Number

015-EN

Section

General Section

Use

Abstract

Danish furniture manufacturers use lacquers that cure by means of ultraviolet radiation as the most frequent surface treatment of wooden furniture. A shift towards monomers and acrylates with a higher molecular weight means that the acute toxicity of the UV lacquers is reduced. The monomer and binder replacements could be performed without considerable technical or financial consequences for the varnish manufacturer as well as for the end user.

Substituted substances

Alternative Substances

Reliability of information

Internet information: data are from an internet document and only a basic and partial evaluation could be performed

Reason substitution

physical hazards

Hazard Assessment

Substance to be substituted: 1,6-Hexanediol diacrylate fulfils the criteria to be listed in the Substance Database according to SUBSPORTplus Screening Criteria (SDSC). It may cause an allergic skin reaction, according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). Alternative substances: (1-methyl-1,2-ethanediyl)bis[oxy(methyl-2,1-ethanediyl)]diacrylate may cause allergy or asthma symptoms or breathing difficulties if inhaled, according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). Oxybis(methyl-2,1-ethanediyl) diacrylate is not listed in the SUBSPORTplus Database and has no harmonised classification according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation) » Check the Substance Database according to SUBSPORTplus Screening Criteria (SDSC)

Description of Substitution

Danish furniture manufacturers use lacquers that cure by means of ultraviolet radiation as the most frequent surface treatment of wooden furniture. UV curing primers and finishes are being applied by rollers or by spray guns, and are subsequently cured in special ovens with UV light. When UV cured lacquers are applied, the part of the lacquer having the lowest viscosity will penetrate into the wood and become inaccessible to UV radiation, thus remain uncured. Additionally, the lacquer may contain monomers and binders that do not completely polymerise. In this way, all these uncured components may fairly easily emit from wood and lacquer when the furniture is installed at the end user’s and will deteriorate the indoor climate. The project this report refers to has shown that UV curing furniture lacquers contain more or less unreacted monomers after UV curing. However, the varnish manufacturer can reduce such emissions by careful selection of appropriate materials. The selection can be made by a thorough study of the environmental properties of the ingredients. The study should focus on monomer and binder, since they are the most important components. Monomers’ and binders’ content of chemical compounds were reflected by their statutory safety data sheet and were given an indication regarding their reactivity: lower reactivity leads to more unreacted compounds in the varnish and thus results in higher diffusion. There were significant differences between raw materials’ tendencies towards diffusion after UV curing. For example, the chemical analysis showed that the lacquer manufacturer simply by changing his commercially used monomer HDDA to DPGDA (Dipropylene diacrylate - CAS 57472-68-1) or TPGDA (Tripropyleneglycol diacrylate - CAS 42978-66-5) could reduce emissions significantly. A shift from HDDA to TPGDA at the same time means a change to acrylates with a higher molecular weight, and thereby to less acute toxic acrylates. A change in primer - acrylates with much higher molecular weight at the same time means that the acute toxicity of the UV lacquers is reduced. Even though the final formulation of the UV lacquers was not available when this project ended, all results indicate that the new formulations consist of more pure raw materials, i.e. fewer constituents in the final product. This must be regarded as an advantage, as there is not exhaustive knowledge about health and environmental properties of the different constituents. The monomer and binder replacements could be performed without considerable technical or financial consequences for the varnish manufacturer as well as for the end user. The optimisation of monomer and binder in the lacquers will lead to less diffusion of monomers from lacquered wooden furniture, and thereby help improve indoor environments. Acrylates in general are regarded as causing sensitisation. Substitution by other acrylates does therefore not remove this risk.

Case/substitution evaluation

One of the alternative substances (CAS 42978-66-5) does not pass the eliminatory criteria set by SUBSPORT, therefore we recommend further search for safer alternatives. The case story is in the database despite this, due to the fact, that the workers are well protected during the application and therefore are not exposed to the substance. Moreover, the alternative releases less uncured components as compared to the substituted substances. Some acrylates are embryotoxic.

State of implementation

Pilot study

Date and place of implementation

21-12-2010, Denmark

Enterprise using the alternative

https://www.teknos.com/industrial-coatings/

Type of information supplier

Authority

Further information

http://www2.mst.dk/udgiv/publikationer/2010/978-87-92708-78-6/pdf/978-87-92708-79-3.pdf

Type of publication and availability

Freely available at www.mst.dk

Publication source

Type of publication and availability

http://www2.mst.dk/udgiv/publikationer/2010/978-87-92708-78-6/pdf/978-87-92708-79-3.pdf

Date, reviewed

December 11, 2020