EP3941316A1

EP3941316A1 - Antimicrobial wood material-based piece of furniture with a plastic laminate coating as well as method for coating a piece of furniture with an antimicrobial plastic laminate coating

Info

Publication number: EP3941316A1
Application number: EP20777036.3A
Authority: EP
Inventors: Kari Soljamo
Original assignee: Isku Interior Oy
Current assignee: Isku Interior Oy
Priority date: 2019-03-22
Filing date: 2020-03-20
Publication date: 2022-01-26
Also published as: FI20195212A1; EP3941316A4; WO2020193855A1; FI129411B

Abstract

The invention relates to an antimicrobial wood material- based piece of furniture (1, 2, 3, 5) with a plastic laminate coating, comprising a plastic laminate coating placed on a furniture surface, preferably on a contact surface, and hav ing a thickness of 0,4-1,4 mm, and said laminate coating comprising one or more overlapping films (64¹... 64⁶), each of said films consisting of paper impregnated with resin, especially melamine resin or polyester resin. In the invention, the piece of furniture has its plastic laminate coating provided with antimicrobial activity at least against S.aureus and E.coli, whereby the plastic laminate coating, when tested according to standards ISO 22196 or J IS Z 2801, has antimicrobial activity which eliminates at least 95% of bacteria used in the test, the antimicrobial activity of the piece of furniture's plas tic laminate coating has been achieved by impregnating one or more films of the plastic laminate coating with at least one resin batch which has been supplemented with a silver-containing adjuvant in such an amount that each sil ver-containing film of the laminate coating contains silver 0,005-0,1% by weight calculated from the total weight of resin incorporated in each silver-containing film, and the plastic laminate coating's antimicrobial activity has been achieved by impregnating paper, comprising a top most film of the plastic laminate coating, especially deco rative paper, with several resin batches, whereby the final resin batch has been supplemented with a silver- containing adjuvant in such an amount that the laminate coating's topmost film contains silver 0,005-0,1% by weight calculated from the total weight of resin batches contained in said topmost film.

Description

Antimicrobial wood material-based piece of furniture with a plastic laminate coating as well as method for coating a piece of furniture with an antimicrobial plastic laminate coating

The invention relates to a piece of furniture as set forth in claim 1 , such as a table, a chair, or a reception desk, which is coated with a plastic laminate coating that has antimicrobial activity at least against S.aureus and E.coli.

Treatment with antimicrobial silver of a high pressure laminate used on flat surfac es is known as such, and even a few respective low pressure laminates have been presented in patent literature.

However, the intended field of use for prior known laminates has predominantly in cluded rather large surfaces and panels, whereby the antimicrobial treatments re quired by such flat surfaces have been based on ensuring specific antimicrobial treatment effectiveness rather than so much on cost effectiveness in the process of manufacturing individual pieces of furniture. In furniture, the laminate surfaces may constitute a relatively small part of the furniture, yet the cost of a silver treat ment required thereby may rise to high level. The latter problem is particularly no table as a result of today’s heightened cost and hygiene regulations for furniture used e.g. in public facilities such as schools as well as waiting areas in health clin ics.

It is an objective of the present invention to eliminate or at least alleviate problems occurring in the above-described prior art.

Therefore, it is a main objective of the invention to provide a cost-effective way of manufacturing & treating with silver compounds rather small laminate surfaces, used specifically in furniture, to render the same antimicrobial, and furniture so treated.

Another objective in the invention is to provide a method for treating furniture in such a way that the furniture has always at least a specific bacterial growth and multiplication reducing activity in a space in which it has been set up, when com pared with the respective untreated furniture.

It is by means of an antimicrobial piece of furniture according to the invention, which includes a plastic laminate coating, that the foregoing objectives are at tained. Accordingly, the invention relates to an antimicrobial wood material-based piece of furniture of claim 1 , which has been coated with a plastic laminate coating. The piece of furniture is preferably a table, a chair, or a reception desk.

