Notizie CATAS n.3 2012

QUARTERLY NEWS EDITED BY CATAS YEAR 17 / N. 02 JUNE 2012PERIODICO D’INFORMAZIONE EDITO DAL CATAS ANNO 17 / N. 03 SETTEMBRE 2012

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Management, Editing and AdministrationCATAS spaVia Antica, 24/333048 San Giovanni al NatisoneUdine / ItalyTel. 0432 747211Fax 0432 747250www.catas.com

PresidentMichele Bressan

Managing DirectorAndrea Giavon

Coordination CATAS NewsFranco BulianFranco PreteLuca Bertossi

Design Deeper ComunicationUdine / Italy

Layout and graphics Maurizio MarussiAnnamaria Franz

Reproduction or duplication of the contents of this quarterly on any support is authorized under condition that the source - © CATAS - San Giovanni al Natisone - Udine - Italy is being cited All rights reserved

03in this issue

04 The cultural value of furniture05 The activity of the environment section of

CATAS is growing06 Legionellaire’s disease: the risk should not

be underestimated 08 Supplies of upholstered furniture for the

shipping sector10 Surface cracking of coated MDF panels14 The book “Materials and technologies of

the Furniture industry“ has been translated15 Coating systems for exterior wood.

Searching for a “very” accelerated test method

21 Study of stress on a plate wall brackets32 Wood flooring on heated screeds, what

is their contribution in terms of thermal insulation

33 New disciplinary and Manual for the control and the correct use of cork caps

34 GET INSPIRED BY MATERIALS36 Publications

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidianaAndrea GiavonThe cultural value of furniture

Several times on these pages of Notizie CATAS I thought about this subject and tried to stimulate a di-scussion on the “culture” value of furniture. It is certainly not my discovery, there is a huge story to prove it, but many times we forget this because perhaps taken for granted, especially in countries where it was well developed as it is in Italy.This attitude, to give many things for granted, the Colosseum, Venice, Florence et al, is typically of Italy (the BelPaese), it sharpens up to worrying levels in strange times and of great changes such as the one we are experiencing. As repeated in other articles, it is not my intention to make historical - economic asses-sments, but just think of an industry that in my opinion and also other high values.Ever since I started this journey in the world of furniture, from all parts of the world and from many of its inhabitants I have heard the usual adage (or chorus) that “Italy is the homeland of design”. These words seem easy and simple, and so frequently used and has become the common heritage, so take it for granted (is once again this attitude!). But even if we stop for a moment and try to analyze the non-trivial semantics of words and their interconnectedness, we realize that is not unique the concept of “design” (ndr: at least in italian language). It is even less obvious what is meant by using the word homeland in this context. Most likely the author of the phrase meant that the style (shape of forms) of both form and color is a feature of many industrial sectors of our country, including furniture.In an era of osmosis between languages, the word design (similar but not equivalent to drawing) has pla-yed well this “semantics function “ but soon its genesis got lost and / or forgotten.The furniture industry I met thirty years ago had very clear the overall thickness of culture and technology that led to the birth of a product, today it does not seems the same. And this was a common consciousness, whether it was a desk, an office chair or a domestic chair. Obviously, those constituent elements reflected the culture of that time.In fact many products for the human being have been produced and many of these have become exam-ples, history, “ pieces of design “ (as defined by someone) even museum pieces. It does not matter the terms, what really matters is that the cultural elements found designers and companies willing to take the risk. I feel lucky to have met these stimulating realities. Within this “cultural fabric”, CATAS, with standards, testing, technical information, were part and acted as a constitutive element of a reality in motion, starting from pioneering visions (talking about quality in difficult times) to become what is today. I do not know and I do not yet understand why at some point what was called design, slowed down and this was noticeble. Everything has changed and sometimes very quickly (structure of companies, markets, relationships, etc.) and some other features have been added as needs to which also the furniture world shall answer. Furniture is a consumer product that has a very close relationship with the people, physical, emotional, intellectual, and therefore also cultural. All these features and their decoding process in a project (design finally!) Is a characteristic feature of Italian culture, perhaps sometimes badly treated or buried or hidden for various reasons, also because of an economic crisis too long lasting. The consumer has grown with its needs in recent years and those who were avant-garde positions are now heritage of all, I am referring to environmental issues in their broadest and real sense to those of our future such as sustainability, to the important aspects related to the concepts of products and furniture for all. These are now topics that we encounter on a daily basis and thus must necessarily become the design features of Italian furniture from the partition wall to the chair for the tavern. The effort that lies ahead is great but the potential and techni-cal tools are there; CATAS as always at the forefront. What is missing is perhaps a greater confidence on the part of the companies in their own ability and by the estabilshment in companies with perhaps some practical, real and agile tangible action. And the times of tears, recriminations and proclamations are over, we shall start to do something that we were used to do well in the past, furniture design.

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Sara ZanchielloGli appartamenti - palestra

Staff CATAS

The activity of the environment section of CATAS is growing

The mission of CATAS towards the activities that support companies on environmental issues has always been one of the peculiarities of the Institute.The indoor pollution problems, first of all the formaldehyde emission from wood based panels, have always been followed at all levels by CATAS technicians, providing con-sequently different services (con-sultancy, testing and certification) in line with the regulations and market demands.Recently, the activities in the envi-ronmental field have been further developed and strengthened not only as regards the tests carried out (VOC, CARB certification, etc.) but also developing other types of ser-vices such as the studies on the life cycle assessment (LCA) and espe-

cially with the analysis of the end-of-pipe emissions and on those refer-ring to the safety in workplaces.The environment section of CATAS, active since 2009, is able to support companies in the fulfilment of all the measures concerning the envi-ronment from air emissions, safety in the workplace and others. CATAS provides advice in the preparation of applications for authorization to air emissions as regards the instal-lation of new plants and renewal of existing authorizations.The laboratory is also structured to provide support from the analytical point of view in the initial screening of airborne pollutants in the input and output generated by the plant for future installation.To comply with the existing regula-tions regarding safety in the workpla-

ce, CATAS provides an assessment of the chemical and biological risk in the workplace from both the in-strumental point of view and docu-ments.In these three years the environment section of CATAS has experienced a remarkable growth of its activity. This growth, which has also led to the employment of new technicians, is certainly connected also to the high-level skills and instruments available at the chemical department. This growth is thereby bringing CATAS be considered as a reference point for its specificity, skills, knowledge and, last but not least, because of its centrality with respect to the official institutions on these issues.

