Is it waterproof?
Stickers and labels can be made of a variety of materials to give you a “Waterproof Sticker” but the question you should be asking yourself is how much water protection do I need? And, how long does it need to last? Why pay for top of the line waterproof protection if your product is only meant to last a few months. On the flip side you do not want to short change yourself if you have a product that is meant to withstand an outdoor environment for many years.
How do you evaluate the numerous materials, adhesives and printing process available to determine what is right for you?
Where do you begin?
As with most label jobs, it all starts with a few questions like:
- Is the adhesive waterproof enough for my application?
- What are the inks characteristics ?
- What kind of based material should I use?
Additional questions that should be asked are:
- Besides water, are there other environmental concerns that the label needs to withstand? (i.e. abrasion, chemical contact or temperature extremes)
- What is the sticker sticking to?
- How long does your waterproof sticker need to last?
There are a couple of standard choices available and are usually either Acrylic based adhesive or Rubber based adhesive. The basic characteristics of each are:
Rubber Based – Rubber based adhesives bond quickly to a wide range of materials and surfaces. It is normally less expensive, but not a good choice for long term waterproof stickers because it has a tendency to break down over time when exposed to sun, rain and temperature fluctuations. Stickers made with rubber based adhesive are great for indoor products with a short shelf life.
Acrylic – Acrylic adhesive does not bond as quickly as rubber based adhesives, but gives a more permanent bond. Acrylics are resistant to long term UV (sun) exposure and have a better temperature range. For a truly waterproof sticker, acrylic adhesives should be your first choice.
Today there are more choices in printing methods than ever before and with each new kind of technology there are new ink formulations. When considering how well your sticker will hold up over time, you need to know what type of ink is being used.
Some of the inks and technologies being used include:
- Water based inks – Water based inks are used in many printing methods, from old fashioned flexographic printing to the new industrial ink jet. Water based inks are inexpensive and can produce very beautiful detailed graphics but should not be used for outdoor weatherproof stickers.
- Solvent based inks – As the name implies, solvent based ink uses solvents to suspend color pigment. Once printed, the solvent evaporates and leaves a very durable print. This type of printing is great for outdoor weatherability; as for the environment not so much.
- UV inks – When exposed to a high intensity light, UV inks are cured and bond to the surface to produce a very durable and UV stable waterproof sticker.
There are an array of materials used to make stickers, but which to use depends on the intended purpose of the label. Some of the materials for consideration are:
Paper – You may not consider paper as being waterproof, but add a laminate or varnish over the print and it can become very water resistant. This is a very inexpensive way of protecting a labels from a fair amount of water damage for a short period of time.
Polyolefin – Polypropylene and Polyethylene sticker materials are good all-around waterproof materials as long as they are intended for use on indoor products with a less than 2 year shelf life.
Polyester & Vinyl – For true outdoor weatherproof stickers, there is nothing like polyester or vinyl. These materials can take the abuse of chemicals, heat, cold, and even a moderate amount of UV exposure. By adding a clear anti-UV polyester laminate, we have seen labels last more then a decade outdoors in direct sunlight.
Bottom line is “weatherproof stickers” can mean different things to different people. Make sure you know what kind of environment the sticker will see and for how long.
If in doubt give us a call.