Account
Please wait, authorizing ...

Do you have an account? Create one now.

×

Powder paints for wood

The author mentions the current trends in application and curing of this type of coatings on these substrates. Carlos Agredo Gamboni wrote to our email [email protected] raising the following concern:

by Hugo A. Haas

I would like to see an article that contemplates the state of development of wood dust (MDF, HDF) in Latin America; such as: Progress in the development of resin, contacts for the acquisition of IR oven for both plants and laboratory, types of paint, prices of this paint in the market, etc.

We consulted the opinion of Hugo A. Haas of the Argentine formulation company Pulverlux S.A. and this is what he answered us.

The market for powder coatings for wood is developing rapidly based on the undeniable advantages of application, costs and performance of these materials. It is a very efficient substitute for plastic laminates allowing the simultaneous painting of the edges. Bathroom furniture, kitchens, desks, office furniture, club cabinets, hospital equipment, etc.

- Publicidad -

As is well known, powder coatings have had an enormous development and are generally widely used in the metalworking industry in which metal substrates conduct electricity and resist curing temperatures of around 200 °C.

This characteristic is not precisely met in substrates such as wood and its derivatives or thermoplastics or papers, cardboard, plastic flooring etc.

Technological development has taken two basic directions, which are, namely:

1.Powder paints of the conventional type (hybrids, polyesters, epoxies). cured in convection ovens at temperatures of the order of 120 to 140 °C.
2.Powder paints that cure by a mixed process of red (IR) and ultraviolet (UV) infrared radiation.

Conventional paints
They are produced in all colors, shines and textures in qualities of hybrids (epoxy-polyester), pure polyesters (cured with TGIC or Primid) and epoxy cured with different belting agents.

The paints chemically and mechanically resist a wide variety of agents used in bathrooms, kitchens etc., such as solvents, detergents, cleaners, aerosols, perfumes, etc. As well as behave excellently in all abrasion requests, blows etc.

They are applied with electrostatic equipment by Corona process and cured in conventional convection furnaces heated by hot air, gas or electricity at temperatures ranging between 120 and 140 °C.

- Publicidad -

The painting process goes through the following stages:

Preparation of the surface by sanding with fine sandpaper that leaves the surface as free of defects.

Optional application for woods and derivatives of a sandable aqueous bottom, which cures in the air or in the oven at low temperature. In many cases this background is not necessary to apply, especially when the finishes that are sought are of little brightness or with textures. It is very convenient when you want shiny surfaces. On the other hand, it is essential to use a special conductive background when you want to paint thermoplastic materials.

Preheating of the piece of wood to about 100 ° C and application on it in hot, of the chosen powder paint, with thicknesses ranging between 60 and 100 micrometers.

Baking of the painted pieces for 20-40 minutes at temperatures of 120 to 140 °C.


Combination curable paints
This is a field of a great future but it is conditioned to the client owning the corresponding curing installation, which because it is expensive, still limits the use of this technology.

- Publicidad -

The system is based on formulations with special unsaturated polyesters containing photoinitiators that are the ones that cause the curing reaction through the entire paint film and in very short times.

The polyester resins used generally have very low TG so the stability of the powders in the boxes in which they are provided requires storage in cold or cooled tanks to avoid the caking of the powders, and in addition, the footoiniciators are of such a characteristic that they do not release residual products (such as benzaldehyde) and do not produce yellowing or color changes of the paints.

The painting process goes through the following stages:

Preparation of the substrate so as not to present imperfections.

Application of paint by conventional crown process.

Passage through an installation in which it is first subjected to the action of IR lamps, which melt the paint with which it levels and extends over the substrate, and immediate passage under UV lamps of pre-studied wavelength radiation (mercury or iron), for a few seconds, with which the material comes out perfectly cured and chemically and mechanically resistant.

It should be noted that the result of the system depends a lot on the color that is applied since there may be inconveniences of reception of UV radiations (for example in titanium dioxide it must be exclusively rutile, since the anatase interferes with the photocatalytic action) and also the shape of the objects to be painted must be such that there are no shadows that prevent certain areas of the object to be painted from being cured. They can be manufactured in various shines and textures.

Author: Vanesa Restrepo

No thoughts on “Powder paints for wood”

• If you're already registered, please log in first. Your email will not be published.

Leave your comment

In reply to Some User
Suscribase Gratis
SUBSCRIBE TO OUR ENGLISH LANGUAGE NEWSLETTER
DO YOU NEED A PRODUCT QUOTE?
HIGHLIGHTED INTERVIEWS

Entrevista con Sergio Zárate de Lanxess

Entrevista con Sergio Zárate Empresa: Lanxess Realizada por Ana María Mejía Evento: LACS 2019 - México Junio 2019

Entrevista con Roberto Barrera de Lubrizol

Entrevista con Roberto Barrera Empresa: Lubrizol Realizada por Ana María Mejía Evento: LACS 2019 - México Junio 2019

Entrevista con Miguel Ángel Castillo de Evonik

Entrevista con Miguel Ángel Castillo Empresa: Evonik Realizada por Ana María Mejía Evento: LACS 2019 - México Junio 2019

Entrevista con Marcos Basso de Eastman

Entrevista con Marcos Basso Empresa: Eastman Realizada por Ana María Mejía Evento: LACS 2019 - México Junio 2019

Entrevista con Juan Carlos Orozco de DOW

Entrevista con Juan Carlos Orozco Empresa: DOW Realizada por Ana María Mejía Evento: LACS 2019 - México Junio 2019
Load more...
SITE SPONSORS










LATEST NEWSLETTER
Ultimo Info-Boletin