References:Formaldehyde: [email protected], [email protected] substances in furniture: [email protected], [email protected]: [email protected] Consulting (MUD SISTRI, etc.): [email protected] emissions and working places: [email protected], [email protected], [email protected]

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidianaLorena Riul

Legionnaire’s disease: the risk should not be underestimated

The advice to take appropriate preventive measures

Legionnaire’s disease infections are presently an increasingly serious problem and concern. A con-firmation of such situation derives from the increase of pulmonary infection cases recorded in recent ti-mes, both in Italy and abroad. Legionnaire’s disease is a severe form of pneumonia caused by a bacte-rium that grows in natural water plots but it finds optimal conditions for its proliferation in plumbing, air conditioning, irrigation, swimming pools, sau-

nas, ornamental fountains and even dental instru-ments. In particular, water systems with stagnation or presence of scaling, centralized heating systems with extensive networks of pipelines and in general all situations in which water temperature is constant in the range between 25 and 45 ° C (optimal for the bacterium growth) are areas with a high risk of co-lonization by the Legionnaire’s disease bacterium. Very often the tourist facilities or spa’s, nursing ho-mes, hospitals are the environments in which, more than others, this situation occurs and therefore are better controlled also for the type of people who at-tend them.

Legionnaire’s disease infection strikes through in-halation of contaminated water droplets, spread in the form of aerosols (1-5 microns) that causes, especially to people at risk, serious respiratory pro-blems. The Legionnaires’ Disease Surveillance Net-work (ELDSNet) and the National Institute of Health (ISS) are subjected to special surveillance of these infections considering an emerging problem in pu-blic health with important economic drawbacks.

In Italy a total of 1,234 cases of Legionnaire’s disea-se were reported by the ISS in 2010. The incidence of the disease is, as in previous years, significantly higher in the Northern regions (31.2 cases / 1 mil-lion inhabitants) than those in the South (6 cases / 1 million inhabitants), while the value of the centre of Italy is close to the European average (20.6 cases / 1 million inhabitants).

In different regions of Italy, particularly in those with a strong presence of tourist resorts, there are gui-delines for controls on the safety and proper mana-gement of water for tourist-receptive organizations and spas.Proper prevention through adequate treatment and management of water systems are essential to re-duce the contamination of organic agriculture.This subject is particularly sensitive to CATAS that, in addition to being involved in activities and initia-tives through meetings and information dissemina-tion, performs sampling, monitoring and analysis in accordance with the guidelines issued by the Per-manent Conference for relations between the State, Regions and Autonomous Provinces of Trento and Bolzano (Provision 13.1.2005 containing the Guide-lines markings information on Legionnaire’s disease

for managers of tourist facilities and spa; Document 4th April 2000 with the Guidelines for the Prevention and control of l Legionnaire’s disease and the Euro-pean Guidelines fro Control and Prevention of Tra-vel Associated Legionnaires ‘Diseaase dell’EWGLI, which also contains the procedures for international

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Lorena Riul

surveillance of cases of legionnaires’ disease asso-ciated with travels).

Preventive measures for risk reduction

In large buildings, as well as in small rooms (apartments, dental studios, etc.). Periodic main-tenance contributes effectively to prevent the co-lonization of plants by the Legionnaire’s disease bacterium and especially to limit its proliferation and dissemination.The risk analysis is important in order to consider the source of water supply system and the possible contamination areas within the same building, the

wrong operating conditions, but reasonably fore-seeable, the intakes’ air for buildings should not be located near the discharge of cooling towers.It is also advisable to regularly cleaning and disin-fection of the filters of air conditioners, the decalci-fication of the aerator taps and showers systems, replacing the seals and other worn parts, emptying, cleaning and disinfection of storage tanks’ water.For apartments or accommodation in seasonal operation, before the reopening is appropriate to make a thorough cleaning of the tanks, mixers and showers. It is also advisable to drain along the wa-ter from all taps.

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidianaFranco Prete

Supplies of upholstered furniture for the shipping sector

Despite the recent disaster of the Costa Concordia and “misfortunes”, fortunately less serious, that happe-ned to other ships around the world, cruises draw an increasing number

of people, attracted by the sights and fascinated by these magnificent floating cities.But the seas are not only crossed by cruise ships, just think of the spread of the ferry boats, hydrofoils, pleasu-re boats of small and medium cabo-tage, cargo ships.Safety in the midst of the seas and oceans is therefore an essential re-quirement for both humans and the environment, which requires the adoption of strict preventive mea-sures that can only be transnational. In fact, such prescrptions have long been implemented and regulated at both European and international le-vel:- Directive 96/98/EC was issued “Marine equipment” (as amended by Directive 2008/67/CE) for ships flying the flag of a Country outside the European Union;- several international conventions, including the Safety Of Life At Sea (SOLAS), are in force for ships flying the flag outside European Union Countries.

Just because the wearing of rescue at sea is complex and not always im-mediate, especially offshore, among other provisions to ensure the safety

of passengers and crew, the fire pre-vention plays an important role since fire can cause events with dramatic consequences.

Among the numerous regulated pro-ducts, in this article we take care of upholstered furniture and, in parti-cular, of seatings; we will examine what are the requirements for such products.

