CONSUMER/EROSKI the substance more advisable to lighten wood is oxygenated water. The use of gloves, mask and protective goggles, is compulsory as is a high risk of Burns and intoxication. Bleach, oxalic acid and Sodium Hydrosulphite are other very suitable products to whiten wood. Wood is warm, durable and decorative. However, all of our furniture suffer with the Sun. Sun rays or the passage of time obscure them completely or partially. It happens also that the ctos are much noticed because the blackening of wood is logged in certain areas and not in a uniform manner. Posts to retrieve a piece of furniture, the most advisable substance for clear wood is oxygenated water, since Consumer/Eroski, remember just damaged Woody fibers. This hydrogen peroxide can be used in any type of wood without the need to rinse after application, since its components evaporate to dry out. For best results, should be peroxide 130 volumes. However, the action will be more aggressive if you use oxygenated water of 100 volumes with pure ammonia mixture at a ratio of 95 parts by 5, respectively. Precautions when using hydrogen peroxide once sanded wood surface, extends over the same chemical compound with a white cloth. This should not be of cotton, since this material degrades easily by the action of the oxygenated water. After a few minutes, the treated area with a cotton cloth is rubbed with energy. If the result is not expected, you can repeat the process passes a few hours. Volume is the measure that is used to identify the concentration of hydrogen peroxide solutions. In this case, 1 volume is equivalent to a solution of 0,3% of hydrogen peroxide (H2O2) and 99.97% of water (H2O). If you consider that the hydrogen peroxide that is used with disinfectant and medicinal purposes has 10 volumes, means the reason why, to use this product to one ten times higher concentration, is obligatory the use of gloves, mask and protective eyewear, since the risk of Burns and poisoning is high. Other whitening products bleach, oxalic acid and Sodium Hydrosulphite are other products listed to bleach wood. Bleach must have a concentration of 12%. For its application on wood should be used diluted to avoid the yellowish tone that can leave on the furniture. However, the greater the dilution, the smaller its bleaching power. Oxalic acid should be diluted in water or alcohol before use. To increase his power bleaching, must apply it hot. Given its toxicity, post-treatment should wash wood. Sodium Hydrosulphite, is a white crystalline powder that gives off a strong scent to sulphur. This compound is soluble in water and is used in aqueous solution at 10%. In this case you also need to wash the surface of wood after application. Source of the news: how to recover a Cabinet blackened by the Sun and time.