Gel pen is tasteless, the nib is not easy to dry, and the writing is light-resistant but not waterproof.
The carbon pen will render when it meets water, and it will be easily cut off if it is accidentally dropped.
2. The structure of the nib is different.
The nib structure of gel pen is basically similar to that of carbon pen, except that pen and ink are neutral, that is, it is not oily ink. When stored in a pen tube, they are gelatinous, but once written, the handwriting is partial. So expressive force is better than carbon pen.
3. The refill has different characteristics.
The substance in the refill of carbon pen and gel pen is different in nature. The substance in the refill of carbon pen is oily, while the substance in the refill of gel pen is aqueous.
4. Different expressive force
The tip of charcoal pen is characterized by walking ball structure, which can write 360 degrees. Moreover, the ink used is oily and slippery, which has very limited expressive force on calligraphy, while the reverse side of the words written by gel pen has no obvious word marks, because gel pen does not need too much power to write.
Baidu encyclopedia-carbon pen
Baidu encyclopedia-gel pen