JP2003115645A - Three-dimensional circuit board - Google Patents

Abstract

(57) [Problem] A three-dimensional circuit such as an antenna having a small voltage standing wave ratio (VSWR) and a small warpage or deformation due to a change in temperature or humidity and suitable for being incorporated into a mobile communication device such as a mobile phone. Provide a substrate. SOLUTION: A thermoplastic resin composition having a dielectric loss tangent of 0.01 or less at 1 kHz to 20 GHz, an IZOD impact strength of 2 kJ / m or more, and a heat deformation temperature of 110 ° C. or more under a load of 18.6 kgf is formed into a predetermined shape. A mask is formed on the substrate so that a surface portion of the surface of the substrate where the conductor layer is to be formed is exposed, and a mask is formed on the substrate so as to cover other surface portions, and the mask is exposed from the mask. Etching the surface of the substrate, applying a catalyst for electroless plating to the etched surface, removing the mask from the substrate, and then forming a conductor layer of a predetermined pattern on the surface of the substrate by electroless plating. To obtain a three-dimensional circuit board.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional circuit board, and more particularly, it has a small voltage standing wave ratio (VSWR) and little warpage or deformation due to changes in temperature or humidity.
The present invention relates to a three-dimensional circuit board such as an antenna suitable for incorporation in mobile communication devices such as mobile phones.

[0002]

2. Description of the Related Art Mobile communication devices such as mobile phones and GPS
A three-dimensional circuit board such as a dielectric antenna used in a (Global Positioning System) device or the like is required to have a small size by its nature. A three-dimensional circuit board such as a dielectric antenna is one in which a radiation conductor layer and a ground conductor layer are provided on both surfaces of a substrate made of a dielectric material having a predetermined shape (for example, a plate shape). Conventionally, ceramics have been used as the dielectric material. Ceramics have problems that it is difficult to process them into arbitrary shapes, they are heavy, and they are difficult to dispose of. Recently, resins have been used.

As the resin used for the three-dimensional circuit board,
Thermoplastic aromatic polyester resin, polyphenylene sulfide resin, syndiotactic polystyrene resin,
Polyphenylene ether resin, polyetherimide resin, polycarbonate resin, polyacetal resin, polysulfone resin, polyether sulfone resin, polyamideimide resin, polyarylate resin, thermoplastic resin such as 5-methylpentene resin, epoxy resin, phenol resin, Thermosetting resins such as unsaturated polyester resins and polyether ether ketone resins have been proposed. Among these, the dielectric loss tangent at 10 GHz is 0.006 or less,
An electronic component using a substrate formed of a material mainly composed of syndiotactic polystyrene having a melting point of 240 ° C. or higher, a specific gravity of 1.5 or lower, and a relative crystallinity of 50% or higher has been proposed (special feature: (Kai 2000-40421). Further, a molding comprising 100 parts by weight of a thermoplastic norbornene resin and 1 to 40 parts by weight of a soft polymer, having a dielectric loss tangent of 0.0015 or less at 1 kHz to 20 GHz and an IZOD impact strength of 5 kg · cm / cm or more. It has also been proposed to mold the material and use it as an insulating plate of a microstrip antenna (Japanese Patent Laid-Open No. 8-325440). However, in these conventional circuit boards, the VSWR value in the high frequency range of 2 GHz is not low, the peak gain is not sufficient, and warpage and deformation due to changes in temperature and humidity easily occur, so that the resonance frequency changes depending on environmental changes. There was a big change.

[0004]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a mobile communication device such as a mobile phone, which has a small voltage standing wave ratio (VSWR) even in a high frequency range and has little warpage or deformation due to temperature and humidity changes. Antenna suitable for installation
To provide a three-dimensional circuit board such as.
The present inventors have conducted extensive studies to achieve the above object, and as a result, formed of a thermoplastic resin composition having a dielectric loss tangent of a specific value or less, an IZOD impact strength of a specific value or less, and a heat distortion temperature of a specific value or more. It has been found that the object of the present invention can be achieved by providing a conductor layer on the surface of the substrate and using a three-dimensional circuit board in which the surface glossiness Gs of the conductor layer is a specific value or more, and the present invention has been completed based on this finding. Came to do.

