Glass cloth, prepreg, and glass fiber-reinforced resin molded product

Patent metadata

Field	Value
Publication number	US-11746447-B2
Application number	US-202017599133-A
Country	US
Kind code	B2
Filing date	Aug 20, 2020
Priority date	Aug 27, 2019
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

A glass cloth including warp yarns and weft yarns that are glass yarns each formed by bundling 30 to 44 glass filaments each having a circle-equivalent diameter of 3.0 to 4.4 μm, wherein the weaving density of the warp yarns and the weft yarns is 85 to 125 yarns/25 mm, at least either of the warp yarn and the weft yarn is a flat glass yarn formed of flat glass filaments, the weaving density thereof is less than 100 yarns/25 mm, the major axis DL of the flat glass filament is 3.3 to 6.0 μm, the minor axis DS is 2.0 to 3.9 μm, the number of twists T of each of the flat glass yarns is 0.70 twists/25 mm or less, and the number of the flat glass filaments F constituting each of the flat glass yarns, T, DL, and DS satisfy the following expression:

89.0
≤

F
×

(

DL
×

(

1
-

T

1
/
2

)

+

DS
×

T

1
/
2

)

/

(

DL
/
DS

)

≤

129.0
.

First claim

The invention claimed is:

1. A glass cloth comprising warp yarns and weft yarns that are glass yarns each formed by bundling glass filaments, wherein
a number of the glass filaments bundled in each of the warp yarns and the weft yarns is in a range of 30 to 44 filaments, and each of the glass filaments having a circle-equivalent diameter in a range of 3.0 to 4.4 μm,
the warp yarns and the weft yarns are flat glass yarns composed of flat glass filaments each having a flat cross-sectional shape,
a weaving density of the flat warp yarns and weft yarns is in a range of 85 to 100 yarns/25 mm,
a major axis DL of the flat cross section of each of the flat glass filaments is in a range of 3.3 to 6.0 μm, a minor axis DS of the flat cross section of each of the flat glass filaments is in a range of 2.0 to 3.9 μm,
the major axis DL is a higher value than the minor axis DS,
a ratio of the DL to the DS is in a range of 1.25 to 1.80,
a number of twists T of each of the flat glass yarns is equivalent to or less than 0.70 twists/25 mm, and
the number of the flat glass filaments F constituting each of the flat glass yarns, the number of twists T, the major axis DL, and the minor axis DS satisfy the following expression (1):

89.0
≤

F
×

(

DL
×

(

1
-

T

1
/
2

)

+

DS
×

T

1
/
2

)

/

(

DL
/
DS

)

≤

129.0
.

(
1
)

2. The glass cloth according to claim 1 , wherein the number of the flat glass filaments F constituting each of the flat glass yarns, the number of twists T, the major axis DL, and the minor axis DS satisfy the following expression (2):

97.0
≤

F
×

(

DL
×

(

1
-

T

1
/
2

)

+

DS
×

T

1
/
2

)

/

(

DL
/
DS

)

≤

122.5
.

(
2
)

3. A prepreg comprising the glass cloth according to claim 1 .

4. A glass fiber-reinforced resin molded product comprising the glass cloth according to claim 1 .

Assignees

• Nitto Boseki Co Ltd

Inventors

• Ikejiri Hirotaka
• Awano Masahiro
• TAKATSU Kimihiro

Classifications

• D03D15/267 Primary

  Glass · CPC title

• C08J5/244

  using glass fibres · CPC title

• D03D15/37

  with specific cross-section or surface shape · CPC title

• D03D15/41

  with specific twist · CPC title

• D03D15/46

  Flat yarns, e.g. tapes or films · CPC title