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
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PREPARATION METHOD FOR SUPER ABSORBENT POLYMER
Publication No.
EP4257633
•
App No.
EP22904707
•
Filed by
LG Chem, Ltd.
•
Filed on
2022-12-09
•
Issued/Published on
2025-07-23
Publication No.
EP4257633
A1
Application No.
EP22904707
Filed: 2022-12-09
Grant Date
2025-07-23
Mention of grant
Active Oppositions
1 Active
EPO Oppositions
Patent Abstract / Summary
Provided is a method of preparing a superabsorbent polymer. More particularly, provided is a method of preparing a superabsorbent polymer, in which variations in centrifugal retention capacity of superabsorbent polymer particles to be prepared are reduced by controlling heat treatment temperature conditions in a surface crosslinking step, thereby improving absorption properties of the superabsorbent polymer finally prepared.
IPC Classifications
C08J3/24, C08J3/12, C08K5/053, C08K5/109, C08K5/1515, C08J3/075
C08J3/24, C08J3/12, C08K5/053, C08K5/109, C08K5/1515
Priority Claims
KR 20210177007
Date: 2021-12-10
KR 20220170466
Date: 2022-12-08
Designated Contracting States (39 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
ME
MK
MT
NL
NO
PL
PT
RO
RS
SE
SI
SK
SM
TR
Parties & Representation
Applicants
LG Chem, Ltd.
128, Yeoui-daero
KRLg Chem, Ltd.
128, Yeoui-daero
KRInventors (3)
LEE, Jin Woo
Daejeon 34122
KRKIM, Jun Kyu
Daejeon 34122
KRKIM, Changhun
Daejeon 34122
KRRepresentatives / Agents
Plasseraud IP
104 Rue de Richelieu, CS92104
FRHerzog IP Patentanwalts GmbH
Steinstraße 16-18, 40212 Düsseldorf
DEKey Procedural Dates
Request-For-Examination
2023-07-05
Mention Of Grant Published
2025-07-23
First-Examination-Report-Despatched
2025-04-09
Patent Oppositions
Official opposition proceedings filed against European Patent EP4257633 under EPC Article 99.
#1
Opponent
Company
Nippon Shokubai Co., Ltd.
Kogin Bldg., 4-1-1 Koraibashi, JP
Representative
Herzog IP Patentanwalts GmbH
Filing
Date
Opposition in Progress
2026-04-22
Legal Status & Event History
Official European Patent Office legal and procedural status changes recorded for this file.
| Date | Code | Event Description | Auth |
|---|---|---|---|
| 2023-06-16 | STAA | INFORMATION ON THE STATUS OF AN EP PATENT APPLICATION OR GRANTED EP PATENT | EP |
| 2023-09-08 | PUAI | PUBLIC REFERENCE MADE UNDER ARTICLE 153(3) EPC TO A PUBLISHED INTERNATIONAL APPLICATION THAT HAS ENTERED THE EUROPEAN PHASE | EP |
| 2023-09-08 | STAA | INFORMATION ON THE STATUS OF AN EP PATENT APPLICATION OR GRANTED EP PATENT | EP |
| 2023-10-11 | 17P | REQUEST FOR EXAMINATION FILED | EP |
| 2023-10-11 | AK | DESIGNATED CONTRACTING STATES | EP |
| 2024-06-11 | TPAC | OBSERVATIONS FILED BY THIRD PARTIES | EP |
| 2024-07-31 | RIC1 | INFORMATION PROVIDED ON IPC CODE ASSIGNED BEFORE GRANT | EP |
| 2024-07-31 | A4 | SUPPLEMENTARY SEARCH REPORT DRAWN UP AND DESPATCHED | EP |
| 2025-03-19 | DAX | REQUEST FOR EXTENSION OF THE EUROPEAN PATENT (DELETED) | EP |
| 2025-03-19 | DAV | REQUEST FOR VALIDATION OF THE EUROPEAN PATENT (DELETED) | EP |
| 2025-04-08 | GRAP | DESPATCH OF COMMUNICATION OF INTENTION TO GRANT A PATENT | EP |
| 2025-04-08 | STAA | INFORMATION ON THE STATUS OF AN EP PATENT APPLICATION OR GRANTED EP PATENT | EP |
| 2025-05-14 | INTG | INTENTION TO GRANT ANNOUNCED | EP |
| 2025-06-07 | GRAS | GRANT FEE PAID | EP |
| 2025-06-20 | GRAA | (EXPECTED) GRANT | EP |
| 2025-06-20 | STAA | INFORMATION ON THE STATUS OF AN EP PATENT APPLICATION OR GRANTED EP PATENT | EP |
| 2025-07-23 | AK | DESIGNATED CONTRACTING STATES | EP |
| 2025-07-23 | REG | REFERENCE TO A NATIONAL CODE | EP |
| 2025-07-31 | REG | REFERENCE TO A NATIONAL CODE | EP |
| 2025-08-14 | REG | REFERENCE TO A NATIONAL CODE | EP |
| 2025-08-20 | P01 | OPT-OUT OF THE COMPETENCE OF THE UNIFIED PATENT COURT (UPC) REGISTERED | EP |
| 2025-08-13 | REG | REFERENCE TO A NATIONAL CODE | EP |
