What’s Pigment and Its Physical Basis?

A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.

For industrial applications, as well as in the arts, permanence and stability are desirable properties. Pigments that are not permanent are called fugitive. Fugitive pigments fade over time, or with exposure to light, while some eventually blacken.

You don’t just find pigments for paint, but also for coloring ink, plastic, fabric, cosmetics, food, and other materials. Most pigments used in manufacturing and the visual arts are dry colorants, usually ground into a fine powder. This powder is added to a binder (or vehicle), a relatively neutral or colorless material that suspends the pigment and gives the paint its adhesion.

Pigments appear the colors they are because they selectively reflect and absorb certain wavelengths of visible light. White light is a roughly equal mixture of the entire spectrum of visible light with a wavelength in a range from about 375 or 400 nanometers to about 760 or 780 nm. When this light encounters a pigment, parts of the spectrum are absorbed by the molecules or ions of the pigment. In organic pigments such as diazo or phthalocyanine compounds the light is absorbed by the conjugated systems of double bonds in the molecule.

The appearance of pigment for coating is intimately connected to the color of the source light. Sunlight has a high color temperature, and a fairly uniform spectrum, and is considered a standard for white light. Artificial light sources tend to have great peaks in some parts of their spectrum, and deep valleys in others. Viewed under these conditions, pigments will appear different colors.

Naturally occurring pigments such as ochres and iron oxides have been used as colorants since prehistoric times. Archaeologists have uncovered evidence that early humans used paint for aesthetic purposes such as body decoration.

Before the development of synthetic pigments, and the refinement of techniques for extracting mineral pigments, batches of color were often inconsistent. With the development of a modern color industry, manufacturers and professionals have cooperated to create international standards for identifying, producing, measuring, and testing colors.

Selection of a pigment for a particular application is determined by cost, and by the physical properties and attributes of the pigment itself. For example, a pigment that is used to color glass must have very high heat stability in order to survive the manufacturing process; but, suspended in the glass vehicle, its resistance to alkali or acidic materials is not an issue. In artistic paint, heat stability is less important, while lightfastness and toxicity are greater concerns.

Let’s Get Deep Into Industrial Colorants

Colorants are employed in several industries to color garments, plastics, paints, prints, photographs and ceramics. Now colorants are also being employed in new applications and are termed functional as they aren’t just comprised in the product for visual reasons but for particular purposes, for instance in surgery.

Industrial colorants can be either pigments or dyes. Dyes are soluble colored natural elements that are generally employed to fabrics from a solution in water. They’re made to bond powerfully to the polymer molecules that make up the fibre textile.

Pigments are insoluble element employed in ceramics, plastics, printing inks and paints. They’re applied by employing a dispersion in an appropriate medium. A majority of pigments employed are also organic elements.

Throughout the procedure of a dyeing a fabric, the dye is dispersed amid the 2 phases, the aqueous phase and the solid fiber phase, and at the conclusion of the dyeing procedure the solution is exhausted and a majority of the dye is concerned with the textile. As soon as the dye molecules get into the fibre there’s instant interaction amid the 2 elements, which stops desorption of the dye molecules back into solution. This kind of interaction, whether chemical or physical, will rely on the groups on the dye molecules as well as in the fiber chains.

Categorization of industrial colors by procedures of application:

Classification by the method of application is important to the textile dyer applying the dye to produce the color required. To obtain the required shade the dyer usually has to make mixtures of dyes and must ensure that these are compatible.

The basic features that control dye transfer from solution to fibre are:

• the pH of the solution in the dye bath (for acid and basic dyes)

• an electrolyte (a solution of sodium sulfate or chloride)

• the temperature (within the range of ambient to 400 K)

• chemicals, known as dispersing agents, that produce a stable aqueous dispersion of dyes of very low solubility

pigments:

pigments are employed in the tinge of paints, ceramics, plastics and printing inks. They can be employed on a much wider range of materials than dyes because they’re not dependent on water solubility for their application.

The chromophores used in pigments are typically the same as those used in dyes but the pigments are large molecules and don’t have solubilising groups. They contain groups that form intermolecular bonds that assist to decrease solubilities. The larger the molecule, the more solid the pigment.

What’s Pearl Pigment & How It’s Used

Do you know something about the pearl pigment? Maybe you heard of pigment. A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. What is pearl pigment? It is a kind of inorganic pigment, have some special features: non-metallic, not including the heavy metal, chemical inertia, non-poisonous, safe for the surrounding and human being. You may see many different types of pearl pigments here.

The most common type is the silver white pearl pigment. It is mica powder coated by titanium oxide, and according to lights' many times reflection, it produced pearl luster. If the mica powder's particle size is bigger, the pearl luster will be better, but the coverage will be worse.