More specifically, the invention relates to an antimicrobial wood material-based piece of furniture with a plastic laminate coating, comprising a plastic laminate coating placed on a furniture surface, preferably on a contact surface, and having a thickness of 0,4-1 ,4 mm, and said laminate coating comprising one or more overlapping films, each of said films consisting of paper impregnated with resin, especially melamine resin or polyester resin. Hence the piece of furniture has its plastic laminate coating provided with antimicro bial activity at least against S.aureus and E.coli, whereby the plastic laminate coat ing, when tested according to standards IS022196 or JIS Z 2801 , has antimicrobi al activity which eliminates at least 95% of bacteria used in the test, the antimicrobial activity of the piece of furniture’s plastic laminate coating has been achieved by impregnating one or more films of the plastic laminate coat ing with at least one resin batch which has been supplemented with a silver- containing adjuvant in such an amount that each silver-containing film of the lami nate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin incorporated in each silver-containing film and the plastic laminate coating’s antimicrobial activity has been achieved by im pregnating paper comprising a topmost film of the plastic laminate coating, espe cially decorative paper, with several resin batches, whereby the final resin batch has been supplemented with a silver-containing adjuvant in such an amount that the laminate coating’s topmost film contains silver 0,005-0,1 % by weight calculat ed from the total weight of resin batches contained in said topmost film.

One preferred embodiment of the invention comprises a table with plastic laminate coating, whose wooden tabletop has its topside provided with a plastic laminate coating and the wooden tabletop has its underside adjoined by one or more wood en table legs or metal legs. The plastic laminate coating of the wooden tabletop has a thickness of 0,4-1 , 4 mm and the plastic laminate coating includes overlap ping film layers, each of said films comprising a resin-impregnated paper layer, whereby at least one of the plastic laminate coating’s film layers, one of which is a topmost film layer of the plastic laminate coating, contains silver (Ag) altogether 0,005-0,1 % calculated from the weight of resins used for constructing each silver- treated film layer of the plastic laminate coating.

Thus, the silver-treated film layer contains silver (Ag) altogether 0,0015-0,4% cal culated from the weight of silver-containing resins.

Another preferred embodiment of the invention relates to a reception desk, includ ing a plate-like worktop made predominantly from wood material and comprising an upturned cover of the worktop and an underside of the worktop, said underside being directly adjoined by a base made of wood material and directed downward from the desk’s worktop. The worktop’s surface, proximal to the cover, is provided with a plastic laminate coating and the underside of said worktop is adjoined by a base which is manufactured from wood material and comprises a wooden surface coated with plastic laminate or plastic film.

The worktop has its plastic laminate coating and the base has its plastic laminate coating or plastic film provided with antimicrobial activity at least against S.aureus and E.coli.

The plastic laminate coating includes overlapping film layers, each of said films comprising a resin-impregnated paper layer. Thus, at least one of the plastic lami nate coating’s film layers, one of which is a topmost film layer of the plastic lami nate coating, contains silver (Ag) 0,005-0,1 % calculated from the total weight of resin used for constructing each silver-treated film layer of the plastic laminate coating.

The base’s plastic film is a self-adhesive melamine film having a thickness of 0,2- 1 mm. The plastic film is made up of overlapping film layers and the plastic film contains silver (Ag) 0,005-0,1 % by weight calculated from the total weight of resin used for constructing each silver-treated film layer.

Still another referred embodiment of the invention relates to a seat panel’s topside coating for a wood-framed chair or to a backrest coating, which comprises a plas tic laminate coating. The plastic laminate coating has a thickness of 0,4-1 ,4 mm and said plastic laminate coating includes overlapping film layers, each of said films comprising a resin-impregnated paper layer, whereby at least one of the plastic laminate coating’s film layers, one of which is a topmost film layer of the plastic laminate coating, contains silver (Ag) altogether 0,005-0,1 % calculated from the total weight of resin used for constructing each silver-treated film layer of the plastic laminate coating. Preferably, a bulk of said antibacterial silver (Ag) has been impregnated into the topmost decorative paper of a plastic laminate coating.

In yet another preferred embodiment of the invention, the plastic laminate coating has its topmost paper, such as decorative paper, provided with a gradient, which contains antibacterial silver (Ag) and in which the amount of silver increases when proceeding in the decorative paper from interior to surface layer.

