Most sleeves are built up of a combination of an inner carbon fiber or fiberglass sleeve, a compressible inter-layer and a final aluminum shell if it is to become an anilox sleeve, or again carbon fiber or fiberglass if it is to be a plate sleeve.  It is this very combination of materials that generally leads to the issues that you’re asking about and the real issue of run out, which can only be measured with a dial indicator when pressed against the outer surface of the coated anilox sleeve or the outer wall of the plate sleeve.  

     As each sleeve ages, the inner layers are prone to delamination caused by hardening, softening, shrinkage, bond failure, or contamination from water, solvents and inks. This results in loss of concentricity between the various layers that will cause run out and in turn can lead to premature damage of the printing plate, doctor blade and will be seen visually in the printed product as uneven color densities or variations in the overall print quality of the job you are running. Unfortunately this problem can occur within weeks or months of installation dependent on how the sleeve has been run and has been handled.

     If the sleeve is dropped or knocked over, this can cause distortion and delamination within the sleeve, which will not only cause run out issues but may even prevent it being able to be slide onto the air mandrel. Again the only solution is to replace the sleeve.

     Chemical cleaning solutions have been commonly used in our industry on a daily basis. The problem with many cleaning solutions that are deemed to be effective is that they are very caustic and as a result are not environmentally friendly, are a danger to the operator and can even cause blistering of your anilox roll. EPA and OSHA standards vary dramatically by state and should be carefully followed to ensure that your company is in compliance.

     Having copies of the MSDS sheets for each solution and fully understanding the solution components will help ensure you are in compliance and that they are safe for your operator and product as well as the environment. Many solutions can have a very bad reaction with your inks so it is even worth talking to your ink vendor if you intend to try a new solution.

     All ceramic coatings have some porosity so you need to be careful with any solutions that may be very acidic or alkaline as they can and will attack the metal base; aluminum is particularly susceptible to attack by such products. If you are manually cleaning your ceramic anilox you can use stainless steel brushes to help break down any dried ink deposits.

     While blast systems have been popular, ultrasonic cleaning technology is gaining in popularity. These systems help eliminate the need for long winded manual cleaning that inevitably results in overly aggressive solutions being used to help clean rolls out of pure frustration.

    So bottom line, if your solutions have a very high or low pH then you need to investigate why and look for an alternative before you either damage your rolls, endanger your operator , impact your environment or fall foul of your state regulations.