# US 5,334,645 A · Substrate for circuit board including the glass fibers as reinforcing material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,334,645 A - Document ID: US5334645A - Status: Granted - Kind: A - Application number: 08/148,330 - Filed: 1993-11-08 - Granted: 1994-08-02 - Earliest claimed: 1991-02-08 - Assignees: Matsushita Electric Works, Ltd.; Nippon Electric Glass Co., Ltd. - Inventors: Kiyotaka Komori; Seishiro Yamakawa; Shigeru Yamamoto; Jun Naka; Tadashi Kokubo - Web page: https://patentgrep.com/patent/US5334645A ## CPC - C03C 3/097: containing phosphorus, niobium or tantalum - C03C 3/091: containing aluminium - C03C 3/102: containing lead - C03C 13/00: Fibre or filament compositions (manufacture of fibres or filaments C03B37/00) - H05K 1/0326: {containing O} - H05K 1/0366: {reinforced, e.g. by fibres, fabrics (H05K1/036 takes precedence)} - H05K 1/0373: {containing additives, e.g. fillers (H05K1/036 takes precedence)} - H05K 2201/0116: Porous, e.g. foam - H05K 2201/0209: Inorganic, non-metallic particles - C03C: CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract A glass fiber forming composition exhibits a remarkably high dielectric constant .epsilon..sub.r as well as superior chemical resistance, yet it is readily spun into glass fibers. The composition is characterized to show a devitrification temperature which is lower than a spinning temperature at which the glass composition exhibits a viscosity of 10.sup.2.5 poise, so as to be readily spun into corresponding glass fibers. The composition consists essentially of 40 to 65 mol % of SiO.sub.2 ; 20 to 45 mol % of at least one component selected from the group consisting of MgO, CaO, SrO and BaO; 5 to 25 mol % of at least one component selected from the group consisting of TiO.sub.2 and ZrO.sub.2 ; and 0.5 to 15 mol % of NbO.sub.5/2 as calculated from an incorporated amount of Nb.sub.2 O.sub.5. Alternately, the composition consist essentially of 40 to 65 mol % of SiO.sub.2 ; 20 to 45 mol % of at least one component selected from the group consisting of CaO, SrO and BaO; 5 to 25 mol % of at least one component selected from the group consisting of TiO.sub.2 and ZrO.sub.2 ; 0.5 to 15 mol % of NbO.sub.5/2 as calculated from an incorporated amount of Nb.sub.2 O.sub.5 ; and 0.5 to 15 mol % of AlO.sub.3/2 as calculated from an incorporated amount of Al.sub.2 O.sub.3. The composition is also characterized to incorporate at least 85 mol % of a total amount of the oxides and have a dielectric constant [.epsilon..sub.r ] of 9 or more at 1 MHz and 25.degree. C. ## Claims ### Claim 1 A substrate for circuit board comprising: a layer made of a resin; a reinforcing member embedded in said layer, said reinforcing member composed of glass fibers which are made from a glass composition, said glass composition comprising at least 85 mol % of an oxide mixture, said oxide mixture consisting essentially of: 40 to 65 mol % of SiO.sub.2 ; MgO, CaO, SrO and BaO in amounts which total 20 to 45 mol % of said oxide mixture; TiO.sub.2 and ZrO.sub.2 in amounts which total 5 to 25 mol % of said oxide mixture; 0.5 to 15 mol % of NbO.sub.5/2 ; said composition having a dielectric constant .epsilon..sub.r of 9 or more at 1 MHz and 25.degree. C.; and said composition being characterized to show a devitrification temperature which is lower than a spinning temperature at which said composition exhibits a viscosity of 10.sub.2.5 poise. ### Claim 2 A substrate for circuit board comprising: a layer made of a resin; a reinforcing member embedded in said layer, said reinforcing member composed of glass fibers which are made from a glass composition, said glass composition comprising at least 85 mol % of an oxide mixture, said oxide mixture consisting essentially of: 40 to 65 mol % of SiO.sub.2 ; Cao SrO and Bao