International contextThe rules are set by the IMO (Inter-national Maritime Organization) that is a ONU specialized agency whose membership includes 169 Countri-es.Among the many conventions adop-ted, the current (since 1980 although updated different times), is known as SOLAS 1974. It is curious to note that the first document dealing with

these issues dates back to 1914, as a result of the strong emotion for the sinking of the Titanic two years be-fore.The late update is just the fire reac-tion tests of products that are esta-blished in the FTP Code 2010 (Fire Test Procedures) whose new revi-sion came into force on the 1st July 2012, replacing the 1996 edition.For upholstered seatings (Annex 1 - Part 8) the “burning cigarette test” and the “flame ignition source test” are required. They are both per-formed by CATAS, which have not changed substantially over the pre-vious edition (Resolution A.652 (16) of 1989).We always carry out the tests on specimens derived from the compo-site or composites “cover-interliner-filling” used in upholstered seatings but with something new as it is not possible to carry out the tests on composite/s if you can demonstrate that:1) the cover chosen has already been tested on a non-flame-retar-dant filling material (ie, the filling has not passed the above tests) and the composite got a positive result;2) the filling material chosen, tested without the cover, has passed the above tests.Consequently, manufacturers of upholstered seating can request such certificates to their suppliers

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Franco Prete

of covers and fillings materials, and unless they are in possession, would do well to urge them, in the interests of the suppliers themselves.For products in general is also pro-vided a type approval certificate in accordance with procedures esta-blished by National Authorities that have to be based on the following criteria:

Mass produced itemsType approval certificates, valid for no more than 5 years, shall not be issued on the basis of test reports which are more than 5 years old. They are renewable without rete-sting provided that the test report is not more than 15 years old and no alteration of components or mate-rials and products has been made.The manufacturer is also required a quality control system audited by a competent authority to ensure conti-nuous compliance of products.

Not mass produced itemsFor products to be made for a spe-cific ship is not required the type ap-proval certificate, but the authorities may approve products using the

applicable test procedures. In these cases approval is only valid for a sin-gle delivery, intended for the specific ship.

It is possible to obtain a type appro-val certificate for products classi-fied under the old edition of the FTP Code, provided that the tests were carried out before July 1st, 2010. Furthermore, the type approval may be renewed for a product carried out with the previous version of the FTP Code, without the need for retesting, provided that the test reports are not over 15 years old and no alteration of components or materials and pro-ducts has been made.CATAS has asked the IMO acknowledgment to the Italian Au-

thorities in charge in order to per-form these tests.

European contextThe European Directive 96/98/EC requires the CE marking of products, which in this context has as its logo a rudder, and conformity assessment by Notified Bodies, with reference to Directive MED (Marine Equipment Directive), on the basis of specific procedures:- Module B: EC type-examination;- Module C: conformity to type;- Module D: production-quality as-surance;- Module E: product-quality assu-rance;- Module F: product verification;- Module G: unit verification;- Module H: full quality assurance.Modules for conformity assessment provided for upholstered furniture are:- Modules B + D;- Modules B + E;- Modules B + FNotified Bodies may be certifica-tion and/or inspection and/or testing Bodies. CATAS is not notified in this area.

Fire reaction tests are the same between the MED and SOLAS Con-vention, changing only the boundary conditions.

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidianaSurface cracking of coated MDF panels

Franco Bulian

IntroductionAmong the defects analysed at CATAS, one of the most frequent is that of the appearance of cracks on the surface of coated MDF, as in the case shown in figure 1.

Figure 1

Cracking occur almost always on moulded parts of the panel or along the edges.Very often, when a failure occurs, the problem is experienced by the companies involved as a quest for responsibility on either the panel or the coating system. However, in most cases, this apparent logic appro-ach does not lead to any concrete results especially in the view of future productions since the real “fault” is represented by a series of wrong choices or, at least, not adequately considered.Given the circumstances discussed above, this article tries to approach these cases, addressing the dyna-mics that lead to the genesis of the defect and then discussing the consequent strategies to avoid it in future productions.

Origin of cracksAs always happens, in order to understand the origin of a defect, it is necessary to firstly consider and know the characteristics of the materials used in the process.Let’s start from the MDF. These materials are well known consisting of wood fibres bonded together by means of hot-pressing and through the use of a thermosetting adhesive.The process is apparently simple but is indeed regulated by several variables affecting the finished pro-duct, which can be then produced with very different characteristics.The amount of adhesive, the wood species used, the times and the temperatures of the press can be adjusted producing panels very different from each other.Among the most important characteristics related to this variability it is possible to mention: the internal cohesion and the density profile.The internal cohesion is substantially the force that holds together the wood fibres depending, for exam-ple, by the amount of adhesive used. The density profile is the assessment of density of the panel along its thickness. Normally, in consequence to the pressing processes adopted, the density is not uniform being higher on the external surfaces and

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Franco Bulian

Figure 2. The image shows the procedure used for the determination of the internal cohesion, which is the tensile strength, perpendicular to the plane of the panel (EN 319)

tending to fall in the core of the panel. The density profile of an MDF is then graphically described by an arch (see figure 3) with a more pronounced curvature the greater is the difference in density between the outer surfaces and the core of the panel.It is probably already evident that these two properties (internal cohesion and density profile) are con-nected in some way and can greatly affect the defect we are dealing with. But before it is also important to consider the other material involved in the process, the coating.The types of coatings available are highly variable but, in relation to the defect here considered, they pre-sent a common behaviour being represented by their dimensional shrinkage during drying. In consequen-ce both to the evaporation of the solvents and to the crosslinking mechanisms, the volume of the coating tends to decrease after the application producing a mechanical stress on the panel surface.

Figure 3. Density profile of an MDF panel. The blue curve describes the density of the MDF panel along its thickness. It is possible to note the higher values on the surfaces in comparison to the core of the

panel

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidianaFranco Bulian

The mechanism appears very clear if we apply a coating material onto a sheet of paper. After drying, the sheet is no longer flat but tends to bend; the coating tightens and deforms the paper presenting the con-cavity towards the coated surface.The stress generated is much stronger the higher is the thickness of the paint also depending on its crosslinking degree and on its chemical nature.

We now have enough data to try to understand what happen when a shaped MDF is painted.As a result of the volumetric shrinkage, the dried paint generates a stress on the panel surface, which, in the moulded areas, can be also diversified depending on the variability of the coating thickness. The core of the fibre panel is also less dense and less cohesive. In certain situations these factors can reach a critical point and the panel starts to delaminate as evident in the following figure 4. In addition to those already mentioned a further critical element is represented by moisture. The MDF panels, mainly made of wood, are very sensitive to water tending to swell in an even greater extent than solid wood in consequence to the pressing, which they were subjected.The weakest areas of the panel, those of the inner moulded parts and where the stress of the coating film is higher, are also the parts most exposed to water absorption due to the poor protection provided by the coating film. Then a third critical factor is added to the previous determining a high risk of cracking to these areas as a result of the swelling caused by the water absorption.

