While checking on whether the quality of the individual product batch conforms with the parameters declared, the following three chracteristics are being assessed. They are:
However, there are different procedures to determine these parameters and they may not provide identical final results. This is why we, hereby, give you the ones we have been using in our laboratory. To check on the quality of our products we naturally utilize other methods too, yet we consider them to be our internal affair only.
At the request of our customer we then issue a document “The Certificate of Quality“ for each batch in which we specify the values reached.
The fundamental standard to determine this parameter is ČSN EN ISO 3251 – Paint materials and plastics – determining the content of involatile fractions. This standard is a Czech language version of the EN ISO 3251:2003 standard.
Note: For some practical reasons we opt to make slight deviations from the standard.
The content of involatile fractions to be calculated according to the following formula:
NV = (m2 - m0) / (m1 - m0) x 100
|is the percentage content of involatile fractions|
|is the weight of the empty dish in grams|
|is the weight of the dish with the test sample in grams|
|is the weight of the dish with the remainder in grams|
Prescribed values for individual lacquers
|PRIMER VIKTOR 400, 442||80°C||1 hour|
|ALL THE OTHER LACQUERS||105°C||1 hour|
The value measured is given in weight percentage with the accurracy of 0,1%.
The procedure is based on the ČSN EN ISO 2431 standard – Paint materials – determining the discharge period through outflow crucibles. This standard is a Czech language version of the EN ISO 2431:1996 standard.
Note: For some practical reasons we opt to make slight deviations from the standard. Primarily, the outflow crucible does not altogether conform with the standard; the outflow nozzle is different length. The standard demands the length to be 20 mm. Our company utilizes one which has 4 mm in length and 4 mm in diameter. The aim here is to reach compatibility with the measurement procedures in our customers. As far as we know, they all use crucibles with the ø 4mm x 4mm nozzle.
The measurement temperature: 20 ± 2°C.
Note: The consistency of some lacquers may be partly altered in the course of time. This is why there may be deviations from the values declared in the Certificate of Quality.
The resulting value is given in seconds at the temperature of 20 ± 2°C.
The value measured is given with the accurracy of the whole seconds.
The procedure is based on the ČSN EN ISO 2811-1 standard – Paint materials – determining the density – Pycnometric method. This standard is a Czech language version of the EN ISO 2411-1:2001 standard. We apply a Gay-Lussac 25 or 50 ml pycnometer.
The lacquer´s density ρ expressed in grams per mililiter at the test temperature of 20 ± 0,5°C shall be calculated according to the following equation.
ρ = (m2 - m1) / Vt ,
|where||ρ||- density expressed in grams per mililiter|
|m1||- weight of empty pycnometer in grams|
|m2||- weight of pycnometer with the test sample at 20 ± 0,5°C in grams|
|Vt||- volume of the pycnometer in mililiters at 20 ± 0,5°C.|
The value measured is given with the accurracy of 0,01 grams per mililiter.