Glass filler and method for producing the same, and resin-containing composition including glass filler
Provided is a novel glass filler having a low permittivity. The glass filler provided includes a glass composition, wherein the glass composition includes, in wt %: 95≤SiO 2 ≤99.5; 0≤B 2 O 3 ≤2; 0.01≤Al 2 O 3 ≤4; 0≤R 2 O≤4; 0.01≤RO≤4; and 0≤TiO 2 ≤4, where RO is at least one selected from MgO, CaO, SrO, and ZnO, and R 2 O is at least one selected from Li 2 O, Na 2 O, and K 2 O. This glass filler can have a permittivity of less than 4 at 1 GHz.
1 . A glass filler comprising a glass composition, wherein
the glass composition comprises, in wt %:
95≤SiO 2 ≤99.5;
0≤B 2 O 3 ≤2;
0.01≤Al 2 O 3 ≤4;
0≤R 2 O≤4;
0.2≤RO≤1.5; and
0.1≤TiO 2 ≤2,
where RO is at least one compound selected from the group consisting of MgO, CaO, SrO, and ZnO, and R 2 O is at least one compound selected from the group consisting of Li 2 O, Na 2 O, and K 2 O.
2 . The glass filler according to claim 1 , wherein
the glass composition comprises, in wt %:
95≤SiO 2 ≤99;
0≤B 2 O 3 ≤2;
0.01≤Al 2 O 3 ≤2;
0≤R 2 O≤2;
0.2≤RO≤1.5; and
0.1≤TiO 2 ≤2.
3 . The glass filler according to claim 1 , wherein
the glass composition is substantially free of T-Fe 2 O 3 , where the T-Fe 2 O 3 represents total iron oxide calculated as Fe 2 O 3 .
4 . The glass filler according to claim 1 , wherein
the glass composition is substantially free of R 2 O.
5 . The glass filler according to claim 1 , wherein
the glass composition comprises, in wt %,
95≤SiO 2 ≤99;
0≤B 2 O 3 ≤2;
0.01≤Al 2 O 3 ≤4;
0.4≤R 2 O≤2;
0.2≤RO≤1.5; and
0.1≤TiO 2 ≤2.
6 . The glass filler according to claim 1 , wherein
the glass composition comprises, in wt %,
0.25≤TiO 2 ≤2.
7 . The glass filler according to claim 1 , wherein
the glass composition comprises, in wt %,
97.5≤SiO 2 ≤99.
8 . The glass filler according to claim 1 , wherein
the glass composition comprises, in wt %,
0.2≤Al 2 O 3 ≤0.6.
9 . The glass filler according to claim 1 , wherein
the glass composition comprises, in wt %:
0.05≤MgO≤0.5; and
0.1≤CaO≤1.
10 . The glass filler according to claim 1 , having a permittivity of less than 4 at a frequency of 1 GHz.
11 . The glass filler according to claim 1 , having a surface roughness Ra of 0 to 100 nm.
12 . The glass filler according to claim 1 , having a specific surface area of 0.03 to 10 m 2 /g.
13 . The glass filler according to claim 1 , having a pore volume of 0 to 0.1 cm 3 /g.
14 . The glass filler according to claim 1 , wherein the form of the glass filler is at least one selected from the group consisting of a glass flake, a chopped strand, a milled fiber, a glass powder, a glass bead, and a flat fiber.
15 . A resin-containing composition comprising:
the glass filler according to claim 1 ; and
a resin.
16 . A method for producing the glass filler according to claim 1 , the method comprising:
producing a glass filler precursor including a base glass composition; and
eluting at least partially the base glass composition from the glass filler precursor a so as to obtain the glass filler, which has a glass composition differing in composition from a glass composition of the base glass composition.
17 . The method according to claim 16 , further comprising
heat treating after the eluting, wherein
in the heat treating, a heat treatment at 1000° C. or higher is performed.
18 . The method according to claim 16 , wherein
a SiO 2 content on a weight basis in the glass composition included in the glass filler is higher than a SiO 2 content on a weight basis in the base glass composition.