Digital Magazine

Barrier Layer Protects CDs from Skips and Scratches

Optimanufacturing is turning out a new product designed to protect the surface of a compact disc. A unique laminating process makes it work.

Compact discs (CDs), once thought primarily for music, today are used to store software programs, data, games, and more. There is now a product that will protect these precious bearers of information and entertainment from the scratches and skips that may occur during everyday use and transit.

Manufactured with a unique, proprietary lamination process, the CDfender is a three-part product (polyester/polycarbonate/polyester) designed to protect the playing surface of the CD. (Material suppliers are proprietary.) Under normal handling and storage circumstances, CDfender reportedly will adhere to a CD-ROM, game CD, or music CD and will provide that disc with a protective barrier against minor damage that might affect the playback functionality of the media.

From Houseboat to CD
The idea originated with Trevor Burroughs, technical director at Optidisc Inc., London, England. Burroughs spent months studying CD technology, looking for a simple, inexpensive way to protect the discs. He came up with the idea for a clear polycarbonate film that would have the same properties as the CD itself, allowing the laser to read through the film.

Burroughs determined he would need an adhesive to bond the film to the CD in order to prevent air from being trapped between the two layers. His search for an adhesive with the necessary properties ended when it occurred to him that a variation of the clear sealant he was using to patch the leaky roof of his houseboat might work for his invention, too.

His idea came to fruition through a partnership between Optidisc and Integrated Design Co. (IDC), a custom machinery manufacturer located in Green Bay, WI.

In 1997 Optidisc approached IDC to build a die-cutting machine for the manufacture of its new product. Realizing IDC's machinery capabilities, Optidisc awarded it the contract for all of the machinery involved in this patented process. In 1998 Integrated Design entered into an agreement not only to design and build the machinery but to manufacture the end product as well.

This gave birth to a new company, Optimanufacturing, which opened its doors Jan. 1, 1999. Now, all products for worldwide distribution are manufactured out of its 13,000-sq-ft facility in Green Bay and marketed out of the U.K. and US offices.

Each Layer Plays a Part
The CDfender is made up of three separate layers. The PC layer that adheres to the CD is sandwiched between two printed polyester layers. According to John Brabender, VP of manufacturing at Optimanufacturing, "The polycarbonate is actually the product itself. This particular polycarbonate is very unique in that it's an optical grade. It doesn't have any imperfections that could bend the light going through it, so the product does not affect the audio or visual quality of the CD. The two polyester layers are just for application and handling; they are peeled off and discarded when you apply the product."

The polyester layers, however, do serve a dual purpose. Working in conjunction with the instruction booklet for proper application to the CD, one is printed with the number 1 and the other with the number 2. The layer on side 2 also protects the adhesive-like substance that adheres the disc to the CD.

Brabender explains, "You can call it an adhesive, but it's not a true adhesive because of its nature. It's a solvent-based material that we call an optical couplant. It kind of acts like a drop of water between two pieces of glass. If you touch it, you wouldn't feel any adhesion to it. It really only sticks very smooth things to each other, which is the polycarbonate film and the CD itself."

There are two separate lamination steps, both occurring on laminating lines designed and built by Integrated Design. In the first step, one of the polyester layers is coated and then laminated to the PC film on a 62-in. wide flexographic coater. The film is then slit into three rolls, 20 1/2 in. wide, on equipment manufactured by Parkinson.

The second laminating step takes place in a class 10,000 clean room. This lamination is especially important, as it applies the proprietary adhesive-like substance that will adhere the product onto the CD.

"Those slit rolls are taken to a separate machine," says Brabender, "which is a 201/2-in.-wide solvent coater/laminator located in the clean room. That two-part lamination is coated again, and the third polyester layer is laminated to that. The finished roll is taken to the die-cutter where it's printed one color, both sides, and die-cut." That IDC equipment, which runs at 300 fpm, uses all ultraviolet flexo inks.

Treaters Have Key Role
Throughout the process, all three layers are treated selectively for adhesion using two universal roll corona treating stations from Enercon Industries.

Optimanufacturing purchases pretreated film, but Brabender explains that treatment levels on pretreated film are not stable. "We treat in-line for uniformity in the lamination process. There are two different coatings used, one for each side. We want the coatings to stay with a particular layer, because when you peel apart the product and throw away the polyesters, one coating is designed so it will stick to the polyester only and be thrown away. The other one's designed so it will stick to the polycarbonate, so when the polyester's peeled off, the coating doesn't come off with it. The corona treatment is a key for that."

After the product is die-cut into its disc shape, it is bulk packed for shipping to fulfillment houses and packaged for retail sale.

In its first year, Optimanufacturing produced millions of pieces at its new facility. "We launched in October of last year in the U.K. and Europe," says Brabender. The CDFender hit the US market early this year. Next up for this start-up firm will be DVDfender, manufactured specifically for the DVD format and projected to debut in the US this year.
Supplier Information
Integrated Design Corp
, Green Bay, WI; 920/434-4141

Parkinson Machinery & Manufacturing, Woonsocket, RI; 401/762-2100

Enercon Industries, Menomonee Falls, WI; 262/255-6070; enerconind.com

Subscribe to PFFC's EClips Newsletter