Paint brushes can be classified as either synthetic bristle or natural bristle brushes. Synthetic bristle brushes are typically made from nylon, polyester, or blends of these materials. Natural bristle brushes are produced with animal hair such as natural hog hair and ox hair.
When applying water based paints, only use brushes constructed with synthetic bristles (filaments). Synthetic bristles are much more water resistant than natural bristles making them the only choice for latex and acrylic paints. Because synthetics do not easily absorb water they are able to maintain their shape and perform well.
Nylon filaments are very durable and resist wear on rough surfaces. Nylon is also a relatively soft bristle. It does not offer the stiffness and flex to that of polyester. Even though nylon has a superior durability, its lack of stiffness does not make nylon brushes the best choice for rough surfaces. Nylon filaments also tend to soften and lose their shape with prolonged use and hot and humid conditions. Nylon is very easy to clean. Paint brushes constructed with nylon filaments are best suited for use with water base paints on interior smooth and semi-smooth surfaces.
Polyester filaments perform especially well to resist water absorption. This enables polyester paint brushes to maintain their stiffness and maximize flex during use. Because 100% polyester brushes do not have good resistance to abrasion, they do not stand up to heavy use on rough surfaces. Polyester also tends to leave brush marks. These filaments are very difficult to clean, but may be used with all paints. Polyester brushes may be a good choice for exterior painting applications on smooth, semi-smooth, and semi-rough surfaces.
Nylon/Polyester blends bring together the positive characteristics of nylon and polyester. Paint brushes made with these filaments offer the softness and durability of nylon along with polyester’s stiffness and ability to maintain its shape. They work well for interior and exterior painting applications, with all types of paint. The nylon/polyester blend can be used for rough and semi-rough surfaces because of the durability of nylon combined with the stiffness of polyester. It also works well for smooth surfaces because of the softness and tipped ends of nylon. Some effort is required for cleaning, because of the polyester content.
Engineered Nylon is a term that some brush manufacturers use to describe advanced nylon filaments. Engineered nylon is a type of filament that retains all the positive characteristics of nylon with added stiffness for better control.
When working with oil base paints or alkyd paints, the natural bristle brushes are a good choice. Although they are not nearly as durable as the synthetics, they do give you the ability to achieve a smooth, level finish. The types of bristles commonly used are hog hairs and ox hairs. The hog hair bristles are self flagging which gives them the ability to hold more paint and spread it evenly. Certain characteristics of these animal hairs cannot be reproduced by synthetics, making the natural bristle brushes the best for oil base paints.
Never use a natural bristle brush with water base coatings! The natural fibers will absorb water making them sticky and causing them to lose their shape.
Black China Bristle is a natural bristle made from hog hairs. Black china bristle paint brushes are fine to use for the application of all oil, alcohol, and solvent base paints, including alkyd enamels, oil base primers, and oil base stains. The bristles are slightly coarser than the ox hair or the white china bristle making them preferable for semi rough and rough surfaces.
White China Bristle is also a natural bristle made from hog hairs. White china bristle paint brushes have softer bristles than that of the black china bristle brushes. They work well with all oil base and solvent base paints. They perform especially well with fine oil base paints such as alkyd enamels, clear wood finishes, and oil base stains. A white china bristle brush is a good choice where a smooth finish is desired.
Ox Hair is a natural bristle obtained from the ears of oxen. They are the softest bristles amongst all the natural bristles, which are commonly used for paint brushes. Unlike hog hair, they do not have flagged ends, but rather come to a fine point. Ox hair bristles are always blended with hog hair in order to capture the positive attributes of both types of bristles. China bristle, having naturally flagged ends, has the ability to hold more paint than ox hair. The hog hair also offers added durability to the blend.
Brushes blended with ox hair bristles are the best to use on smooth surfaces where a very fine finish is required. Their ability to bring a superior finish, make them a great choice for fine alkyd enamels, polyurethanes, varnishes, and brushing lacquers. They are more expensive than the china bristle paint brushes.
Nylon – Works best for interior and limited exterior painting on smooth and semi-smooth surfaces. Use nylon only with water base paints. Try not to leave nylon submerged in paint for a prolonged period of time because it will lose its shape.
Polyester – Works best for exterior and limited interior painting on semi-smooth, semi-rough, and rough surfaces where a very smooth finish is not necessary. Use polyester with all types of paint. Polyester can be very difficult to clean.
Nylon/Polyester Blends – Performs well for interior and exterior painting on all types of surfaces with all types of paints.
Black China Bristle – Fine for interior and exterior painting for all types of oil base and solvent base paints on all types of surfaces. It is the best of the natural bristle brushes for heavy bodied, oil base paints.
White China Bristle – Works well for interior and exterior painting, with oil base and solvent base paints, where a finer finish is desired. White china bristle has more delicate flagged tips than that of the black bristle, which makes it a better choice for finer finishes on smooth and semi-smooth surfaces.
Ox Hair Blends – Best for interior painting where an ultra fine finish is desired. They are the best among the natural bristle brushes for finer oil base and solvent base paints on smooth surfaces.