contact of the solvent vapor or solvent droplets with the resin, not by immersing the secondary molded product in a low boiling point solvent. Conventionally, the removal of the resin layer of the secondary molded product has been performed by immersing the secondary molded product in a solvent that dissolves the resin. However, when the resin is melted at once for a large number of secondary molded products, there is a problem in that the resin layer cannot be removed sufficiently and the residue remains, resulting in a low yield.

  Such a problem is considered to be caused by the treatment liquid not penetrating into the part where the secondary molded products overlap each other. As a countermeasure, the secondary molded products are loosened by a method using a large amount of solvent or by vigorous stirring. A method can be considered. However, when a large amount of solvent is used, the cost increases and a large amount of waste liquid is generated, which causes environmental problems. Further, even if vigorous stirring is performed, it is difficult to completely loosen the secondary molded products. On the other hand, if excessive stirring is performed, the product is damaged and the yield is reduced.

  Furthermore, in the case of dipping, if the washing with the solvent after dipping is not sufficient, the dissolved resin may re-adhere to the part where the circuit is to be formed, that is, the part to which the catalyst is applied. There is also a problem of causing plating defects in the plating forming process such as electroless plating and the like.

  As a result of studying to solve such problems, the present inventor has found that the method of contacting the solvent vapor or solvent droplets with the resin can achieve a high yield with a small amount of solvent, rather than the method of immersion. I found it.

  In the structure of Claim 1, after melt | dissolving and removing this resin layer, a conductor circuit layer is formed in this catalyst provision part by electroless plating. Furthermore, when forming a dissimilar metal layer on the obtained electroless plating layer, for example, when plating gold for improving corrosion resistance, or ensuring the thickness of the conductor circuit layer from the viewpoint of strength and application of the conductor circuit layer When necessary, electroless plating of other metals, electroplating, or the like is performed subsequent to electroless plating. By such plating, a conductor circuit layer is formed to obtain a three-dimensional injection molded circuit component.

  According to the second aspect of the present invention, after the secondary molding, electroless plating is performed on the portion of the secondary molded product where the circuit is to be formed. Before applying electroless plating, catalyst application (including catalyst activation) is required, and catalyst application is performed by the same method as described above.

  As in the case of the configuration of the first aspect, electroplating or the like may be performed subsequent to electroless plating. After the conductive circuit layer is formed by electroless plating, or electroless plating and other subsequent plating, etc., the secondary molded product is made into vapor of the low boiling point solvent and / or droplets of the low boiling point solvent. By contacting, the resin layer is dissolved and removed, and a three-dimensional injection molded circuit component is obtained. Further, for example, after electroless plating, the resin layer is dissolved and removed, and then electroplating is performed to form a conductor circuit layer to obtain a three-dimensional injection molded circuit component. The contact with the low boiling point solvent vapor and / or the low boiling point solvent droplets is the same as in the case of the constitution of the first aspect.

  In addition, in the configuration of claim 2, since plating such as electroless plating is performed before the dissolution and removal of the resin soluble in the low boiling point solvent, it is difficult to form the plating on the surface of the resin. A hard-to-platable resin is preferred.

  The method of contacting the secondary molded product with the low boiling point solvent vapor and / or the low boiling point solvent droplets in the constitutions of claim 1 and claim 2, wherein the secondary molded product is a reflux atmosphere of the low boiling point solvent. The method of putting in is illustrated. That is, the low-boiling point solvent is stored in the lower part, and the secondary molded product is placed between the low-boiling point solvent and the condenser in a container provided with a condenser in the upper part. The low boiling point solvent vapor is heated by heating, and the secondary molded product is brought into contact with the low boiling point solvent vapor, and the low boiling point solvent droplet falling from the upper condenser is also contacted. Preferably exemplified.

  The contact between the secondary molded product and the low boiling point solvent vapor and / or the low boiling point solvent droplet holds the secondary molded product in a container through which the low boiling point solvent vapor and droplets can pass, It is preferable to stir or vibrate the container since the secondary molded products are loosened and contact with vapor and droplets is sufficiently performed. Claim 3 corresponds to this preferred embodiment, and is a method of manufacturing a three-dimensional injection molded circuit component according to claim 1 or claim 2 above, wherein the secondary molded product and the low boiling point solvent vapor and / or The contact with the low-boiling solvent droplets is carried out while holding the secondary molded product in a container through which the vapor and droplets of the low-boiling solvent can pass and stirring or vibrating the container. A method of manufacturing a three-dimensional injection molded circuit component is provided.

