(19) (12) EUROPEAN PATENT APPLICATION (11) EP 3 800 003 A1 (43) Date of publication:  07.04.2021 Bulletin 2021/14 (51) Int Cl.: B23K 35/36 (2006.01) (21) Application number:  20197630.5 (22) Date of filing:  23.09.2020 (84) Designated Contracting 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 Designated Extension States:  BA ME Designated Validation States:  KH MA MD TN (30) Priority: 03.10.2019 JP 2019182995 (71) Applicant:  SENJU METAL INDUSTRY CO., LTD. Tokyo, 120-8555 (JP) (72) Inventor:  MIZOWAKI, Toshio Tokyo, 1208555 (JP) (74) Representative:  AWA Sweden AB Junkersgatan 1 582 35 Linköping (SE) (54) ROSIN MODIFIED PRODUCT, FLUX COMPOSITION, LIQUID FLUX, FLUX CORED SOLDER  AND SOLDER PASTE (57) A rosin-modified product being a reactant of a rosin or a rosin derivative and an alkanolamine represented by a following Formula (1) or being produced by a reaction of a rosin or a rosin derivative, an organic acid and an alkanolamine. Printed by Jouve, 75001 PARIS (FR) EP 800 003 A1  (1) NH$_{3-n}$-(R-OH)$_{n}$ (n  ≤ 3) ;