in amounts which total 20 to 45 mol % of said oxide mixture; TiO.sub.2 and ZrO.sub.2 in amounts which total 5 to 25 mol % of said oxide mixture; 0.5 to 15 mol % of NbO.sub.5/2 ; 0.5 to 15 mol % of AlO.sub.3/2 ; said composition having a dielectric constant .epsilon..sub.r of 9 or more at 1 MHz and 25.degree. C.; and said composition being characterized to show a devitrification temperature which is lower than a spinning temperature at which said composition exhibits a viscosity of 10.sub.2.5 poise. ### Claim 3 (depends on 1, 2) A substrate for circuit board as set forth in claim 1 or 2, wherein said reinforcing member is provided in the form of a glass cloth which is a woven fabric of said glass fibers. ### Claim 4 (depends on 1, 2) A substrate for circuit board as set forth in claim 1 or 2, wherein said reinforcing member is provided in the form of a glass mat which is a unwoven fabric of said glass fibers. ### Claim 5 (depends on 1, 2) A substrate for circuit board as set forth in claim 1 or 2, wherein said resin comprises a polyphenylene oxide composition comprising polyphenylene oxide and at least one member selected from the group consisting of cross-linking polymer and cross-linking monomer. ### Claim 6 (depends on 5) A substrate for circuit board as set forth in claim 5, wherein said resin comprises at least 7% by weight, based the total weight of the of polyphenylene oxide composition, of polyphenylene oxide. ### Claim 7 (depends on 5) A substrate for circuit board as set forth in claim 5, wherein said cross-linking polymer comprises at least one constituent selected from the group consisting of 1.2-polybutadiene, 1.4-polybutadiene, styrene-butadiene copolymer, denatured 1.2-polybutadiene, and rubbers. ### Claim 8 (depends on 5) A substrate for circuit board as set forth in claim 5, wherein said cross-linking monomer comprises at least one constituent selected from the group consisting of ester acrylate, epoxy acrylate, urethane acrylate, ether acrylate, melamine acrylate, alkyd acrylate, silicon acrylate, triallyl cyanurate, triallyl isocyanurate, ethylene glycol dimethacrylate, divinyl benzene, diallyl phthalate, vinyl toluene, ethyl vinyl benzene, styrene, paramethylstyrene, and multifunctional epoxy. ### Claim 9 (depends on 2) A substrate for circuit board as set forth in claim 2, further comprising inorganic dielectric particles dispersed in said layer of resin. ### Claim 10 (depends on 9) A substrate for circuit board as set forth in claim 9, wherein said inorganic dielectric particles are substantially non-porous particles having an average particle size of 1 to 5 .mu.m and a specific surface area of 0.2 to 3.0 m.sup.2 /g. ### Claim 11 (depends on 9) A substrate for circuit board as set forth in claim 9, wherein said inorganic dielectric particles are porous particles. ### Claim 12 (depends on 11) A substrate for circuit board as set forth in claim 11, wherein said inorganic dielectric particles have an average particle size of 5 to 100 .mu.m and a specific surface area of 0.3 to 7.0 m.sup.2 /g. ### Claim 13 (depends on 11) A substrate for circuit board as set forth in claim 11, wherein said inorganic dielectric particles are agglomerated particles formed from primary particles thereof. ### Claim 14 (depends on 13) A substrate for circuit board as set forth in claim 13, wherein said agglomerated particles are formed by sintering of said primary particles. ### Claim 15 (depends on 13) A substrate for circuit board as set forth in claim 13, wherein said agglomerated particles are formed by sintering of said primary particles in the presence of a sintering aid. ### Claim 16 (depends on 9) A substrate for circuit board as set forth in claim 9, wherein said inorganic dielectric particles comprise a compound having a perovskite crystalline structure.