Wood from older trees may have older color (darker) when compared with the wood from younger trees of the same type. Dry wood in different colors when compared with the color of wet wood. Wood that has been stored in the open color can be darker or lighter than fresh wood, this depends on the circumstances (weather, wind, light, and so on). In general, the color of a particular type of wood is not a pure color, but color is a mixture of several kinds of colors, so that in appearance it is difficult to be expressed precisely in words.

As the Giver of Extractive Substances Natural Color Wood

The color of wood caused by a material that can be extracted, which are called extractive. Extractive is a chemical in a timber that can be dissolved in a neutral solvent such as water, ether, alcohol, benzene and acetone. The content of extractive in wood varies from less than 1% to more than 10% and can reach 20% for tropical timber. Each type of tree contains one or several kinds of extractive substances and only a few species of trees that contain all extractive substances.

Flavonoids, stilbena, tannins and anthocyanins is a class of dye wood extractive. Flavonoids are compounds that cause the wooden porch of red, yellow, brown or blue. Polyphenols and tannins in the wood broad leaves have a great contribution to the color of wood, especially wooden color terraces and in the past few broad leaves of wood used as dyes. Phenolic contained in a wooden porch, and a little skin in the xylem has a function as a fungicide and in addition it also serves to enhance the staining of wood.

Extractive substances is influenced by growth conditions. For example, differences in walnut color from different geographical locations, related to soil properties. Extractive chemical differences allow to distinguish between types of wood or made ​​of wood staining colorless terrace with the application of chemical substances. Some of the wood such as black locust, honey locust and some tropical wood species have fluorescent for extractive substances.

Color As One Of Wood Identification Tool

To know the properties of wood can be used either coarse (macroscopic properties) as well as structural properties (microscopic properties). Included in this is the rough nature of color, luster, smell, taste, texture, fiber and figures. While the nature of the observed structure consisting of pores, parenchyma, the radius, inter cellular channels, lymph channels, and skin inserted. Physical properties can be determined directly by the senses without having to use the tools on the contrary nature of the structure usually use aids in the form of a magnifying glass with magnification of 10 times.

Colors characterize the various types of wood, but it is a trait that is difficult to describe with words. In one species there may be differences and changes due to exposure or as a treatment. Usually the color is expressed visually, but can also be measured technically.

If we want to use color for identification, then the color used is wood paneling. Wood color sapwood usually less real or less typical, so less is diagnostic for the introduction of wood. The color of wood into a value that is important for identification. For example, ebony wood has the typical black color. To determine the exact color can be used Spectrophotometer instrument. This tool can reflect light from a number of different wood surfaces using ultraviolet light.

Further stated also that often there is a striking range of colors, followed by a variety of other colors, so it is difficult to split up individually. Due to the nature of color is easily changeable, then the use of wood in the identification of a secondary color, so it should be used with caution.

To be continued....

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