[0005]

According to the present invention, the dielectric loss tangent at 1 kHz to 20 GHz is 0.01 or less, the IZOD impact strength is 2 kJ / m or more, and 18.6.
A three-dimensional circuit board in which a conductor layer is provided on the surface of a substrate formed of a thermoplastic resin composition having a heat distortion temperature of 110 ° C. or more under a load of kgf, and the surface gloss Gs (60 degrees) of the conductor layer is 50 or more. Will be provided.

Further, according to the present invention, 1 kHz to 20 G
A step of forming a thermoplastic resin composition having a dielectric loss tangent at 0.01 or less, an IZOD impact strength of 2 kJ / m or more, and a heat deformation temperature of 110 ° C. or more under a load of 18.6 kgf on a substrate having a predetermined shape, Forming a mask on the substrate so as to expose a surface portion on which a conductor layer is to be formed and cover the other surface portion of the surface of the substrate;
Etching the surface of the mask and the surface of the substrate exposed from the mask, applying a catalyst for electroless plating to the etched surface, removing the mask from the substrate, removing the mask There is provided a method for manufacturing a three-dimensional circuit board including a step of forming a conductor layer having a predetermined pattern on the surface of the board by electroless plating.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The three-dimensional circuit board of the present invention is 1 kH.
Dielectric loss tangent at z to 20 GHz is 0.01 or less, IZOD
A conductor layer is provided on the surface of a substrate formed of a thermoplastic resin composition having an impact strength of 2 kJ / m or more and a heat deformation temperature of 110 ° C. or more under a load of 18.6 kgf, and the surface glossiness Gs ( 60 degrees) is 50 or more.

The thermoplastic resin composition used in the present invention has a dielectric loss tangent of 0.01 or less at 1 kHz to 20 GHz, an IZOD impact strength of 2 kJ / m or more, and a heat deformation temperature under a load of 18.6 kgf. Is 110 ° C. or higher.

The dielectric loss tangent of the thermoplastic resin composition is preferably 0.002 or less, and particularly preferably 0.001 or less. Here, the dielectric loss tangent is 0.01 or less in the entire frequency region of 1 kHz to 20 GHz. The dielectric loss tangent is a value measured according to JIS K 6911. If the dielectric loss tangent is large, the electric signal loss may be large. The IZOD impact strength of the thermoplastic resin composition is preferably 5 kJ / m or more, particularly preferably 1
It is 0 kJ / m or more. IZOD impact strength is JIS K
It is a value measured in accordance with 7110. See also 18.6
The heat distortion temperature under load of kgf is preferably 120 ° C.
Above, especially preferably above 130 ° C. The heat distortion temperature is a value measured according to JIS K 7206.

Examples of the thermoplastic resin composition having such characteristics include those composed of a thermoplastic resin and a rubber elastic body. Suitable thermoplastic resins include
Amorphous thermoplastic resins are mentioned, and specific examples thereof include addition polymers of norbornene-based monomers and olefins, addition polymers of norbornene-based monomers, ring-opening polymers of norbornene-based monomers and hydrogens thereof. Hydrogenated aromatic ring portion of polymer of aromatic vinyl monomer, hydrogenated aromatic ring portion of random or block copolymer of aromatic vinyl monomer and conjugated diene monomer Examples of the known amorphous resin include polymers of alicyclic vinyl monomers. The norbornene-based monomer is a polycyclic unsaturated hydrocarbon such as norbornene, dicyclopentadiene or tetracyclododecene obtained by an addition reaction of cyclopentadiene and an olefin, and an alkyl-substituted product thereof; It refers to a polycyclic unsaturated hydrocarbon derivative such as a polar group-substituted product such as a group, an acid anhydride group, an epoxy group, an amide group, and an ester group.