Improvement strategiesWhat are the measures to counter the possible occurrence of cracks along the edges or moulded areas of coated MDF’s? In the following list we have tried to summarize the most important parameters that some companies know and have already considered in their internal procedures:

1. Use of MDF panels with a relatively uniform density profile. This causes the properties of the panel to be fairly homogeneous throughout its thickness. Therefore, the values of cohesion, the moisture absorption etc. will be similar between the surface and shaped areas of the panel.

2. Use of MDF with high internal cohesion. This property is measured according to EN 319 (tensile strength perpendicular to the plane). Here we must consider that there is also a limit value for this property given by another European Standard, the EN 622-5. This document specifies that for panels with a thickness range between 19 to 30 mm, the minimum value of tensile strength shall be 0.55 MPa. This limit, however, does not consider the specific processing and thus, for shaped panels a higher resistance than that mentioned above is recommended. The limit value to be considered could be that specified by EN 622-5 for panels to be used in wet environment (tensile strength perpendicular to the plane: 0.75 MPa).

3. Avoid the creation of angles close to 90 ° in shaped areas, preferring profiles with large curvature radii. This expedient, if achievable, reduces the differences in the coating thickness also avoiding the creation of sharp edges where the thickness of the paint is almost zero.

4. Always use a primer as first coat of the coating system. This application improves the cohesion of the fibres in the moulded areas in consequence of the penetrating action of the extremely diluted coating ma-terial. The primer also improves the resistance to water penetration especially in the areas of the panel that will receive a lower amount of paint.

Surface cracking of coated MDF panels

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Figure 4

ConclusionsThe short notes here presented about one of the most common defects occurring in the furniture sector, emphasize the importance of the knowledge on the materials with which companies work daily. The right selection is fundamental and, as pointed out in the last part of the article, not always a material can be considered “bad” or “non-compliant” in an absolute sense because its performance is also commensu-rate with the process performed on it and with its final destination.

BibliographyF. Bulian, Materials and Technology of the Furniture Industry, Goliardica Editrice, Trieste (2012)

Franco Bulian

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidiana

The book “Materials and Technologies of the Furniture Industry” has been translated into English

Staff CATAS

The vice-director of Catas, Dr. Franco Bulian, has recently translated into English his new book “Materials and Technologies of the Furniture Industry”.The book describes the composition, the features, the processes and the main defects associated with the funda-mental materials used by the furniture industry.The book is divided into six paragraphs namely:1. Wood + Appendix on Modified Wood2. Wood Based Panels + Appendix on Formaldehyde Emission3. Covering Materials (veneers, impregnated papers, laminates, polymeric foils)4. Edges5. Adhesives6. Coating MaterialsMore information can be directly asked to the author ([email protected]).The book is available in English or Italian languages directly at bookshops or at the following web site: www.edizio-nigoliardiche.it

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Alessia Matellon

Coating systems for exterior wood. Searching for a “very” accelerated test method

Introduction

The evaluation of the effectiveness in use of coating systems for exterior wood is normally carried out through aging trials. There are several methods of artificial aging, which may provide useful data for the comparison of different products.Unfortunately it is well known that the correlation with the real conditions is questionable for a number of factors that can not be artificially reproduced. An example? There are many: the effect of microorganisms, pollution, wind, ... so we know that the natural aging should not be missed as the only possible evidence of the actual effectiveness of the product.Then, in order to be particularly scrupulous, it too may be debatable, what is the best area of exposure? Well, trust me that the CATAS exposure site has a worthy of note! Fluctuations ... temperature, humidity ... a research project done some years ago showed that San Giovanni al Natisone is the most “severe” compared to other sites in Europe,One flaw of the test: the duration!A natural aging test has a minimum duration of one year, according to existing standards.But the market demands quicker answers and therefore it is necessary to move towards accelerated tests.The European standards propose an artificial aging test that allows a quick and complete assessment after 3 months.This is also the request of the producers of window frames aiming for a further accelerated aging being also a relia-ble method.

The products

Thanks to the cooperation of Sayerlack - Pianoro (BO), four coating systems (A, B, C, D) have been selected consi-dering their different and known performance in real use:A: old generation formulation with a very flexible resin;B: new generation formulation of excellent quality;C: cheap product;D: standard product.

The tests

A comparison with the natural aging (EN 927-3) was performed by the execution of the following accelerated tests:- Artificial aging by UV lamps (EN 927-6);- Artificial aging with xenon lamps (ASTM G 155-05);- Artificial aging with whell-method (Gardner method).

Details of the artificial aging cycles

The EN 927-6 provides the use of UVA lamps (340 nm) with a cycle divided into two steps. The first step consists in 24 hours of condensation at 45 ° C, the second step is based on a total of 144 hours divided into: - 2.5 hours of light (black panel temperature of 60 ° C) and UV irradiance of 0.89 W/m2 - 0.5 hours of water spraying. The complete cycle is repeated 12 times. The test duration is 2016 hours.

The American standard ASTM G 155-05 provides for the use of a xenon lamp. The irradiation is 0.35 W/m2; the temperature of the black panel is 60 ° C. The test consists of several cycles each lasting 24 hours, divided into:- 102 minutes of light - 18 minutes of light and water spray. The duration of the test for our experiment has been defined in 1000 hours.

The test according to the method of the Gardner Wheel consists of a cycle divided into:- 24 minutes of UV lamps 300 W, - the samples are kept at ambient temperature for 27 minutes- 12 minutes water immersion

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Franco Bulian



Alessia Matellon

- room temperature for 27 minutes. The cycle is repeated for 336 times. The total duration is therefore 3 weeks.

Furthermore, in order to intensify the effects and then further accelerating the test, the following measures were taken:- Test according to EN 927-6: one of the specimens was obtained after gluing two wood elements with perpendi-cular grain (see picture n. 1) and on another test piece was performed with a notch perpendicular to the direction of the grain;- Test according to ASTM G 155-05: one of the specimens was performed with a notch to X;

- Second test method Gardner: one of the specimens was performed with a X cut;- natural weathering: a groove (called Water Trap) of 20 mm in diameter and 5 mm deep as described in Annex E of EN 927-3 was done on some specimens.

