Method and apparatus for preventing pigment buildup during a rotary screen printing process

An apparatus for preventing excessive pigment buildup on at least one prescribed portion of the exterior surface of a rotary printing screen in a region adjacent the edge of fabric being printed comprising:

• a. at least one flexible wiper member including a means to bias the flexible wiper member against said at least one portion of the exterior surface of the rotary printing screen and positioned in the excessive pigment region wherein said flexible wiper member is angled less than about 45 degrees with respect to the axis of rotation of the rotary printing screen so as to push the excessive pigment buildup away from the fabric being printed;
• b. a lubricant stream delivery system comprising:
• i. at least one lubricant delivery line;
• ii. at least one bendable conduit in fluid communication with said lubricant delivery line;
• iii. a nozzle mounted on said bendable conduit wherein said nozzle is adapted to apply a lubricant stream to the exterior surface of the rotary printing screen;
• and
• c. wherein the excess pigment is removed to clean the portion of the screen exterior surface after the printing of said fabric.

An apparatus for preventing excessive pigment buildup on at least one prescribed portion of on the exterior surface of a rotary printing screen in a region adjacent the edge of fabric being printed comprising:

• a. a preliminary flexible wiper member including a means to bias the flexible wiper member against said at least one prescribed portion of the exterior surface of the rotary printing screen and positioned in the excessive pigment region wherein said preliminary flexible wiper member is angled less than about 45 degrees with respect to the axis of rotation of the rotary printing screen so as to push a major portion of the excessive pigment buildup away from the fabric being printed;
• b. a primary flexible wiper member positioned downstream of said preliminary flexible wiper and biased against the exterior surface of the rotary printing screen wherein said primary flexible wiper is positioned in the excessive pigment region and is angled less than about 45 degrees with respect to the axis of rotation of the rotary printing screen so as to push a remaining portion of the excessive pigment buildup away from the fabric being printed;
• c. a lubricant stream delivery system comprising:
• i. at least one lubricant delivery line;
• iv. at least one bendable conduit in fluid communication with said lubricant delivery line;
• v. a nozzle mounted on said bendable conduit wherein said nozzle is adapted to apply a lubricant stream to the exterior surface of the rotary printing screen;
• and
• d. wherein the excess pigment is removed to clean the prescribed portion of the screen exterior surface after the printing of said fabric.

An apparatus for preventing excessive pigment buildup on at least one prescribed portion of the exterior surface of a rotary printing screen in a region adjacent the edge of fabric being printed, comprising:

• a. a preliminary flexible wiper member biased against said at least one prescribed portion of the exterior surface of the rotary printing screen and positioned in the excessive pigment region of said prescribed portion wherein said preliminary flexible wiper member is angled to the axis of rotation of the rotary printing screen at an angle of less than about 45 degrees;
• b. a first mounting bracket for holding said preliminary wiper member in a predetermined orientation with respect to the exterior surface of the rotary printing screen;
• c. a primary flexible wiper member positioned downstream of said preliminary flexible wiper and biased against the exterior surface of the rotary printing screen and positioned in the excessive pigment region of said prescribed portion wherein said primary wiper member is angled to the axis of rotation of the rotary printing screen at an angle of less than about 45 degrees;
• d. a second mounting bracket for holding said primary wiper member in a predetermined orientation with respect to the exterior surface of the rotary printing screen;
• e. a tensioning system attached to said first and second adjustable mounting brackets for biasing said preliminary and primary wiper members against the exterior surface of the rotary printing screen;
• and
• f. first and second systems for applying lubricant to the outer surface of the rotary printing screen adjacent to and upstream of said preliminary and primary wiper members respectively.