Specific examples of the rubber elastic body include natural rubber,
Polybutadiene, polyisoprene, polyisobutylene,
Neoprene, polysulfide rubber, thiochol rubber, acrylic rubber, urethane rubber, silicone rubber, epichlorohydrin rubber, styrene-butadiene block copolymer, hydrogenated styrene-butadiene block copolymer (SEB), styrene-butadiene-styrene block copolymer Combined (SBS), hydrogenated styrene-butadiene-
Styrene block copolymer (SEBS), styrene-isoprene block copolymer, hydrogenated styrene-isoprene block copolymer (SEP), styrene-isoprene-styrene block copolymer (SIS), hydrogenated styrene-isoprene-styrene Block copolymer (SE
PS), or ethylene propylene rubber (EPM), ethylene propylene diene rubber (EPDM), ethylene-
Butene copolymer, ethylene-octene copolymer, olefin rubber such as linear low-density polyethylene elastomer, or butadiene-acrylonitrile-styrene-core shell rubber (ABS), methyl methacrylate-
Butadiene-styrene-core shell rubber (MBS), methyl methacrylate-butyl acrylate-styrene-
Core shell rubber (MAS), octyl acrylate-butadiene-styrene-core shell rubber (MABS), alkyl acrylate-butadiene-acrylonitrile-
Styrene-core shell rubber (AABS), butadiene-
Core-shell type particulate elastic body such as styrene-core shell rubber, siloxane-containing core shell rubber such as methyl methacrylate-butyl acrylate-siloxane,
Alternatively, rubbers obtained by modifying these may be used. Among these rubber elastic materials, in the present invention, styrene-ethylene-butylene-styrene block copolymer (SEBS) and styrene-ethylene-propylene-styrene block copolymer (SEPS) are used in view of heat resistance and dielectric properties.
Is preferred.

When the above-mentioned amorphous thermoplastic resin is used as the thermoplastic resin, another resin can be contained in the resin composition. Other resins that can be contained in the resin composition include linear high-density polyethylene, linear low-density polyethylene, high-pressure low-density polyethylene, isotactic polypropylene, syndiotactic polypropylene, block polypropylene, random polypropylene. , Polybutene, 1,2-polybutadiene, 4-methylpentene, cyclic polyolefins and polyolefin resins represented by copolymers thereof, atactic polystyrene, isotactic polystyrene, syndiotactic polystyrene, HIPS, AB
S, AS, styrene-methacrylic acid copolymer, styrene-methacrylic acid alkyl ester copolymer, styrene-
Methacrylic acid glycidyl ester copolymer, styrene-
Acrylic acid copolymer, styrene-acrylic acid alkyl ester copolymer, styrene-maleic acid copolymer, styrene-polystyrene resin represented by fumaric acid copolymer, polycarbonate, polyethylene terephthalate,
Polyester resin typified by polybutylene terephthalate, polyamide resin typified by nylon 6, nylon 6,6, polyphenylene ether, polyarylene sulfide, poly-4-fluoroethylene (PTFE)
And other fluorinated polyethylene resins. Among these, polyolefins such as polyethylene and polypropylene or polyphenylene ethers are preferable.

The resin composition may contain one kind or a combination of two or more kinds of fibrous or particulate dielectric ceramics having a small dielectric loss tangent. By including such a dielectric ceramic, the dielectric constant of the substrate can be adjusted to a desired value. The dielectric ceramics that can be contained in the resin composition,
Barium titanate, strontium titanate, calcium titanate, barium strontium titanate, a complex of amorphous titanium oxide and an alkaline earth metal titanate, lead zirconate titanate; calcium silicate such as wollastonite and zonotolite; Magnesium borate,
Aluminum borate, zinc silicate, etc. can be mentioned.

For the purpose of improving mechanical properties such as strength, it is desirable to include an inorganic filler. The shape of the inorganic filler is not particularly limited, and any of fibrous, granular, and powder forms can be used. As the fibrous filler, for example,
Examples thereof include glass fiber and carbon fiber. Examples of the shape include a cloth shape, a mat shape, a bundle cutting shape, a short fiber, a filament shape, and a whisker. As the granular or powdery filler, talc, carbon black, graphite, titanium dioxide, silica, mica, calcium carbonate,
Calcium sulfate, barium carbonate, magnesium carbonate, magnesium sulfate, barium sulfate, oxysulfate,
Examples thereof include tin oxide, alumina, kaolin, silicon carbide, metal powder, glass powder, glass flakes and glass beads. Among the above fillers, particularly glass fillers such as glass powder, glass flakes, glass beads, glass filaments, glass fibers,
Glass lobing and glass mat are preferred. In addition, surface-treated materials may be used as these fillers.
The coupling agent used in the surface treatment is used to improve the adhesiveness between the filler and the thermoplastic resin, so-called silane coupling agents, titanium coupling agents, etc. Any one can be selected and used from the inside.

