What does the word "sanforised" mean?
"Sanforised" is the term used by manufacturers to indicate that the garment has been through some form of "pre-shrinking" process. This does not mean that there will be no shrinkage as this will depend on how the garment is washed and dried (refer to the Judogi Care section).
"Non-sanforised" means that the garment has not been "pre-shrunk", so expect more shrinkage than a sanforised garment.
Blue judogi tend to shrink less due to the dying process that they have been through.
I note that the information on belts uses the word "mercenised". What does this mean?
"Mercenised" means that the dying process used should not "run" - so will be safe to put in the washing. A separate initial soak is always a good idea before throwing in with the rest of the laundry!
What is the difference between "double weave" and "single weave"?
Judogi are sold in many “thicknesses”, which can be generally classified as either single-weave or double-weave. This refers to the weaving method used during the manufacturing process.
Single-weave judogi are thinner and weigh less (upper jacket textile fabric weight usually 300–550 g/m2). The thinner judogi are generally less durable, although some judoka may prefer them for long practices or in hotter climates as they are less likely to foster overheating.
Double-weave judogi are thicker and weigh more (fabric weight usually 650–1050 g/m2). They are harder to grab than single-weave gis, which is considered an advantage in competition. Double-weave gis shrink less and those of high quality are often sold entirely pre-shrunk. This is important to know when comparing the fit of the gi. Double-weave gis generally cost considerably more than single-weave gis of comparable quality.
Double-weave jackets designed for competition usually display a prominent seam that runs down the back of the jacket, joining two halves of fabric. Single-weave jackets usually have no back seam, or a narrow one which only joins two fabric sections without interfering with grips.
Pants by themselves should not be classified as single-weave or double-weave as the name only refers to the weaving style used for the upper section of the jacket. However, pants sold together with double-weave jackets will also tend to be heavier than normal due to stronger fabric, lining, and/or large reinforced sections.
At the end of the day, it all comes down to what you feel comfortable wearing.