SMART TECH BAGS® TECHNOLOGY
Laddawn-made products are engineered to provide greater confidence in use and more flexibility to balance strength, gauge, and cost. For medium and larger applications where strength is paramount, these items are engineered to provide three times the impact (ASTM D1709) and twice the tensile strength (ASTM D882) of conventional low density film. Look for the Smart Tech Bags designation on all Laddawn-made products for standard, antistatic, low-temperature, UV-resistant and postal applications.
Need to customize your packaging solution? Here's what you should know about other options for materials and additives:
Blocking is the term used to describe what happens when polyethylene film sticks together. Anti-block is an additive that roughens the surface of film at a microscopic level. This makes it easier for layers of film to separate. Anti-block makes bags easier to open, too.
For static sensitive applications – like packaging for electronic parts or for static sensitive automated packaging or mailing equipment – anti-static additives lower surface resistivity and static decay times. All Laddawn anti-static additives are amine-free: that means they work better in lower relative humidity, and won't corrode polycarbonate surfaces.
Note: To meet the full static decay and surface resistivity requirements of MIL-PRF-81705D Type II Class 1 and EIA-541, films must be 4 mil or greater and formulated with 6% or more Laddawn anti-static additive. All Mil Spec anti-static films must be manufactured with low density (LDPE) resin. Linear low density (LLDPE) resin is extruded at higher temperatures which may cause a loss of anti-static performance.
HIGH DENSITY POLYETHYLENE
The chemical structure of high density polyethylene (HDPE) lends itself to greater toughness – roughly twice the tear and puncture strength and better chemical resistance than low density polyethylene (LDPE) and linear low density polyethylene (LLDPE). On the downside, HDPE film is less flexible and less clear than its LDPE and LLDPE cousins.
LOW DENSITY POLYETHYLENE
Low density polyethylene (LDPE) is a popular choice for a wide range of light-weight packaging needs. LDPE provides moderate strength and good clarity for general purpose applications. A commonly used type of LDPE is actually called Clarity.
For smaller bag, film and tubing applications, where higher transparency is more important than product strength, items are formulated with a type of low density polyethylene (LDPE) resin called Clarity.
LINEAR LOW DENSITY POLYETHYLENE
When film strength is more important than clarity, linear low density polyethylene (LLDPE) is often the right choice. LLDPE provides better tear and puncture resistance for larger capacities or bulky objects. Two great options for LLDPE are Hexene and Octene.
Hexene is a very strong linear low density polyethylene (LLDPE) that stands up to more rigorous demands. Hexene is the most common choice where added strength is important.
Octene is the strongest linear low density polyethylene (LLDPE). For a few pennies more per pound, Octene delivers the highest tear and puncture strength of any LLDPE material.
There's really only one component in most low or linear low density polyethylene bags, film or tubing formulations that can be at all scratchy: anti-block. Anti-block additives work by making the surface of the film rougher. Non-scratch bags, film and tubing contain no anti-block additives and therefor provide smoother film surfaces.
Metallocene's prime benefit is its ability to make film more resilient. Metallocene may not improve the force needed to tear a film, but it will allow it to stretch more under force and seal better. Even at lower temperatures, items formulated with metallocene don't become brittle. That's why metallocene is the choice for freezer or ice bags.
Polypropylene (PP) is the choice when clarity is paramount. Polypropylene offers about five times the clarity (one-fifth the haze values) of Clarity low density polyethylene. Polypropylene is a common choice when packaging for display.
These items are formulated to comply with the USPS T-3204 protocol for use on automation rate flat-size mail pieces. Performance standards met include haze, blocking, coefficient of friction and static charge decay.
Slip additives decrease the coefficient of friction (increase the slipperiness) of the surface of a bag, film or tubing. Standard formulations have enough slip additive to keep bags, film or tubing from sticking together but not so much as to make them difficult to handle.
Some users require increases in slip additive to increase the degree to which their bags, film or tubing glide in a handling or packaging process.
Some users require low slip bags, film or tubing to decrease the likelihood of their product sliding when packaged. Mattress bags are a good example. Low slip bags are formulated with no slip additive.
Direct sunlight (UV light) causes unprotected film to discolor or become brittle. UVI/UVA (ultraviolet light inhibitor / ultraviolet light absorber) protects both the film and its contents from the damaging effects of the sun and inhibits thermal degradation of the film. Do not use UVI/UVA additive for film that may come in contact with agricultural chemicals or pesticides as they may reduce the product's efficacy.
Packaged metal items can corrode during storage or shipment if exposed to oxygen, water and other contaminants. A Vapor Corrosion Inhibitor (VCI) is a film additive that has enough vapor pressure under normal circumstances to become a gas. VCI fills the interior of a sealed bag with molecules that adsorb onto the surface of a metal item to form a microscopic, protective barrier.
Note: All VCI film, bags and tubing must be formulated with low density (LDPE) resin. Linear low density (LLDPE) resin is extruded at higher temperatures which may reduce the concentration of VCI in the final product.