The patent has been granted The patent has been granted, Grant of patent is intended, Request for examination was made, The international publication has been made EP Register Verified

BUSHING FOR PRODUCING GLASS FIBERS AND METHOD FOR PRODUCING GLASS FIBERS

Publication No. EP4328199

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App No. EP22791393

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Filed by Tanaka Kikinzoku Kogyo K.K.

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Filed on 2022-03-10

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Issued/Published on 2025-07-16

Official EPO Register

Publication No. EP4328199 A1

Application No. EP22791393 Filed: 2022-03-10

Grant Date 2025-07-16 Mention of grant

Active Oppositions 1 Active EPO Oppositions

Patent Abstract / Summary

The present invention relates to a bushing for producing glass fibers, including: a plurality of nozzles made of platinum or the like from which molten glass is discharged; and a base plate made of platinum or the like. A coating layer is preferentially formed on an outer circumferential face in a tip part on the side of glass discharge of the nozzle, and a width of the coating layer is 5% or more and 95% or less with respect to the entire length of the nozzle. The base plate includes, in at least a part thereof, a non-coating area not provided with the coating layer. Areas of the nozzles and the base plate not provided with the coating layer act as a sacrificial metal for protecting the nozzle tip parts where the coating layer is formed. In consideration of the action of the sacrificial metal, a coverage rate P of the coating layer in the nozzle tip parts calculated in accordance with a prescribed equation is preferably 5% or more and 350% or less. A cause of nozzle abrasion in a bushing for producing glass fibers is found, and nozzles are minimally abraded in a long-term operation.

IPC Classifications

C03B37/083, C03B37/095 C03B37/083

Priority Claims

JP 20210073632 Date: 2021-04-23

Designated Contracting States (38 EPC States)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

Parties & Representation

Applicants

Tanaka Kikinzoku Kogyo K.K.

7-3, Marunouchi 2-chome Chiyoda-ku, Tokyo 100-6422

Inventors (3)

SEGAWA, Hideo

Isehara-shi, Kanagawa 259-1146

SUZUKI, Jumpei

Isehara-shi, Kanagawa 259-1146

ONOZUMI, Shigekazu

Isehara-shi, Kanagawa 259-1146

Representatives / Agents

Hoffmann Eitle

Patent- und Rechtsanwälte PartmbB, Arabellastraße 30

BiiP bv

Engels Plein 3, b 0102, 3000 Leuven

Key Procedural Dates

Request-For-Examination 2023-11-07

Mention Of Grant Published 2025-07-16

First-Examination-Report-Despatched 2025-04-23

Legal Status & Event History

Official European Patent Office legal and procedural status changes recorded for this file.