The resin composition used in the present invention may contain various additives exemplified below, as long as the object of the present invention is not impaired. Examples of the additives include anti-blocking agents, antioxidants, nucleating agents, antistatic agents, process oils, plasticizers, release agents, compatibilizers, flame retardants, flame retardant aids, pigments and the like. it can.

Inorganic particles or organic particles are used as the anti-blocking agent. Inorganic particles (Note: some of them may overlap with the dielectric ceramics and inorganic filler)
I such as lithium fluoride, borax (sodium borate hydrate)
Group A element compounds, magnesium carbonate, magnesium phosphate, magnesium oxide (magnesia), magnesium chloride, magnesium acetate, magnesium fluoride, magnesium titanate, magnesium silicate, magnesium silicate hydrous salt (talc), calcium carbonate, calcium phosphate, phosphorous acid Calcium, calcium sulfate (gypsum), calcium acetate, calcium terephthalate, calcium hydroxide, calcium silicate, calcium fluoride, calcium titanate, strontium titanate, barium carbonate, barium phosphate,
Group IIA element compounds such as barium sulfate and barium sulfite,
Group IVA element compounds such as titanium dioxide (titania), titanium monoxide, titanium nitride, zirconium dioxide (zirconia), zirconium monoxide, etc., Group VIA element compounds such as molybdenum dioxide, molybdenum trioxide, molybdenum sulfide, etc.,
Group VIIA element compounds such as manganese chloride and manganese acetate,
Group VIII element compounds such as cobalt chloride and cobalt acetate, Group IB element compounds such as cuprous iodide, Group IIB element compounds such as zinc oxide and zinc acetate, aluminum oxide (alumina),
II such as aluminum hydroxide, aluminum fluoride, alumina silicate (alumina silicate, kaolin, kaolinite)
Group IB element compounds, silicon oxide (silica, silica gel),
Examples include IVB group element compounds such as graphite, carbon, graphite and glass, and particles of natural minerals such as carnal stone, kainite, mica (mica, quinnemo), and birose ore. As the organic particles, fluorinated polyethylene resin,
Examples thereof include melamine resins, styrene / divinylbenzene copolymers, acrylic resins and crosslinked products thereof.

The antioxidant can be arbitrarily selected from known antioxidants such as phosphorus-based, phenol-based and sulfur-based antioxidants, preferably phenol-based antioxidants. By using the antioxidant, the surface glossiness is increased and the shape change due to the use environment is reduced. As a nucleating agent, a metal salt of carboxylic acid such as aluminum di (pt-butylbenzoate), methylenebis (2,2)
Examples thereof include metal salts of phosphoric acid such as sodium 4-di-t-butylphenol) acid phosphate, talc, and phthalocyanine derivatives. As the plasticizer, polyethylene glycol, polyamide oligomer, ethylenebisstearamide, phthalic acid ester, polystyrene oligomer, polyethylene wax and the like can be arbitrarily selected and used.

The release agent may be arbitrarily selected from known materials such as polyethylene wax, silicone oil, long-chain carboxylic acid, and long-chain carboxylic acid metal salt. Process oils are roughly classified into paraffin oils, naphthene oils, and aroma oils according to the type of oil, but paraffin oils are preferred. As the viscosity of the process oil, the kinematic viscosity at 40 ° C. is 15 to 600.
cSt is preferable, and 15 to 500 cSt is more preferable. The compatibilizer may be added in order to improve the affinity between the thermoplastic resin and the rubber elastic body or the like to effectively compatibilize it, and also to improve the affinity between the thermoplastic resin and the filler. it can. Specifically, a polymer having compatibility or affinity with a thermoplastic resin can be mentioned.

The proportion of each component in the resin composition is preferably 35 to 98% by weight of the thermoplastic resin, more preferably 50 to 95% by weight, and particularly preferably 70 to 90% by weight. The total amount of other resins and additives is preferably 65 to 2% by weight, more preferably 50 to 5% by weight, and particularly preferably 30 to 10% by weight.

The resin composition used in the present invention is obtained by mixing the above-mentioned components, and the mixing method is not particularly limited. For example, the resin composition is blended and melt-kneaded at any stage of the thermoplastic resin production process. Various methods such as a method and a method of blending each component constituting the composition and melt-kneading may be used.

