| Titre : |
Additives for powder coatings |
| Type de document : |
texte imprimé |
| Auteurs : |
Robertino Chinellato, Auteur |
| Année de publication : |
2021 |
| Article en page(s) : |
p. 15-18 |
| Note générale : |
Bibliogr. |
| Langues : |
Anglais (eng) |
| Catégories : |
Catalyseurs
Charges (matériaux)
Polymères
Revêtement poudre -- Additifs
Revêtements organiques
Rhéologie
Tribologie (technologie)
|
| Index. décimale : |
667.9 Revêtements et enduits |
| Résumé : |
In the world of resins and related paints, which is not an exact science, the role of additives and special products is extremely important to obtain special characteristics that often are a fundamental requirement of paints for meeting predefined technical specifications or to meet the needs of end users. In fact, paints that normally play an aesthetic role in improving a product's appearance, also provide mechanical or chemical resistance to environmental stress. As an example, we can mention paints for household appliances or those for aluminium frames, two cases where the satisfaction of technical specifications is a necessary requirement for approval in the end market.
By definition, additives are added in small quantities, often less than one point percent, to reinforce selected chemical or physical properties of the finished paint. The powder coatings sector is no exception and has some limitations that are intrinsic to the technology itself and these are linked to the physical state of the paint before application on the piece to be painted. A peculiar example is the so-called "orange peel" which sometimes distinguishes the final appearance of powder coatings compared to more conventional liquid coatings. This is due to the fact that the powder paint particles must first melt (melting), then aggregate to form a homogeneous liquid film (flow) and finally crosslink to form the final coating film (crosslinking).
Therefore, additives used as flow promoters play an important role in powder coating technology. Flow promoters are additives that allow the paint film to wet the substrate homogeneously during the melting phase of the powder paint and then reduce the orange peel effect during the crosslinking phase.
Surface tension is the parameter that regulates the wettability of the substrate ; a low surface tension implies high wettability of the substrate. |
| Note de contenu : |
- Other special products for powder coatings
- Table 1 : Two types of flow promoters in the powder coatings sector
- Table 2 : Catalysts used in powder coatings
- Table 3 : Tribocharging measurements
- Table 4 : Products used to create special effects |
| En ligne : |
https://drive.google.com/file/d/1P0TPCrpidMIZUIc3Yaz1IY1Q9YR3PFTI/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=36766 |
in POLYMERS PAINT COLOUR JOURNAL - PPCJ > Vol. 211, N° 4669 (06/2021) . - p. 15-18
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Additives for powder coatings in POLYMERS PAINT COLOUR JOURNAL - PPCJ, Vol. 211, N° 4669 (06/2021)
