Matting of high-solids coatings
Environmental restrictions challenge the varnish manufacturer to find new ways to reduce the shares of organic solvents in their formulations. One possibility to realize products in accordance to these restrictions is the formulation of high-solids, in which the shares of volatile organic compounds have been reduced or removed.
In conventional coating systems, the matting by means of porous silica particles is dependent on the shrinkage of the film due to solvent evaporation during the drying process.
In high-solids systems, the matting is more difficult because there is hardly any shrinkage during film formation. In this case, the formation of a micro-rough surface depends i. a. on viscoelastic forces which appeal during the film formation on the matte particles.
The matting agents of the PS-Matt series have been specifically developed by Pigmentsolution with the aim to provide an optimal interaction with the viscoelastic forces occurring during the film formation phase, whereby the matting is positively influenced.
By this operation, PS-Matt products are able to generate an excellent matting effect.
Benefits:
In conventional coating systems, the matting by means of porous silica particles is dependent on the shrinkage of the film due to solvent evaporation during the drying process.
In high-solids systems, the matting is more difficult because there is hardly any shrinkage during film formation. In this case, the formation of a micro-rough surface depends i. a. on viscoelastic forces which appeal during the film formation on the matte particles.
The matting agents of the PS-Matt series have been specifically developed by Pigmentsolution with the aim to provide an optimal interaction with the viscoelastic forces occurring during the film formation phase, whereby the matting is positively influenced.
By this operation, PS-Matt products are able to generate an excellent matting effect.
Benefits:
- high shear stability, grinding constancy
- no formation of hard sediment during storage
- no influence on the curing
- no impairment of the inter-layer adhesion
- abrasion-resistant films of high surface quality
- no fogging
- minimal effect on the mechanical film properties , such as hardness or flexibility
- minimal effect on the weathering resistance
Matting of water-thinnable systems
The matting mechanism of waterborne dispersions is similar to the matting mechanism of systems based on solvents.
Due to the relatively high proportion of volatile constituents, the coating film shrinks quite considerably during the drying and thus forms the required micro-rough surface structure for the light scattering and the dulling effect. With the help of highly effective PS-Matt systems high quality and haze-free surfaces with low gloss values can be achieved.
The range of PS-Matt W portfolio was developed specifically for the matting of water-reducible coatings. Because of their exceptional product features PS-Matt W systems should always be used when the focus is on the incorporation and handling of the matting agent.
Benefits:
Due to the relatively high proportion of volatile constituents, the coating film shrinks quite considerably during the drying and thus forms the required micro-rough surface structure for the light scattering and the dulling effect. With the help of highly effective PS-Matt systems high quality and haze-free surfaces with low gloss values can be achieved.
The range of PS-Matt W portfolio was developed specifically for the matting of water-reducible coatings. Because of their exceptional product features PS-Matt W systems should always be used when the focus is on the incorporation and handling of the matting agent.
Benefits:
- low dust development
- reduced wetting time
- less foaming
- prevents coagulation of the binder
PS matt 601
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PS matt 112
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x 500 x 1000 x 3500 |
PS-Matting agents
PS-Matting agents are suitable for:
- Furniture and parquet varnishes
- UV industry
- Paint Industry
- Printing inks
Requirements for ma/ng agents
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Brief description and characteristics
a) Precipitated silica:
Quality control
The production control of the PS-MaK products takes place during production. The quality
assurance is carried out on each batch not only by the determination of the releasable
chemical-physical data, but also application-specific properties are tested in different
lacquer systems such as:
assurance is carried out on each batch not only by the determination of the releasable
chemical-physical data, but also application-specific properties are tested in different
lacquer systems such as:
- wetting
- dispersibility
- flow behaviour
- suspension behaviour
- matting
- transparency
- surface
Physical and chemical characteristics
1 Based on the original material
2 Based on the dry substance (2 h/105°C)
3 Based on the annealed material (2 h/1000°C)
** Depending on concentration and coating System
2 Based on the dry substance (2 h/105°C)
3 Based on the annealed material (2 h/1000°C)
** Depending on concentration and coating System
Application
* OPV = over pressure varnishes
Systems
Layer thickness
The practitioner is aware that thicker lacquer layers are generally more difficult to matt. A dry lacquer film thickness results from the thickness of the applied wet film and the solids content of the lacquer. The lower the layer thickness of the dry lacquer film is, the more matting agent particles become effective on the surface and the lacquer film surface appears to be matte. However, the higher the solids content of a varnish and thus the dry film thickness of a varnish, the more the matting agent particles have the possibility to arrange themselves energetically favourably at the same concentration in the varnish. Thus, they are not effective for the roughening of the surface, the paint film appears more brilliant. To adjust an equivalent matting degree, a greater amount of matting agent is required. This is especially true for systems with a solids content of> 70%.
Product safety
Synthetic amorphous silicas and their surface-treated variants do not contain any crystalline constituents. X-ray diffraction, high-resolution transmission electron microscopy and electron diffraction are used as the determination methods. The detection limit of these methods is less than 0.05% by weight. In addition, transmission electron microscopy offers the possibility to determine solid-state structures up to a dimension of 0.5 nanometers. On the basis of the present results PS-Matt can be described as completely amorphous.
9.1 Toxicology
From decades of experience, it is known that the use of PS-Matt does not lead to any health damage.
The acute toxicity of synthetic amorphous silica, rat orally, LD50, is above 5,000 mg / kg. PS-Matt does not irritate the skin and eyes.
9.1 Toxicology
From decades of experience, it is known that the use of PS-Matt does not lead to any health damage.
The acute toxicity of synthetic amorphous silica, rat orally, LD50, is above 5,000 mg / kg. PS-Matt does not irritate the skin and eyes.
