GUM TRAGACANTH (KATIRĀ)

Gums are utilized not only as adhesives but also as paint binders and sizes. In general, gums exhibit relatively weaker adhesive properties and can be distinguished from natural resins by their solubility. Resins typically dissolve in organic solvents, while gums are typically water-soluble. Two sizing materials mentioned in Persian historical treatises that fall into this category are gum tragacanth (katirā), gum arabic (samḡ-e arabi), and eremurus (seriš).

Recipes:
In Persian historical sources, only two texts, namely Jamali-ye Yazdi (580 A.H./1184 A.D) and Teflisi (12th century), mention the use of gum tragacanth for sizing paper. In their recipes, after explaining how to make size from rice, both authors recommend gum tragacanth and starch as suitable alternatives. Additionally, to safeguard the paper from biological deterioration caused by flies and mice, they suggest adding Citrullus colocynthis (hanzal) to the size. Jamali-ye Yazdi specifically notes its effectiveness against flies and mice. Teflisi’s recipe belonging to 12th century, reads as follows:  

اگر با کتیرا یا با نشاسته وی را گونه دهد هم روا بود. و اگر خواهد که موش کاغذ که گونه میدهد تباه نکند آب شحم حنظل با وی بیامیزد و کاغذ را بدان گونه دهد

It is also acceptable to size the paper with tragacanth or starch. If one wishes to safeguard the paper from potential damage caused by mice, mix it with an extract of Citrullus colocynthis (hanzal) before applying the size to the paper in this manner.

Jamali-ye Yazdi in his recipe belonging to 12th century, besides rice, starch and gum tragacanth he has mentioned wheat flour as other option as well. The recipe in Farrokhnameh reads as follows:

و اگر نیکوتر باید به کتیرا یا به آرد (میده) یا (به) نشاسته گونه باید داد. و اگر شحم حنظل با آن بیامیزد مگس بر کاغذ ننشیند و موش زیان نکند

If a finer sizing is desired, the paper can be treated with tragacanth, wheat flour, or starch. Adding citrullus colocynthis (hanzal) to the mixture prevents flies from settling on the paper and protects it from mice damage.