MELAMINE-UREA ADHESIVE 1247
To be used in the production of load-bearing timber structures, finger joints and blockboards. 1247 with hardener 2526 is used for applications in the wood working industry, where there is demand for light-coloured bond-lines with high water and weather resistance.
1247 with hardener 2526 is tested and approved for the production of load-bearing timber structures by Norsk Treteknisk Institutt (NTI), Norway, Centre Technique du Bois et de l´Ameublement (CTBA) France, Materialprüfungsanstalt Universität Stuttgart - Otto-Graf- Institut - (MPA), Germany and SKH/KOMO (DHBC 32389), Holland according EN 302 part 1 to 4 and DIN 68141 with adhesive:hardener ratios of 100:100 to 100:20 parts by weight (pbw).
1247 with hardener 2526 is also approved by BUtgb (ATG 06/2662) in Belgium.
1247 with hardener 2526 fulfils with all adhesive:hardener ratios the requirements for use in the production of load-bearing timber structures according EN 386 and DIN 1052.
1247 with hardener 2526 is approved by the above institutes for separate application of adhesive and hardener but is also approved to be used as an adhesive mixture. When adhesive and hardener are applied separately, only Casco Adhesives´ Separate Ribbon Spreader 6230 is allowed to be used.
Type 1247 Melamine-Urea-Formaldehyde adhesive
Delivery form 1247 liquid
Colour 1247 white
Viscosity Measured with Brookfield LVT, sp.4, 12 rpm, 25ºC.
1247 approx. 15000 mPas at the time of delivery
Measured with Brookfield LVT, sp.4, 60 rpm, 25ºC.
2526 approx. 2200 mPas at the time of delivery
Density 1247 approx. 1250 kg/m³
2526 approx. 1070 kg/m³
Dry solids 1247 approx. 63%
pH 1247 approx. 10
2526 approx. 1.7
Flash point 1247 above 100°C, not flammable
2526 above 100°C, not flammable
Free formaldehyde 1247 approx. 0.5%
Properties of the 1247 with hardener 2526 fulfils the requirements
bondline according EN 301 (for adhesives of type I and II, service classes 1, 2, 3), EN 386 and DIN 68141.
Storage life and 1247 4 months at 20°C in well closed packaging.
conditions for storage 2526 4 months at 20°C in well closed packaging.
The viscosity will increase during storage and the increase will be faster at the end of the storage life. Higher temperatures will also shorten the storage life. At 30°C the storage life will be approximately half of the storage life at 20ºC.
The most suitable storage temperature is around 20°C for both products. The adhesive shall not be stored at temperatures below +10°C and the hardener shall not be stored below +18°C. Both products shall not be stored in temperatures above +30°C. Short time exposure to temperatures below +10°C and above +30°C for both products e.g. during transportation can be accepted.
If the products have been frozen they cannot be thawed and
used because of irreversible changes in their properties.
Moisture sensitivity None
DIRECTIONS FOR USE
Application tools Casco Adhesives’ Separate Ribbon Spreader 6230 when adhesive and hardener are being applied separately. Otherwise roller spreader or ribbon spreader can be used.
Mixing ratio 1247 100 parts by weight (pbw)
2526 20-100 parts by weight (pbw)
Please notice that the allowed adhesive:hardener ratios by BUtgb in Belgium is for the moment 100:100 down to 100:50 pbw. Approval for the ratio 100:20 is pending.
The accuracy in the hardener amount shall be ±2 pbw both when the adhesive and hardener are used in separate application or as a mixture.
The most suitable temperature for use is 17-25°C.
Temperature of The temperature of the wood material should not be
wood below 20°C when adhesive and hardener are applied.
Pot life Pot life is the period of time during which the mixture of adhesive and hardener can be used after mixing the components. When 1247 and hardener 2526 are used as a mixture the pot life at 20°C is approx. 40 min with 20 pbw of hardener, approx. 15 minutes with 50 pbw of hardener and approx. 8 minutes with 100 pbw of hardener.
When 1247 and 2526 are used in separate application no problem with pot life will occur since adhesive and hardener are not mixed until being applied on the surfaces to be bonded.
Moisture content 8 - 15%. For the production of laminated beams 10 - 12%
of wood is recommended.
Planing of wood Newly planed surfaces give the best gluing result. For best result in laminated beam production the timber must be smoothly planed. For optimum bonding strength the planing should take place within 24 hours before gluing.
Adhesive spread For production of laminated beams an adhesive spread of at least 300 g/m2 single-sided is recommended. A reduction of the adhesive spread , e.g. at very short assembly times, is only allowed to be done together with Casco Adhesives´ Technical Advisors and depends on the production parameters for the production line in question. This optimization implies that the set parameters are followed and that a continuous control of the bonding quality is made by means of delamination tests. At high frequency (HF) gluing operations an adhesive spread of 250-350 g/m2 single-sided is recommended. For other applications: 150-300 g/m2.
Well planed and smooth surfaces and short assembly time require less adhesive than rough surfaces and long assembly time. Difficult-to-glue wood or hardwood may require double spreading in amounts of approx. 250 g/m² on each side.
Assembly time Assembly time is the time between spreading of the adhesive and the moment when the material to be bonded are put under pressure in the press. It consists of an open assembly time (OAT) and a closed assembly time (CAT). The OAT is the time between adhesive application and assembly of the pieces to be bonded. The CAT is the time between assembly of the pieces to be bonded and the initiation of pressure in the press.
The pressure must be applied while the adhesive is still tacky.
The assembly times are influenced by the adhesive spread, the method of applying the adhesive, the temperature and relative humidity in the working area, the wood species, the moisture content and the temperature of the wood etc. The assembly times and the press times are prolonged when the adhesive spread is high, the temperature in the working area is low, the moisture content in the air is high and the wood is slowly absorbing the water in the adhesive.
For questions under specific working conditions our Technical Advisor should be contacted.
Closed assembly time In the table below the approximate closed assembly times with single sided adhesive spread and with separate application of adhesive and hardener are given for soft wood e.g spruce.
Adhesive spread with 400 g/m2, single sided, with 20 parts by weight of hardener
Maximum CAT (minutes) 120
Minimum CAT (minutes) 5
Adhesive spread with 400 g/m2, single sided, with 50 parts by weight of hardener
Maximum CAT (minutes) 80
Minimum CAT (minutes) 5
Adhesive spread with 400 g/m2, single sided, with 100 parts by weight of hardener
Maximum CAT (minutes) 50
Minimum CAT (minutes) 5