Regarding the duration of the tests, it was considered not to exceed a maximum of 3 months, taking as reference the duration required by the European standard.In any case, the evaluations were performed on both the intermediate samples tested according to EN 927-6, and on those tested with the ASTM G 155-05, with the intention of evaluating the effects of aging on the “special” spe-cimens.

Results

1 - Assessment of artificial aging test

The assessments include:- The change of colour and gloss to the initial state;- All the defects classified according to the ISO 4628 (the presence of cracks, flaking, blistering and chalking) accor-ding to a rating scale from 0 (no defect) to 5 (very intense defect);

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Alessia Matellon

- Verification of specimen in accordance with ISO 2409 (cross-cut) on a scale from 0 (excellent adhesion) to 5 (poor adhesion);- Verification of specimens around the notch.

After about 1000 hours of exposure to UV lamps with aging according to EN 927-6, there were no defects redi-scounted useful to diversify the cycles, so in table no. 1 shows the results obtained only after the planned 2016 hours.The test with xenon lamps ASTM G 155-05 provides some useful data in the differentiation of cycles after only 500 hours, but it was agreed to continue the test until 1000 hours budgeted (Table no. 2).After the planned 504 hours of testing with UV lamps according to the method of the Wheel Gardner, in the same way have not been detected data interesting, in this case the test was prolonged for additional 504 hours. The re-sults are reported in Table n. 3.Results:

*near the joint line

Table n. 1 – Assessment of the samples after artificial weathering according to EN 927-6.

Coating Sy-stem A

Coating System B

Coating System C

Coating System D

Colour change (DE) 3,97 1,61 4,36 3,49

Gloss change 3,5 3,6 3,8 1,8

Cracking 0 0 0 0

Flaking 0 0 0 0

Blistering 0 0 0 0

Chalking 0 0 0 0

Adhesion 0 0 0 0

Adhesion (water trap) ok ok ok ok

Joined specimen ok ok Cracking and flaking (*)

Slight cracking (*)

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidianaAlessia Matellon

Coating System A

Coating Sy-stem B

Coating System C Coating Sy-stem D

Hours 500 1000 500 1000 500 1000 500 1000

Colour change (DE*) 7,59 11,00 7,07 6,78 4,92 2,67 3,87 2,26

Gloss change 8,1 -4,1 15,4 -10,2 18,0 -12,1 10,9 -1,0

Cracking 0 0 0 0 0 0 0 0

Flaking 0 0 0 0 0 0 0 0

Blistering 0 0 0 0 0 0 0 0

Chalking 0 0 0 0 0 0 0 0

Adhesion 0 0 0 0 0 0 0 0

Adhesion (water trap) yes yes no no yes yes no yes

Joined specimen ok ok ok ok ok negative ok ok

Table n. 2 – Assessment of the samples after artificial weathering according to ASTM G 155-05

* In the vicinity of the notch

Table no. 3 - Evaluation of the specimens tested Wheel Gardner

2 - Evaluation of the natural aging tests

As in the case of artificial aging, we evaluated the surfaces of the specimens for each parameter, then the cycles were classified according to what is defined by EN 927-2 “Paints and varnishes - products and coating systems for wood for outdoor use - Specification of performance. “ The classification provides a breakdown of the coating systems useful for products of: stable type, semi-stable type and not stable type, where the category “stable” is the one with the highest requirements.


Coating System A Coating System B Coating System C Coating System D

Hours 504 1008 504 1008 504 1008 504 1008

Colour change (DE*)

4,48 4,59 2,89 1,58 3,88 4,8 6,25 3,83

Gloss change 6,2 -14,5 -12,1 -22,0 5,5 -22,7 -4,0 -18,6

Cracking 0 0 0 0 0 0 0 0

Flaking 0 0 0 0 0 0 0 0

Blistering 0 0 3 3 0 0 3 (*) 3 (*)

Chalking 0 0 0 0 0 0 0 0

Adhesion 0 0 0 0 0 0 0 0

Adhesion (water trap)

ok ok ok ok ok ok ok ok

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Alessia Matellon

Considering carefully table n. 4 it can be noted that the adhesion assessment of the coating film with the cross cut method is able to differentiate the coating systems in accordance with the expected performance (according to the formulation criteria specified above). This is possible, however, only after 24 months of outdoor exposure.The figure is confirmed by the classification according to EN 927-2.A good differentiation is reached only with the “water trap” after a year of exposure. In this case, however, the best would be the coating system A. This evidence could be explained by the fact that system “A” is produced with a very flexible resin, which then follows in a better way the movements of the wood due to moisture and temperature changes and consequently does not give rise to film cracking.A high flexibility of the top coat film is not completely indicative of quality of the product since in reality other basic features are important for a coating system. Conversely, a high flexibility may mean a poor stackability (blocking tendence).

An explanation is due about the evaluations of cracking. The majority of the cracks observed are due to hail. The origin of the defect is “mechanical” and not due to movement of the film, It is then questionable if the ranking should be confirmed after 24 months.

Conclusion

The results of this study seem to show that the Gardner wheel method should be considered as unreliable. In fact it did not allow the diversification of the coating systems as expected. Even the use of damaged specimens has not allowed the identification, at least, of the best and the worst system. On the contrary, according to the assessment of the presence of blistering, such method would lead to a wrong assessment. Moreover the results of the Gardner wheel are not supported in any way by other methods.A satisfactory result was achieved with the tests carried out with xenon lamps using damaged specimens, only after 500 hours. The tests performed with UV using bonded specimens has provided a significant result, but only after 2016 hours.

Below we report the absolute values of colour and gloss variations assessed after the different tests. We compare the natural aging of 12 months with 500 hours and 2016 hours of xenon UV and 24 months of na-tural aging for 1000 hours and 2016 hours of xenon UV.

It would seem that neither artificial aging adopted reflects the effects you get outside. You could say that the method with UV lamps better follows roughly the trend of natural exposure.

