How Are Offers Manufactured With Color

The process of manufacturing paint has been refined but not drastically changed in centuries.

At the chemical level, the colorants used in any manufacturing process are the same. Housepaint, plastics, colored leather, textiles, ceramics, paper, cosmetics and all the varieties of fine art paints use the same pigments, the only difference being how the pigments are designed in terms of lightfastness, particle size, purity, hue, chroma and, of course, cost. Today, all colorants are synthetic compounds, and the variety available depends largely on the demands of the largest market share using the colorants, which are manufacturing companies that specialize in foods, house paints, inks, automobiles and plastics.

How the individual paints are made, however, varies according to medium and is dependent on the binding agent used. This process will be better understood after a brief review of the backbone structure of paint, the function of the different ingredients involved and a breakdown of what pigment is and how it is categorized.

Backbone Composition of Paint

In the simplest terms, paint is nothing more than microscopic particles of pigment suspended in a vehicle, or medium. The basic recipe for making paint varies by manufacturer, but usually it includes pigment mixed with a brightener, a binder, plasticizer, humectant, filler, manufacturing additives and water. Paint gets its color from pigment; the rest of the ingredients comprise the vehicle, which is what makes the pigment usable as a paint.

The type of binder used determines the medium of the paint and usually gives the paint its name; for instance, oil paint uses a linseed oil binder, acrylics use an acrylic polymer binder and egg tempera uses egg whites or yolks. Watercolor paint is an exception--gum arabic is typically the binder, or sometimes other gums or animal glues, and water is the solvent.

The Function of Ingredients in Paint

The binder is the first, most crucial ingredient of the vehicle. It is a transparent liquid that transforms the pigment into a viscous fluid that can be painted with, it holds the pigment on the surface of the paper, canvas or other support, making the paint appear brighter, and it adheres the pigment to the support.

Some binders, such as gum arabic, tend to crack, darken or flake when dry. A plasticizer is added to paint to counteract these problems and also to retard drying in the tube. Glycerin is the most commonly used plasticizer for water-based paints, but other substances can be used; methyl cellulose, for instance, is used as both a binder and plasticizer in pastels and chalks.

A humectant is often added to help retain water in the paint, thus inhibiting drying and softening the paint. Carbohydrates like sugar syrup or honey have been used since the 19th century for this purpose. Humectants also make water-based paints easier to redissolve after they dry out on the palette.

Fillers are added to paint to thicken paint, make the consistency more similar from color to color, tone down especially vibrant hues of some pigments and reduce the cost of the paint. They are also necessary to keep paints from getting too glossy and lifting from the support too easily. Dextrin is one commonly used filler which can also be used as a binder; carrageenan or funori are also used.

Other additives come into the paint either in the packaging stage or during milling. These commonly include a wetting agent that helps speed up the mixing process when the paint is manufactured, additives that increase the shelf life by keeping the pigments mixed evenly with the vehicle and preservatives or fungicide to keep mold from growing.

Water is also added, especially in the initial grinding and mixing process of paint manufacturing. Most of the water evaporates away before it is packaged, but some remains, decreasing in direct proportion to the age of the paint.

What Is Pigment?

Pigments are chemical compounds with the attributes of color. Unlike dyes, pigments do not dissolve in water. They are either natural or synthetic, organic or inorganic. These four categories classify pigments as falling into one of four classifications: natural inorganic, synthetic inorganic, natural organic and synthetic organic. Natural inorganic pigments exist in nature as minerals such as clays, rust, stones and silica. Some examples include yellow ochre, burnt sienna, raw umber and lapis lazuli (natural ultramarine blue).

Natural organic pigments are made from roots, plants and animals. Because they are not very lightfast, natural organic pigments are not used in commercial paints, but some examples of these pigments are madder reds made from roots, carmine red from insects and indian yellow made from cow urine.

Synthetic pigments are not found in nature, but are manufactured to mimic and improve upon those found in nature. Iron blue, cobalt green, cobalt blue and zinc oxide were made before 1800 and are still used today. Nearly every paint manufactured today uses synthetic pigments, both because they are an improvement upon the natural compounds, which tend to deteriorate and fade with time, and also because of environmental concerns and scarcity regarding the use of natural pigments.

Pigment Manufacturing

Most pigment is not used for fine arts, but for a vast number of other industries including automobile paints, housepaints, printing inks, tattoo inks, pharmaceuticals, wood stains, dental ceramics, foodstuffs, colored leather and more. Pigments are manufactured by chemical companies across the world, such as BASF, Hays Colours, Sun Chemical Corp., Bayer, DuPont and so on. These companies create, refine and package the pigments in different forms dictated by the market needs and the properties of the pigment. Some pigments must be packaged as moist pastes, or else they would clump and become unusable. Others can be manufactured as powders, pressed into cakes or as fine grains.

How Paint Is Manufactured

Our machines and processing lines have increased the amount of paint that can be made at once, but other than that the basic mechanics of making paint have not changed much in over a hundred years. First, the paint manufacturer assembles the necessary raw ingredients, such as pigment, and grinds them to final specification. After that, the ingredients for the vehicle and the pigments are mixed into a paste which is then milled. Milling is the mixing of pigment and vehicle, and it is usually done on a machine with three large steel rollers that crushes, smears and folds the paste until it has reached the desired consistency. This can take several hours or several days, and when the milling is complete, the finished paint must age. Aging is necessary to ensure that the pigment completely immersed in the vehicle. Improperly aged paint will squirt out of the tube when opened, burst the packaging or harden in the tube. The last step is packaging. Depending on the paint, it is either poured into pans or tubes; if tubes, the cap is left on and the paint fills from the bottom. When it is full, the tube is crimped closed, labels are added, and the paint is ready for marketing.

Prairie homes

Thursday, May 30, 2013