Dongsen Chemicals — A Polyisocyanate Curing Agent Manufacturer Since 1988
Updated: 2026
Dongsen Chemicals — A Polyisocyanate Curing Agent Manufacturer Since 1988
Request TDS Request Sample Request Quotation Ask for a Suitable Grade
Quick answer: Dongsen is a Chinese manufacturer of polyisocyanate curing agents and crosslinkers — not a paint producer. Founded in 1988, Dongsen supplies aromatic, aliphatic, solvent-based blocked, waterborne, and moisture-curing isocyanate hardeners to coating and adhesive formulators worldwide.
Who is Dongsen?
Dongsen is an upstream raw-material manufacturer: we make the polyisocyanate curing agents and crosslinkers that coating and adhesive producers add to their own resin systems. We are not a paint brand and do not sell finished coatings — our hardeners are used to formulate PU wood finishes, automotive coatings, industrial and anti-corrosion coatings, floor coatings, and laminating adhesives.
That distinction matters for buyers. Whatever carrier or system a formulator runs — solvent-based or waterborne, 2K or 1K bake — the crosslinker is the component that decides yellowing resistance, chemical resistance, and crosslink density. Dongsen's entire business is built around getting that one variable right.
A heritage built on curing agents since 1988
Dongsen traces its roots to 1988, when the business began in polyurethane raw materials. Over more than three decades it grew from raw-material trading into integrated R&D, manufacturing, and application service focused on isocyanate curing agents.
Today that capability is concentrated at a purpose-built manufacturing base in Shaoguan, China, constructed to the current national fine-chemical standard. In 2024 the group consolidated its curing-agent capacity at this base and launched a digital-factory upgrade — a shift that gives overseas customers a single, traceable, modern production source rather than scattered legacy lines. You can read more on the Dongsen history page.
What Dongsen manufactures
Dongsen produces a full line of isocyanate hardeners across solvent-based, waterborne, and functional chemistries. The table below maps each series to its chemistry and typical formulation direction.
| Curing-agent series | Chemistry / character | Typical use direction |
|---|---|---|
| Aromatic polyisocyanate | TDI adduct / trimer — high reactivity, economical | Indoor wood & furniture, general industrial |
| Aliphatic polyisocyanate | HDI biuret / trimer — non-yellowing, weather-resistant | Automotive refinish, exterior & UV-exposed systems |
| Solvent-based blocked | Heat-released NCO — controlled deblocking temperature | 1K bake coatings, coil & can, wire enamel |
| Waterborne (dispersible / soluble) | Hydrophilically modified polyisocyanate | Low-VOC 2K waterborne wood & industrial coatings |
| Moisture-curing | NCO-terminated prepolymer | 1K moisture-cure primers & topcoats |
Takeaway: the non-yellowing, weather-resistant behaviour buyers want for exterior and automotive work comes from aliphatic (HDI) chemistry, not from whether the system is water- or solvent-borne — and selecting the right hardener is what locks that performance in.
Why formulators work with Dongsen
Dongsen is a licensed chemical manufacturer (a producer, not a trader) and part of a polyurethane-materials group founded in 1988, with around 150,000 m² of production area, 25+ patents, and exports to 40+ countries. Its curing agents are produced at a dedicated, digitally controlled base in Shaoguan, China, with a design capacity of 26,000 tonnes per year. Credibility signals overseas buyers can verify:
- Internationally recognized quality & environmental systems — certified to ISO 9001:2015 and ISO 14001:2015 by ACM International Certification under IAF mutual recognition (valid to 4 Aug 2028). The certified scope explicitly covers low-free-monomer, high-solid curing agents.
- National High-Tech Enterprise (Cert. No. GR202444002848), corroborating sustained R&D investment and a 25+ patent portfolio.
- Dedicated R&D directions — low-free-monomer curing agents, 80°C low-temperature deblocking grades, and low-odor chemistries, backed by R&D and application labs.
These certifications are quality and management-system credentials. They are separate from product chemical-registration status, which we confirm per market on request.
Serving customers worldwide
Dongsen supplies coating, adhesive, and ink formulators internationally — across Southeast Asia, Latin America, and other markets. EU/EEA customers are welcome to request samples and submit technical inquiries; note that the EU enforces mandatory diisocyanate training and labelling requirements for handling. Tell us your market and application, and we will confirm the right grade, documentation, and supply path for your region.
Ready to evaluate a Dongsen hardener?
If you are dealing with any of the following, a grade change is usually the fastest fix:
- Films that yellow under UV or exterior exposure
- Poor compatibility or viscosity build in waterborne systems
- Bake windows that need a lower deblocking temperature
Request TDS Request Sample Request Quotation Go to Inquiry Form
Talk to Dongsen’s technical team
- 🧪 Free sample screening for your resin system
- 📄 Up-to-date TDS & COA for every grade
- 🌍 Export support and per-market documentation
- ⚙️ Grade selection advice from our application lab
- ⏱️ Fast response from overseas technical support
Frequently asked questions
Does Dongsen make finished paint?
No. Dongsen manufactures polyisocyanate curing agents and crosslinkers only. These are raw materials added to a formulator's own resin to build coatings and adhesives; Dongsen does not produce or sell finished paint.
What types of isocyanate hardeners does Dongsen produce?
Aromatic (TDI adduct/trimer), aliphatic (HDI biuret/trimer), solvent-based blocked, waterborne dispersible/soluble, and moisture-curing polyisocyanates.
When was Dongsen founded?
Dongsen's polyurethane raw-material business was founded in 1988, giving it more than 38 years of curing-agent experience.
Where are Dongsen’s products made?
At a dedicated, digitally controlled curing-agent manufacturing base in Shaoguan, China, built to the current national fine-chemical standard.
Is Dongsen certified?
Yes — its quality and environmental systems are certified to ISO 9001:2015 and ISO 14001:2015 under IAF mutual recognition, and Dongsen is a recognized National High-Tech Enterprise.
Can Dongsen supply my country?
Dongsen exports to 40+ countries, serving wood & furniture, automotive OEM & refinish, and other applications. Share your market and application and the team will confirm the right grade, documentation, and supply path for your region.
How do I get a sample or quotation?
Use the inquiry form above, email marketing@dongsenchem.com, or message the team on WhatsApp at +86 15361757135.
Key takeaways
- Dongsen is an upstream polyisocyanate curing agent / crosslinker manufacturer, founded 1988 — not a paint producer.
- Full line across aromatic, aliphatic, blocked, waterborne, and moisture-curing chemistries.
- Non-yellowing performance comes from aliphatic (HDI) chemistry — choosing the right hardener locks it in.
- Group founded 1988 — 150,000 m² production, 25+ patents, 40+ export countries; curing agents from a dedicated 26,000 t/yr Shaoguan base. ISO 9001/14001 (IAF) and National High-Tech Enterprise.
- Samples, TDS/COA, and per-market support available on request worldwide.
About Dongsen
Dongsen is a polyisocyanate curing-agent and crosslinker manufacturer based in Shaoguan, China, supplying isocyanate hardeners for coatings and adhesives to formulators in 40+ countries since 1988. Learn more on the company overview or explore the isocyanate hardener range. Related reading: waterborne polyisocyanate hardener for 2K PU coatings and the TDI trimer hardener wood-coating selection guide.
About the author — Vicky Zhao
Overseas Technical Support, Dongsen. Vicky works with international coating and adhesive formulators on waterbased and blocked polyisocyanate crosslinker selection, sample screening, and application troubleshooting. Connect on LinkedIn.
All values are typical and subject to the current TDS/COA.