GLASS FIBER-REINFORCED RESIN MOLDED ARTICLE

Abstract

Provided is a glass fiber-reinforced resin molded article including low dielectric constant and particularly low dielectric loss tangent, in a high-frequency region of 10 GHz or more. The glass fiber-reinforced resin molded article contains glass fiber in the range of 10 to 90% by mass and a resin in the range of 90 to 10% by mass with respect to the. total amount of the glass fiber-reinforced resin molded article. The glass fiber includes a composition including 52.0 to 59.5% by mass of SiO.sub.2, 17.5 to 25.5% by mass of B.sub.2O.sub.3, 9.0 to 14.0% by mass of Al.sub.2O.sub.3, 0.5 to 6.0% by mass of SrO, 1.0 to 5.0% by mass of MgO, 1.0 to 5.0% by mass of CaO, and 0.1 to 2.5% by mass of F.sub.2 and Cl.sub.2 with respect to the total amount of the glass fiber, and a number average fiber length is 1 to 10000 μm.

Claims

1. A glass fiber-reinforced resin molded article containing glass fiber in a range of 10 to 90% by mass and a resin in a range of 90 to 10% by mass with respect to a total amount of the glass fiber-reinforced resin molded article, wherein the glass fiber comprises a composition including SiO.sub.2 in a range of 52.0 to 59.5% by mass, B.sub.2O.sub.3 in a range of 17.5 to 25.5% by mass, Al.sub.2O.sub.3 in a range of 9.0 to 14.0% by mass, SrO in a range of 0.5 to 6.0% by mass, MgO in a range of 1.0 to 5.0% by mass, CaO in a range of 1.0 to 5.0% by mass, and F.sub.2 and Cl.sub.2 in a range of 0.1 to 2.5% by mass in total with respect to a total amount of the glass fiber, and the glass fiber has a number average fiber length of 1 to 10000 μm.

2. The glass fiber-reinforced resin molded article according to claim 1, wherein the glass fiber has a number average fiber length of 100 to 450 μm.

3. The glass fiber-reinforced resin molded article according to claim 1, wherein the glass fiber has a number average fiber length of 3 to 25 μm.

4. The glass fiber-reinforced resin molded article according to claim 1, wherein the resin included in the glass fiber-reinforced resin molded article is a thermoplastic resin having a dielectric constant of less than 5.0.

5. The glass fiber-reinforced resin molded article according to claim 4, wherein the thermoplastic resin is a polybutylene terephthalate resin.

Description

EXAMPLES

[0115] [Glass Composition]

[0116] Three glass compositions shown in Table 1 were used. Here, a composition A is the glass composition of the glass fiber used in the glass fiber-reinforced resin molded article of the present invention, a composition B is the composition of the glass fiber used in the glass fiber-reinforced resin molded article of Patent Literature 1, and a composition C is a generally used E glass composition. In Table 1, the dielectric constant and dielectric loss tangent at a measurement frequency of 1 MHz are values measured in compliance with IEC 62631-2-1, and the dielectric constant and dielectric loss tangent at a measurement frequency of 1 GHz or 10 GHz are values measured in compliance with KS C 2565:1992.

TABLE-US-00001 TABLE 1 Composi- Composi- Composi- tion A tion B tion C SiO.sub.2 (% by mass) 55.0 54.5 54.6 B.sub.2O.sub.3 (% by mass) 24.0 19.4 6.1 Al.sub.2O.sub.3 (% by mass) 12.0 14.6 14.1 SrO (% by mass) 4.0 0 0 MgO (% by mass) 2.0 4.2 1.2 CaO (% by mass) 2.0 4.1 22.4 F.sub.2 (wt %) 1.0 1.0 0.6 Cl.sub.2 (% by mass) 0 0 0 TiO.sub.2 (wt %) 0 1.9 0.3 Fe.sub.2O.sub.3 (wt %) 0 0.1 0.2 Li.sub.2O + Na.sub.2O + K.sub.2O (wt %) 0 0.2 0.5 ((F.sub.2 + Cl.sub.2) {circumflex over ( )}(⅛) × B.sub.2O.sub.3{circumflex over ( )}3 × Al.sub.2O.sub.3)/ 82.9 — — (1000 × SrO{circumflex over ( )} (½)) Dielectric constant (measurement — 5.0 — frequency: 1 MHz) Dielectric loss tangent (measurement — 0.0007 — frequency: 1 MHz) Dielectric constant (measurement 4.5 4.8 6.8 frequency: 1 GHz) Dielectric loss tangent (measurement 0.0009 0.0014 0.0035 frequency: 1 GHz) Dielectric constant (measurement 4.4 4.7 6.6 frequency: 10 GHz) Dielectric loss tangent (measurement 0.0018 0.0025 0.0061 frequency: 10 GHz)

[0117] [Resin]

[0118] As a polybutylene terephthalate resin (denoted by PBT in the table), DURANEX 2000 (trade name, manufactured by Polyplastics Co., Ltd.) was used. Additionally, used was a polyetheretherketone resin (denoted by PEEK in the table) having a dielectric constant of 3.31 and a dielectric loss tangent of 0.00187 at a measurement frequency of 1 GHz and a dielectric constant of 3.18 and a dielectric loss tangent of 0.00287 at a measurement frequency of 10 GHz.

[0119] [Dielectric Constant]

[0120] The dielectric constant of the glass fiber-reinforced resin molded article was measured in compliance with HS C 2565. The measurement frequency is 1 GHz or 10 GHz.

[0121] [Dielectric Loss Tangent]

[0122] The dielectric loss tangent of the glass fiber-reinforced resin molded article was measured in compliance with JIS C 2565. The measurement frequency is 1 GHz or 10 GHz.

