Solutions for “Very High Solid” polyurethane coatings

High Solid coatings with polyaspartics

Polyaspartic acids (Polyaspartics) can be used for the formulation of very high solid coatings. Polyaspartics are not blocked, they are odorless, have a low color value and are compatible with most other resins. Due to their aliphatic character the coatings exhibit good weatherability and excellent corrosion protection. This technology shows above average growth and is primarily used in coatings for corrosion protection, for commercial vehicles, ACE (Agricultural, Construction, Earth Moving Equipment), in windmill power plants and in the construction industry. In summary the most important properties of polyaspartics:

• Fast cure
• Low VOC
• Rapid film building
• High film build in one pass
• Excellent corrosion protection

Polyaspartic acids are cured with aliphatic polyisocyanates. The potlife and reactivity of the formulation can exactly be finetuned by selecting the appropriate Desmophen® NH component.

Product examples of Polyaspartics:

	Solids in %	Equivalent weight	Viscosity mPas at 25°C	Reactivity
Desmophen® NH 1520	100	290	~ 1200	+
Desmophen® NH 1420	100	279	~ 1500	++
Desmophen® NH 1220	100	230	< 100	++++
Desmophen® NH 1521	90 % in BA	326	~ 150	+

Some suitable polyisocyanate crosslinker (Examples)

	Solids in %	Viscosity mPas at 23°C	NCO-Content [%]	Functionality
Desmodur® N 3900	100	700	23,7	> 3
Desmodur® N 3600	100	1200	23	> 3
Desmodur® N 3390 BA	90 in Butylacetat	500	19,6	> 3
Desmodur® N 75 BA	75 in Butylacetat	170	16,5	> 3

Get more information on polyaspartics here:

Article in Surface Coating International Magazine, Issue 2009/x:
"Polyaspartics - innovative binders for cost-effective coating design"

Presentation:
"Polyaspartics - Modern Binders for highly efficient 2K PUR Systems"

More information - "Höhere Produktivität beim Lackieren" - here (german)


High Solids with acrylate monomers

Aminofunctional acrylate monomers can be used for the production of fast curing high solids and very high solids two-component polyurethane coatings systems.

The implementation of the new European VOC regulations requires innovative solutions in low solvent coating formulations. Ketimines like Desmophen® LS 2965 A and aldemines like Desmophen® VP LS 2142 are coating raw materials, which show a low viscosity combined with a high reactivity vs. polyisocyanates and which can therefore be used as reactive thinners. The use of reactive thinners does not require the high amount of solvents usually needed for this kind of application in order to obtain low viscosity. Less than 250g/l VOC are sufficient to obtain the suitable viscosity.

Product examples of reactive solvents

	Solids content in %	Equivalent Weight	Viscosity mPas at 25°C	Reactivity
Desmophen® VP LS 2142 (Diamine)	100	139	~ 25	++
Desmophen® LS 2965A (Ketimine)	100	167	~ 80	++(+)