| 2025-11-26 | 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 |
| 2025-12-15 | PG25 | LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO] | EP |
| 2026-01-08 | PG25 | LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO] | EP |
| 2026-01-08 | PGFP | ANNUAL FEE PAID TO NATIONAL OFFICE [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 |
| 2026-01-15 | PGFP | ANNUAL FEE PAID TO NATIONAL OFFICE [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 |
| 2026-01-16 | PGFP | ANNUAL FEE PAID TO NATIONAL OFFICE [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 |
| 2026-03-17 | 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 |
| 2026-04-13 | PG25 | LAPSED IN A CONTRACTING STATE [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 |
| 2026-04-24 | 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 |
| 2026-04-22 | 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 |
| 2026-07-04 | PG25 | LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO] | EP |
| 2026-07-23 | REG | REFERENCE TO A NATIONAL CODE | EP |
| 2026-08-18 | PG25 | LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO] | EP |
| 2026-08-26 | PG25 | LAPSED IN A CONTRACTING STATE [ANNOUNCED VIA POSTGRANT INFORMATION FROM NATIONAL OFFICE TO EPO] | EP |
| 2026-09-11 | PLAF | INFORMATION MODIFIED RELATED TO COMMUNICATION OF A NOTICE OF OPPOSITION AND REQUEST TO FILE OBSERVATIONS + TIME LIMIT | EP |
| 2026-10-09 | 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.
Cited Patent Documents
EP3424988
2019-01-09
Espacenet
EP3318596
2018-05-09
Espacenet
EP3540001
2019-09-18
Espacenet
WO2012070845
Espacenet
EP3401354
Espacenet
EP3156427
Espacenet
EP3415550
Espacenet
EP3345958
Espacenet
EP3088446
Espacenet
EP3196231
Espacenet
EP3342800
Espacenet
EP3375810
Espacenet
EP2471846
Espacenet
EP3543281
Espacenet
JP2020037625
Espacenet
EP2471845
Espacenet
US5409771
Espacenet
US4666983
Espacenet
US2008125533
Espacenet
JPH11263850
Espacenet
WO2017087158
Espacenet
WO2020089013
Espacenet
Non-Patent Scientific Literature (NPL)
- F. L. BUCHHOLZ, A. T. GRAHAM: "MODERN SUPERABSORBENT POLYMER TECHNOLOGY", 1 January 1998, WILEY-VCH; US , ISBN: 0-471-19411-5, article ANDREW T. GRAHAM, LARRY R. WILSON: "Passage", pages: 55 - 60, XP009566593
- F. L. BUCHHOLZ, A. T. GRAHAM: "MODERN SUPERABSORBENT POLYMER TECHNOLOGY", 1 January 1998, WILEY-VCH; US , ISBN: 0-471-19411-5, article ANDREW T. GRAHAM, LARRY R. WILSON: "Chapter 3: Commercial Processes for the Manufacture of Superabsorbent Polymers", pages: 69 - 117, XP009566605
- ANONYMOUS: "Standard Test Methods for the Nonwovens Industry", WORLDWIDE STRATEGIC PARTNERS - EDANA, 1 January 2005 (2005-01-01), XP055791920
- D23 - Experimental report concerning the reproduction of Example 1 of D11
- D24 - Experimental report concerning the reproduction of Example 7 of D4
- D25 - Experimental report showing the influence of the degree of
neutralization on the absorption properties
Worldwide Patent Family
Related applications and patents in the same INPADOC worldwide family.
| Country | Publication Number | Kind | Publication Date | Action |
|---|---|---|---|---|
| EP | EP4257633A1 | A1 | 2023-10-11 | Espacenet |
| EP | EP4257633A4 | A4 | 2024-07-31 | Espacenet |
| EP | EP4257633B1 | B1 | 2025-07-23 | Espacenet |
| CN | CN116761838A | A | 2023-09-15 | Espacenet |
| JP | JP2024503419A | A | 2024-01-25 | Espacenet |
| JP | JP7648287B2 | B2 | 2025-03-18 | Espacenet |
| KR | KR20230088270A | A | 2023-06-19 | Espacenet |
| KR | KR102892316B1 | B1 | 2025-11-27 | Espacenet |
| US | US20240075456A1 | A1 | 2024-03-07 | Espacenet |
| WO | WO2023106878A1 | A1 | 2023-06-15 | Espacenet |
Official File Inspection
EPC Art. 128 Public Dossier
Complete European Patent Register Dossier (148 Total Documents)
The full inspection file for Application EP22904707 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.