In conclusion, it is confirmed that the sole evidence of artificial aging can not replace the natural aging test. May be such tests can be considered as a rough indication, but the results obtained can not be validated without other tests supporting them andd considering also other properties essential for the formulation of products suitable for exterior use.

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidianaAlessia Matellon


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2020


Sara Zanchiello (AREA SCIENCE PARK)Maurizio Marussi

The behavior of a plate wall brackets fixed to the wall and subjected to a load has been studied using a software for the analysis of the finite element. The coupling of a piece of furniture as in actual use was simulated. The aim of this study, which can be useful for addressing the choice of the type of hardware to be used, is to quantify the tensions, the deformations, the contact forces between the plate and the hanger and the reaction forces in correspondence of the wall fixings, using different modes of fastening and load different wheights. The cabinet and the hanger used have not been subject to evaluation, but have had only intended to urge the plate Wall brackets in the manner as close as possible to reality.

Plate used for the simulation:

Material: 1023 carbon steel plate (SS)Elasticity modulus:: 205000 N/mm2

Poisson coefficient: 0.29Density: 7858 kg/m3

Yield strenght: 282.69 N/mm2

Furniture used for the simulation:

Material: Wood based panel.Elasticity modulus: 3000 N/mm2

Poisson coefficient: 0.29Density: 159,99 kg/m3

Yield strenght: 20 N/mm2

Study of stress on a plate wall brackets

2121

Maurizio MarussiStudy of stress on a plate wall brackets

Details of the cabinet hook:

Rear view of the coupling system

View the furniture transparency

22

Maurizio Marussi

FIRST STUDY:The plate was bound on the two outer slots, simulating a system for attaching to the wall using screw with flat head having a diameter of 10 mm (picture 1)

Picture 1

At furniture were assigned uniformly distributed loads for each surface according to the norm EN 14749 relates to furniture for domestic use. (picture 2)

Loads applied:Bottom: 84.2 kg (2.5 kg/dm2)First shelf: 50.5 kg (1.5 kg/dm2)Second shelf: 33.6 kg ( 1,0 kg/dm2)Ceiling: 18.0 kg (0.5 kg/dm2)Total load: 186,3 kg

Picture 2

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Results:Von Mises strenght:The parameter has been calculated from the tensions of the plate (MPa or N/mm2) to assess if the material used has characteristics of yield strength higher than those generated by the forces considered.

Remarks:The loads measured on various points of the plate (244 209; 126,521; 236,731 N/mm2) indicate values below the yield stress of the material used which is 282.69 N/mm2.

Deformations:It was measured the deformation of the plate on the edge in contact with the hanger so as to evaluate how much the cabinet will deviate from the wall on which it will be mounted.

The furniture section loaded (scale of deformation: 10) Graph of the deformation of the mounting plate to the wall.

Remarks:The maximum deformation of the plate as measured at the hanger results to be of 0329 mm, a value consi-dered acceptable for a visual assessment of the cabinet.

24

Maurizio Marussi

Contact forces:Were calculated by the contact forces between the plate and the hanger in X direction (horizontal to the wall fastening of the cabinet) and in the Y direction (vertical to the wall fastening of the cabinet).The magnitude of these forces can be useful in the choice of the type of hanger and the method of attach-ment to the cabinet.

Remarks:The contact forces are calculated as follows: 239 N in the X direction and of 931 N in the Y direction.

Reaction forces:Reaction forces were calculated at the joining points between the plate and the wall, thus evaluating the stresses to which the wall and the fastening screws used must resist.

The reaction forces are detected:

The top of the mounting area of the slot near the hanger:X: 535 N, Y: 316 N, Z: 53.3 NBottom of the mounting area of the slot near the hanger:X: 112 N, Y: 670 N, Z: 167 NThe top of the mounting area of the slot farthest the hanger:X: 39.2 N, Y: 60.1 N, Z: 59.9 NBottom of the mounting area of the slot farthest the hanger:X: 3.5 N, Y: 4.66 N, Z: 54 N

Remarks:The extent of the reaction forces are concentrated almost exclusively in the fastening point near the hanger, the second fastening point has therefore mainly the function of avoiding the rotation of the bar keeping it horizontal.

25


SECOND STUDY:In this study, has been moved to a constraint of the plate on the button hole more internal of the hanger (picture 3), loads and methods are those used in the first study.

Picture 3

Results:Von Mises stressesThis parameter has been calculated from the tensions of the plate (Mpa N/mm2) to assess if the material used has characteristics of yield strength higher than those generated by the forces considered.

Tension measured values MPa N/mm2:293,505; 283,400; 260,516.

Remarks:The measured tensions greater than those of yield strength of the plate (282.69 N/mm2) highlight the critical points that may compromise the optimum fastening of the movable wall.

26

Maurizio Marussi

Deformations:The deformation of the plate was measured on the edge in contact with the hanger so as to evaluate how much the cabinet will deviate from the wall on which it will be mounted.

The furniture section loaded (scale of deformation: 10) Graph of the deformation of the mounting plate to the wall.

Remarks:The maximum deformation of the plate as measured at dell’attaccaglia results to be of 1.24 mm, a value which can be considered appreciable for a visual assessment of the cabinet.Contact forces:The contact forces are calculated to be considered equivalent to those of the first study.Reaction forcesWere calculated reaction forces at the points of attachment between the plate and the wall, thus evaluating the stresses to which it must resist the wall and the fastening screws used.

The reaction forces are detected:The top of the mounting area of the slot near the hanger:X: N 484, Y: 475 N, Z: 1970 NBottom of the mounting area of the slot near the hanger:X: 217 N, Y: 658 N, Z: 2221 NThe top of the mounting area of the slot farthest the hanger:X: 39.5 N, Y: 95.8 N, Z: 14.7 NBottom of the mounting area of the slot farthest the hanger:X: 5.37 N; Y: 105 N; Z: 111 N

Remarks:Compared with the first study, in this case the reaction forces are greater in the Z direction and the second fastening point participates most to the sealing plate.

27

THIRD STUDY:

The plate was constrained on the two outer slots (picture 4), the methods are those used for the first study with the exception of the loads applied on the cabinet, this time using the parameters of the standard EN 14073.

