Where does UNIFIVE stand on the prevention of silent change of AC adapter parts and used parts?

This page explains our measures against so-called silent change. At UNIFIVE, risk management related to global procurement is thoroughly carried out to counter this.

In recent years, with the globalization of procurement, risks due to silent change of components are emerging, mainly in large companies such as those in the electric machinery industry. There have been accidents reported which were caused by heat generation due to the replacement of resin material used for DC plug parts, from bromine to red phosphorus, the latter of which is a lesser flame retardant. Therefore, we have taken measures to thoroughly manage risks in global procurement.

  * “Silent change” means that the composition of the material will be changed. This may be done by the material manufacturer while the component manufacturer is unaware, for example.


1. Confirmation by acceptance inspection

For all purchased parts (excluding some packing materials), for each lot delivered, according to ANSI / ASQC Standard Z1.4, at the same time as the acceptance inspection, the content inspection of RoHS-specific hazardous substances is carried out with fluorescent x-ray equipment.

Therefore, it is possible to detect the changes that can be identified by appearance inspection or endoscopic examination, as well as the six substances of RoHS regulation.

2. Measures against problems that cannot be detected by acceptance inspection

This issue requires the construction of a relationship of trust which can be extended and confirmed up to the secondary and tertiary manufacturers after the primary manufacturer.

The place where silent change is done is not the place from which final products are actually delivered. The change of composition of the raw material is the main culprit. So, we have established a relationship of trust which can be confirmed with secondary and tertiary manufacturers, with whom it is normally difficult transparently do businesses with.

3. Flame retardants in plastics and issues caused

NITE, National Institute of Technology and Evaluation, (an independent administrative institution) disclosed information on flame retardants in plastics and issues due to flame retardants in 2014, but we also focused on the same problem at the same time. We have independently investigated the flame retardants of PBT resin (polybutylene phthalate) used for insulating the sleeve of plug parts. At the request of a customer, we visited the site of a secondary manufacturer and a third manufacturer, and confirmed the materials’ composition and tried to prevent silent change.

Subdivision of description in specification

Regarding matters in which red phosphorus is mixed in the flame retardants of plastics resin which we have heard frequently about in the market in recent years, the material should not be intentionally mixed with red phosphorus. If the product contains red phosphorus, we will diligently assess the product through a warranty card.

4. Contamination of red phosphorus

Regarding matters in which red phosphorus is mixed in the flame retardant of plastics resin which we hear frequently in the market in recent years, it is not intentionally mixed with red phosphorus in the material, and even if it contains it, We are submitting it in the form of a "warranty card".

4M – Thoroughly communicate change

We exchange contracts for 4M (material, methods, machine or man) change to all manufacturers, and changes in any of these areas require approval beforehand. Currently, all the manufacturers which we deal with have a contract concerning 4M change and we will not conduct trading for any reason if we cannot make such a contract.

As globalization of procurement progresses, we are promoting further risk management and supply chain management with manufacturers, and building relationships of trust.

You can get the product catalog in PDF.

Product initiatives

Since 1989, UNIFIVE has maintained the quality of their AC power adapters and switching power supplies through rigorous quality controls.

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