  As such a container, a basket-like container (barrel) made of a net that passes through steam or droplets and has a smaller mesh than the secondary molded product so that the secondary molded product does not fall off is preferably exemplified. The

  The primary molded product is usually formed by injection molding of a synthetic resin. Claim 4 corresponds to this aspect, and is a method of manufacturing the above three-dimensional injection molded circuit component, wherein the primary molded product is formed by injection molding of a synthetic resin. The present invention provides a method for manufacturing an original injection molded circuit component.

  Synthetic resins used for the primary molding include super engineering plastics such as liquid crystal polymer (LCP) and polyphenylene sulfide (PPS) resins, thermoplastic polyester resins such as polybutylene terephthalate (PBT) and polyethylene terephthalate (PET), polyamide 6, Examples thereof include polyamide resins such as polyamide 66, polyamide 46, polyamide 6T, and polyamide 9T. As these synthetic resins, those commercially available as plating grades are preferable.

  The surface of the primary molded product formed by injection molding or the like of such a synthetic resin is preferably roughened in order to improve the adhesion with the resin layer to be electrolessly plated or secondary molded. Claim 5 corresponds to this preferred embodiment, and is a method for producing the above three-dimensional injection molded circuit component, characterized in that the resin layer is formed after roughening the surface of the primary molded product. A method for manufacturing a three-dimensional injection molded circuit component is provided.

  Examples of the surface roughening method include a method in which an alkaline aqueous solution such as sodium hydroxide or potassium hydroxide is heated to 50 to 90 ° C., and the primary molded product is immersed therein for about 1 to 60 minutes. Other methods can also be applied. In the case of the configuration of claim 2, if desired, a catalyst for electroless plating can be added to the synthetic resin.

  Secondary molding, that is, formation of a resin layer made of a resin that is soluble in a low boiling point solvent, for example, in a mold (secondary mold) having a cavity with a void on the surface excluding the circuit portion to be formed This is performed by a method in which a primary molded product is set and a resin soluble in the low-boiling solvent is injected into the cavity. Claim 6 corresponds to this preferred embodiment, and is a method of manufacturing the above three-dimensional injection molded circuit component, wherein the resin layer made of a resin soluble in a low boiling point solvent is formed by injection molding of the resin. The present invention provides a method for producing a three-dimensional injection molded circuit component.

  As described above, IPA is preferable as the low boiling point solvent. Claim 7 corresponds to this preferred embodiment, and is a method of manufacturing a three-dimensional injection molded circuit component, wherein the low boiling point solvent is IPA. It is to provide.

The resin soluble in the low boiling point solvent is not particularly limited as long as it is soluble in the low boiling point solvent such as IPA. For example, a polyamide resin obtained by subjecting polyamide (A) and polyamide polyamine (B) to an amide exchange reaction,
(1) Polyamide (A)
a) a dicarboxylic acid component containing a dimer acid having a dimer content of 65% by weight or more or an amide-forming derivative thereof in an amount of 20 equivalent% or more of the total carboxyl groups;
b) The following formula (I)

〔式中、Ｒ^１は、それぞれ独立に水素原子又は炭素原子数１〜６のアルキル基であり、Ｙは、水素原子、ＲＮＨ_２又はＲＯＨ（Ｒは、炭素原子数１〜６のアルキレン基）である。〕で表されるピペラジン化合物、及び
下記式（II）

[Wherein, R ¹ is independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and Y is a hydrogen atom, RNH ₂ or ROH (R is an alkylene group having 1 to 6 carbon atoms). It is. A piperazine compound represented by formula (II):

〔式中、Ｒ^１はそれぞれ独立に水素原子又は炭素原子数１〜６のアルキル基であり、Ｒ^２は二価の脂肪族炭化水素基であり、Ｙは、水素原子、ＲＮＨ_２又はＲＯＨ（Ｒは、炭素原子数１〜６のアルキレン基）である。〕で表されるジピベリジル化合物からなる群より選ばれる少なくとも一種の含窒素複素環化合物を全アミノ基の２０当量％以上含有するジアミン成分を、
全アミン当量の全カルボキシル当量に対する比が０．８：１〜１．３：１の範囲内で重縮合して得られるポリアミドであり、
（２）ポリアミドポリアミン（Ｂ）が、
ｃ）二量体含有量が６５重量％以上のダイマー酸又はそのアミド生成可能な誘導体を、全カルボキシル基の２０当量％以上含有するジカルボン酸成分と、
ｄ）ポリアルキレンポリアミンを、
全アミン当量の全カルボキシル当量に対する比が１．３：１〜３．０：１の範囲内で重縮合して得られるポリアミドポリアミンであり、かつ、
（３）アミド交換反応後に下記物性
ｉ）軟化点が８０〜１９０℃、
ii）酸価が０〜５ｍｇＫＯＨ／ｇ、
iii）アミン価が１０〜１００ｍｇＫＯＨ／ｇ、
iv）２００℃で測定した溶融粘度が３５０〜８０，０００ｍＰａ・Ｓ、及び
ｖ）濃度３０重量％の酢酸水溶液１００ｍｌに６０℃で３０分間浸漬して測定した溶解速度が０．２ｍｍ／３０分以上
を有することを特徴とするポリアミド樹脂が好ましく例示される。請求項８は、この好ましい態様に該当し、上記の三次元射出成型回路部品の製造方法であって、低沸点溶剤に可溶な樹脂が、上記のポリアミド（Ａ）とポリアミドポリアミン（Ｂ）とをアミド交換反応させてなるポリアミド樹脂であることを特徴とする三次元射出成型回路部品の製造方法を提供するものである。

