INTRODUCTION TO ALKYD MELAMINE

1. Introduction

Melamine alkyd paint is made of two types of film-forming agents which are melamine-formaldehyde resin and alkyd resin. Melamine alkyd paint is a chemically dry paint, the paint film will dry under the influence of temperature (from 110°C to 130°C) or weak acid catalyst.

In addition to alkyd resin, other resins such as acrylic resin, epoxy... can be mixed with melamine-formaldehyde resin to make dry paint. Another type of film-forming agent similar to melamine-formaldehyde resin is urea-formaldehyde resin, which is also commonly used to mix with alkyd resins, acrylics, etc make acid-catalyzed or drying paints. Melamine and urea-formaldehyde are called amino resins.

Paint products can be classified into 5 kinds of paint based on their types of resin:

- Alkyd Melamine Paint: formaldehyde melamine resin mixed with alkyd resin

- Acrylic Melamine Paint: melamine resin mixed with thermosetting acrylic resin

- Epoxy melamine paint: melamine resin mixed with epoxy resin

- Alkyd urea paint: urea-formaldehyde resin mixed with alkyd resin, this type can be cured by temperature or by weak acid.

- Mixed paint: melamine/urea resin mixed with more than one alkyd, epoxy, alkyd resin...

If classified based on the dry process, we have two types of paint

- Dry paint

- Acid dry paint (usually urea resin is used)

>> Click HERE for the best paint chemicals on the market<<

2. Raw material for film-forming agents for alkyd melamine paint

2.1. Some feature of melamine-formaldehyde resin

- Quick-drying.

- Alkali and soap resistant.

- Heat tolerance

- Anti-wrinkle

- High gloss and good flowability.

- The content of amino resins on the total resin solids is low.

- Weather-resistant

- Harder paint film 

- Melamine paint with outstanding heat and weather resistance properties is suitable for topcoats and is especially suitable for use in multi-layer paints.

2.2. Film-forming agent mixed with melamine

The most common types of film-forming agents used to mix with melamine are alkyd resins. and acrylics, also, epoxy, alkyd styrene, and polyester are commonly used. Each combination will give us a type of paint with different features. In this article, we only mention Alkyd resin.

Alkyd resin

Alkyd resin is a film-forming agent produced through the poly-accumulation process of a multifunctional acid or their anhydrides such as phthalic anhydride, isophthalic, etc, with polyfunctional alcohol such as pentaerythritol, trimethylolpropane. 

Alkyd resins are made from alcohol. and acid cannot be used to produce paint because of some disadvantages such as low solubility and incompatibility. To produce paint, we have to modify it with oil (herbal oil, animal oil) or fatty acid-derived oil. Besides the polyfunctional acids and polyfunctional alcohols used in the production of alkyd resins, the nature of the oil and the content of modified oil also has a strong influence on the performance of the resin and the final paint film. The oil content calculated by the mass of oil in the resin is called the fat content of the alkyd resin. Based on the fat (oil content) people divide alkyd resin into types:

- Thin Alkyd

- Medium Alkyd

- Fat Alkyd

With the increase of oil content in alkyd resin, the solid content, solubility, ease of processing, flexibility, water resistance, storage durability also increase. Meanwhile, the viscosity, gloss, hardness, oil resistance, colorfastness reduces with the increase of resin fat. The dryness and adhesion of alkyd resins will be optimal when the oil content is about 50-55%, while the weather resistance of alkyd resins is best when the fat content is 65%.

To add some special features to alkyd resin, besides using oil, people can also modify it with other resins:

- Modification with phenol: improve water stability and alkali resistance.

- Modified with turpentine

- Modified vinyl: improve weather resistance, hardness, water resistance, and alkali resistance.

- Modification of silicon

- Modification of epoxy

- Modification of acrylic

- Modification of styrene

- Modification of urethane

- Benzoic denaturation

>>>Read more: Indoor 2K PU wood paint production technology <<<

Alkyd resin is the most commonly used in the paint industry, it can be used in coating many types of surface materials such as metal, wood, for indoor and outdoor. Can be used alone or mixed with many other film-forming agents such as amino, chlorinated rubber, nitrocellulose, silicon.

Alkyd resins are the most common film-forming agents used to mix with melamine (and other amino resins) to make drying coatings. The selection of alkyd resins to mix with melamine in particular an amino resins, in general, must satisfy the following factors:

- Compatible with melamine resin (amino).

- Have a low acid index to prevent self-curing of heat-drying amino paints.

- Enough functional groups to act as hydroxyl groups.

- Be color-durable.

The most suitable alkyd resin for mixing with amino resin is the thin alkyd. Just like amino resins, the starting materials for the production of alkyd resins also influence the film properties and thus influence the selection in a particular field.

Some other film-forming agents

In addition to alkyd, acrylic and epoxy resins are commonly used, too. These film-forming agents can be used alone or in combination or with alkyd resins to obtain a coating with some better performance. For acrylic resin to mix with amino, a thermosetting resin with a reasonable hydroxyl amount must be used. As for epoxy resin, it must have a not-too-large molecular weight to be compatible with other amino.

Above is the introduction to Alkyd Melamine paint materials. For more detailed information please contact us.

>>Click HERE to get advice on transferring Alkyd paint production technology <<

Contact

MEGA VIETNAM

Office address: Floor 2-A2-IA20, Nam Thang Long Urban Area, Pham Van Dong Street,

Dong Ngac Ward, Bac Tu Liem District, Hanoi City, Vietnam

Tel: (+84) 24 375 89089; Fax: (+84) 24 375 89 098

Website: megavietnam.vn

Hotline: 1800.577.728 Zalo: 0971.023.523