What is pigments?

• Types of coloring materials (dyes and pigments)
• Types and properties of pigments
• History of pigments
• pigments notation
• pigments uses
• Our organic pigments

Types of coloring materials (dyes and pigments)

There are many things around us that have beautiful colors. In addition to naturally occurring plants and animals, man-made objects such as brightly colored cloth, paper, vessels, and buildings add beauty to our lives. Coloring materials are used to color these artificial objects.

Coloring materials literally refer to ``raw materials for color'' and can be broadly divided into ``dyes'' and `` pigments.'' Both are colored powders, but dyes dissolve in water or oil and have the property of penetrating between the fibers of cloth, paper, etc. to dye them. On the other hand, pigments have a major difference in properties: they do not dissolve in water or oil, and can be colored by adding a binder (fixing agent) to the surface.

Pigment

The pigment settles on the surface of the paper and colors it.

dye

The dye soaks into the paper and colors it.

Types and properties of pigments

pigments are divided into two main categories: inorganic pigments and organic pigments. Inorganic pigments is pigments made from natural ores and oxides obtained by chemical reactions of metals, while organic pigments is pigments synthesized from petroleum and other materials. Inorganic pigments is further divided into two categories: natural minerals pigments and synthetic inorganic pigments.

Natural minerals pigments are literally pigments obtained from naturally occurring minerals and soil. Typical examples include ochre, peacock stone, and turquoise, which are still used today as rock paints in Japanese painting.

On the other hand, synthetic inorganic pigments are made from oxides and bonds obtained by chemical reactions of metals such as iron, copper, and lead. Typical examples include cobalt blue, lead yellow, and titanium white, which were discovered, manufactured, and used mainly between the 18th and early 20th centuries. Various other "special pigments" materials have also been developed, including fluorescent pigments materials that glow brightly in the dark, like neon signs.

History of pigments

We humans have been using pigments in various forms since prehistoric times. pigments murals of horses, sheep, and wild cows have been discovered in caves in the Lascaux and Altamira regions of France, near the border with Spain. The latest research has revealed that these murals were painted at least 15,000 years ago.

Most of the animal murals are painted in brown or black. This is due to the use of natural mineral pigments such as red clay and black clay, which were readily available and available, and it is thought that these clays were mixed with animal fat and painted on the walls of the cave. Since then, humans have continued to discover new natural mineral pigments (colored rocks and soil) and use them as coloring materials.

Natural mineral pigments are naturally formed on Earth over hundreds of millions of years. Therefore, it is resistant to discoloration even in open environments, and has excellent light and heat resistance. However, on the other hand, the particles are hard and coarse, and the coloring power is limited, so it has the disadvantage that sufficient coloring cannot be obtained unless it is applied over and over again.

Also, the most inconvenient thing is that since it is a natural product, the amount that can be harvested is limited. Some pigments, such as ultramarine (blue) made from a gemstone called lapis lazuli, were so valuable that they rivaled gold, and painters in the Middle Ages had to serve the royal court to receive pigments. Without it, it is said that painting would not have come true.

Against this background, producing pigments artificially has been one of humanity's long-held dreams. It is believed that Egyptians were making a synthetic pigments called ``lead white'' by soaking lead in vinegar as early as BC, but it was not until the 18th century that it became possible to produce it industrially in a stable manner. It was only after that. The first blue synthetic pigments that appeared was ``pigeon blue'', which was obtained by chemically reacting iron, and was successfully developed in Berlin, Germany in 1704. Since then, synthetic pigments that are inexpensive and can be supplied in large quantities have been developed one after another, and have become widely popular.

In the 19th century, organic pigments made by combining dyes and metals appeared. Organic pigments have many advantages over inorganic pigments, such as vivid colors, strong tinting power, and a wide variety of colors. In addition, in recent years it has been discovered that some inorganic pigments are toxic, so organic pigments that are harmless to the human body are becoming increasingly important.

pigments notation

Color Index Generic Name is a method used internationally to identify individual pigments. The color index name is a notation method for pigments registered in "CI (Colour Index International)" (a database jointly maintained by the British Institute of Dyeing and Dyeing and the American Textile Chemistry and Dyeing Technology Association).

C.I contains color index names based on utility and color for more than 6,000 dyes and colorants (pigments and dyes) and related compounds. In addition, each of them is given a "Colour Index Constitution Number", and their product name, chemical properties, manufacturing method, etc. are also listed.

On the other hand, pigments can also be identified by their "CAS number." CAS is an abbreviation for "Chemical Abstracts Service" and is a compound number used in the "Chemical Abstracts" magazine published by the American Chemical Society. A CAS number is a number of up to 10 digits that can be used to identify chemicals, including pigments.

pigments uses

pigments are used for a variety of purposes, not only in printing inks, paints, and plastics, but also in cosmetics, textiles, and food. The intended use varies greatly depending on the properties of pigments. For example, inorganic pigments, which have excellent weather resistance (resistance to light, wind, rain, and temperature changes) and are relatively inexpensive, are often used in paints for products that have large painted areas and are left outdoors for long periods of time, such as building materials and containers. . On the other hand, about 60% of organic pigments with excellent coloring power and vivid colors are used in printing inks, and about 20% are used as colorants for plastic products.

In addition, some pigments are used not only for coloring, but also for special purposes. For example, ``extender pigments'' (white and colorless pigments used as fillers) are used in cosmetics such as face powder because they are shiny and highly adhesive. Carbon black, which is a black pigments, significantly improves its strength when kneaded into rubber, so it is used in tire products such as automobiles, and due to its conductive properties, it is also used in electronic parts and magnetic tape materials. Masu.

Automotive

food packaging

Art supplies such as crayons

Our organic pigments

TOYOCOLOR 's organic pigments are used in a variety of applications that require color, including printing inks, paints, and plastic coloring, as well as color filter for LCD displays, toner for color copiers, and inkjet inks. In addition to hues and dispersibility suitable for a wide variety of uses, we support colorful lifestyles with a wide variety of products that have added features such as weather resistance, heat resistance, and safety depending on the manufacturing process and application of the product. doing.