The term "branding" means the marking of timber with identification symbols relating to the type or quality (grade) of the timber. After the timber has been felled it is normal to rough saw the green timber before it is dried. The green timber has a high moisture content (e.g. greater than 100% for softwoods and up to 150% for hardwoods) and must be dried before use, usually outdoors or in a kiln. Green timber is particularly difficult to brand on account of the high water content. Moreover hardwood is generally wetted during sawing as the saw blade often has to be cooled with a water spray.
Existing methods of branding freshly-sawn timber involve the use of various types of ink which provide neither distinctly legible grades of mark nor marks which can be maintained on the timber for a sufficient length of time, particularly in view of the rigorous conditions under which sawn timber is transported, stored and worked.
In particular, the branding must show satisfactory water resistance for storage outdoors. As timber is quickly passed out of the saw mill the brand must also be capable of drying within a short time. Typically less than 5 to 10 minutes. The branding fluid must also be economical and compatible with existing equipment.
It is an object of the present invention to mitigate these disadvantages associated with known methods of branding timber.