IP Library Granted Patent US 12,630,468
Granted Patent B2
US 12,630,468 · App. 17/777,317 · Granted May 19, 2026

Glass composition for glass fibers, glass fibers, glass fiber fabric, and glass fiber-reinforced resin composition

Inventors: Masaru Urushizaki (Fukushima, JP); Takanobu Hosokawa (Fukushima, JP); Takashi Nonaka (Fukushima, JP)
Assignee: Nitto Boseki Co, Ltd.
C03C13/00C03C3/091C08K7/14D03D15/267C03C2213/00
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Quick Facts
Patent No.
US 12,630,468
App. No.
17/777,317
Granted
May 19, 2026
Kind
B2
Abstract

To provide a glass composition for glass fiber having a low dielectric loss tangent, suppressing the occurrence of phase separation, having a reduced viscosity at high temperatures, and reducing the occurrence of striae. The glass composition for glass fiber includes 52.0 to 57.5% by mass of SiO 2 , 19.5 to 25.5% by mass of B 2 O 3 , 8.0 to 13.0% by mass of Al 2 O 3 , 0 to 2.0% by mass of MgO, 0 to 6.0% by mass of CaO, 0.5 to 6.5% by mass of SrO, and 0.1 to 3.0% by mass of TiO 2 , the ratio of Al 2 O 3 to B 2 O 3 is 0.35 to 0.54, and the content SI of SiO 2 , the content B of B 2 O 3 , the content M of MgO, the content C of CaO, the content SR of SrO, and the content T of TiO 2 satisfy the following formula (1): 6.90≤100×(B/SI) 2 ×{SR/(C+SR)} 2/3 ×{T/(M+T)} 1/2 ≤12.30 (1).

Claims (23)

1 . A glass composition for glass fiber comprising:

SiO 2 in a range of 52.0% by mass or more and 57.5% by mass or less;

B 2 O 3 in a range of 19.5% by mass or more and 25.5% by mass or less;

Al 2 O 3 in a range of 8.0% by mass or more and 13.0% by mass or less;

MgO in a range of 0% by mass or more and 2.0% by mass or less;

CaO in a range of 0% by mass or more and 4.9% by mass or less;

SrO in a range of 0.5% by mass or more and 6.5% by mass or less;

TiO 2 in a range of 0.1% by mass or more and 3.0% by mass or less; and

ZnO in a range of 0% by mass or more and 0.5% by mass or less with respect to a total amount, wherein

a ratio of a content of Al 2 O 3 (% by mass) to a content of B 2 O 3 (% by mass), (Al 2 O 3 /B 2 O 3 ), is in a range of 0.35 to 0.54, and

a content SI (% by mass) of SiO 2 , a content B (% by mass) of B 2 O 3 , a content M (% by mass) of MgO, a content C (% by mass) of CaO, a content SR (% by mass) of SrO, and a content T (% by mass) of TiO 2 satisfy following formula (1):

6.90≤100×( B/SI ) 2 ×{SR /( C+SR )} 2/3 ×{T /( M+T )} 1/2 ≤12.30  (1).

2 . The glass composition for glass fiber according to claim 1 , wherein the SI, B, M, C, SR, and T satisfy following formula (2):

9.56≤100×( B/SI ) 2 ×{SR /( C+SR )} 2/3 ×{T /( M+T )} 1/2 ≤11.77  (2).

3 . The glass composition for glass fiber according to claim 2 , wherein the SI, B, M, C, SR, and T satisfy following formula (3):

10.00≤100×( B/SI ) 2 ×{SR /( C+SR )} 2/3 ×{T /( M+T )} 1/2 ≤11.35  (3).

4 . The glass composition for glass fiber according to claim 3 , wherein the SI, B, M, C, SR, and T satisfy following formula (4):

10.15≤100×( B/SI ) 2 ×{SR /( C+SR )} 2/3 ×{T /( M+T )} 1/2 ≤10.85  (4).

5 . The glass composition for glass fiber according to claim 4 , wherein the SI, B, M, C, SR, and T satisfy following formula (5):

10.35≤100×( B/SI ) 2 ×{SR /( C+SR )} 2/3 ×{T /( M+T )} 1/2 ≤10.78  (5).

6 . Glass fiber formed from the glass composition for glass fiber according to claim 1 .

7 . A glass fiber woven fabric comprising the glass fiber according to claim 6 .

8 . A glass fiber-reinforced resin composition comprising the glass fiber according to claim 6 .

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 17, 2022
From: URUSHIZAKI, MASARU; HOSOKAWA, TAKANOBU; NONAKA, TAKASHI
To: NITTO BOSEKI CO., LTD.
Reel/Frame 059929/0438 →
Priority Claims (1)
JP 2020-071189 · Apr 10, 2020 · national
Continuity (1)
Related Publication 20220402810A1 · Dec 22, 2022
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