Picture 4

The cabinet has been assigned uniformly distributed loads for each surface according to EN 14073 refers to furniture for office use. (picture 5)

Load applied:

Bottom: 84.2 kg (2.5 kg/dm2)First shelf: 84.2 kg (2.5 kg/d m2)Second shelf: 84.2 kg (2.5 kg/dm2)Ceiling: 84.2 kg (2.5 kg/dm2)Total load: 336.8 kg

Picture 5


28

Results:Von Mises stresses:This parameter has been calculated from the tensions of the plate (Mpa N/mm2) to assess if the material used has characteristics of yield strength higher than those generated by the forces considered.

Tension values measured Mpa N/mm2: 439,539; 377,155; 227.375.

Remarks:The measured tensions greater than those of yield strength of the plate (282.69 N/mm2) highlight the critical points that may compromise the optimum fastening of the movable wall.Deformations:The deformation of the plate was measured on the edge in contact with the hanger so as to evaluate how much the cabinet will deviate from the wall on which is mounted.

The furniture section loaded (deformation scale: 10) Graph of the deformation of the mounting plate to the wall

Remarks:The maximum deformation of the plate as measured at the hanger results to be of 0.63 mm, a value consi-dered acceptable for a visual assessment of the cabinet.

Maurizio Marussi

29

Contact forces:Were calculated by the contact forces between the plate and the hanger in X direction (horizontal to the wall fastening of the cabinet) and in the Y direction (vertical to the wall fastening of the cabinet).The magnitude of these forces can be useful in the choice of the type of hanger and the method of attach-ment to the cabinet.

Remarks:The contact forces are calculated of 439 N in the X direction and 1710 N in the direction Y.

Reaction forces:Reaction forces were calculated at the points of attachment between the plate and the wall, thus evaluating the stresses to which it must resist the wall and the fastening screws used.


30

Maurizio Marussi

The reaction forces are detected:

The top of the mounting area of the slot near the hanger:X: N 926, Y: 833 N, Z: 134 NBottom of the mounting area of the slot near the hanger:X: N 491, Y: 975 N, Z: 319 NThe top of the mounting area of the slot farthest the hanger:X: 41.5 N, Y: 60.3 N, Z: 108 NBottom of the mounting area of the slot farthest the hanger:X: 38.5 N; Y: 37 N; Z: 77 N

Remarks: The magnitude of the reaction forces are concentrated almost exclusively in the fastening point near all’attaccaglia, the second fastening point has mainly the function of preventing the horizontal movement and rotation of the bar.

Conclusions:As can be seen from the studies performed here, using the virtual analysis it is possible to verify the forces generated by simply varying the parameters of constraint loads and size.So the choice of the type of hardware, the number and position of the wall fixings, can be made in function of the specific type of mobile, thus being able to provide useful indications operational final installer.As regards the analysis of the resistance of the plate by means of the voltages Von Mises, must specify that has been performed a study of the linear type, not considering therefore stiffness varia-tions caused by the shape and nature of the material. This means that even if the stresses exceed the yield strength, not necessarily the plate will give way. The examination further to do is to assess the amount of material which becomes plastic, which can be done by means of a study of non-linear type, we propose in the near future.

31

Franco Bulian


A couple of years ago a book entitled “PARQUET from design to installation (*)”was published. On my opinion this publication contains useful information for professionals working in the production and installation of wood floo-rings.In particular I found an interesting data referring to the values of thermal resistance of the layer of screed above the pipes for floor heating.For this type of system the book states a “rule” to achieve a sufficient heat supply to the environment, in order not to alter the economies of operating conditions provided for the plant floor and to maintain the temperature of the hea-ting fluid as low as possible. The thermal resistance of the screed layer overlying the pipes, of the possible layers of thermo-acoustic insulation and of the wood flooring, shall not be greater than 0.15 m2K/W and 0.18 m2K/W unless otherwise instructed by the manufacturer’s plant.In the following part, some examples are given in order to allow to roughly consider the contribution of wood floo-ring, in terms of thermal insulation to the overall combination of all materials forming the layer above the pipes. This contribution is estimated approximately at around 40÷50% of the total thermal resistance.

Elements of theory and examples:The relationship between thermal conductivity (λ) and thermal resistance (R) is defined by the following formula:

R = s/ λwhere:s : thickness of the element (m)λ : thermal conductivity (W/mK)In the case of a panel composed by multiple layers, with different materials and thicknesses, the total thermal resi-stance (Rtot) is calculated as the sum of the resistances:Rtot = R1 + R2 + … + Rn = s1/ λ1 + s2/ λ2 + …sn/ λn

ExamplesExamples of calculation of the thermal resistance as a function of the type of product:1) Elements in solid wood (oak) with a thickness of 14 mm and an average density of 700 kg/m3

R = 0,014/0,18 = 0,078 (m2K/W)2) Elements with two layers:- Cover: solid wood (oak) with thickness of 4 mm and mean value of density of 700 kg/m3

- Support: plywood fir with thickness of 6 mm and mean value of density of 500 kg/m3

R = 0,004/0,18 + 0,006/0,13 = 0,022 + 0,046 = 0,068 m2K/W

Material Density(Kg/m3)

Design thermal conductivity(W/mK)

Solid wood 700 0,18

Plywood 500 0,13

- Extract from table 3 of the UNI EN ISO 10456:2008 standard -

(*) Publication (only in italian version) produced by AIPPL Group and wood floors EdilegnoArredo / FederlegnoArre-do.

Paolo Tirelli

Wood flooring on heated screeds, what is their contribution in terms of thermal insulation?

3232


Paolo Tirelli

New disciplinary and Manual for the control and the correct use of cork caps

In January of last year and in March of this one, a new disciplinary and a technical manual for cork caps, that we consider useful for the operators in the food industry, were published.