Silver white pearl pigment consists mica coated with TiO2. The different coating layer and the different particle size of mica will produce pearlescent pigments with different silver white effect. For TiO2, there are two kinds: one is Rutile, the other is Anatase. So, if asked for high weather resistant it is better to choose Rutile products. For Mica if the particle size is different, the pearlescent effect will be different as well. If the particle size is coarse it has better luster and higher transparency, even produce a shimmer effect. But for the smaller particle size, it has soft luster and strong coverage performance.

In pace with the growth of living condition, people demand to have more luster paint perfect in color for indoor decoration, and pearl luster pigment is the answer. Pearl luster pigment is excellent in dispersion, and good in physical and chemical property. As such, pearl luster pigment is suitable for mixture with any single-color paint to make pearl paint, which not only affect the color result, but also enhance the color expression of paint.

Aqueous pigment dispersions are widely used in different industry. In addition, pearl luster pigment also is suitable for most of both oil-base and water-base paint, especial for see-through materials which can promise you the desirable result. However, when pearl luster pigment makes into a mixture with non-transparent paints, the result of pearl luster may seriously affected. Another thing that should be circled out is never process the pearl luster pigment in grinding machine with high shearing stress to avoid destroy the structure and luster of the pigment.

The products have more than one hundred varieties, widely used in various industries, such as paint, plastic, ink, leather, printing, dyeing, rubber, paper making, master batch, etc, and give their products enthralling outlooks and gentlest luster.

Add Visual Attraction To Your Cuisines With Food Colorants

Just imagine your food as black and white! Or some dull colors like muddy Grey! Will you be tempted enough to eat them? Most of the people would not. Seeing is very significant for us human beings and that is a known fact since ages. Early civilizations introduced color into their food and that too very naturally. Ancient Egyptians made their food yellow with saffron. Wines were also colored in 400 B.C.E. using saffron only. Romans colored their white bread by mixing alum to the flour.

Today our food processing industry uses many types of industrial colorants, the main being- Food Dyes and Lake Food Colors. Not only food stuff ,but pharmaceutical products, cosmetics, inks, plastic food containers etc. are also colored with these artificial colors. So when you are having those colorful vitamin pills or using that lipstick, you are consuming these artificial food colors. It's not that only synthetic food colors are used in processed foods and other materials, there are many organic lake colors (organic lake pigments) too that are widely used for coloring food, thanks to the awareness about organic living! These organic lake pigments are obtained from natural sources. Some of the examples of such organic lake food colors include caramel, turmeric, beet and berry juice, paprika, saffron etc.

There is a wide range of synthetic colors too that are safe and commonly used in culinary preparations to make it more attractive and tempting for the palates. Synthetic foods are offered in highly purified form and are approved under the pure food and drug act, making it completely safe for the users. Synthetic Food Colors are commonly used in syrups, cakes, biscuits, candies, ice creams and fruit juices among others. Archaeological evidences show the use of synthetic food color to over 3000 years ago and their popularity has only increased with the passing times.

Synthetic food make the preparations more delectable and appetizing as taste is largely influenced by the smell and appearance of food stuffs. There are many synthetic colors including Allura Red Amaranth, Black, Green, Sunset Yellow, red etc and are used to give richness to even natural fruit drinks like orange juice.

Blended colors are made by mixing two or more colors for the desired color result. These water soluble coloring agents are combined in the desired fashion to get the right color. Blended are typically made to cater to the unique needs of the customers and are manufactured in compliance with the international quality standards. Blended are used in ice creams, fruit drinks, pastries and even pharmaceutical products. Some of the examples of industrial colors include pink, chocolate brown, lemon yellow, purple and pea green - to list just a few.

Different Types Of Pigments For Paint And Coating

In today’s world, there’s a big number of pigments accessible. Following the introduction of synthetic pigments, various categories of pigments has evolved that are suitable to particular kinds of industries. Let’s discuss about the kind of pigments briefly.

Inorganic pigments:

This type of pigments are developed via chemical manufacturing instead of grinding & washing minerals or clay taken directly from the earth. The preparation procedure is also very simple and comprise the steps of cleaning, drying, pulverizing and blending into a formulation. Few Examples of inorganic pigments: lead oxide, cobalt blue, chromium oxide, cadmium yellow, and nickel titanate. Almost all of the inorganic mineral pigments used today are manufactured, or synthetic. A synthetic version of a pigment may be chemically identical to the natural form, but it is produced artificially rather than naturally. It may also be an entirely new pigment created from minerals.

Organic pigments:

Organic Pigments are chemically synthesized, as they are not found in nature. They contain carbon and comes with relatively low levels of toxicity, not providing any major environmental concern. Raw materials can include coal tar and petroleum distillates that are transformed into insoluble precipitates. They are used as mass colorants and are popular in plastics, synthetic fibers and as surface coatings-paints and inks. In recent years the organic pigments are used for hi-tech applications that includes photo-reprographics, opto-electronic displays and optical data storage.

Key features & characteristics of Organic Pigments

• Good tinctorial strength

• Cost effectiveness

• Consistency and unique shades

• Completely non-toxic

• Organic pigments shows good color strength

• Very good stability to solvents, light, heat, and weathering

• Very bright, pure, rich colors

Metallic pigments:

Metallic Pigments give bright effects, due to this they are widely used and are a very popular category of pigments. Metallic pigments, can be of two types aluminum and zinc.

