Soft roller (commonly referred to as cot), it is generally used vulcanized natural rubber, synthetic rubber, polyurethane, gelatin and polymer made; hard roller (commonly referred to as metal rolls), usually with iron , copper and other metal materials. Rubber roller and a metal roller itself has good lipophilic, so as to ensure good ink is provided on its surface wetting and adhesion, which is to ensure the ink between the ink transfer roller. Cots refers to metal or other material for the core, covered with vulcanized rubber made of roll-formed products. Ink roller printing machine is mainly used to transfer ink. In order to make the ink between the ink roller rapidly and uniformly distributed open, usually with soft roller and a hard roller alternately arranged on the press, the adjacent roller produce good contact. First, the manufacturing process Cots: The main raw materials, including polymers, curing agents, plasticizers, fillers, accelerators; primary process and the role: Mixed - Filter - curing process - grinding - polishing. 1, Mixed: controls the content of the ingredients, heat drying temperature, hardness, composition and stability. 2, filter: colloid uniform, no impurities. This is particularly important for high-speed printing machine: even in high-speed operation force, energy transfer due to various factors even when expansion or contraction, can maintain uniform, so that adjustment can only rely reduce or avoid adverse effects. 3, the cure: through heat and pressure and curing process, stabilizing gifts accelerant, rubber by an external force to minimize the degree of contraction. The soft and malleable into solid compounds, and have a certain softness of the material, and thus more suitable for delivery and transfer of the ink. 4, grinding and polishing: to determine the key Cots dimensional accuracy and surface area, especially alcohol water roll the arc process. Rubber surface looks smooth, but under high magnification, there are many small convex and the concave portion. These projections and recessed portion increases the surface area cot, so that it has excellent ink transfer, the transfer performance. This process requires a constant temperature: the temperature is too high, the surface is easy charring, short print will appear peel phenomenon. Temperature is too low, the local brittle, resulting in ink transfer performance. Second, Cots performance requirements: 1, inclusive - on water, ink affinity and capacity; 2, elastic - can show whether the pressure is correct; resilient performance was good pressure; 3, the indentation reflects the - correct adjustment of printing pressure basis; 4, vibration absorption - Prevents jumping up and down, resonance (high speed); 5, abrasion resistance - maintain a high surface area, anti-caking ability glaze, and inclusiveness is maintained; 6, energy transfer properties - not ensure their own accumulation of energy, does not reflect energy; 7, corrosion resistance - good chemical resistance, helping to extend life; 8, conductive - anti-static, no adsorption of the ink and paper hair; 9, heat transfer - to extend the shelf-life reducing the pressure of time to adjust; 10, high temperature - to extend the life of rubber roller itself (especially for high-speed machines). Third, the rubber roller hardness: the hardness of the rubber roller is an important manifestation Cots performance, specific performance is as follows: 1, soft - inclusive, and flexible, strong resilience and vibration absorption is good, reflecting good impression on the pressure regulator range. 2, there is a certain hardness - less susceptible to corrosion and wear resistance, high temperature capability, pressure performance rapidly so, cot hardness need moderate: too soft, anti-corrosion ability, easy to gather energy; excellent ink transfer capacity decreased, vibration absorption is poor, Easy undermine presses sophisticated design. So, we need to select the correct type and hardness of rubber under the appropriate printing pressure and other printability.