Contact angle
What is contact angle?
![Contacthoekmeting](https://www.rycobel.com/assets/uploads/site/images/_767xAUTO_fit_center-center_80_none/contacthoekmeting_170912_072009.jpg)
Contact angle is described as the interaction between a liguid and a solid. The angle between the surface of the liquid and the contact surface is called the contact angle θ.
With a contact angle being higher than 90°, the solid is not wettable.
In case the contact angle is lower than 90°, we can say the solid is wettable.
When the contact angle is 0°, there is a complete wetting.
How to measure contact angle?
![Pgx](https://www.rycobel.com/assets/uploads/site/products/pocket-goniometer-x/_767xAUTO_fit_center-center_80_none/pgx_180111_133449.png)
PGX+ contact angle analyser - Pocket Goniometer
Application: paper & pulp, cardboard
Property: absorption & cobb, contact angle - wetting angle
![Pgx Dosing Unit Pg1010 01Mr](https://www.rycobel.com/assets/uploads/site/products/pg-dosing-unit-for-pgx/_767xAUTO_fit_center-center_80_none/pgx-dosing-unit-pg1010-01mr_2021-04-08-071944.png)
PG Dosing unit for PGX+
Property: absorption & cobb, contact angle - wetting angle
![Testinkten](https://www.rycobel.com/assets/uploads/site/products/encres-dessai/_767xAUTO_fit_center-center_80_none/testinkten_180111_133551_2022-03-03-135255_ufhw.png)
Plasmatreat Testinks - Test Ink Method
Property: contact angle - wetting angle