Because many of these new pigments for paints were less costly, and because there have been dramatic improvements on the range of available colors, many of them were made available before rigorous testing for bleeding was performed. For those painters for whom bleeding of one color into another, no matter how slight, is a problem, a simple, but not conclusive, bleed test can be performed.

The new, synthetic pigments for coatings are still derived from such natural substances as petroleum, but they have been chemically modified to create a new substance that is unnatural to the environment and, to many, has an unnatural appearance. Many of these colors, because of their industrial applications, are now part of our cities’ visual environment, our synthetic environment.

Milk paint Pigments – The Natural Way To Go

Following the industrial revolution decorative color pigments from atypical sources, like botanical substances, animal waste, mollusks and insects, where yielded and traded over long distance.

Pigments made from the female form of the "Cochineal", an insect inhabitant to Central & South America, are still employed nowadays in food, dye, plastics, body paint and fabric. These pigments were employed by Peruvians since prior to the eighth century and they were too employed by the Catholic Church for its cardinal vestments. Pigments based on clays and minerals often bore the name of the region or city where they were excavated. Burnt Sienna and Raw Sienna came from Sienna Italy; while Burnt Umber and Raw Umber are from Umbria.

Pigments powders can be blended with and employed to concrete, color stucco, resins, plaster, epoxies and wood putties, employed in milk paint as a binder or blended with other pigments for paint to transform the color or put in intense color.

Master painters of the regeneration era made their own materials and tools, including paints. Master painters took on learners to perform much of the job of preparing substances, making tools, and blending pigments. In exchange of their efforts, the learners learned the methods of painting from the masters.

Several premature Renaissance artists employed gold leaf as a backdrop to their gesso treated paint boards; a layer of clay followed and eventually the gold leaf was executed, employed only to improve a mystic halo effect over a Madonna, or a fire. Keep in mind that this procedure wasn’t just time taking, gold was very costly and hence employed very rare.

Today we’ve all of the same pigments for coatings dating back to the prehistoric Egypt and more but diverse synthetics and chemicals have been incorporated to the listing. The fashion, though, is towards the more natural milk paint kind items.

We now add in most of these methods in the same manner that they were employed in the earlier days but we’ve incorporated chemicals that have an effect on the greening of our earth in an unconstructive manner. Fortunately, things are changing and lesser chemicals are being employed nowadays and the ones that we do utilize are cautiously checked by government bodies.

Nowadays we notice a radical transformation in our surrounding and the way we view it. Natural pigments are employed more frequently as we came to know how to recognize the worth of safeguarding our natural supplies.

The utilization of milk paint, that employs organic pigments, looks to be the best way to go.

Use of Dispersing Agents For finest Product Performance

Dispersing agents are used in a variety of applications within the chemical manufacturing industry. Paint, adhesive coatings, mineral processing, and even paper making industries often outsource some of their work to chemical manufacturers well-versed in creating these dispersants. Also called plasticizers, they could either be active non-surface polymers or even surface active materials typically added to a suspension liquid agent.

Defining a Dispersant

A dispersant or plasticizer is basically an additive which can increase the fluidity of a material, preventing clumping or sediment settling. This kind of additive could be a gas but more often is likely an active non-surface polymer or even an active surface substance. The particle separation in a specific material is improved with this additive and can be used in a wide variety of chemical manufacturing instances.

 

Dispersing agents can be used in plastics, concrete, cement, gypsum wall board, clay materials, adhesives, paints, specialty coatings, paper products and even mineral processing. While some of the same dispersants can be used in a variety of these different applications, they can and do act a bit different in each case.

What are the potential advantages of using Aqueous pigment dispersions?

In physicochemical terms, Aqueous pigment dispersions can reduce interactions between pigment particles in a much more efficient than conventional dispersants. The most obvious is to reduce the viscosity of the formulation.

The ability to reduce interactions between pigment particles also confers certain benefits associated with the optimization of tinting pigments. We can subdivide the advantages of these dispersants in productivity gains (higher concentrations of pigment), color power (more efficient use of color) and coating quality.

Industries that Use Dispersant Technology

Many chemical manufacturing applications exist which may require the use of dispersants or plasticizers. Companies that manufacture adhesives and even latex products, particularly paints require dispersants. Painting and special coatings for a variety of products including automotive parts are additional industries. Concrete and cement production uses dispersant technology as well as chemical manufacturing applications that deal with pigments. Making paper, mining and processing minerals and even detergents use it too.

Whether you manufacture gypsum wall board, concrete or paint materials, having a company that can service all your dispersant needs is important, especially if you handle more than one type of product. Instead of working with multiple manufacturers, you should have one versatile company that can handle your need for unique dispersing agents.

You want to be able to get your dispersing agents from one source rather than multiple ones to save time and money.