The first publication entitled “New disciplinary on analytical methods for the control of the cork for oenological use” and the second one “The cork - technical manual for the proper use of caps” are available for free in their entirety at the following links:

1) http://www.sardegnaagricoltura.it/documenti/14_43_20110422111223.pdf;

2) http://www.ilsughero.org/public/press/12-Manuale% 20Sughero.pdf

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Franco Bulian

Il CATAS tra internazionalizzazione,innovazione e realtà quotidianaStaff Material ConneXion Italia

GET INSPIRED BY MATERIALS

GET INSPIRED BY MATERIALS is the section dedicated to innovative materials and devoted to all the companies and professionals looking for new material solutions and inspiration for their projects. This section, as well as the Material Point FVG, an information point where materials are exposed to be seen and touched by the visitor, is the new service born from the cooperation between CATAS and Material ConneXion Italia, the most important national research and consultancy centre on materials.

MC Index Number: 3687-08

Greenguard® certified breathable faux-leather textiles

Breathable faux-leather textiles composed of 100% polyurethane (PU) surface with 82% rayon and 18% polyester backing. The fabrics meet or surpass industry wear standards including bond strength, seam strength, and tear strength. These leathers are Greenguard® Certified and contain no PVC (polyvinyl chloride), POPs (persistent organic pollutants), PBDEs (polybrominated diphenyl ethers), or HFRs (halogenated flame retardants). They meet VOC standards and contain no plasticizers, heavy metals, stabilizers or phthalates and produce no toxic by-products with over 99% of solvents recaptured and recycled. They exceed 200,000 double rubs on the Wyzenbeek abrasion test. It meets ASTM D 737 for air permeability, SAE J855 for stretch and set, ASTM D 117 for tensile and tear strength, and are class A fire-rated according to ASTM E 84. These textiles are available in 33 yd (30 m) rolls, 54 in (1.3 m) wide, with weights ranging from 9.7 oz/sq yd (330 g/sq m) to 14.6 oz/sq yd (450 g/sq m) with an approximate thickness of 1 mm (0.039 in), available in 27 different colors. Any stains can be removed with an alcohol-based cleaner and the fabrics should be disinfected using a 5:1 water/bleach solution. Applications are for healthcare, hospitality, residential, office, marine, aviation, recreation and automotive.

3434


Staff Material ConneXion Italia


Fully recycable composite material

100% polypropylene self-reinforcing polymer (SRP) composite material, that is fully recyclable. It is created through a hybrid tape welding and coextrusion process. This material has a high stiffness and low density (0.78 g/cm3; for comparison: GMT (Glass Matt Thermoplastic) 30% glass is 1.1 g/cm3). It has good impact resistance even at very low temperatures (-40 °F) and it also does not splinter. It can be thermoformed in various shapes. The material can be obtained in tape, fabric or sheet form with maximal dimensions of 1200 mm (47.2 in) in width, 2400 mm (94.5 in) in length and thickness of 2 mm (0.078 in). Increased thicknesses are possible through a heat lamination process combining multiple sheets together. One limitation of this material is its inability to be formed into compound curves. This material has been used for construction, automotive applications as well as the fabrication of various consumer products.


Compact laminate panels (CPL) with patterned top layers

Compact laminate (CPL) panels that incorporate patterned textile top layers without the use of a protective top surface melamine film. These textured surfaces are produced by pressing with phenolic and kraft papers with the textile on both sides of the panel to prevent bowing. This technique is ideal for standalone panels on different support types. These surfaces have good wear, scratch, steam, and stain resistance. They have a superior resistance to heat and light. They have a standard size of 51 x 120 in (1300 x 3050 mm) and thickness of 0.02 in (0.6 mm), and comply with EN 14323 for standard HPL properties such as scratch, water and wear resistance, and have a UV resistance of >6 according to EN 15187. Available on request are FSC sourced papers and fire resistant versions. Applications are for doors, partitions, sliding walls, and furniture paneling.

3535

Title GLUING WOOD Purchase CATAS ([email protected])Author Alberto Bandel CATAS Subscriber € 35,00 + IVAEditor CATAS SpA Non CATAS Subscriber € 45,00 + IVA

Gluing Wood was written by dr. Alberto Bandel, one of the greatest European experts in the field of wood adhesives thecnology. Since the first edition (1994), the book has represented a good theoretical basis but, moreover, a signifi-cant working tool for all the manufacturers.The book is written in a simple style, with many practical examples, pictures and tables. The collaboration with CA-TAS (and in particular with ing. Speranza, dr. Giavon and dr. Bulian), especially for the normative parts, has completed the book also with some useful references to test methods and standards.The book is divided into three chapters: Adhesives in the wood Industry- Materials in the Wood Industry and Gluing Technologies) which contain different pharagraphs about subjects related both to the raw materials and the working processes.

Title THREE DIMENSIONAL STRUCTURE OF WOOD. A scanning Electron Microscope StudyAuthors B.A. Meylan and B.G. Butterfield Purchase CATAS ([email protected])(Italian translation by Angelo Speranza) CATAS Subscriber € 25,00 + IVAEditor CATAS SpA Non CATAS Subscriber € 45,00 + IVA

This book is a collection of scanning electron microscope photographs selected to illustrate various features of the structure of wood. Althought is intended to supplement general plant anatomy texts for Botany and Foresty students at the upergraduate level, it should also be useful work for anyone interested in wood science.The lists of further reading included in each section contain only general texts and revelant paper on each topic.

Title WOOD COATINGS. THEORY AND PRACTICE Authors Franco Bulian and Jon Graystone Purchase Specialised bookstores - Language English Internet web sites: www.elsevier.com,Editor Elsevier www.amazon.com

Wood Coatings, written by Franco Bulian (CATAS) and Jon Graystone (Paint Research Association) addresses the factors responsible for the performance of wood coatings in both domestic and industrial situations. The term ‘wood coatings’ covers a broad range of products including stains, varnishes, paints and supporting ancillary products that may be used indoors or outdoors. Techniques for coating wood go back many centuries but in recent decades there has been a move towards more environmentally-friendly materials, for example, the use of water-borne rather than solvent-borne chemicals. A major objective of Wood Coatings is to explain the underlying factors that influence selection, application and general operational issues. Basic information on the chemistry and technology of coatings is included for the benefit of students and laboratory technicians. Additio-nally, the book includes individual chapters of interest to architects, specifiers, and industrial users.

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Notizie CATAS n.3 2012