[Wherein, R ¹ is independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R ² is a divalent aliphatic hydrocarbon group, and Y is a hydrogen atom, RNH ₂ or ROH ( R is an alkylene group having 1 to 6 carbon atoms. A diamine component containing at least one nitrogen-containing heterocyclic compound selected from the group consisting of the dipiveridyl compounds represented by the formula:
A polyamide obtained by polycondensation within a ratio of total amine equivalent to total carboxyl equivalent of 0.8: 1 to 1.3: 1,
(2) Polyamide polyamine (B)
c) a dicarboxylic acid component containing a dimer acid having a dimer content of 65% by weight or more or an amide-forming derivative thereof in an amount of 20 equivalent% or more of the total carboxyl groups;
d) a polyalkylene polyamine,
A polyamide polyamine obtained by polycondensation within a ratio of total amine equivalent to total carboxyl equivalent of 1.3: 1 to 3.0: 1, and
(3) The following physical properties after the amide exchange reaction i) Softening point of 80-190 ° C.
ii) Acid value of 0-5 mg KOH / g,
iii) an amine value of 10 to 100 mg KOH / g,
iv) The melt viscosity measured at 200 ° C. is 350 to 80,000 mPa · S, and v) The dissolution rate measured by immersing in 100 ml of acetic acid aqueous solution having a concentration of 30% by weight at 60 ° C. for 30 minutes is 0.2 mm / 30 minutes or more. A polyamide resin characterized by having: Claim 8 corresponds to this preferred embodiment, and is a method for producing the above three-dimensional injection molded circuit component, wherein the resin soluble in the low boiling point solvent is the above-mentioned polyamide (A) and polyamide polyamine (B). The present invention provides a method for producing a three-dimensional injection molded circuit component, which is a polyamide resin obtained by subjecting amide exchange reaction.

  Here, the dimer acid is a dimerized polymerized fatty acid which can be obtained by condensing unsaturated fatty acids such as oleic acid, linoleic acid and linolenic acid with a clay catalyst. The main component of dimer acid is dimer fatty acid (hereinafter referred to as dimer), and includes other monomers, trimers and the like. A method for producing dimer acid is described in, for example, US Pat. No. 3,157,681.

  The dimer acid that is a raw material of the polyamide resin has a dimer content of 65% by weight or more, and the dimer content is preferably 80% by overlap or more, particularly preferably 90 to 95% by weight. is there. Dimer acid can be used in the acid form, but can also be used as a derivative capable of forming an amide. An amide-forming derivative means a derivative that can react with a diamine component to form an amide bond. Such derivatives include esters of dimer acid, halides, and acid anhydrides.

  Examples of dicarboxylic acid components other than dimer acid include oxalic acid, malonic acid, adipic acid, succinic acid, suberic acid, sepacic acid, azelaic acid, pimelic acid, terephthalic acid, isophthalic acid, phthalic acid, naphthalene dicarboxylic acid, 1,4 -Or 1,3-cyclohexanedicarboxylic acid and the like and derivatives thereof capable of forming amides are exemplified.

  The content of the dimer acid or its amide-forming derivative in the dicarboxylic acid component is 20 equivalent% or more, preferably 50 equivalent% or more, more preferably 50 to 90 equivalent%, most preferably 55 to 50% of the total carboxyl groups. 85 equivalent%.

