CIvit ( Swlntonia florlbunda ) veneer,
dry (1J—12 percent moisture content)
boric acid and 1.9 percent
for 10, 25 and 40 minutes,
three-ply plywood.
1.5 mm thick, both green and
were soaked in 1 25 percent
borax solutions separately at 90° —100°C
These were conditioned and glued into
with a ureaformaldehyde adhesive fortified with
melamine, for producing boil-resistant glue-bond. Plywood shear test
samples were prepared and tested in both dry and wet (boiled in water
for six hoyrs and tested while wet) states.
Dry shear tests show that green veneers treated with both boric
acid and borax, and dry veneers treated with borax had the higher
bond strength, while the longest treating time (40 minutes) had the
lowest bond strength, all the differences being significant at the 5%
level. The wet test shows significant differences at the 5% level
between the preservatives, borax treatment producing better bond
strength However, all the treatment combinations resulted in adequate
bond strength for the type of plywood produced.