When transporting and storing electrical components and final products from stores, users need to know the correct bag to use so the entire process is completed as safe as possible. It’s important to adopt the usage of a bag during transportation as this minimises the risk of static electricity affecting the products.
Most people know about static energy and the effect it can have. You get a brief shock on a metal door handle by scuffing your shoe on the carpet for example. Also, you’ve heard about when drying clothes in a dryer, it will produce a static cling. Doesn’t really seem like that much of a problem though does it? In the context of static encountering electrical circuits and devices… it can disturb and in worst cases destroy them.
Protective bags first came into use back In the 60’s with the first batch called the ‘pink polly’ bags and in the 1970’s static shielding bags were introduced at the latter part of the decade.
There are 3 main types of static threats which electrical components should be protected from:
Direct Discharge (ESD): A direct discharge to the bag can make the component inside melt or fuse the circuit due to it being subjected to a high current
Static Fields: Fields can introduce devastating currents in circuit conductors. It can also break down the circuit dielectric
Tribocharging: Sometimes there can be friction between the bag and device which can produce static voltage and fields that damages the component
Type of bags
Pink Poly Bags
This bag can dissipate a static shock to the ground. This keeps static electricity from building up in the component. The material is antistatic so it will not tribocharge when rubbed against other materials.
These bags have no shielding ability which is drawback. If a static charge happens outside the bag, the electronics will have no protection as the static field or discharge will penetrate the bag.
Construction of Pink Poly Bags
They’re made from plastic that’s loaded or surface coated with a chemical antistat. The pink colorant is used to differentiate this type of bag from non static controlled materials.
Pink poly bags are great for electrical items that have no static susceptibility. The main purpose for these bags are for protecting or package support material that is close to static sensitive devices.
Black Conductive Poly Bags
Black Poly are very conductive bags which can dissipate a charge at a fast rate. The flaw of this means that a static object or person can spark ESD to the surface. The main aim of static control is to swap charges at a slow enough rate to avoid sparks which initiate ESD.
The material is conductive so does produce a light layer of protection but the bag isn’t dielectric which means there’s no plastic layer inside to isolate the component inside.
Construction of Black Poly Bags
These bags are made from plastic that is volume loaded with a conductive carbon. The appearance is black.
In times past these types of bags were used as an alternative to pink poly and shield bags as they were a lower cost and had some shielding compared to pink. Shielding bags cost has lowered so the demand for black poly bags is likely to diminish as the bags are opaque which means the contents must be removed for identification that creates a new problem for static damage.
Like a poly bag, shield bags provide a dissipative and antistatic protection but with the added attribute of a metal shield and polyester dielectric so static doesn’t enter the bag and damage the component.
These types of bags will stop a very high percentage of a 1000 colt static pulse applied to the outside of the bag from reaching the component inside.
Shielding bags consist of several layers. These layers are dissipative poly glued to metalized polyester. The outside layer of polyester is coated in an antistatic coating.
These bags can be used for the vast majority of electrical components and products.
Moisture Barrier Bags
Moisture barrier bags provide a variety of safety measures like dissipation, antistatic properties, static shielding and adds a moisture vapour barrier.
This is one of the strongest bags on the market, being significantly stronger than a shield bag. Similar to the shield bag in terms of structure. There’s two types of moisture barrier bags ‘foil and tyvelk’ and heavy metallization.’
This bag is adopted when barrier protection or maximum shielding is required. Surface mount devices are carried in moisture carrier bags to avoid moisture absorption by the IC case material.
Box Build – Final Product packaging
European Circuits also offers final product packaging. This means the product is effectively ready to go in to the marketplace once it leaves our facility.
If you have any questions please get in touch and keep up to date on our blog for everything else.