Naphthenic base oil

Union Sekiyu Kogyo Co., Ltd (collectively “Union”), partially owned by the two largest refineries Eneos and Idemitsu, is one of the only two naphthenic base oil manufacturers in Japan.

Founded in 1947, at Iwakuni, Yamaguchi prefecture, Union has grown into a leading supplier for multiple industries.

Known for its higher solubility and lower pour point compared to the paraffinic base oil, Union’s naphthenic base oil has been widely used in adhesives, compressor oils, gear oils, greases, insulating oils, paints and coatings, process oils or transformer oils.  


For decades,  Hanwa Co., Ltd has been in partnership with Union, serving as its distributor, both in and outside Japan.

Both companies are now setting our sights on expanding the export volume of naphthenic base oil, in a bid to tackle the issue of the decreasing and inconsistent supply across Asia over the recent years.


We believe with Hanwa’s extensive sales network coverage and deep expertise in the industry, we can offer tailor-made solution to your requirements.

Please contact here for enquiries. 




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