  Examples of the nitrogen-containing heterocyclic compound represented by the formula (I) or formula (II) include piperazine, 2,5-dimethylpiperazine, 2,5-diethylpiperazine, 2-methylpiperazine, 2-ethylpiperazine, N-amino. Ethyl-piperazine, N-aminopropyl-piperazine, 1.3-di (4-piperidyl) propane, 1,2-di (4-piperidyl) ethane, 1,4-di (4-piperidyl) butane, 1- ( N-pentahydroxyethyl-4-piperidyl) -3- (4-piperidyl) propane and the like are exemplified.

  Examples of the diamine compound other than the nitrogen-containing heterocyclic compound in the diamine component include ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,3-diaminobutane, tetramethylenediamine, pentamethylenediamine, and hexane. Methylenediamine, decamethylenediamine, octadecamethylenediamine, metaxylylenediamine, paraxylenediamine, cyclohexylenediamine, bis (aminoethyl) benzene, cyclohexylpis (methylamine), diamino-dicyclohexylmethane, methylenedianiline, Examples thereof include polyoxypropylene diamine and dimer diamine.

  The diamine component contains the nitrogen-containing heterocyclic compound in an amount of 20 equivalent% or more, preferably 20 to 90 equivalent%, more preferably 25 to 75 equivalent% of the total amino group.

  In the polyamide (A), the ratio of the total amine equivalent to the total carboxyl equivalent of the dicarboxylic acid component and the diamine component is 0.8: 1 to 1.3: 1, preferably 0.9: 1 to 1.2. Within the range of: 1, it can be obtained by polycondensation by heating. Examples of the heating conditions include a method of heating at 100 to 300 ° C. for about 3 to 10 hours. Heating may be performed under reduced pressure.

  Polyamide polyamine (B) is obtained by polycondensing the same dicarboxylic acid component and polyalkylene polyamine as described above within a ratio of the total amine equivalent to the total carboxyl equivalent of 1.3: 1 to 3.0: 1. can get. Examples of the polyalkylene polyamine include diethylenetriamine, triethylenetetramine, and tetraethylenepentamine. The polyamide polyamine (B) can be produced, for example, by a synthesis method described in Japanese Patent Publication No. 37-18898.

  The polyamide (A) and the polyamide polyamine (B) are usually melt-mixed at a high temperature of 150 to 300 ° C., preferably 200 to 250 ° C., usually for 1 hour or longer, preferably 5 hours or longer, more preferably 10 hours or longer. Thus, the polyamide resin is produced by an amide exchange reaction.

The polyamide resin thus obtained has the following physical properties after the amide exchange reaction.
i) Softening point of 80-190 ° C, preferably 120-180 ° C, more preferably 135-170 ° C,
ii) acid value of 0-5 mg KOH / g,
iii) an amine value of 10 to 100 mg KOH / g,
iv) a melt viscosity measured at 200 ° C. of 350 to 80,000 mPa · S, preferably 500 to 10,000 mPa · S, more preferably 1,000 to 8,000 mPa · S, and
v) It has a dissolution rate of 0.2 mm / 30 minutes or more, preferably 0.3 mm / 30 minutes or more, measured by immersing in 100 ml of 30% acetic acid aqueous solution at 60 ° C. for 30 minutes.

  As the resin soluble in the low-boiling solvent, a resin obtained by adding a filler such as aluminum hydroxide to the above resin can also be used.

  The present invention is a method for producing a three-dimensional injection molded circuit component comprising a step of subjecting a surface of a primary molded product to a surface other than a portion where a circuit is to be formed, and performing a secondary molding with a resin and eluting the secondary molded resin. In addition, a desired conductor circuit pattern can be formed with high accuracy, and the circuit pitch can be miniaturized. Further, it is not necessary to use a large amount of an organic solvent, and a large number of circuit components can be manufactured simultaneously.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a process diagram showing an example of the present invention. The example of FIG. 1 corresponds to the configuration of claim 1 of the present invention. First, a synthetic resin such as a liquid crystal polyester resin (LCP) plating grade is injection molded to obtain a primary molded product 1 (FIG. 1A). Next, an alkaline aqueous solution such as sodium hydroxide is heated to 50 to 90 ° C., and the surface is roughened by a method of immersing the primary molded product in the solution for about 1 to 60 minutes (FIG. 1B). ).

  After the surface roughening, a resin soluble in a low boiling point solvent such as IPA is injection-molded on the entire surface except the portion 2 where the circuit of the primary molded product is to be formed, and the resin layer 3 of the resin is formed. A secondary molded product is obtained (FIG. 1 (c)). The catalyst 4 is applied (including catalyst activation) to the portion 2 where the circuit of the secondary molded product thus obtained is to be formed (FIG. 1 (d)), and then the resin layer 3 Dissolution and removal are performed (FIG. 1 (e)).

