A mechanical pencil is a type of pencil that has a button on the end. It looks like a ballpoint pen, but is made of different materials. It's a great option for architects, draftsmen and people who need flexibility. The components of a mechanical pencil are usually made from a combination of high c...

A marker pen is a pen that can write marks or signs on one or more materials such as paper, wood, metal, plastic, and enamel. Markers are divided into oil-based markers and water-based markers. Water-based marker pens can write on smooth surfaces or whiteboards, and can be wiped off with a rag, whil...

The falling core type automatically produces the core by the gravity of the core. The rotary type conveys the core by rotation. The pulsating type (pushing type) conveys the core by pressing, and the structure has a single pressing type, that is, the core is delivered by pressing once. The double-pr...

Are crayons safe? Crayons are made up of solvents, solvent-soluble polymers, glass pigments, and gelling agents. Many chemicals are added during the production process. If they are only used for drawing, as long as they are purchased from regular manufacturers, they are of good quality. All crayons ...