53 Events Recorded

Date	Code	Event Description	Auth
2022-10-28	STAA	INFORMATION ON THE STATUS OF AN EP PATENT APPLICATION OR GRANTED EP PATENT	EP
2024-01-26	PUAI	PUBLIC REFERENCE MADE UNDER ARTICLE 153(3) EPC TO A PUBLISHED INTERNATIONAL APPLICATION THAT HAS ENTERED THE EUROPEAN PHASE	EP
2024-01-26	STAA	INFORMATION ON THE STATUS OF AN EP PATENT APPLICATION OR GRANTED EP PATENT	EP
2024-02-28	17P	REQUEST FOR EXAMINATION FILED	EP
2024-02-28	AK	DESIGNATED CONTRACTING STATES	EP
2024-07-31	DAX	REQUEST FOR EXTENSION OF THE EUROPEAN PATENT (DELETED)	EP
2024-07-31	DAV	REQUEST FOR VALIDATION OF THE EUROPEAN PATENT (DELETED)	EP
2024-10-30	RIC1	INFORMATION PROVIDED ON IPC CODE ASSIGNED BEFORE GRANT	EP
2024-10-30	A4	SUPPLEMENTARY SEARCH REPORT DRAWN UP AND DESPATCHED	EP
2025-04-22	GRAP	DESPATCH OF COMMUNICATION OF INTENTION TO GRANT A PATENT	EP
2025-04-22	STAA	INFORMATION ON THE STATUS OF AN EP PATENT APPLICATION OR GRANTED EP PATENT	EP
2025-05-21	INTG	INTENTION TO GRANT ANNOUNCED	EP
2025-06-07	GRAS	GRANT FEE PAID	EP
2025-06-13	GRAA	(EXPECTED) GRANT	EP
2025-06-13	STAA	INFORMATION ON THE STATUS OF AN EP PATENT APPLICATION OR GRANTED EP PATENT	EP
2025-07-09	P01	OPT-OUT OF THE COMPETENCE OF THE UNIFIED PATENT COURT (UPC) REGISTERED	EP
2025-07-16	AK	DESIGNATED CONTRACTING STATES	EP
2025-07-16	REG	REFERENCE TO A NATIONAL CODE	EP
2025-07-31	REG	REFERENCE TO A NATIONAL CODE	EP
2025-08-07	REG	REFERENCE TO A NATIONAL CODE	EP
2025-08-13	REG	REFERENCE TO A NATIONAL CODE	EP
2025-08-27	REG	REFERENCE TO A NATIONAL CODE	EP
2025-12-09	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2025-12-15	REG	REFERENCE TO A NATIONAL CODE	EP
2026-01-08	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-12	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-12	REG	REFERENCE TO A NATIONAL CODE	EP
2026-01-13	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-14	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-15	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-16	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-20	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-22	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-23	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-28	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-01-30	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-06	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-09	PGFP	ANNUAL FEE PAID TO NATIONAL OFFICE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-13	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-13	PGFP	ANNUAL FEE PAID TO NATIONAL OFFICE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-15	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-15	PGFP	ANNUAL FEE PAID TO NATIONAL OFFICE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-16	PGFP	ANNUAL FEE PAID TO NATIONAL OFFICE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-24	PLBI	OPPOSITION FILED	EP
2026-04-23	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-28	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-04-30	REG	REFERENCE TO A NATIONAL CODE	EP
2026-04-16	REG	REFERENCE TO A NATIONAL CODE	EP
2026-05-13	PLAX	NOTICE OF OPPOSITION AND REQUEST TO FILE OBSERVATION + TIME LIMIT SENT	EP
2026-05-27	26	OPPOSITION FILED	EP
2026-06-30	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP
2026-09-15	PLBB	REPLY OF PATENT PROPRIETOR TO NOTICE(S) OF OPPOSITION RECEIVED	EP
2026-10-07	PG25	LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO]	EP

Patent & Non-Patent Citations

Cited documents and prior art referenced in search and examination reports.

4 Citations

Cited Patent Documents

EP0381179 1990-08-08

Espacenet

JP2020040849 2020-03-19

Espacenet

US4846865 1989-07-11

Espacenet

JPH04114928 1992-04-15

Espacenet

Worldwide Patent Family

Related applications and patents in the same INPADOC worldwide family.

12 Family Members

Country	Publication Number	Kind	Publication Date	Action
EP	EP4328199A1	A1	2024-02-28	Espacenet
EP	EP4328199A4	A4	2024-10-30	Espacenet
EP	EP4328199B1	B1	2025-07-16	Espacenet
CN	CN117203169A	A	2023-12-08	Espacenet
CN	CN117203169B	B	2026-01-02	Espacenet
JP	JP7113114B1	B1	2022-08-04	Espacenet
JP	JP2022167675A	A	2022-11-04	Espacenet
TW	TW202248150A	A	2022-12-16	Espacenet
TW	TWI814310B	B	2023-09-01	Espacenet
US	US20240083801A1	A1	2024-03-14	Espacenet
US	US12054417B2	B2	2024-08-06	Espacenet
WO	WO2022224612A1	A1	2022-10-27	Espacenet

Official File Inspection EPC Art. 128 Public Dossier

Complete European Patent Register Dossier (148 Total Documents)

The full inspection file for Application EP22791393 contains 148 total documents, including all notices of opposition, proprietor counter-statements, examination communications, third-party observations, and procedural forms. Below are all major recorded procedural filings and publication specifications.

Open 148-Doc Register Dossier

Dossier Filing

Date: 2026-04-10 Procedure: Examination 0009250

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BUSHING FOR PRODUCING GLASS FIBERS AND METHOD FOR PRODUCING GLASS FIBERS

Patent Abstract / Summary

IPC Classifications

Priority Claims

Designated Contracting States (38 EPC States)

Parties & Representation

Applicants

Inventors (3)

Representatives / Agents

Key Procedural Dates

Patent Oppositions

3B Fibreglass

Legal Status & Event History

Patent & Non-Patent Citations

Cited Patent Documents

Worldwide Patent Family

Complete European Patent Register Dossier (148 Total Documents)

Recorded Filings & Patent Specifications

European Patent Specification - Granted Patent (B1)

Official European Patent Register Full Dossier

European Patent Application with Search Report (A1)

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