WINDBOND BR 101L is condensation copolymerization resin product comprising of melamine, urea, and formaldehyde. It has higher water and weather resistance and therefore it is suitable in the manufacture of BWR grade boards and panel for exterior use in the relatively high moisture content area.
Comparatively higher raw material cost compensate with superior properties of boards and panel.
Melamine content in WINDBOND BR 101L resin may vary between 20-30%.
PHYSICAL PROPERTIES AND SPECIFICATIONS FOR RESIN POWDER
|APPEARANCE||WHITE FREE FLOWING POWDER|
|VISCOSITY (1:1) AT 30°C||22-35 BY B4 CUP|
|pH OF 50% SOLUTION AT 30°C||8.0-9.5|
|POT LIFE AT 30°C||3-5 HOURS|
|SOLUBILITY||EASILY SOLUBLE IN WATER|
|FREE FORMALDEHYDE||MAX. 1%|
|VOLATILE MATTER (105°C/1 hr.)||MAX. 3%|
|POWDER||100 PARTS BY WEIGHT|
|WATER||100-110PARTS BY WEIGHT|
|WHEAT FLOUR||8 -12% OF POWDER BY WEIGHT|
|HARDENER||AMMONIUM CHLORIDE WITH AMMONIA SOLUTION|
Ammonium Chloride, 0.2 to 1.0% of Powder by weight following ammonia solution for neutralization of pH may be used depending on weather condition.
GLUE MAKING PROCEDURE
Take 50% of the total water in glue mixer. Add resin powder and required quantity of wheat flour. Mix well for 15-20 minutes until all powder dissolved and lump free paste is prepared. Then add rest of water and mix well for 10 minutes. Temperature may be maintained 20-35°C.
Check viscosity, if needed some water may be added to maintain the required viscosity 25-35 seconds in B6 cup.
Mix the hardener immediately before use.
REACTIVITY OF GLUE
The selection of reactivity would normally depend upon the local conditions. The reactivity of the glue can be adjusted over a wide range by varying the composition and quantity of hardener.
POT LIFE PROCESS
Pot life is the amount of time that the resin remains workable i.e. usable after addition of ammonium chloride. Take and mix properly powder 2 parts + water 1 part by weight. Then take 50 gm solution and add 2 gm solid ammonium chloride and stir continuously until the paste becomes rubbery. Note down the time, the pot life of particular paste.
The veneer surface should be properly cleaned and free from dust and other contamination. Veneer should be flat with uniform thickness. Veneers moisture content should be in between 8 to 10%. Between two adjoining veneers, moisture content should not vary more than 2%. In general, the consumption of glue varies between 300 to 450 gm per square meter based on manufacturing condition, veneer quality. The veneer surface should be properly cleaned and free from dust and other contamination. Veneer should be flat with uniform thickness. In general, the consumption of glue varies between 200 to 350 gm per square meter based on manufacturing condition and veneer quality.
PRE-PRESSING AND HOT PRESSING CONDITION
Pre-pressing is suggested to ensure uniform glue transfer. Pre-pressing panel can be handled to increase productivity as well as prevent uneven glue spraying during loading in the hot press. The specific pressure should be 2-3 Kg/cm2, pressing time varies from 15-30 minutes.
Hot pressing time and pressure varies for different wood density. Normally wood density varies from than 500 to 600 kg/cubic meter.
For wood density less than 550 kg/cubic meter, Hot Press pressure 8-12 Kg/sq.cm and for wood density more than 550 kg/cubic meter, Hot Press pressure 14-16 Kg/sq.cm Hot press temperature to be maintained between 115 to 125°C depending on the thickness of veneer and Hot Press pressure.
Hot pressing time = Basic setting time (2 minutes) (equivalent to gel time) + Heat transfer time to the farthest glue line (normally 1 minute per mm; such as for 6 mm thickness, farthest glue line is 3 mm, so ht. transfer Time to the farthest glue line is 3 minute.)
The equipment like glue mixer, spreader should be cleaned with warm water and this should be done before the glue is completely cured. The addition of slight urea to the water will facilitate cleaning process.
MAJOR APPLICATION AREAS
Plywood, particle board, MDF for an external application like civil construction, structural work. Also, it has an interior application such as doors, board-on-frame, and furniture finger joint. For the manufacture of LVL.
In the manufacture of low formaldehyde emission boards.
25 Kg packing available in HDPE bag with polyethylene liner. Also it is available in 25 Kg multi wall paper bag with polyethylene liner.
During handling powder, it is wise to use to wear hand gloves to avoid direct skin contact. Hands and another contact area to be washed with soap and hot water before a meal and when handling is over. The dust mask is also advisable.
Store in original bags in a cool and dry place and to protect from heat and moisture. The resin is hygroscopic in nature; dehumidifier may be used during storage. Bags should be closed carefully. Higher storage temperature is undesirable because it increases the viscosity of resin paste faster.
Storage life at 25°C: nearly 1 year.