Company Information


DJK’s main activities are below services related to polymeric materials and composite materials.

  1. Synthesis, polymerization, and reforming action.
  2. Compounding, molding, and processing samples.
  3. Material testing, physical properties measurement, and analyzing.
  4. Defect analysis of products.
  5. Applying and testing various standard test (FDA/EPA, CSA, etc).

Company Overview

Company Name DJK Corporation
Company Address 2-7-17 Shinyokohama, Kouhoku-ku, Yokohama, 222-0033 Japan
Date Founded December, 1981
Capital 100 Million Yen
President Toshinori Iwai
Number of Employees 109

Information of December, 2022

Company History

February 1964 Dainihon Jyushi Kenkyujyo (now Yokohama Laboratories) established
July 1971 Oversea section of Dainihon Jyushi Kenkyujyo has been separated and becomes DJK International Corporation (now Shin-Yokohama Office)
December 1981 DJK Research Center (now Chiba Technical Center) established
February 2001 Dainihon Jyushi Kenkyujyo changes company name to DJK Kenkyujyo
November 2003 DJK Kenkyujyo moves to Tsuzuki-ku, Yokohama
September 2004 DJK Research Center and DJK Kenkyujyo merged to form DJK Corporation
December 2005 DJK Corporation and DJK International merged
June 2009 New laboratory building completed in Chiba Technical Center
December 2013 Capital increase to 100 Million Yen
October 2014 Nagoya Laboratories established
October 2016 Polymer Processing Technology Laboratory established
February 2019 Headquarter relocated in Kouhoku-ku, Yokohama
November 2019 Shin-Yokohama Office relocated in Kouhoku-ku, Yokohama
July 2022 Central Laboratory established
December 2022 Polymer Fusion Technology Laboratory relocated in Moriyama-ku, Nagoya

Quality Control Activity

ISO9001 Quality Management System
Office Yokohama Laboratories Chiba Technical Center Nagoya Laboratories
Registered Number JQA-QMA12453
Examining Authority Japan Quality Assurance Organization
Registered Date October 2005 December 2012 October 2015
ISO17025 Quality Management System (for testing laboratories)
Office Chiba Technical Center
Registered Number RTL01110
Examining Authority Japan Accreditation Board
Registered Date June 2002
Testing Category Mechanical properties of polymeric materials (tensile strength and combustion test)
ISO17025 Quality Management System (for testing laboratories)
Office Yokohama Laboratories
Registered Number RTL02820
Examining Authority Japan Accreditation Board
Registered Date March 2009
Testing Category Chemical test / analysis of toxic substance
Analytical Method Acid decomposition method in sealed container – Inductively coupled plasma mass spectroscopy
Quartz tube combustion – Ion chromatography
Target material Cadmium, lead, total chromium, mercury
Total boromine