Il giorno 19 settembre 2012 è stata pubblicata sulla Gazzetta Ufficiale dell’Unione Europea la variazione del regolamento REACH riguardante il contenuto di Piombo negli oggetti di “gioielleria” (“jewellery” nella versione inglese della norma, “bijouterie” nella versione francese), dove per gioielleria si intende:
- braccialetti, collane e anelli
- articoli di gioielleria per piercing
- orologi da polso e bracciali da uomo
- spille e gemelli per polsini
La legge è estesa sia ad oggetti di gioielleria che di bigiotteria, ad uso sia per adulti che per bambini, sono esclusi dalla legge oggetti come portachiavi e monete; il testo della pubblicazione è riportato nell’Allegato 1 del presente riepilogo.
In seguito alla consultazione e studio delle commissioni incaricate per la valutazione e competenti in materia, cioè il Risk Assessment Committee (RAC), e la Committee for Socio Economic Analysis (SEAC), è stato deciso che sarà da considerarsi il contenuto di Piombo in proporzione percentuale al peso di ogni singolo componente dell’oggetto di gioielleria, non essendo disponibile un metodo che mimi in maniera soddisfacente il rilascio di Piombo da un oggetto sottoposto a suzione.
Nella fattispecie, è stato deciso che il contenuto di Piombo non dovrà essere superiore allo 0,05% in peso (ovvero 500 ppm), riferendosi al peso di Piombo in proporzione al peso del singolo componente dell’oggetto – dove per “singolo componente” si intende ogni materiale che costituisce l’oggetto, nonché ogni parte accessibile dell’oggetto.
Poiché questa norma entrerà in vigore a 20 giorni dalla sua emissione e cioè il 9 Ottobre 2012, rientrano in deroga al limite tutti gli oggetti messi in commercio per la prima volta antecedentemente al 9 Ottobre 2013 e tutti gli oggetti fabbricati prima del 10 Dicembre 1961.
On August 14, 2008 was approved in the United States the Consumer Product Safety Improvement Act – CPSIA, in order to introduce the new provisions on product safety for children. Section 101 of the Act introduces new limits on both the quantity of lead in baby
products and paints used in these products (considering “Products for children” the goods intended for children aged between 0 and 12 years). The act provides as well that, staring from exact dates mentioned on the Act, can not be imported into the U.S. baby products containing amounts of lead exceeding the limits set by law; going into the details, was regulated that:
- from August 14, 2009, the limit was increased to 300 ppm;
- from August 14, 2011 the limit will drop to 100 ppm
Really important are the dispositions regarding the permitted limits of lead in the paint used in products for children: it is strictly avoid to import products with coating (paint, lacquer, enamel) containing a quantity of lead exceeding 90 ppm (new limit replacing the previous 6% of the total weight of the coating – 600 ppm).
The state of California has also extended these parameters to both fashion accessories and jewelry/custom jewelry for adults.
(For further information: www.cpsc.gov)
In recent years, due to both the leather tanning processes (short time of processing and drying, semi-finished products from abroad, etc.) and the particular climatic and environmental situations in some countries (especially Asia) there has been a sharp increase in the reporting of early abnormal oxidation problems on metal accessories.
This happened on all types of plating processes, both the processes that provide good thickness of precious metal and the processes with coated material. With reference to the above mentioned reasons and taking as examples the applications on aerospace field, we
decided to apply a new type of nickel called Nickel Phosphor that immediately gave good results.
From all the carried out tests with base material Zama, Brass and directly using precious metal on nickel or with anti-allergic finish (with white bronze on Nichel), it follows that the use of Nickel Phosphor as an intermediate layer (from 1 to 3 my), significantly increases the corrosion resistance of the accessories.
This resistance, with a precious metal thickness of about 0,20 my, is comparable (and sometimes better) in some tests (especially in moist heat), to samples made with standard nickel and with precious metal having a thickness of around 0,30 my.
The most striking feature is that in humid heat, we do not have the usual green salt deposits, typical features of normal nickel plating that we normally have with precious metals under 0,5 my.
These salts, although after the washing process let the object apparently intact, can give some micro porosity in the galvanization, weakening the sample with respect to the corrosion. Moreover, this process is regularly used since almost three years with an excellent feedback even into the real life, so that many fashion houses have seen a decreasing in the number of
sent beck imperfect articles.
These problems have recently assumed alarming extent especially considering the significant increase in both sales in the Chinese market and production of components of fashion by companies located in China on behalf of foreign companies.
A thorough review on the state of air pollution in major cities in China (thanks to numerous reports and publications available in various web sites) showed that the in the air of most Chinese cities there are the same pollutants that are in Western Countries, but in much greater quantities.
The attention has been immediately focused on nitrogen oxides Nox; their presence in the air in large quantities is mainly due to wild industrialization through which the Country has been subject over the past 15 years. .Extensive studies on the effects of acidification have showed that between SO2 and Nox there is a ratio of at least 5 to 1, meaning that a concentration of NOx equal to 20% of the concentration of SO2 is enough to have the same effect of acidification. The simultaneous presence of high concentrations of SO2 and NOx in the Chinese atmosphere, together with large amounts of fine particles having humidity levels close to the limits (with the consequent effect of thermic inversion), let the level of aggressiveness of the air be definitely greater compared with level normally found in the developed countries. It’s also really important do not underestimate the environment’s micro-climate into which the accessories are used; this parameter is another negative factor that goes to add up all the others. This information has enabled us to immediately guess that the normal control procedures at today valid to guarantee the quality of metal accessories were inadequate and that it was necessary to develop new accelerated corrosion tests able to represent the Chinese Atmosphere.
Considering as valid tests the tests today used and working to let them be more aggressive, (especially on the level of exposure times), it was theorized and developed a new type of test (which we call ‘TEST CHINA’) based on what is reported on paragraph 7 of the UNI ISO 4524 second part.
The test requires that the objects are exposed to natural temperature for 2 hours on a suitable test chamber containing nitric acid; such a test has an official value and is representative with regard to the aggressiveness of NOx in the atmosphere environment.
The above mentioned test on a large number of accessories, made with different base metals and treated by a galvanic process with different finishes, led to the following considerations: The surface treatment by the NOx causes a chemical attack on the surface layer which, if is not adequate, can also attack the underlying layers until to reach the base metal, with devastating consequences for the objects, especially if the base metal has some microporosity. We can say that the use of brass is much better than the use of alloy or iron. The performance of a mechanical brushing on a metal base has a beneficial effect on the closure of surface micro-porosity. The mechanical brushing create an action of removal and causes a significant warming over the surface of the base metal with a brazing effect on the micro holes. Should not the objects have a mirror effect, is much better to make the mechanical treatments on the base material rather than on the galvanic, as normally occurs.