The substrate is obtained by molding the resin composition. The molding method is not particularly limited, and examples thereof include an injection molding method, a press molding method, an extrusion molding method, and a cast molding method. The substrate may have various shapes such as a sheet shape, a plate shape, a box shape, a round bar shape, and a rectangular bar shape, depending on the installation location of the three-dimensional circuit board.

The conductor layer used in the present invention is formed of a layer of a conductive material such as metal. Examples of the conductive material include conductive metals such as copper, aluminum, silver and gold, IT
Examples thereof include conductive oxides such as O (indium tin oxide). Of these, gold, silver and copper are preferable. In the three-dimensional circuit board of the present invention, the surface glossiness Gs (60 degrees) of the conductor layer is 50 or more, preferably 80 or more,
It is particularly preferably 100 or more. When the surface glossiness is low, the value of the voltage standing wave ratio is high and the peak gain is low. When the three-dimensional circuit board is used as an antenna, a radiation conductor layer and a ground conductor layer are provided as conductor layers, and they are usually short-circuited.

As a method of forming the conductor layer, a method of plating a substrate obtained by molding the resin composition, or a so-called insert molding method of arranging and molding a metal plate or the like when molding the resin composition Is mentioned. The method for manufacturing a three-dimensional circuit board according to the present invention has a dielectric loss tangent at 1 kHz to 20 GHz of 0.01 or less, an IZOD impact strength of 2 kJ / m or more,
And the heat distortion temperature under load of 18.6kgf is 110 ℃.
The step of forming the thermoplastic resin composition on a substrate having a predetermined shape as described above, and masking the substrate so as to expose the surface portion of the substrate on which the conductor layer is to be formed and cover the other surface portion. Forming the surface of the mask, etching the surface of the mask and the surface of the substrate exposed from the mask, applying a catalyst for electroless plating to the etched surface, and removing the mask from the substrate And a step of forming a conductor layer having a predetermined pattern on the surface of the substrate from which the mask has been removed by electroless plating. By this manufacturing method, it is possible to form the conductor layer having the high surface gloss as described above.

The production method of the present invention will be described with reference to specific embodiments. First, in the first step, the thermoplastic resin composition is charged into an injection molding machine, and the thermoplastic composition is injected into the cavity with the mold closed to mold the composition. A cubic substrate having a predetermined shape is formed by injection molding. Next, the second step is to form a mask on the substrate so as to expose a surface portion of the surface of the substrate on which a conductor layer having a predetermined pattern is to be formed and cover the other surface portion. . The material for the mask is preferably an elastomer that exhibits elasticity at room temperature and can be easily bent,
Particularly preferably, it exhibits weak compatibility at the contact interface between the substrate and the mask, and maintains the adhesion strength to the extent that liquid does not enter. Specifically, a thermoplastic polyester elastomer such as "Hytrel # SB704" (trade name) manufactured by Toray DuPont, styrene-isoprene-styrene block copolymer, styrene-butadiene-styrene block copolymer, styrene. Examples thereof include thermoplastic polystyrene-based elastomers such as ethylene-butylene-styrene block copolymer.

The mask can be obtained, for example, by injection molding so as to cover the surface of the substrate, or by dissolving the mask material in a solvent, applying the solution, and drying.
In the third step, the mask and the surface of the substrate exposed from this mask are etched. As an example of this etching process, an alkaline aqueous solution in which caustic soda or caustic potash is dissolved in a predetermined concentration (for example, 45 wt%) is heated to a predetermined temperature (for example, 50 to 90 ° C.), and a substrate covered with a mask is heated for a predetermined time (for example). For example, a method of dipping the substrate for 30 minutes or a substrate covered with a mask in a mixed solution of chromic anhydride and concentrated sulfuric acid (50 to 90 ° C.) for about 3 to 20
A method of immersing for a minute may be used.

In the fourth step, an electroless plating catalyst is attached to the etched surface to form a catalyst application surface. For example, the substrate obtained in the third step is dipped in a catalyst solution containing tin and palladium, and then dipped in an acid such as hydrochloric acid and sulfuric acid to deposit palladium on the surface. Alternatively, a relatively strong reducing agent such as stannous chloride is adsorbed on the surface and then immersed in a catalyst solution containing a noble metal ion such as gold to deposit gold on the surface. The temperature of the catalyst solution is 15 to 23 ° C., and the immersion time is about 5 minutes. In this way, the catalyst is applied to the etched surface.