Recorded Filings & Patent Specifications
Official publication specifications, opposition filings, proprietor replies, and procedural submissions.
European Patent Specification - Granted Patent (B1)
Publication Specification
Date: 2025-07-23
Procedure: Grant
EP4257633B1
Official European Patent Register Full Dossier
Publication Specification
Date: 2025-07-23
Procedure: All Proceedings (Examination & Opposition)
EP22904707
European Patent Application with Search Report (A1)
Publication Specification
Date: 2023-06-15
Procedure: Publication
EP4257633A1
Change: Communication of a notice of opposition and request to file observations + time limit
Dossier Filing
Date: 2026-09-11
Procedure: Opposition
EPIDOSCOBS2
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-08-28
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-08-21
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-07-10
Procedure: Examination
0009250
New entry: Communication of a notice of opposition and request to file observations + time limit
Dossier Filing
Date: 2026-05-13
Procedure: Opposition
EPIDOSNOBS2
Invitation to proprietor to file observations on the notice of opposition
Procedural Step
Date: 2026-05-13
Procedure: Opposition
OBSO
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-05-01
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-04-24
Procedure: Examination
0009250
Opposition filed
Dossier Filing
Date: 2026-04-24
Procedure: Opposition
0009260
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-04-10
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-03-20
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-02-06
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-01-23
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2026-01-09
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2025-12-26
Procedure: Examination
0009250
Lapse of the patent in a contracting state
Dossier Filing
Date: 2025-12-12
Procedure: Examination
0009250
(Expected) grant
Dossier Filing
Date: 2025-06-20
Procedure: Grant
0009210
New entry: Payment of fee for grant
Dossier Filing
Date: 2025-06-07
Procedure: Grant
EPIDOSNIGR3
New entry: Payment of fee for publishing/printing
Dossier Filing
Date: 2025-06-07
Procedure: Examination
EPIDOSNIGR5
New entry: Receipt of the translation of the claim(s)
Dossier Filing
Date: 2025-06-07
Procedure: Examination
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Date: 2025-04-09
Procedure: Grant
IGRA
New entry: Communication of intention to grant a patent
Dossier Filing
Date: 2025-04-08
Procedure: Grant
EPIDOSNIGR1
Change - extension states
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Date: 2025-02-14
Procedure: Examination
0009199EXPT
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Date: 2025-02-14
Procedure: Examination
0009199VAPT
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Dossier Filing
Date: 2024-12-24
Procedure: Examination
EPIDOSNRFE2
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Procedural Step
Date: 2024-12-24
Procedure: Examination
RFEE
Amendment by applicant
Dossier Filing
Date: 2024-11-15
Procedure: Examination
EPIDOS ABEX
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Dossier Filing
Date: 2024-11-14
Procedure: Examination
EPIDOSNEXAM52
Date on which the examining division has become responsible
Procedural Step
Date: 2024-11-14
Procedure: Examination
EXAM52
Amendments
Procedural Step
Date: 2024-11-14
Procedure: Examination
ABEX
Supplementary search report
Dossier Filing
Date: 2024-06-28
Procedure: Examination
0009016
Change - classification
Dossier Filing
Date: 2024-06-27
Procedure: Examination
0008199IPCL
New entry: Observations by third parties
Dossier Filing
Date: 2024-06-11
Procedure: Examination
EPIDOSNTIPA
Observations by a third party
Procedural Step
Date: 2024-06-10
Procedure: Examination
TIPA
Publication in section I.1 EP Bulletin
Dossier Filing
Date: 2023-09-08
Procedure: Examination
0009012
Request for examination filed
Dossier Filing
Date: 2023-09-08
Procedure: Examination
0009171
PCT data prior to European publication
Dossier Filing
Date: 2023-07-11
Procedure: Examination
EPIDOS PCT
Amendment by applicant
Dossier Filing
Date: 2023-07-07
Procedure: Examination
EPIDOS ABEX
PCT data prior to European publication
Dossier Filing
Date: 2023-07-07
Procedure: Examination
EPIDOS PCT
Change - representative
Dossier Filing
Date: 2023-07-05
Procedure: Examination
EPIDOS FREP
PCT data prior to European publication
Dossier Filing
Date: 2023-07-05
Procedure: Examination
EPIDOS PCT
Translation of the application
Procedural Step
Date: 2023-07-05
Procedure: Examination
TRAN
Payment of national basic fee
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Date: 2023-07-05
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FFEE
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Date: 2023-07-05
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Date: 2023-07-05
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DEST
Payment of the fee for examination
Procedural Step
Date: 2023-07-05
Procedure: Examination
EXAM_PCT
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Dossier Filing
Date: 2023-06-16
Procedure: Examination
EPIDOS PCT
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Date: 2023-06-16
Procedure: Examination
EPIDOSNWIAI
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Procedural Step
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VAPT
Extension of the patent
Procedural Step
Procedure: Examination
EXPT
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PROL
International searching authority
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ISAT