In the last-mentioned embodiment of the invention, the decorative paper has been twice impregnated with resin, such as melamine resin, and it is only the final resin batch that has been supplemented with a silver-containing adjuvant. This final res in batch contains silver in such an amount that the resulting amount of silver in decorative paper will be about 0,005-0,1 % by weight calculated from the total weight of resin used for impregnating the plastic laminate coating’s decorative pa per. Hence, the decorative paper is provided with a silver gradient with only the thin surface layer of decorative paper containing silver while the interior of decora tive paper is impregnated with resin, such as melamine resin, not containing an adjuvant.

Preferably, the plastic laminate is a low pressure laminate, wherein the paper lay ers are first impregnated with resin and thereafter the overlapping paper layers are pressed against each other with a compression pressure of 2.0 Mpa. The inven tion is preferably implemented by using a continuous roll lamination process and for thin laminates the compression pressure is not more than 2.0 Mpa and for thicker laminates the compression pressure is preferably 2-4 Mpa.

In one preferred embodiment of the invention, it is additionally at least one vertical edge of a wooden tabletop or a reception desk’s worktop which is provided with an elongated polymer rim which is either an edge strip or an edge molding. The pol ymer rim is provided with antimicrobial activity at least against S.aureus and E.coli and it has a thickness of 0,5-5 mm, whereby the resin used for constructing the polymer rim has been supplemented with a silver-containing adjuvant in such an amount that the polymer rim contains silver (Ag) 0,005-0,1 % by weight calculated from the total weight of resin treated with a silver-containing adjuvant and used for constructing said polymer rim.

The edge strip is an elongated polymer rim, which is prepared from polyester- based or acrylobutadiene styrene-based resin and has a thickness of 0,5-4 mm, preferably 1 -2 mm, and the edge strip contains silver (Ag) 0,005-0,1 % by weight calculated from the total weight of resin used for constructing the polymer rim.

The polymer casting is an elongated polymer rim, which is prepared from polyure thane-based resin (polyol + isocyanate) and has a thickness of 1-5 mm and con tains silver (Ag) 0,005-0,1 % by weight calculated from the total weight of resin used for constructing the polymer rim.

The concept antimicrobial coating is used here in reference to a plastic, paint, lam inate or composite coating, which has been tested in accordance with ISO 22196 or JIS Z 2801 and which eliminates at least 95% of bacteria used in the test and coming into contact with such a coating.

Resin (e.g. polyester resin, ABS resin, polyurethane resin) in the present invention refers to a resin, which is intended for the lamination of paper layers and which comprises the structural components of polymer (among others, monomers, pre accelerated polymer, etc.) a possible accelerator and a catalyst.

The present invention is primarily based on having the plastic laminate coating of a piece of furniture, such as a table, a chair or a desk (such as a reception desk), provided with an antimicrobial activity-imparting silver compound in such a way that the plastic laminate coating fulfills the requirements of the aforementioned ISO 22196 or JIS Z 2801 antimicrobiality test.

The plastic laminate may thus preferably be a low pressure laminate, wherein the paper layers are first impregnated with resin and thereafter the overlapping paper layers pressed against each other with a compression pressure of less than 4.0 Mpa. It is often more cost-beneficial in furniture to use low pressure laminates than high pressure laminates since the life cycle of furniture is often relatively short.

The amount of silver in a plastic laminate coating is maintained at low level by only supplementing its surface layers, preferably decorative paper, with silver com pounds in a very small quantity (only about 0,005-0,1 % by weight) calculated from the weight of resin batches used for impregnating the silver-containing paper layer.

Thirdly, the very small amount of silver compound notwithstanding, the antimicro bial efficacy of added silver compounds has been ensured by using silver com pounds preferably bonded to a carrier. A benefit attained by these procedures is that the contact surfaces of furniture will only be supplemented precisely with such an amount of silver compounds by which can be ensured adequate antimicrobial activity in furniture, for example in fixtures under public management (e.g. schools, health clinics, etc), yet the costs of silver treatment remain low.