  The resin layer 3 is dissolved and removed by IPA using a steam cleaning device. FIG. 2 is a conceptual diagram showing a steam cleaning apparatus used here. An IPA tank 5 is provided at the lower part of the steam cleaning apparatus, and a cooling pipe 10 is provided at the upper part for condensing the IPA vapor and returning it to the apparatus as droplets. The secondary molded product 7 is put in a barrel 8 provided between the IPA tank 5 and the cooling pipe 10.

  The barrel 8 is a cage formed by a net having an eye smaller than that of the secondary molded product 7, and holds the secondary molded product 7 and allows IPA vapor and droplets to pass through easily. The barrel 8 is provided on the rotating shaft of the motor 9 and is rotated by the motor 9, and the secondary molded product 7 in the barrel 8 is agitated by the rotation of the barrel 8.

  The IPA in the IPA tank 5 is heated by the heater 6 to become IPA vapor. The IPA vapor is condensed by the cooling pipe 10 and falls into the apparatus. The secondary molded product 7 in the barrel 8 comes into contact with the IPA vapor and droplets, and the resin layer 3 is dissolved and removed.

  By dissolving and removing the resin layer 3, a secondary molded product having the catalyst 4 in the portion 2 where a circuit is to be formed is obtained (FIG. 1 (e)). Electroless plating and further electroplating are performed on the catalyst 4 to form a plating layer 11, that is, a conductor circuit (FIG. 1 (f)), and a three-dimensional injection molded circuit component is obtained.

  FIG. 3 is a process diagram showing another example of the present invention. The example of FIG. 3 corresponds to the configuration of claim 2 of the present invention. First, a step of obtaining the primary molded product 1 (FIG. 3A), a step of roughening the surface of the primary molded product (FIG. 3B), and a circuit of the primary molded product after roughening. A step of obtaining a secondary molded product by injection molding a resin soluble in a low-boiling solvent such as IPA over the entire surface except the portion 2 to be formed (FIG. 3 (c) )) Is the same as the example of FIG. Further, also in the example of FIG. 3, the application of the catalyst 4 (including the activation of the catalyst) is performed on the portion 2 where the circuit of the secondary molded product thus obtained is to be formed (FIG. 3). 3 (d)).

  In the example of FIG. 3, after application of the catalyst 4, plating is performed on the portion 2 where a circuit is to be formed, and a plating layer 12 is formed (FIG. 3E). The plating layer 12 is formed by, for example, electroless plating and subsequent electroplating, as in the example of FIG. 1, and after the plating layer 12 is formed, the resin layer 3 is dissolved and removed (see FIG. 1). 3 (f)), a three-dimensional injection molded circuit component is obtained. The resin layer 3 is dissolved and removed by IPA using a steam cleaning device, as in the example of FIG. The steam cleaning apparatus used is the same as that in the example of FIG. As another embodiment, a method of performing electroplating after dissolving and removing the resin layer 3 after performing electroless plating can also be adopted.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, the scope of the present invention is not limited by an Example.

Example 1
(Molding of primary molded product, roughening)
Liquid crystal polyester resin (LCP) [trade name: Vectra C810, manufactured by Polyplastics Co., Ltd.] was used to maintain an injection pressure of 50 kg / cm ² using an injection molding machine (clamping force = 100 tons, screw diameter = 45 mmφ). A rectangular primary molded product having a length and width of about 4 mm and a thickness of about 1.5 mm was obtained by injection molding under conditions of a mold temperature of 60 ° C. for a pressure time of 10 seconds. The obtained primary molded product was washed with ethanol, then immersed in a 45% aqueous sodium hydroxide solution set at 80 ° C. for 5 minutes, and then roughened by neutralizing with 3% hydrochloric acid.

(Molding of secondary molded products)
Set the rough molded primary molded product in the secondary mold and injection-mold a resin soluble in the following low-boiling solvents (hereinafter referred to as resist resin) to form the circuit of the primary molded product. A resin layer was formed on the entire surface excluding the power portion to obtain a secondary molded product. FIG. 4 shows a plan view and a side view of circuit patterns of the three-dimensional injection molded circuit components obtained in the examples and comparative examples. As shown in FIG. 4, in the circuit pattern, L / S = 300/300.

