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Question and Answer

Overprinting on White Foil

by Staff

May-June, 2013
Overprinting white pigment hot stamping foil can add an interesting and dramatic look to a printed piece, especially on an uncoated stock where the printed element stands out and keeps its brilliance as if it was printed on a coated surface. This topic was addressed through recent email conversations on the Foil & Specialty Effects Association’s HelpLinks, and InsideFinishing has gathered several of the comments and suggestions for proper procedures when foil stamping white foils on overprinting applications.

Q: What recommendations are there for foil stamping a large, solid area of white foil onto an uncoated cover (such as Kraft Speckletone) and then overprinting it using offset printing?
The goal when overprinting the white foil area on an uncoated sheet is to allow the offset printing to maintain its true color on the dark paper, much like the results produced when overprinting silver foil. According to Larry Ambrosius, Independent Printing Company, Inc., the key to successfully overprinting a foil stamped image area of approximately 2" x 2" is to try to keep from debossing the image too far into the sheet. This is a delicate balance of getting the proper coverage of the white foil and not pressing the image area in too far. If the image area is debossed too deeply, the inks will not properly cover around the edges of the foil stamped square. “The lighter the hit the better, as long as the foil doesn’t start ripping off onto the press blankets,” stated Ambrosius.

“We have successfully completed many projects with this technique over the years, and we have not had issues with ink not covering the corners or edges,” said Paul Adametz, The Letterpress Shoppe. He said that his company typically has used a gloss white, but it also has used a cream-colored foil, which produced a warmer and softer color on the overprint. (Projects from the Letterpress Shoppe are featured above.) Most of the company’s projects have been on large sheets and have run on a Brausse handfed press, but The Letterpress Shoppe also has run overprinted pieces on a Strathmore Grandee with a solid area as large as 4x5".

Q: Is it better to use gloss or matte white pigment foil?
Greg Greenwald, Scarab Printing Arts, said he’s used both gloss and dull white pigment with great results. His company also has successfully stamped white pigment onto a plastic sheet and then overstamped and printed. Regardless of the foil choice, Greenwald advised to make sure that the foil passes the tape test. “A simple tape test on the entire foil stamped area will determine if the foil has been properly applied in all areas of the image,” stated Greenwald. “Even if the foiled area looks to have complete coverage, there may be low spots that need to be built up on the makeready.” Making sure the foil stamped image adheres properly to the sheet is important in all applications. However, it is even more important in an overprinting job where the foil is subject to the offset blankets on the printing press.

Q: What suggestions should the foil stamper provide to the printer when working with white foil and overprinting?
Dave McIntosh, McIntosh Embossing, recommended that the foil stamper communicate with its printer that there will be more waste with this type of job than a normal print job. “When stamping and overprinting on an uncoated stock, the foil has a much greater tendency to pick off onto the printing plates,” stated McIntosh. “Printers need to be made aware of this since they will be cleaning blankets far more often than they want to, and the ink may not always settle into the edges of the foil impression.”

Ambrosius also recommended communicating with the printer that there are special printing blankets available to help prevent the foil from sticking to the press blanket. Adametz of The Letterpress Shoppe highly suggested telling the printer to use a mild, less aggressive blanket wash. “We have completed many projects using this technique over the years, and our solution to eliminating any foil transfer has always been the printer using a mild blanket wash. We have never had to rerun an overprint project,” Adametz said.

Ambrosius added that using UV inks also can be desirable because they dry instantly with no risk of setoff. However, this is not always an alternative for the printer. There are special inks for overprinting foil that should be used in these applications.