When it comes to printing, copper plates are the go-to for their extraordinary printing resistance. These plates are perfect for printing and are made using the same process as other copper-zinc plates. The cosmetic hose printing machine is comprised of several critical components, including a printing plate cylinder, a rubber cylinder, an impression cylinder disc with a hose sleeve, a conveying mechanism, and an ink fountain. All of these elements work together to produce high-quality, professional-grade cosmetic hose printing.
Printing graphics and text on cosmetic hoses requires a pre-printing step where a layer of white ink or background color ink is applied to the non-ferrous metal substrate to serve as a primer. Once the background color is printed, the ink needs to dry quickly before proceeding with the printing of subsequent colors. An infrared drying device is used to ensure the ink is adequately dried before proceeding with printing the graphics and texts. The embossing roller on the embossing cylinder is covered with the hose and only rotates when in contact with the rubber roller. The embossing cylinder rotates 90° to complete the printing of a single hose, and its diameter is the same as that of the rubber cylinder, although their operation differs.
Upon completion of one week's rotation, the rubber cylinder is left behind, marking the end of the overprinting process for hose printing. The next step involves exposing the imprint to infrared rays to swiftly dry it and enhance its brightness. This method is specifically employed for printing toothpaste hoses, shoe polish hoses, and medical ointment hoses.
The ink utilized for printing on metal hoses must be capable of withstanding high temperatures and preventing fading caused by exposure to light. In addition, since metal hoses are subjected to compression and torsion stresses during usage, the ink should be able to endure water and humidity exposure. Furthermore, the ink also has to be compatible with different types of substances contained in the hose, preventing chemical erosion.
The laminated hose combines the strengths of two different materials to create a versatile and efficient hose. For example, an aluminum foil and plastic film laminated hose offers excellent resistance to moisture and weather, as well as a visually appealing appearance thanks to the ability to print on the plastic layer. Additionally, the laminated hose can be formed and processed after printing, allowing for high-quality photogravure printing on plastic. This innovative approach replaces the traditional method of curved surface printing followed by forming, resulting in the creation of laminated hoses through lamination and molding.
To overcome the issue of poor ink adhesion when printing on plastic hoses, a pre-print surface treatment is essential. Hot press transfer printing has been adopted overseas as a solution for printing images and text onto transfer paper, which is typically a coated kraft paper. The transfer paper is coated with substances that promote adhesion before printing the graphics and text. Once the transfer paper is printed, it is placed onto the curved surface and pressure is applied with heat to facilitate transfer of the image and text.