  The resist resin used was obtained by polycondensation of dimer acid (0.65 equivalent), sebacic acid (0.35 equivalent), ethylenediamine (0.53 equivalent), and piperazine (0.53 equivalent). Polyamide (A) having a softening point of 160 ° C., an acid value of 1.0 mgKOH / g, an amine value of 10.0 mgKOH / g, a melt viscosity of 3000 mPa · S (210 ° C.), dimer acid (1.0 equivalent) and diethylenetriamine (1. 5 equivalents), polyamidopolyamine (B) having an acid value of 1.0 mgKOH / g, an amine value of 100.0 mgKOH / g, and a melt viscosity of 100 mPa · S (200 ° C.), A: B = Blended at a weight ratio of 80/20, melt-mixed at 230 ° C. for 12 hours, and obtained by amide exchange reaction, softening point 150 ° C., acid value 1.0 mgKOH / g, amine value 25 Polyamide resin of 0 mg KOH / g, melt viscosity 3000 mPa · S (200 ° C.), dissolution rate with respect to organic acid 0.3 mm / 30 minutes, filler of aluminum hydroxide (made by Showa Denko, trade name: Hygilite H-42, average What dispersed 20 volume% of the particle size 1.1 micrometer) was used.

(Degreasing, surface adjustment)
A processing solution obtained by dissolving 40 g / L of A-screen A-220 (trade name, manufactured by Okuno Pharmaceutical Co., Ltd.) in pure water was set at 45 ° C., and the obtained secondary molded product (sample) was placed in the processing solution for 15 minutes. After soaking, it was further immersed in hot water at 45 ° C. for 5 minutes, and then thoroughly washed with ion-exchanged water and degreased.

  A treatment solution in which 100 ml / L of conditioner 3320 (product name of Shipley) was added to pure water was set at 45 ° C., and the degreased sample was immersed in the treatment solution for 15 minutes, and then thoroughly washed with ion-exchanged water. The surface was adjusted. Note that this step is preferably performed under reduced pressure in order to ensure that the processing liquid penetrates into the resist groove portion serving as the conductor forming portion, and was also performed under reduced pressure in this example.

(Pre-dip)
Sodium chloride (180 g / L), hydrochloric acid (80 ml / L), and OS-1505 [manufactured by Shipley Far East Co., Ltd., trade names: hydrochloric acid (16%), urea (22%) and D-sorbitol (10%) The aqueous solution] (20 ml / L) was mixed in the same volume to prepare a treatment liquid. The treatment liquid was set at a temperature of 45 ° C., and the surface-adjusted sample was immersed in it for 3 minutes. , Did a pre-dip.

(Catalyst application, catalyst activation)
Sodium chloride (180 g / L), hydrochloric acid (100 ml / L), OS-1505 [manufactured by Shipley Far East Co., Ltd., trade name] (20 ml / L), and OS-1558 [manufactured by Shipley Far East Co., Ltd.] , Trade name: Palladium chloride aqueous solution containing hydrochloric acid (12%) and cuprous chloride (12%)] (20 ml / L) were mixed in the same volume to prepare a treatment solution. The sample that had been pre-dipped therein was immersed for 8 minutes, and then the sample was washed with ion-exchanged water to give a catalyst.

  After the catalyst was applied, a treatment solution consisting of OS-1560 [manufactured by Shipley Far East, trade name: aqueous solution of sulfuric acid (30%) and borohydrofluoric acid (15%)] (20 ml / L) The temperature was set to 0 ° C., the sample was immersed in this treatment solution for 2 minutes to activate the catalyst, and then the sample was washed with ion-exchanged water.

(Resolution and removal of resist resin)
In the steam cleaning apparatus shown in FIG. 2, the secondary molded product to which the catalyst was applied and the catalyst was activated was put, and contacted with the IPA vapor and droplets for 30 minutes to dissolve and remove the resist resin. Thereafter, in order to remove the filler dispersed in the remaining resist resin, ultrasonic cleaning was performed in pure water for 5 minutes.

(Acid activity)
The obtained sample was immersed in a 50 ml / L sulfuric acid aqueous solution set at 45 ° C. for 2 minutes, and then sufficiently washed with ion-exchanged water.

(Electroless copper plating)
OS-1598M (48 ml / L), OS-1598A (10 ml / L), OS-1598R (2 ml / L), OS-1120SR (2.1 ml / L), CupZ (23 ml / L), and CupY (12 ml / L) L) [each electroless copper plating solution manufactured by Shipley Far East Co., Ltd., trade name] are mixed to prepare a plating solution, and then the plating solution is set to a temperature of 45 ° C., The sample was immersed in it for 15 minutes, and electroless copper plating was performed. After immersion, the sample was washed with ion exchange water.