The fifth step is a step of drying the substrate immersed in the catalyst solution and then removing the mask from the substrate. This can be done manually, but mask removal equipment may be used to facilitate this removal operation. It should be noted that by selecting the material of the mask from those having a weak compatibility with the material of the substrate, the work of removing the mask becomes easy. Finally, in the sixth step, the substrate is electroless plated. By this step, the plated layer is formed only on the catalyst application surface, and the three-dimensional circuit board is obtained. The order of the fifth step and the sixth step may be reversed. That is, after the substrate immersed in the catalyst solution is dried, electroless plating is performed to form a plating layer on the unmasked portion, and then the mask is removed.

The three-dimensional circuit board of the present invention can be used for various purposes. For example, circuit boards, antennas, antenna terminals, coaxial connectors, high-frequency components such as connectors,
It can be used for a heating device such as a microwave oven using a high frequency. Of these, application to an antenna, particularly application to a built-in antenna such as a mobile phone, PHS, and Bluetooth is suitable. Other antennas such as inverted F antennas for base stations, flat antennas, patch antennas, satellite parabola antennas, GPS antennas, satellites for sanitary communication, Cassegrain antennas, etc.
An antenna for C, an antenna for ITS, etc. are mentioned. Furthermore, it can be applied to a dielectric lens or the like that converts the wavefront of a radio wave from a spherical wave to a plane wave.

[0029]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples. In addition, "part" is "part by weight" unless otherwise specified. [Evaluation Method] Voltage standing wave ratio: Measured in accordance with JIS C 5402 5.6. The measurement frequency is 2 GHz. Shape deformation rate: The antenna was heated at 110 ° C. for 1 hour, the shape change of the antenna was observed, and the dimensional change rate before and after heating was obtained.

Example 1 Thermoplastic norbornene resin (ZEONEX 480,
Made by Nippon Zeon Co., Ltd., hydrogenated norbornene ring-opening polymer, Tg of about 140 ° C., hydrogenation rate of 99.7% or more, metal element amount of 1 ppm or less) 100 parts of styrene-ethylene-propylene-styrene block copolymer Polymer elastomer (Septon 2023, Kuraray Co., Ltd.,
Number average molecular weight of about 60,000, Tg of at least 40 ℃
There is one point below, 20 parts of metal element amount (about 15 ppm) and 0.5 parts of phenolic antioxidant are added, and the mixture is kneaded at 220 ° C. by using a twin-screw kneading extruder, and pellets of the thermoplastic resin composition. Got This pellet was injection molded at a resin temperature of 280 ° C. to obtain a JIS K7110 No. 2 test piece,
The IZOD impact strength was determined. IZOD impact strength is 38k
It was J / m. The heat distortion temperature under a load of 18.6 kgf was 133 ° C.

Separately, using the above pellets, 30 mm × 30
A mm × 0.5 mm substrate was obtained by the same injection molding as above. The dielectric loss tangent of this substrate was 0.0015 or less between 1 kHz and 20 GHz. The relative dielectric constant at 2 GHz was 2.3 and the dielectric loss tangent was 0.0004. The water absorption was 0.008%. A plating-resistant resist ink was screen-printed on the surface of the substrate, and a mask was coated on the portions not to be plated so as to form a pattern of the radiation conductor (top plate) and the ground conductor (a part of the side surface of the substrate). Then, etching treatment was performed with a mixed solution of chromic anhydride / concentrated sulfuric acid. Next, the substrate was dipped in a catalyst solution containing palladium and further dipped in hydrochloric acid to deposit palladium on the surface. Then, the mask was peeled off. And thickness 12 by electroless plating
A copper plating layer of μm is formed, a nickel layer of about 5 μm is formed thereon, and a gold plating layer of about 2 μm is further formed, and a radiation conductor layer is formed on the top plate of the substrate and a ground conductor is formed on a part of the side surface. An antenna provided with layers was obtained. When the smoothness of the radiation conductor layer and the ground conductor layer was measured according to JIS-Z8741, the surface glossiness (60 degrees) was 120. The voltage standing wave ratio of the antenna was 1.06 at 2 GHz.
Further, heating was performed at 110 ° C. for 1 hour, and the shape change of the antenna top plate was observed. The shape change rate was 0.01%.

