Application of Dyes and Pigments
In rubber industry, for bringing different properties like durability, resistance against heat and light reinforcement capacity etc., in the rubber products, different types of pigments are applied. Some of the pigments that are applied/used in the rubber industry are:
Carbon Black is a type of pigment which is derived from the refinery process of petroleum. In tyre manufacturing process, it is used for producing high resistance, abrasion and longevity and grip. These qualities are required for any tyre to become successful. Carbon black has wide variety of applications in different kind of rubber products. This range of rubber products starts from aerospace to ordinary household products.
Organic pigment powders are also useful in the coloring process and to develop other specific properties in the rubber made products.
In rubber applications, Titanium Dioxide pigments are also used. These pigments are used during the application process of rubber because these pigments have some good qualities. These good qualities are: high refractive index, consistency in the size of the particles, dispersibility, and high ultra violet ray resistance.
Florescent is a kind of bright pigment and its powder form i.e. called as Powder Color is used in the rubber industry. This kind of pigments may be both organic and inorganic nature. The proper color selection depends primarily upon some requirements of the manufacturers. These requirements are light stability, heat stability, resistance to bleed, resistance to migration and required shade.
The pigments which are used in the rubber industry, are generally bifunctional organic silicon compounds. These compounds have two reactive groups. For high quality rubber compounds, these pigments are used. When this kind of pigments are used in the rubber industry combined with sinaloan group-carrying pigments, then the effectiveness will become more effective.
Another type of pigments that is used in the rubber industry is Molybdenum Pigment. These pigments are light, heat stable and having bright color range from bright red-orange to red-yellow. Apart of rubber products, these pigments are also used in ceramics, plastic, paints and inks. The other kind of pigments that is known as Ultramarine pigments, are also used for rubber products. These pigments have high heat resistance, light and weather resistance.
Although Cadmium pigments have no major application in rubber industry, but, for many minor purposes, these pigments are used in the rubber industry.
Since its inception, rubber industry has been using Zinc Oxide. The great importance of zinc oxide to rubber industry is due to so many optical, physical and chemical properties of zinc oxide. Tyres, for heavy pneumatic duty and durability, require high loading of zinc oxide for high heat conductivity as well as reinforcement since heat building is critical at their higher operating speeds.
In the curring process for most kinds of synthetic rubber sand natural rubber, the chemical reactivity of zinc oxide is required for activating the organic accelerator.
Some special properties of Zinc Oxide that make it popular for the rubber industry are:
Zinc oxide has a very high stability (resistance) of heat. So, when it is used for tyre manufacturing, then tyres become more stable and durable even at the high temperature.
It gives enough stability in the gelation of foam, when latex foam rubber product is manufactured.
Out of all other white pigments, Zinc oxide has the maximum capability to absorb the Ultra Violet rays. So, when it is used with the rubber tyres, then the rubber tyres get extra stability to the destructive sunlight. Zinc oxide is specially used with the white colored tyre and tinted rubber because these rubbers required extra stability.
As zinc oxide has high brightness, high refractive index and proper particle size, so, when this pigment is mixed with rubber products, then the products will become more whitish. This pigment is specially used in rubber made medical surgery equipments, rubber sheeting and side walls of the tyre.
Natural rubber gets reinforcement from these pigments.
Rubber - Metal Bonding
Zinc oxide reacts with copper oxide for the bonding of rubber to brass.