Roll stock
What is roll stock?
A rollstock definition for buyers: what roll stock packaging is, how it runs on VFFS and HFFS, film structure at a general level, print, and how to spec an order.
Definition
Roll stock, also written rollstock, is flexible film wound on a core and supplied as a roll. Roll stock packaging is the package your machine makes from that film. The converter prints, slits, and winds the web. A vertical form fill seal machine, a horizontal form fill seal machine, or a similar line forms the package, fills it, and seals it. A premade pouch arrives already formed. Roll stock does not.
Poly Craft Industries (PCI) prints roll stock by flexography on two 10 color flexo presses (Uteco) and describes its flexible packaging as made in the USA. PCI is SQF certified and GMI certified. Standard lead time is 3 to 4 weeks after artwork approval. The buying guide for repeats, widths, and the quote is the roll stock page. Ordering custom printed roll stock for a VFFS or HFFS line is on the printed roll stock page. This page is the definition.
What roll stock is
A roll is a continuous web. Web width is the width across the roll, from edge to edge. Repeat, sometimes called cutoff, is the length along the web for one package. Those two dimensions are not interchangeable. How to measure them, and how unwind direction and roll geometry fit a machine, is on the web width, repeat, and unwind page.
The film may be printed or unprinted. Printed roll stock carries your artwork on the web, including the eye mark the machine uses to keep each cut with the print. Unprinted roll stock is the same supply form without graphics.
How roll stock runs on VFFS and HFFS
On a vertical form fill seal machine, the film is pulled over a forming collar, shaped into a tube, filled from above, and sealed. The back seal is a fin or a lap, and the repeat follows the bag length. On a horizontal form fill seal machine, the film and the product move horizontally, and the web width, cutoff, and seal style follow that setup. The two machines do not share one roll spec.
PCI sells the film, not the machine. Send the machine make and model before anyone treats a structure as a match. The checklist for web width, unwind, core size, eye marks, and film structure is the printed roll stock for VFFS and HFFS page.
Film structure, at a general level
Film structure is the list of layers and the job each layer does. A roll can be a single film, or a laminate of more than one film bonded together. One layer is usually the sealant, the part that has to seal on your jaws. Other layers may add stiffness, a surface for print, or a barrier to moisture, oxygen, light, or odor. Which of those you need depends on the product, how it is filled, and the shelf life you are trying to hold.
A material name is not a finished structure. If you know the layers, send them. If you do not, send the current specification or an unused sample and say the structure is unknown. Do not guess the layers from how the film looks. Barrier data, when you have it, needs the test conditions that go with the number.
Custom printed roll stock is the same film with your artwork. PCI prints by flexography on two 10 color flexo presses (Uteco), so one pass can carry up to ten inks. Surface print puts the ink on the outside of the film. Reverse print puts the ink on the inside of a clear web so a laminate can bury it. Which one you need comes from the current specification, not from a photograph.
Send the artwork when you have it. If the art is not ready, send a color count. The quote is confirmed when the artwork is approved. How buyers write that print into a roll spec is on the custom printed roll stock page. Ordering that printed film is separate from this definition.
How to spec and order
A useful order names the product, the machine, the roll, the structure or a sample, and the print. PCI publishes its address as 36-60 Industrial Place, Middletown, NY 10940, and describes its flexible packaging as made in the USA. PCI is SQF certified and GMI certified. SQF is the food safety certificate. GMI is the print quality certificate. PCI supplies brands sold at major retailers. Confirm that the site named on the certificate is the site that will run the job.
| Spec | What to send | Why it is on the order |
|---|---|---|
| Product | What you pack, and how it is filled | The film has to suit the product and the line |
| Machine | Make, model, and whether the line is VFFS or HFFS | The roll is built for that machine |
| Web width | Width of the film from edge to edge | Not the same as the finished package width |
| Repeat | Length of one printed package along the web | Also called cutoff when that is the term on your spec |
| Unwind | Which way the print faces as the film leaves the roll | Copy it from the current roll label or the machine |
| Core and roll size | Core inside diameter, and the largest roll the machine accepts | A correct film on the wrong core does not run |
| Structure | The layers, if you know them, or a sample | Do not guess the layers |
| Artwork, or a color count if the art is not ready | Lead time is 3 to 4 weeks after artwork approval |
Lead time is 3 to 4 weeks after artwork approval. It does not start at the first email. Send what you have. Email Matt@PolyCraftInd.com or call 516-849-6237.
Questions buyers ask
What is the rollstock definition?
Roll stock, also written rollstock, is flexible film wound on a core. Roll stock packaging is the package a filling or wrapping machine makes from that roll. The film may be printed or unprinted.
What is roll stock packaging?
Roll stock packaging means the package is formed on your line from film on a roll. The supplier supplies the film. Your machine forms, fills, and seals it. A premade pouch arrives already formed.
Is rollstock the same as roll stock?
Yes. The industry uses both spellings for the same supplied web.
How does roll stock run on a VFFS or HFFS machine?
A vertical form fill seal machine pulls the film over a forming collar, makes a tube, and fills from above. A horizontal form fill seal machine moves the film and the product horizontally. Web width, repeat, unwind, core, and the sealant have to match that machine. PCI sells the film, not the machine.
What is a film structure?
Film structure is the list of layers and the job each layer does. A roll can be one film or a laminate of more than one film. One layer is usually the sealant. If you do not know the structure, send the current spec or a sample and say it is unknown.
How is roll stock printed?
Printed roll stock carries the artwork on the film. PCI prints by flexography on two 10 color flexo presses (Uteco). Send the artwork, or a color count if the art is not ready.
What should I send to spec and order roll stock?
Send the product, the machine make and model, web width, repeat or cutoff, unwind direction, core size, the largest roll the machine will accept, the structure or a sample, artwork or a color count, order quantity, annual usage, and the ship-to location.
How long does printed roll stock take at PCI?
PCI's standard lead time is 3 to 4 weeks after artwork approval. The window starts when the artwork is approved.
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