When domestic aircraft carriers are developing by leaps and bounds, when domestic high-speed railways are competing for orders from the world, when domestic large aircraft are unveiled Landmark domestic high-end equipment is constantly
Performance and technical requirements of neutral ink
Although the neutral ink pen belongs to ball point pen products, its writing principle, pen head structure and t addition_ 32 art is similar to traditional oil ballpoint pen, but due to the difference of ink performance, there are spec
As an important part of the fluorescent board, the fluorescent pen plays a great role in the display process. It is used to write and draw the information that you want to publicize, the instructions for the use of the fluorescent pen
? ? ?The development history of ballpoint pen has been published for thousands of years. There were pens in Chinese characters. People carved words on bone plates and bamboo slips. They used knives called "knives and pens". Since