Which film is right for me?
PVC
If you DO NOT want or don't care if, the scent of the soap comes through the film, 75 gauge PVC is the best-looking film and is the easiest to work with. PVC is crinkly, with a beautiful glossy finish. It makes your packages sparkle, which is why PVC is the first choice for gift applications; Spa Kits, gift sets, gift baskets, etc. It's often a good choice for soaps placed in retail outlets other than your own, as it looks great, and typically, will not allow the scent through quickly, if at all.
We often hear complaints about "hard, rough edges" from soapers who are using the pre-made PVC shrink bags. Be advised, that those bags are typically made from 100 gauge PVC...which is way too thick for such a small item as a bar of soap, resulting in those sharp edges. 75 gauge is the recommended thickness for PVC wrapping small items. You'll find it's the best choice for candles as well, in terms of appearance, so if you are wanting the glossy look-and-feel of PVC for your soaps and candles, but still want the scent to come through the film, think about Perforated PVC, the same film, with a film-wide network of tiny pinholes that will allow the scent to come through.
Forgetting for a moment that the scent probably won't come through 75 gauge PVC, this is the best film for protecting bath bombs, fizzies and M&P, as the same properties that tend to keep the scent from coming out, are what protects your moisture sensitive Bombs and Humectant-based soaps from humidity (and rain!) coming in
All that having been said, most soapers DO want the scent to come through, and that where the polyolefins come in.
Polyolefin
Polyolefins are soft shrink films with a feel similar to that of your standard Ziploc-type sandwich bag. There are two processes by which polyolefin is manufactured, the latest of which is a method called cross-linking. Cross-linked polyolefin yields a stronger, more puncture-resistant film than shrink packaging produced by the old method. It's more expensive than standard films and is usually sold under the PREMIUM FILM designation. Polyolefin, an FDA-approved-for-food-contact film is breathable, freezable, microwaveable and allows the scent through the film WHETHER PERFORATED OR NOT.
Most of our soapers use 75 gauge Polyolefin. 75 gauge Polyolefin will allow the scent of your soap through (perforated or not!) and is strong enough for multi-bar packs, soap/dish combinations, and spa and aromatherapy gift sets. We prefer this film for wet M&P bars (especially those with a raised or irregular surface, think: embeds) for three reasons:
- When SHRINKING the film down on an irregular surface, the areas of film that are not in contact with the surface of the soap are more heat sensitive and you are more likely to burn a hole in the film.
- The standard film (no perfs) protects your humectant-based soaps from being as easily affected by the environment (i.e. losing moisture to a dry environment or getting gloopy in a moist one).
- Shrink film gets "stuck" on the wet spots on a bar of soap. It's still wrapped and protected, but there is an "irregularity" in the surface of the film. Thicker film gets stuck less on these wet spots.
We originally perforated many of our film selections for the benefit of our many goat's milk and dairy-based soapers, whose bars need to "breathe" (to avoid rancidity from any dairy components). While these perforations allow the scent through quickly on wrapping...given a day or so, the scent of the soap will still come through the non-perforated polyolefin films as well. Another reason many of our soapers, even those not using milk in their recipe, prefer the perforated films is that the perforations allow any air trapped in your package to escape. Sometimes, without the pinholes, if you perfectly seal a bar of soap, it will trap the air in the package as well...and puff up like a little pillow as you shrink it down. The technique to resolve this minor issue is to squeeze the bar as you handle it normally for shrinking. The air will find a way out, while other than squeezing the bar, you haven't really done anything extra, or taken any extra time.
If you'll be wrapping individual bars only, 60 gauge is the film of choice. (Just to give you some perspective on the film, Apple uses 60 gauge film wrapping iPads). Thinner, easier to cut and seal and quicker to shrink than any of the other films, this film is available in standard, perforated and Soft Shrink varieties. Soft shrink polyolefin is a special formulation that requires less heat to shrink down, a big plus for wrapping butters and other heat sensitive items, and it exerts less force during the shrinking process...so if your decorative bars feature delicate designs, like the petals on a soap rose...or you make shaped soaps, like pie slices, muffins, etc, you might want to opt for this variant of 60 gauge film as it conforms to shapes better than other films.
Within the confines of a shop, or if you ship mail-order, with a little safe handling, you could do much of the above with the thinner, easier to work with (AND easier to blow a hole through if-you-get-careless-with-your-heat-gun, 60 gauge film)...but if you are often moving your product about, like, to fairs, festivals, outdoor sales and the like...the stronger, thicker, 75 gauge film, while it might take a tiny bit of extra effort to cut and seal, and a bit longer to shrink down...will make for stronger packages that will stand up better to the repeated handling during shipping and un/packing..and setting up your racks or displays...and while your customers are doing whatever it is that they do to your bars.
In the same vein, you might want to wrap Multi-Bar packs, gift sets or soap/dish combinations. These would also benefit from the added strength and durability of 75 gauge Polyolefin.
Our recommendation is that M&P soapers do NOT use perforated films if they often sell in very humid or rainy environments as they allow moisture in more easily, and in an arid environment, will enhance the effects of dryness on your bars...but having said that, many of our M&P soapers do use the 60 gauge perforated poly and are happy with it...especially, if you do NOT typically sell your bars outdoors.