Ad
related to: white paper bleaching methods for painting wood- Biggest Sale Ever
Team up, price down
Highly rated, low price
- Men's Clothing
Limited time offer
Hot selling items
- Clearance Sale
Enjoy Wholesale Prices
Find Everything You Need
- Special Sale
Hot selling items
Limited time offer
- Biggest Sale Ever
Search results
Results from the WOW.Com Content Network
Bleaching of wood pulp is the chemical processing of wood pulp to lighten its color and whiten the pulp. The primary product of wood pulp is paper , for which whiteness (similar to, but distinct from brightness) is an important characteristic. [ 1 ]
In the production of white paper, the wood pulp is bleached to remove any color from the trace amounts of lignin that was not extracted in the chemical pulping process. There are three predominant methods of bleaching: Elemental chlorine bleaching uses chlorine and hypochlorite.
Elemental chlorine free (ECF) is a technique that uses chlorine dioxide for the bleaching of wood pulp.It does not use elemental chlorine gas during the bleaching process and prevents the formation of dioxins and dioxin-like compounds, carcinogens.
Often, the wood's color is changed by staining, bleaching, or any of a number of other techniques. Once the wood surface is prepared and stained, the finish is applied. It usually consists of several coats of wax, shellac, drying oil, lacquer, varnish, or paint, and each coat is typically followed by sanding.
Mechanical pulping is the process in which wood is separated or defibrated mechanically into pulp for the paper industry. The mechanical pulping processes use wood in the form of logs or chips that are mechanically processes, by grinding stones (from logs) or in refiners (from chips), to separate the fibers.
Dissolving pulp is mainly produced chemically from pulpwood in a process that has a low yield (30 - 35% of the wood). This makes up of about 85 - 88% of the production. [ 2 ] Dissolving pulp is made from the sulfite process or the kraft process with an acid pre hydrolysis step to remove hemicelluloses.
The use of wood to make pulp for paper began with the development of mechanical pulping in the 1840s by Charles Fenerty in Nova Scotia [1] and by F. G. Keller [2] in Germany. Chemical processes quickly followed, first with Julius Roth 's use of sulfurous acid to treat wood in 1857, followed by Benjamin Chew Tilghman 's US patent on the use of ...
It is used as such in some industrial dyeing processes to eliminate excess dye, residual oxide, and unintended pigments and for bleaching wood pulp. Reaction of sodium dithionite with formaldehyde produces Rongalite. Na 2 S 2 O 4 + 2 CH 2 O + H 2 O → NaHOCH 2 SO 3 + NaHOCH 2 SO 2. Thus is used in bleaching wood pulp, cotton, wool, leather and ...
Ad
related to: white paper bleaching methods for painting wood