Preferably, the selected contact surfaces of a piece of furniture have been sup plemented with silver compounds in such an amount and in such a form that the antimicrobial effectiveness of the silver compounds on the contact surfaces against specific pathogenic bacteria measures up to the antimicrobial activity de termined by ISO 22196 or JIS Z 2801 against selected pathogens. The selected pathogens include at least S.aureus and E.coli. According to the aforementioned test protocol, the active agent is required to have such an antimicrobial activity suf ficiently effective to kill 95% of the selected pathogens from any given antimicrobi- ally treated surface as compared to an untreated surface.

The contact surfaces in a table to be treated with silver include a plastic laminate coating-equipped topside of the tabletop and, in a reception desk, a plastic lami nate coating-equipped topside of the worktop. In addition, the treatment can be applied to polymer coating-equipped vertical edges abutting on a table’s tabletop and a desk’s worktop.

In chairs, on the other hand, the contact surface to be treated may comprise a seat panel and a backrest, which are provided with an antibacterial plastic laminate coating.

Thus, in the invention, the desk, table or chair has a selected contact surface coated with plastic laminate. Such plastic laminated-coated contact surface is a topside of the tabletop, a topside of the desk’s worktop, a seat panel of the chair, a backrest of the chair, or an armrest of the chair.

The invention relates also to a plastic laminate coating for use on a contact sur face of furniture. The plastic laminate coating includes overlapping film layers, each of which comprises at least one resin-impregnated paper layer.

The plastic laminate coating consists of several overlapping film layers, each of said film layers comprising a film made up of a resin-impregnated paper lay er/paper layers.

To the plastic laminate coating has been imparted antimicrobial activity preferably by only supplementing the resin, impregnated into the plastic laminate’s topmost decorative paper, with 0,005-0,1 % by weight silver in the form of a carrier-bonded silver compound. The resin consists preferably of melamine resin or polyester res- in. The amount of silver is calculated from the total weight of resin batches added into the decorative paper.

Each film layer is here perceived to consist of a film, in which the same polymer resin is used for impregnating the same type of paper. Thus, one and the same film may include several identical paper layers on top of each other as long as those have been impregnated with the same resin material.

The carrier-bonded silver compound consists preferably of silver phosphate glass, wherein the content of silver is 0,1 -10 mol%, preferably 0,5-5 mol%, even more preferably 0,5-2 mol%.

One preferred embodiment of the invention comprises a plastic laminate coating, which has a thickness of 0,4-1 ,4 mm and is intended for coating furniture. The plastic laminate coating includes overlapping film layers, each of said films com prising a resin-impregnated paper layer, whereby at least one of the plastic lami nate coating’s film layers, one of which is a topmost film layer of the plastic lami nate coating, contains silver (Ag) altogether 0,005-0,1 % calculated from the total eight of resin incorporated in each silver-containing film of the plastic laminate coating.

In the last-mentioned embodiment of the invention, the decorative paper has been twice impregnated with resin, such as melamine resin, and it is only the final resin batch that has been supplemented with a silver-containing adjuvant. Hence, this final resin batch contains silver about 0,015-0,4% by weight calculated from the weight of the final resin batch, such as a melamine resin batch. Thus, the decora tive paper is provided with a silver gradient with only the thin surface layer of deco rative paper containing silver while the interior of decorative paper is impregnated with resin, such as melamine resin, not containing an adjuvant.

Therefore, the silver-treated film layer contains silver (Ag) altogether 0,005-0,1 % calculated from the total weight of resin, i.e. all resin batches, incorporated in the silver-containing film. Additionally, in another preferred embodiment of the invention, the polymer rim of a table or desk is rendered antimicrobial by supplementing, in the casting process of a polymer molding, the polyurethane resin with such an amount of carrier- bonded silver compound. The polymer rim, manufactured from a polyurethane molding, has a thickness of 1-5 mm and contains silver 0,005-0,1 % by weight calculated from the weight of polyurethane resin used for casting said polymer rim.

In yet another preferred embodiment of the invention, the polymer rim of a table or desk is an edge strip, which is rendered antimicrobial by supplementing the edge strip-forming polyester resin or ABS resin, in the edge strip manufacturing process, with a silver compound in such an amount that the edge strip, which has a thick ness of 0,5-4 mm, contains silver 0,005-0,1 % by weight calculated from the weight of polyester resin or ABS resin used for manufacturing the edge strip.

