Shoe size characteristics of a system of shoe sizing to be known as Mondopoint" and ISO 3355:1975 "Shoe sizes - System of length grading (for use in the Mondopoint system)". ISO 9407:1991, "Shoe sizes—Mondopoint system of sizing and marking", is the current version of the standard. The Mondopoint system is based on average foot length and foot width for which the shoe is suitable, measured in millimetres. The length of the foot is measured as horizontal distance between the perpendiculars in contact with the end of the most prominent toe and the most prominent part of the heel. The width of the
Sizing agents such as acrylic co-polymers. Surface sizing agents are amphiphilic molecules, having both hydrophilic (water-loving) and hydrophobic (water-repelling) ends. The sizing agent adheres to substrate fibers and forms a film, with the hydrophilic tail facing the fiber and the hydrophobic tail facing outwards, resulting in a smooth finish that tends to be water-repellent. Sizing improves the surface strength, printability, and water resistance of the paper or material to which it is applied. In the sizing solution, optical brightening agents (OBA) may also be added to improve the opacity and whiteness of the paper or material surface. Internal sizing chemicals used