本文へ移動

Wisdom For Polyethylene

Measurement of particulates in liquids

2024-10-15
Measurement of particulates in liquids

How to identify additives adhering to the bag

 

It is important to know how to check additives that are powders adhering to the bag.

Most additives are not water soluble. The bag is filled with water and the additive adhering to the inner surface of the bag is mixed into the water, which is then measured with a liquid particle counter to make a determination.

This method is used in the incoming inspection of plastic bags, particularly by pharmaceutical manufacturers. In the past, we have measured several million particles (between 2 µm and 40 µm) on the entire inner surface of normal LLDPE bags.

Therefore, when cucumbers, Chinese cabbage, etc. are pickled in plastic bags together with ‘asazuke-no-moto'(seasoning for easy-to-use), which is often advertised on TV, the above-mentioned fine particles adhere to the pickles. Even if the vegetables have been grown organically and without pesticides, the result is that they are definitely contaminated during the cooking process.

A confirmation method that can be experimented in your company (especially for anti-static types).

If you fill a plastic bag with tap water, shake it and leave it for a few minutes so that air bubbles would be disappear. Then check the water in the bag under a fluorescent light, you can easily see sparkling reflective substances.

In the case of anti-static types, foaming may also be observed.

 

Finally, other typical additives include,

‘Ultraviolet absorbers (polyethylene bags that reduce the transmission of ultraviolet rays)’

Anti-corrosion agents (plastic bags for packaging metal machinery and parts).

Anti-fogging agents (plastic bags for packaging vegetables, etc., which prevent water droplets from forming on the inner surface of the bag).

Antimicrobial agents (silver zeolite or organic antimicrobial agents kneaded into the bag to create an antimicrobial effect).

Basically, any additive can be kneaded into the bag, and as long as it is heat resistant, it can be produced, so there is a possibility that a wide variety of additives will be kneaded into the bag in the future.

However, while organic types can be used, the adverse effects of the above-mentioned bleed-out must also be taken into consideration.

※PAY ATTENTION
Unfortunately, we cannot answer any telephone inquiries.
If you have any questions, please contact us through the website and we will reply to your inquiry by e-mail.
Thank you for your understanding.
 
TOPへ戻る