Block board is made up of a core of softwood strips. These strips may be up to about 25mm wide. The strips are placed edge to edge and sandwiched between veneers of hardwood. The sandwich is then glued under high pressure.
Cigna Black Blockboards are made of 100% Imported New Zealand Pine. They are fabricated from extra thick core veneers and bonded with the best quality Resin, pertaining to the desired grade, under high temperature and pressure. Utmost care is taken to ensure uniformity so as to eliminate gaps and insure "0" Gap block-coards.
|S.No.||Test||BWP ISI 1659 GRADE Requirement||Cigna Black Results|
|1||Dimensional change caused by Humidity a) Max. change in length b) Max. change in thickness c)Max. change in local planeness||± 1 mm ± 1 mm Less than 1/150||0.50mm 0.70 mm 0.5 /150|
|2||Modulus of Rupture||Minimum 40.00 Newton/mm²)||1200Newton 1440 Newton|
|3||Modulus of Elasticity||Minimum 4000.00 Newton/mm²||1100 Newton 1200 Newton|