Get the right lamps for the plates you use
Traditional metal printing plates require exposure by "diazo" light, which peaks in the range of 410 nanometers (nm). A variety of newer plates, including Spectratech's Peerless KemFre and Kodak's V-360, Citiplate's Aqua LHP, Konica's Replica Newsplate and their Duros KNS, Macdermid and others require "photopolymer" light in the range of 320 - 380 nm, with a peak around 365 nm.
Since diazo has long been the standard in the printing industry, the lamps installed in most platemakers do not emit enough photopolymer light to properly expose these new plates. Although some of the newer "multi-spectrum" lamps do produce light at 365 nm, the intensity is often not high enough.
For optimal exposure, you must change to a lamp that provides the light the plates need to "see". In some cases, there are plug-compatible replacements for your existing lamp, and in others, you must change settings on the control panel or in the machine, to accommodate the switch. In some cases, there are no photopolymer replacements available.
Before you change lamp types, it is imperative that you speak with a technician from the equipment manufacturer to avoid damaging your equipment.
You may also need to change the probe or the filter on the integrator, so that it reads the light the same way your plate does, to insure consistent exposure times over the life of the lamp.
Since the UV output of platemaker lamps declines over time, even a lamp of the correct type may not give you enough intensity in the critical photopolymer area, if the lamp is old. Also keep in mind that the photopolymer output of some multi-spectrum lamps will decline more quickly than the diazo component, leading to shorter effective life, when using these multi-purpose lamps.
Here are recommendations for the most popular platemaking systems:
Replace L-1250 with L-1252 or L-1261
Replace L-1280 with L-1282 or L-1281
Replace LY-33 with MH-153
Replace KT-38 with PM-78
Replace HT-121 with HT-162
NP-80 may be used with no change
NOTE: The GW-114, JQ-30, CN-42, and CU-71 may not emit enough photopolymer light for proper exposure, and there is no replacement lamp.
Replace THS-8020 with THS-8027 (multi-spectrum)
Replace THS-5020 with THS-5027 (multi-spectrum)
Replace THS-6020 with THS-6027 (multi-spectrum)
NOTE: Generally, Theimer lamp numbers ending with a "7" are multi-spectrum, which those ending in a "0" are diazo.
Replace 1406-01 (754-18013) with 1406-02(754-18014)
Replace 1406-04 (754-18015) with 1406-05(754-18016)
NOTE: The 1406-07(754-18054) is a multi-spectrum lamp and will give adequate results, but the 1406-05 is photopolymer and is better suited.
Replace 10265 with 10700
NOTE: The 10266 and 10431 have no photopolymer equivalents.
Call or email us for recommendations on any other equipment you have, or if you have any questions on the suggestions above.
Remember: You always save money with Caprock lamps, compared to the high-price alternatives from the manufacturer of your equipment!