(Electro copper plating)
The water-washed sample was subjected to an acid activation treatment in the same manner as described above, and then subjected to electrolytic copper plating. That is, the same volume of copper sulfate (220 g / L) and sulfuric acid (60 g / L) were mixed to prepare a plating solution, and then the plating solution was set at a temperature of 25 ° C. and the sample was immersed therein. By energizing for 20 minutes at a current density of ² A / dm ² , a plating layer having a thickness of about 15 μm was formed to obtain a three-dimensional injection molded circuit component.

  In the step after the secondary molding (for example, dissolution and removal of resist resin), 1000 samples (secondary molded products) were processed at a time. The same applies to the following comparative examples. Moreover, as a method of electroless copper plating and electrolytic copper plating, a barrel plating method was used in which a sample was placed in a rotating basket and plating was performed while rotating the basket. This method is effective when the secondary molded product is small. Further, in order to improve the movement between samples and to efficiently stir the plating solution, the plating solution was blown into the barrel. Thereby, the bridge | bridging of circuits by abnormal precipitation and the dispersion | variation in quality can be suppressed.

  Through the above process, the intended three-dimensional circuit could be formed. The appearance yield was 95%. The IPA required for dissolving and removing the resist resin layer was 1 L, and the same operation could be repeated five times with the same solution.

Comparative Example 1
The molding of the primary molded product, roughening, molding of the secondary molded product, degreasing, surface adjustment, pre-dip and catalyst application, and catalyst activation were performed in the same manner as in Example 1. Thereafter, the resist resin was dissolved and removed by immersing the sample in 3 L of IPA heated to 80 ° C. for 30 minutes with stirring. Since re-adhesion of the dissolved resist resin component was observed, the same treatment was repeated two more times. Thereafter, ultrasonic cleaning was performed for 5 minutes in the same manner as in Example 1, and then acid activity, electroless copper plating and electrolytic copper plating were performed in the same manner as in Example 1 to obtain a three-dimensional injection molded circuit component.

  The yield was 70%. Most of the defects were resist residues and missing circuits. It is presumed that the reason for the frequent occurrence of defects is that the treatment time is long and palladium is dropped due to excessive stirring. The IPA required for dissolving and removing the resist resin layer was 9 L, and the processing time was 120 minutes.

Comparative Example 2
The molding of the primary molded product, roughening, molding of the secondary molded product, degreasing, surface adjustment, pre-dip and catalyst application, and catalyst activation were performed in the same manner as in Example 1. Thereafter, the resist resin was dissolved and removed by immersing the sample for 30 minutes while stirring in 3 L of 30% by weight acetic acid heated to 75 ° C. Since re-adhesion of the dissolved resist resin component was observed, the same treatment was repeated two more times. Thereafter, ultrasonic cleaning was performed for 5 minutes in the same manner as in Example 1, and then acid activity, electroless copper plating and electrolytic copper plating were performed in the same manner as in Example 1 to obtain a three-dimensional injection molded circuit component.

  The obtained three-dimensional injection-molded circuit component had poor plating depositability, a circuit could not be drawn according to the pattern of the resist, and the yield was 10%. The cause is presumed that palladium was dissolved in the acid in the resist removal step.

Comparative Example 3
The molding of the primary molded product, roughening, molding of the secondary molded product, degreasing, surface adjustment, pre-dip and catalyst application, and catalyst activation were performed in the same manner as in Example 1. Thereafter, acid activity and electroless copper plating were performed in the same manner as in Example 1. After electroless copper plating, the resist resin was dissolved and removed in the same manner as in Comparative Example 1. Since re-adhesion of the dissolved resist resin component was observed, the same treatment was repeated two more times. Thereafter, ultrasonic cleaning was performed for 5 minutes in the same manner as in Example 1, and then an acid activation treatment was performed under the same conditions as in Example 1. Further, electrolytic copper plating was performed under the same conditions as in Example 1, and three-dimensional An injection molded circuit component was obtained.

  The yield was 50%. The content of the defect is that the circuit becomes thinner toward the rising edge of the circuit. In the electroless copper plating process, since the aspect ratio of the resist groove is large, the supply of copper ions is delayed particularly at the circuit rising portion, and the plating cannot be sufficiently grown. Moreover, the non-defective product also had a relatively large variation in circuit L / S. It is presumed that the copper plating deposited on the resist is torn off.

  As a result of the above examples and comparative examples, the method of the present invention makes it possible to accurately form a desired conductor circuit pattern, and it is not necessary to use a large amount of an organic solvent. It also shows that it can be manufactured at the same time.