The invention will now be illustrated further with reference to the accompanying figures.

Figs.1 A and 1 B each shows, in a perspective view, a multi-legged table and two sets of slightly different chairs present on the opposite sides of a tabletop of this table.

Fig. 2A shows, in a perspective view, an electric table equipped with adjustment legs, and a group of customer chairs as well as an office chair around the same.

Fig. 2B further illustrates, in a diagonal overhead view, the electric table of fig. 2A by itself.

Fig. 2C in turn shows, in a diagonal overhead view, the office chair depicted in fig. 2A.

Fig. 3 shows, in a diagonal overhead view, a set of furniture which includes a table with a leg post and four customer chairs around the same.

Fig. 4A shows a pair of customer chairs, which can be used in the sets of furniture shown in figs. 1 A, 1 B or 2A to replace the sets of customer chairs visible therein.

Figs. 4B and 4C show various customer chairs which can be used in the sets of customer chairs visible in figs. 1 A, 1 B and 2A.

Figs. 5A and 5B each illustrates office premises with several sets of furniture of the invention placed therein. Fig. 6 shows a reception desk and office chairs used in connection therewith.

Figs. 7A-7G show schematically various contact surfaces provided with antimicro bial treatments.

Next follows a review of the structures presented in figs. 1-7 and which aspect of the invention is intended to be illustrated by each figure.

Fig. 1A shows, in a perspective view, an antimicrobial fixture assembly of the in vention, which is set up in one and the same office space. Fig. 1 A depicts a table 3 and four customer chairs 1 ; 1¹-1⁴ around the same, said group of customer chairs 1¹— 1⁴ being adapted for use together with said table 3. The group of customer chairs includes two sets of customer chairs on opposite sides of the table. The first set of customer chairs consists of customer chairs 1 ; 1¹ and 1 ; 1² and the second set of customer chairs consists of customer chairs 1 ; 1³ and 1 ; 1⁴ , said sets of customer chairs being placed on opposite sides of the table’s 3 tabletop 31.

The table 3 includes a tabletop 31 fabricated from wood material, such as for ex ample solid wood or furniture board. The tabletop 31 has its topside 31 a coated with a melamine-based first plastic laminate 310c and its underside is coated with a likewise melamine-based second plastic laminate or with mere backing paper. Each plastic laminate coating has a thickness of about 0,8 mm. It is only the up side plastic laminate coating 310c of the tabletop 31 which is supplemented with an antimicrobial silver compound in a manner similar to that explained in fig. 7C and its description for producing an antimicrobial plastic laminate coating 310c, 64.

In this case, a topmost surface film 64¹, 64a was excluded completely from the plastic laminate and was replaced by impregnating a topmost decorative paper 64², 64b (cf. fig. 7C) once or twice with melamine resin.

The silver-containing silver phosphate glass contained silver 0,1-10 mol%. The employed silver phosphate glass had a general formula Ca3oNa2o-xP5oAg_x, wherein x = 0,1-10, preferably x = 0,5-5. Silver phosphate glass was preferably incorpo rated only into a resin batch used for the latter impregnation of decorative paper. This enabled formation on top of the decorative paper of a thin surface film which contained silver compound. Therefore, after treatment, the tabletop’s 31 plastic laminate coating 310c had the thin surface layer of its topmost decorative paper 64b (cf. fig. 7C) containing silver about 0,005-0,1 % by weight calculated from the weight of a silver-treated resin batch added into the surface layer of decorative paper. The final resin batch used for impregnating decorative paper contained in this case approximately 0,015-0,4% by weight silver (Ag) and the decorative paper itself approximately 0,005-0,1 % by weight silver calculated from all resin batches used for the impregnation of decorative paper.

