What is the effect of pigment dispersion on coatings

Release time:

2023-08-25 17:25

Source:

In the use of coatings, people often encounter problems such as flocculation, insufficient color or transparency, poor rheology or stability, which are closely related to the insufficient dispersion of pigments.

Purely theoretically, "well dispersed" means that each pigment particle in the system is completely unflocculated, I .e., each pigment particle is wrapped by a thin layer of binder or solvent. In practice, however, this is difficult to achieve. So, what is the effect of pigment dispersion on the performance of the coating?

1. Gloss: If the pigment is optimally dispersed, this can directly increase the gloss. In principle, the gloss is determined by the properties of the binder. The addition of the necessary pigments can only have an adverse effect on the gloss: if the pigments are not optimally dispersed, certain pigment agglomerates will have an adverse effect on the surface flatness, thus reducing the apparent gloss due to diffuse scattering of light.

2, resistance: weather resistance and chemical resistance will also be mainly determined by the choice of paint base. Insufficient dispersion of the pigment particles here also lowers the resistance. Pigment particles protruding from the surface provide points of attack for chemicals and climatic factors. If, on the other hand, the correctly selected pigments are optimally dispersed, it is only possible to improve the resistance of the coating system, for example by improving the weathering resistance by reflection (TiO2) or absorption of ultraviolet radiation (red iron oxide). Suitable pigments or extenders can also improve the chemical resistance of the binder if optimally dispersed.

Storage period: The storage period of the coating system depends to a large extent on the quality of the pigment dispersion. It is easy to understand the adverse effects of precipitation of coarse pigment particles when an excessive ratio of coarse pigment particles is present in the system. Such stability problems are caused either by the so-called "post-wetting" of the pigment, or by the reverse reflocculation of the pigment. Post-wetting can be imparted if the pigment is not fully reflocculated right at the start of dispersion to complete dispersion. The reason for the reflocculation of a previously properly dispersed pigment dispersion is that the stability of the pigment slurry is good enough. This depends to a large extent on the stability of the dispersing binder or the ratio of the binder to the solvent during the dispersion process. Solvents generally have good wetting properties, while the binder is advantageous for stability. The problem is to achieve the desired combination of wetting (= solvent) and stability (= binder).

4. Color, color intensity, transparency and hiding power: all these properties depend to a large extent on the pigment surface used, that is, the "best dispersion". Complete dispersion of the pigment can lead to an increase in the hiding power in the case of covering pigments and to a greater color strength of the toning paste (without flocculation), while in the case of transparent pigments it can lead to a better transparency. For all pigments, complete dispersion of the pigment can result in the full display of the hue and "color purity" of the color.

Previous Page

Water soluble paint

Next Page

A pigment is a substance that causes an object to be colored.

More news

Overview of Water Soluble Coatings and Its Classification

1, with a clean diluent or water will be transferred to the appropriate coating viscosity, the coating -4 viscometer measurement, the appropriate viscosity is generally 18 to 30 seconds. If there is no viscometer at the moment, visual inspection method can be used: stir the coating evenly with a rod (iron rod or wooden rod) and then stop at a height of 20cm for observation. if the paint solution keeps running within a short period of time (a few seconds), it is too thick; If the line is broken from the upper edge of the barrel, it is too thin. When it is stopped at a height of 20cm, the paint solution will form a straight line and drop will instantly cut off, this viscosity is more appropriate.

Glass protection ink

The bottleneck problem of touch glass mentioned by manufacturers is, first of all, environmental protection safety regulations. In recent years, local governments in mainland China have attached great importance to industrial environmental protection issues. Process emissions with serious emissions and heavy pollution are subject to strict supervision, and penalties can be severe enough to order the shutdown of factories. In the past, manufacturers used UV-hardened peelable glue to protect the surface integrity of the glass during the cutting process, but they needed to be soaked and stripped with NaOH strong alkali solution afterwards. Now there is no factory for sewage treatment and discharge. Therefore, Crown Chemical provides manufacturers with a new U2 UV curable surface protection ink, which has good water resistance and scratch resistance. It can be coated with screen printing and then cured with UV light to form a good protective film, which can avoid damaging the precise glass surface during cutting. After the cutting process is completed, soak and strip with Na2CO3 sodium carbonate weak alkali solution. This UV-curable glass cutting protection ink has attracted much attention. In addition to solving the problem of environmental protection in the process, it is also very suitable for stacked glass cutting developed by mainland manufacturers in large-scale production.

Instructions for use of screen glass metal ink

Instructions for the use of glass ink In the four printing methods, silk screen printing is widely used in the printing industry because it is suitable for large color blocks of flat printing and printing effects. In the printing of glass products and glass crafts, screen printing glass ink is the most widely used one. Glass ink adheres to the concept of innovative technology and innovative products, and is recognized by industry insiders and customers in the market. Let's take a look at the instructions for the use of glass ink.

Water soluble paint

Overview of Water Soluble Coatings and Its Classification Core Tip: Water-soluble coating is a kind of coating made of water-soluble synthetic resin as the main film-forming substance, water as diluent, adding appropriate amount of pigment, filler and auxiliary materials, etc. Water-soluble coatings have formed a multi-variety, multi-functional, multi-purpose, large and complete system. Water-soluble coating is a water-soluble synthetic resin as the main film-forming material, water as diluent, adding the right amount of pigments, fillers and auxiliary materials, etc., after grinding a coating. Water-soluble coatings have formed a multi-variety, multi-functional, multi-purpose, large and complete system.

What is the effect of pigment dispersion on coatings

In the use of coatings, people often encounter problems such as flocculation, insufficient color or transparency, poor rheology or stability, which are closely related to the insufficient dispersion of pigments. Purely theoretically, "well dispersed" means that each pigment particle in the system is completely unflocculated, I .e., each pigment particle is wrapped by a thin layer of binder or solvent. In practice, however, this is difficult to achieve. So, what is the effect of pigment dispersion on the performance of the coating?

A pigment is a substance that causes an object to be colored.

A pigment is a substance that colors an object. Pigments are soluble and insoluble, and there are differences between inorganic and organic. Inorganic pigments are generally mineral substances, humans have long known the use of inorganic pigments, the use of colored soil and ore, in the rock wall painting and daub the body. Organic pigments are generally taken from plants and marine animals, such as aziline, gambogia and the ancient Roman purple extracted from shellfish.