Wood is considered to be one of the most important renewable natural resources available to man. The strength properties of solid wood and the natural durability of certain species of timber offer a material which could be used in a wide range of applications such as a building material, tools and utensils, furniture, as well as providing a source of extractive for industrials, domestics and pharmaceutical purposes. In addition wood is the basic raw material in the paper making and textile industry and is also used in the manufacture of wood composites and panel products (Youngs, 1989). In fact timber is considered to be the man’s first structural material and today timber is used for a greater number of products than any other material (Brazier, 1987).
Human induced climate change is one of the most pressing and complex issues facing society in the 21st century. Increased use of forests and wood products, while not replacing the need to reduce greenhouse gas emissions at source, does make an important contribution towards tackling the problem of climate change (Hannah et al, 2004). Trees sequester carbon during their life, pulling carbon dioxide (CO2) from the atmosphere and storing it in their mass. For every kilogram of wood grown, 1.5 kg of CO2 is removed from the atmosphere (ASCE, 2010). Storing CO2 in wood could therefore be considered as an effective means of mitigating climate change, though wood also releases CO2 when they used as fuels (Philippe, 2013). Wood processing operations generate enormous amount of wood residues and effective use of them for alternative uses is therefore have a significant impact on lessening the effect of climate change (Bernad, 2014).
Wood residues like saw dust, trimmings and edgings are typically viewed as a burdensome disposal problem (FAO, 1990). However the material has a potential to become a usable resource (Bernad, 2014). Wood particles such as saw dust, timber off-cuts, wooden crates, wooden packaging, wooden pallets, wood shavings and similar materials are considered as wastes (NSWEPA, 1997). The New South Wales Department of Environment and Climate Change defined wood wastes as waste referring to the end-of-life products, failed products, off-cuts, shavings and sawdust from all timber products (NSWWB, 2000). Four types of wood wastes are usually generated within the furniture manufacturing companies as the result of the technological process: solid wood offcuts, engineered wood offcuts, sawdust and shavings (Daian & Ozasrka, 2009).
Off-cut wood is currently one of the wastes dumped by sawmills and as they failed to fully utilize the wood supply. Waste sawn timber material of furniture factory and short length of sawn timber are considered to be a key issue in timber industry, though a few of them is already being used in fuel kiln dried boiler. Another means of utilization of the wastes is applying a jointing system through the finger joint technique. This technology ensures maximum utilization of the timber wastes minimizing the pressure on forest resources (Muthumala et al, 2019). Finger joints are explained as interlocking end joint formed by machining a number of similar tapered symmetrical fingers in the ends of timber members using finger joint cutters and then connected together by bonding material (BS EN, 15497). Finger joint is a sustainable, eco-friendly and economically valuable concept for furniture industry. It ensures the sustainable utilization of small wood cut pieces which removed as waste (Sandika, 2017).
Wood in suitable environmental conditions can be attacked by bacteria, fungi, algae, insects, marine borers and some other biological pests. The presence of wood-damaging agents has to be limited by using suitable techniques in order to minimize the contact of wood with rain and other sources of water, which could enhance the creation of water condensate. Chemical protection of wood is performed with preservatives, such as fungicides, insecticides, fire retardants and UV protective finishes that are applied on the wood’s surface. The chemical protection of wood is performed with chemical protective agents called “wood preservatives”. Fungicides which used for wood protection are classified into two groups as organic and inorganic, according to their chemical structure (Reinprecht, 2016).
Some treatment processes like drying, impregnation and surface treatments are applied to enhance the durability of wooden materials and the most commonly applied protection method for wooden materials is to treat them with an appropriate chemicals (Şen and Hafızoğlu, 2001). Boron compounds are the impregnation material that effectively against both insecticide and fungicide properties against insects and fungi destroying wooden materials. Boron compounds can be used for controlling wood attacks encountered due to termites and insects. Boron compounds are responsible for lower levels of environmental damage and no more toxic than common salt to humans. Boron compounds are accepted as one of the safest chemicals utilized as a preservative impregnation substance without heavy metals. (Lloyd, 1998; Kartal and Green, 2002; Yaşar and Atar, 2017, Muhammed and Hakan, 2019).
Boron (B3+) in the form of boric acid (H3BO3), sodium tetraborate (borax, Na2B4O7.10H2O) and sodium octaborate is normally used in aqueous solutions (Lin & Furuno, 2001). Borax and boric acid mixture is mixed with water for preserving the softwood as an indoor preservatives. Pine (Pinus caribaea), a major softwood species grown in Sri Lanka is used in furniture and other light construction works. Pine is an important source of raw material for sawmills, veneer plants, and paper mills (Gomes et al, 2004). Softwood timber species are subjected to easily deteriorate easily by the actions of wood destroying agents. Thus preservation is needed to enhance the durability of such wood. Main objective of this paper is to discuss the assessment of the impact on Borax-boric acid treatment for treated and untreated finger-jointed Pine wood under impregnation method.