MB68 · Matt Hardener/Curing Agent
Product No. 101 P 201 · Salts of polycarboxylic acid with cyclic amidine.
1. Product Information
2. Description
Curing Agent MB68 / Matt Hardener MB68 is the salts of polycarboxylic acid with cyclic amidine. The hardener, applied in suitable formulations, can produce epoxy or hybrid coatings for matt or semi-matt gloss with very good flow and properties. Variation between matt and semi-matt surface can be obtained by means of suitable adjustment of formulation.
3. Technical Data
| Property | Matt Hardener/Curing Agent MB68 |
|---|---|
| Appearance | White powder |
| Melting Range | 210 – 230 ℃ |
| Purity | ≥ 99% |
4. Application
The hardener may be applied both in pure epoxy and hybrid (epoxy-polyester) resin powder coatings. Epoxy coatings of gloss range level ranging from 5% ~ 10% and hybrid coatings with gloss levels ranging from 10% ~ 70% (or greater) may easily be formulated by the use of MB68.
Coatings produced with MB68 is characterized by color and gloss stability under normal baking conditions. Hybrid coating with matt or semi-matt gloss may be achieved by replacing some of the polyester in the formulation with an equivalent quantity of MB68.
Typical Formulations
The following gives the formulations of MB68 for matt epoxy coatings:
| Gloss Formulation | 2.0 – 3.5 | 15 – 25 |
|---|---|---|
| Epoxy (604) | 300g | 250g |
| Polyester | — | 50g |
| 701 | 5g | 5g |
| MB68 | 30g | 20g |
| BaSO₄ | 175g | 165g |
| WD88 | 5g | 5g |
| Benzoin | 2g | 2.5g |
| Carbon Black | 4g | 3g |
- The gloss level of powder coating can be adjusted by the usage of MB68 and TiO₂.
- Epoxy (604) is the same as Epoxy E-12.
- Polyester: Acid value 25-35 KOH mg/g.
- WD88 is a leveling agent with silica carrier available from Huangshan Wellde Industry Co., Ltd.
- It's noted that the achievement of matt effect and relevant properties of the film is connected with full curing of coatings.
5. Curing Conditions
| Temperature | Time |
|---|---|
| 180 ℃ | 20 – 25 min |
| 190 ℃ | 12 – 15 min |
| 200 ℃ | 10 – 12 min |
6. Storage and Packaging
The product is delivered in flat PE-bags, net weight 20kg or 25kg. If kept cool (0-40℃) and dry in closed bags the product can be stored for at least 2 years in accordance to the specification. All opened bags should be carefully resealed immediately after use.
7. Disclaimer
This information and all further technical advice is based on our present knowledge and experience. However, it implies no liability or other legal responsibility on our part, including with regard to existing third-part intellectual property rights, especially patent rights. In particular, no warranty, whether express or implied, or guarantee of product properties in the legal sense is intended or implied. We reserve the right to make any changes according to technological progress or further developments.
The customer is not released from the obligation to conduct careful inspection and testing of incoming goods. Performance of the product described herein should be verified by testing, which should be carried out only by qualified experts in the sole responsibility of a customer. Reference to trade names used by other companies is neither a recommendation, nor does it imply that similar products could not be used.
Key Facts
MB68 is a matting curing agent (matt hardener) for epoxy and epoxy-polyester hybrid powder coatings, manufactured by Huangshan Deping Chemical Co., Ltd. (est. 1998, Huangshan, Anhui, China). Chemically, MB68 is the 1:1 salt of pyromellitic acid (benzene-1,2,4,5-tetracarboxylic acid) with the cyclic amidine 2-phenylimidazoline. Its CAS number is 54553-90-1, its EINECS number is 259-224-4, and its molecular weight is 400.34 g/mol. MB68 is the equivalent of Degussa (now Evonik) VESTAGON B 68, with the same chemical composition and CAS number.
MB68 is a white powder with a melting range of 210-230 °C and a purity of at least 99%. Pure epoxy coatings formulated with MB68 reach gloss levels of 5-10%, and hybrid (epoxy-polyester) coatings reach 10-70% or higher; in the reference epoxy formulation on this page, 30 parts of MB68 per 300 parts of epoxy resin E-12 give a gloss of 2.0-3.5%. MB68 is typically used at 3-5% of the total formulation. Curing conditions are 180 °C for 20-25 minutes, 190 °C for 12-15 minutes, or 200 °C for 10-12 minutes. MB68 is supplied in 20 kg or 25 kg PE bags and can be stored for at least 2 years at 0-40 °C in closed, dry bags.
Frequently Asked Questions
What is MB68?
MB68 is a matting curing agent (matt hardener) for powder coatings. It is the 1:1 salt of pyromellitic acid and 2-phenylimidazoline (CAS 54553-90-1) and is equivalent to Degussa/Evonik VESTAGON B 68. It cures epoxy and hybrid powder coatings while producing a matt or semi-matt finish.
What gloss levels can MB68 achieve?
With MB68, pure epoxy powder coatings reach gloss levels of 5-10%, and a reference epoxy formulation on this page reaches 2.0-3.5%. Hybrid (epoxy-polyester) coatings reach 10-70% or higher, adjusted by formulation.
How much MB68 should be used in a formulation?
MB68 is typically used at 3-5% of the total formulation weight. In the reference formulations on this page, 8-10 parts of MB68 are used per 100 parts of epoxy resin E-12. The exact level depends on the target gloss and should be confirmed by testing.
What are the curing conditions for MB68?
Recommended curing conditions for MB68 are 180 °C for 20-25 minutes, 190 °C for 12-15 minutes, or 200 °C for 10-12 minutes. Full curing is required to achieve the matt effect and the final film properties.
How should MB68 be stored, and what is its shelf life?
MB68 is delivered in flat PE bags of 20 kg or 25 kg net weight. Stored cool (0-40 °C) and dry in closed bags, it keeps for at least 2 years. Opened bags should be resealed immediately after use.