Example 2 Instead of the mask used in Example 1, a thermoplastic polyester elastomer (trade name "Hytrel # SB704" manufactured by Toray-Dupont Co., Ltd.) was used to perform injection molding so as to cover the surface of the substrate. An antenna was obtained in the same manner as in Example 1 except that the mask thus obtained was used. When the smoothness of the radiating conductor layer and the grounding conductor layer was measured according to JIS-Z8741, the surface glossiness (60 degrees) was 260. The voltage standing wave ratio of the antenna was 1.05 at 2 GHz, and the shape change rate was almost 0%.

Comparative Example A resin composition was obtained in the same manner as in Example 1 except that syndiotactic polystyrene was used as the thermoplastic resin. This resin composition was evaluated in the same manner as in Example 1. IZOD impact strength (with notch) is 19kJ
/ M, and the maximum value of the dielectric loss tangent between 1 kHz and 20 GHz was 0.015. The heat distortion temperature under load of 18.6 kgf was 95 ° C. The dielectric constant at 2 GHz was 3.3, the dielectric loss tangent was 0.002, and the water absorption was 0.05%. Example 1 using this resin composition
An antenna was obtained in the same manner as. The surface gloss of the conductor layer is 3
It was 5. The voltage standing wave ratio of this antenna was 1.65 at 2 GHz, which was a very high value. Also, at 110 ℃ 1
After heating for an hour, the shape change of the antenna top plate was observed. The shape change rate was about 2.6%. Since this antenna has a large shape change, it is considered that the resonance frequency fluctuates depending on the usage environment.

[0034]

The voltage standing wave ratio generally increases as the frequency becomes higher. However, in the three-dimensional circuit board of the present invention, the voltage standing wave ratio is small even in the high frequency region, and the shape does not change even when left at high temperature. When applied to etc.,
Since the peak gain is large and the resonance frequency does not change depending on the usage environment, stable communication can be secured in mobile communication devices such as mobile phones.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H05K 3/18 H05K 3/18 E 3/38 3/38 AF term (reference) 4J002 AA01W AC01X AC03X AC06X AC09X BB05X BB15X BG04X BK00W BN15X BN16X BP01X CE00W CH04X CK02X CN02X CP03X GQ00 5E338 AA05 AA16 BB63 BB75 CC01 CD01 EE11 EE21 5E343 AA01 AA12 AA36 AA38 BB24 DD33 BB71 BB62 BB02 BB71 BB71

Claims (5)

[Claims] 1. A thermoplastic resin composition having a dielectric loss tangent of 0.01 or less at 1 kHz to 20 GHz, an IZOD impact strength of 2 kJ / m or more, and a heat deformation temperature of 110 ° C. or more under a load of 18.6 kgf. A three-dimensional circuit board in which a conductor layer is provided on the surface of the substrate, and the surface gloss Gs (60 degrees) of the conductor layer is 50 or more. 2. The three-dimensional circuit board according to claim 1, wherein the resin composition contains an amorphous resin. 3. The three-dimensional circuit board according to claim 2, wherein the amorphous resin is a norbornene-based resin. 4. The three-dimensional circuit board according to claim 1, wherein the resin composition contains a soft polymer. 5. A thermoplastic resin composition having a dielectric loss tangent of 0.01 or less at 1 kHz to 20 GHz, an IZOD impact strength of 2 kJ / m or more, and a heat deformation temperature of 110 ° C. or more under a load of 18.6 kgf, in a predetermined shape. The step of forming a mask on the substrate so as to expose the surface portion of the surface of the substrate on which the conductor layer is to be formed and cover the other surface portion of the surface of the substrate, the surface of the mask and the mask. A step of etching the exposed surface of the substrate, a step of applying a catalyst for electroless plating to the etched surface, a step of removing a mask from the substrate, a predetermined step on the surface of the substrate from which the mask has been removed A method for manufacturing a three-dimensional circuit board, comprising the step of forming a conductor layer of a pattern by electroless plating.