Example 1 and Comparative Examples 1 to 2

[0123] The glass chopped strands of 3 mm in fiber length each comprising the composition A, composition B, or composition C and PBT as shown in Table 2 were kneaded in a twin-screw kneader (manufactured by Toshiba Machine Co., Ltd., trade name: TEM-26SS) to produce resin pellets. Glass fiber-reinforced resin molded articles: (flat plates of 1 mm in thickness) obtained by conducting injection molding using the obtained resin pellets in an injection molding apparatus (manufactured by Nissei Plastic Industrial Co. Ltd., trade name: NEX80) were evaluated for the number average fiber length of the glass fiber, dielectric constant, and dielectric loss tangent by the methods described above.

TABLE-US-00002 TABLE 2 Comparative Comparative Example 1 Example 1 Example 2 Glass Composition Composition A Composition B Composition C fiber Fiber diameter (μm) 11 11 11 Coating Resin type Epoxy Epoxy Epoxy Coating ratio (wt %) 1.0 1.0 1.0 Number average fiber length in 231 235 248 molded article (μm) Content in molded article (wt %) 30.0 30.0 30.0 Resin Resin type PBT PBT PBT Content in molded article (wt %) 70.0 70.0 70.0 Molded 10 GHz dielectric constant 3.13 3.19 3.40 article 1 GHz dielectric constant 3.23 3.29 3.51 (10 GHz dielectric constant)/ 0.97 0.97 0.97 (1 GHz dielectric constant) 10 GHz dielectric loss tangent 0.00513 0.00531 0.00637 1 GHz dielectric loss tangent 0.00624 0.00625 0.00685 (10 GHz dielectric loss tangent)/ 0.82 0.85 0.93 (1 GHz dielectric loss tangent)

[0124] As shown in Table 2, it can be seen that, in the glass fiber-reinforced resin molded article of Example 1 comprising the glass composition defined in the present invention (composition A), the dielectric constant and dielectric loss tangent at 10 are reduced and particularly, the dielectric loss tangent at 10 GHz is markedly reduced, in comparison with the glass fiber-reinforced resin molded article of Comparative Example 1 or 2, which comprises exactly the same composition as that of Example 1 except for the glass composition.

Example 2 and Comparative Examples 3

[0125] The cut fiber of 0.030 rum in fiber length comprising the composition A or the cut fiber of 0.030 mm in fiber length comprising the composition B (the fiber length of the cut fiber comprising the composition B may range from 0.001 to 0.300 mm.) and PBT as shown in Table 3 were kneaded in a twin-screw kneader (manufactured by Toshiba Machine Co., Ltd., trade name: TEM-26SS) to produce resin pellets. Glass fiber-reinforced resin molded articles (fiat plates of 1 mm in thickness) obtained by conducting injection molding using the obtained resin pellets in an injection molding apparatus (manufactured by Nissei Plastic Industrial Co. Ltd., trade name: NEX80) were evaluated for the number average fiber length of the glass fiber, dielectric constant, and dielectric loss tangent by the methods described above.

TABLE-US-00003 TABLE 3 Comparative Example 2 Example 3 Glass Composition Composi- Composi- fiber tion A tion B Fiber diameter (μm) 11 11 Number average fiber length in 18 17 molded article (μm) Content in molded article (wt %) 30 30 Resin Resin type PBT PBT Content in molded article (wt %) 70 70 Molded 10 GHz dielectric constant 3.10 3.17 article 1 GHz dielectric constant 3.20 3.27 (10 GHz dielectric constant)/ 0.97 0.97 (1 GHz dielectric constant) 10 GHz dielectric loss tangent 0.00511 0.00530 1 GHz dielectric loss tangent 0.00623 0.00625 (10 GHz dielectric loss tangent)/ 0.82 0.85 (1 GHz dielectric loss tangent)

Example 3 and Comparative Examples 4

[0126] The glass chopped strands of 3 mm in fiber length each having the composition A or the composition B and PEEK as shown in Table 4 were kneaded in a twin-screw kneader (manufactured by Toshiba Machine Co., Ltd., trade name: TEM-26SS) to produce resin pellets. Glass fiber-reinforced resin molded articles (flat plates of 1 mm in thickness) obtained by conducting injection molding using the obtained resin pellets in an injection molding apparatus (manufactured by Nissei Plastic Industrial Co. Ltd., trade name: NEX80) were evaluated for the number average fiber length of the glass fiber, dielectric constant, and dielectric loss tangent by the methods described above.

TABLE-US-00004 TABLE 4 Comparative Example 3 Example 4 Glass Composition Composi- Composi- fiber tion A tion B Fiber diameter (μm) 11 11 Number average fiber length in 220 226 molded article (μm) Content in molded article (wt %) 40 40 Resin Resin type PEEK PEEK Content in molded article (wt %) 60 60 Molded 10 GHz dielectric constant 3.78 3.86 article 1 GHz dielectric constant 3.91 3.99 (10 GHz dielectric constant)/ 0.97 0.97 (1 GHz dielectric constant) 10 GHz dielectric loss tangent 0.00211 0.00270 1 GHz dielectric loss tangent 0.00122 0.00152 (10 GHz dielectric loss tangent)/ 1.73 1.78 (1 GHz dielectric loss tangent)

[0127] As shown in Table 4, it can be seen that, in the glass fiber-reinforced resin molded article of Example 3 comprising the glass composition defined in the present invention (composition A), the dielectric constant and dielectric loss tangent at 10 GHz are reduced and particularly, the increase in the dielectric loss tangent at 10 GHz is markedly suppressed, in comparison with the glass fiber-reinforced resin molded article of Comparative Example 4, comprising exactly the same composition as that of Example 1 except for the glass composition.