Mjiello

Mijello´s Info´s on Tubepaints

Color Index

The color index is an international standard that indicates and differentiates colors by their materials, pigment(s), lightfastness, etc.

PW  =  Pigment White
PY   =  Pigment Yellow
PO   =  Pigment Orange
PR   =  Pigment Red
PV   =  Pigment Violet
PB   =  Pigment Blue
PG   =  Pigment Green
PBr  =  Pigment Brown
PBk =  Pigment Black



2. Lightfastness

Lightfastness refers to the character and severity of discoloration or fading when exposed to UV or visible rays.
Lightfastness is very important because completed artwork is usually expected to maintain its color and brilliance over decades, despite exposure to natural or artificial light.
Lightfastness may differ when color is added in powder form because watercolor is made by mixing pigment with medium.
Therefore, our research laboratory does not rely only on the supplier’s lightfastness test results of the colors before mixing.  For the most accurate results, we also test the final product in the tube after it has gone through the entire process of medium mixing.


Method of Testing and Indication of Lightfastness

1) Color supplier provides SGS lightfastness grade

*****          extremely lightfast
****            good lightfast
***              lightfast
**                limited lightfast
*                  less lightfast

2) ASTM 5067-99

Watercolor lightfastness using an internationally accepted method.
Ⅰ. Excellent
Ⅱ. Good
Ⅲ. Poor
Ⅳ. Very poor
Ⅴ. Foul

3) Self-test Performed by Mijello Research Laboratory

• A mixture of 1g watercolor and 0.5g water is applied to the surface of a piece of watercolor paper (8 * 5cm, weight 160g). After half is covered with aluminum foil, the paper is placed under an exposure device for 120 hours. The results are observed.

• Natural Light Test on the Rooftop
To test lightfastness, our building has installed a glass rooftop with no walls. A mixture of 1g watercolor and 0.5g water is applied to the surface of a piece of watercolor paper (8 * 5cm, weight 160g). After half is covered and sealed with aluminum foil, the paper is placed under the glass roof. The change is observed after 3, 6, and 12 months.

Of these three test results, MISSION shares the two from their pigment suppliers and ASTM. The final self-test performed by our laboratory is used internally for reference.

 
3. Indication of Transparency

The transparency of watercolor when it’s applied to watercolor paper depends on its form and density, among other characteristics.  Therefore, our laboratory tests all colors under identical conditions before indicating the transparency.

Test method :
A piece of non-absorbent paper with black stripes is attached to 160 g. of white watercolor paper. A mixture of 0.8g watercolor and 0.2g water is added to three areas of the paper to determine transparency.

* The transparency of a color depends the medium used as well as its form.


4. Staining Result

For artists that use the staining method, we have indicated the details of our staining test results.

Test method :
Different colors are mixed (0.3g watercolor and 0.1g water) and applied to a 5 * 5cm area on a piece of watercolor paper. After 24 hours, the surface is rubbed with a wet brush and dabbed with dry pulp.

The unique characteristics of these watercolours is the unparalleled colour strength max. pigmentation. And while this high colour strength requires a slightly different approach on the part of the aquarellist  little paint  to get used to the ratio of paint to diluent, the advantages are clear.

more Watercolor paintings

fresh from the easle...