It is process drawing which shows an example of this invention. It is a conceptual diagram which shows the steam cleaning apparatus used for implementation of this invention. It is process drawing which shows another example of this invention. It is the (A) top view and (B) side view of the circuit pattern of an Example and a comparative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Primary molded product 2 The part which should form a circuit 3 Resin layer 4 Catalyst 5 IPA tank 6 Heater 7 Secondary molded product 8 Barrel 9 Motor 10 Cooling pipe 11, 12 Plating layer

Claims (8)

  A step of obtaining a secondary molded product by forming a resin layer made of a resin soluble in a low boiling point solvent on a surface other than a portion where a circuit is to be formed of a primary molded product constituting a circuit component substrate; A step of applying a catalyst to a portion of the surface of the molded product where a circuit is to be formed; after applying the catalyst, the secondary molded product is brought into contact with the low boiling solvent vapor and / or the low boiling solvent droplets; A three-dimensional injection molded circuit component comprising: a step of dissolving and removing the resin layer; and a step of forming a conductive circuit layer by electroless plating on the catalyst-applied portion after the resin layer is dissolved and removed. Production method.   A step of obtaining a secondary molded product by forming a resin layer made of a resin soluble in a low boiling point solvent on a surface other than a portion where a circuit is to be formed of a primary molded product constituting a circuit component substrate; A step of applying a catalyst to a portion of the surface of the molded product where the circuit is to be formed, a step of applying electroless plating to the portion of the secondary molded product where the circuit is to be formed, and a step of applying electroless plating. Then, the secondary molded article is brought into contact with the low boiling point solvent vapor and / or the low boiling point solvent droplets to dissolve and remove the resin layer, and the three-dimensional injection molding Circuit component manufacturing method.   Holding the secondary molded product in a container through which the low-boiling solvent vapor and droplets can pass through contact between the secondary molded product and the low-boiling solvent vapor and / or low-boiling solvent droplets; The method for producing a three-dimensional injection molded circuit component according to claim 1 or 2, wherein the container is agitated or vibrated.   4. The method for manufacturing a three-dimensional injection molded circuit component according to claim 1, wherein the primary molded product is formed by injection molding of a synthetic resin.   The method for producing a three-dimensional injection molded circuit component according to any one of claims 1 to 4, wherein the resin layer is formed after the surface of the primary molded product is roughened.   6. The production of a three-dimensional injection molded circuit component according to claim 1, wherein the resin layer made of a resin soluble in a low boiling point solvent is formed by injection molding of the resin. Method.   The method for producing a three-dimensional injection molded circuit component according to any one of claims 1 to 6, wherein the low boiling point solvent is isopropyl alcohol. The resin soluble in the low boiling point solvent is a polyamide resin obtained by subjecting polyamide (A) and polyamide polyamine (B) to an amide exchange reaction,
(1) Polyamide (A)
a) a dicarboxylic acid component containing a dimer acid having a dimer content of 65% by weight or more or an amide-forming derivative thereof in an amount of 20 equivalent% or more of the total carboxyl groups;
b) The following formula (I)

[Wherein, R ¹ is independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and Y is a hydrogen atom, RNH ₂ or ROH (R is an alkylene group having 1 to 6 carbon atoms). It is. A piperazine compound represented by formula (II):

[Wherein, R ¹ is independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R ² is a divalent aliphatic hydrocarbon group, and Y is a hydrogen atom, RNH ₂ or ROH ( R is an alkylene group having 1 to 6 carbon atoms. A diamine component containing at least one nitrogen-containing heterocyclic compound selected from the group consisting of the dipiveridyl compounds represented by the formula:
A polyamide obtained by polycondensation within a ratio of total amine equivalent to total carboxyl equivalent of 0.8: 1 to 1.3: 1,
(2) Polyamide polyamine (B)
c) a dicarboxylic acid component containing a dimer acid having a dimer content of 65% by weight or more or an amide-forming derivative thereof in an amount of 20 equivalent% or more of the total carboxyl groups;
d) a polyalkylene polyamine,
A polyamide polyamine obtained by polycondensation within a ratio of total amine equivalent to total carboxyl equivalent of 1.3: 1 to 3.0: 1, and
(3) The following physical properties after the amide exchange reaction i) Softening point of 80-190 ° C,
ii) Acid value of 0-5 mg KOH / g,
iii) an amine value of 10 to 100 mg KOH / g,
iv) The melt viscosity measured at 200 ° C. is 350 to 80,000 mPa · S, and v) The dissolution rate measured by immersing in 100 ml of acetic acid aqueous solution with a concentration of 30% by weight at 60 ° C. for 30 minutes is 0.2 mm / 30 minutes or more. The method for manufacturing a three-dimensional injection molded circuit component according to any one of claims 1 to 7, wherein:

Images