Between the topside and underside plastic laminate coatings of the table’s 3 tab letop 31 is left an end face (edge) area of the wooden tabletop 31 of the table 3, the vertical plane passing therethrough being transverse relative to the plane of the tabletop’s 31 topside 31 a. The end face of a tabletop 31 , shown in fig. 1 A, has its vertical edge 33 formed with an elongated polymer rim 33d, which is co- directional with a top edge of the tabletop and fashioned into an antimicrobial pol ymer rim 33d, 63. The polymer rim 33d of the edge 33 can be either an edge molding 33f made of polyurethane or an edge strip 33e made of polyester resin or ABS resin (cf. fig. 7G). An antimicrobial silver compound, such as the aforemen tioned silver phosphate glass, having a general formula Ca3oNa2o-xP5oAg_x, wherein x = 0,1 -10, especially 0,5-5, is added, in the manufacturing process of the poly mer rim 33d, into polyurethane resin (edge molding) or polyester resin(edge strip) making up the polymer rim 33d, in a manner similar to that illustrated in connection with the description of fig. 7G.

From a set panel 10 of each chair 1 rises a continuous back support 1 1 , which is simultaneously a backrest 1 13. The upward-directed back support 1 1 is wood framed and coated with a plastic laminate 1 1 c over each side thereof. The plastic laminate coating 1 1 c of the backrest/back support has been treated into an antimi crobial plastic laminate coating 1 1 c, 64 with a silver compound such as silver phosphate glass. Fabrication of the plastic laminate coating 1 1 c and rendering the same antimicrobial have been described later in more detail in connection with fig. 7C. Films 64¹... 64⁶ (cf. fig. 7C) for the plastic laminate coatings 1 1 of chairs 1 ; 1 ¹ , 1 ; 1², 1 ; 1³, 1 ; 1⁴, presented in fig. 1 A, are all based on polyester resin.

Alternatively, the films 64¹... 64⁶ for a plastic laminate coating of the back sup port/backrest 1 1 , 1 13 can be produced by impregnating papers of the backrest/back support’s 1 1 , 1 13 plastic laminate with melamine resin.

In these antimicrobial plastic laminate coatings, either the topmost decorative pa per 64², 64b, the topmost decorative paper 64², 64b as well as the topmost sur face film 64¹ , 64a, or all films 64¹... 64⁶ had been impregnated with polyester resin (or melamine resin) at least once (cf. fig. 7C). The polyester resin had been supplemented with carrier-bonded silver compounds (in the form of silver phosphate glass or zeolite-bonded silver) for enabling an an timicrobial treatment. The amount of antimicrobial silver in all treatments was 0,005-0,1 % by weight calculated from the total weight of resin batches included in all paper layers treated with a silver-containing adjuvant. Generally, however, sil ver was only incorporated in a resin batch/resin batches, which was/were impreg nated into the topmost decorative paper.

The contact surfaces of chairs 1 ; 1¹ and 1 ; 1⁴ further include surfaces of armrests 14 coupled with the legs 13 and/or the back support 1 1 of these chairs. Horizontal armrest components 14c of the armrests 14 are fabricated from compression molded thermosetting plastic. The resin used for a compression molded part has been supplemented during fabrication process with a microbicidal, carrier-bonded silver compound, especially silver phosphate glass, in such an amount that the compression molded part of the armrest components 14c contains silver (Ag) 0,005-0,1 % by weight calculated from the weight of resin used for the compres sion molded part.

Fig. 1 B reveals, likewise in a perspective view, another antimicrobial fixture as sembly of the invention, which is set up in one and the same office space. Fig. 1 B shows also a table 3 and four customer chairs 1 ; 1¹-1 ; 1⁴ around the same, said group of customer chairs 1 ; 1¹-1 ; 1⁴ being adapted for collective use with said ta ble. The group of customer chairs includes two sets of customer chairs on oppo site sides of the table, being placed on opposite sides of the table’s 3 tabletop 31.

In this case, as well, the table 3 includes a rectangular-shaped tabletop 31 fabri cated from wood material, for example from solid wood or furniture board.

The furniture board refers in this application to a core material for the tabletop or the desk’s worktop, which may consist of chipboard, plywood, or fiberboard, espe cially mdf board.

The tabletop 31 has its topside 31 a, as well as also its underside, provided with a wood veneer overlay 310b whose thickness is 0,5-4 mm, preferably 0,6-1 ,5 mm. The tabletop’s topside 31 a has its wood veneer overlay 310b provided with an an timicrobial paint or lacquer coating 61 whose total film thickness is 40-120 pm, depending on the amount of binder in the paint or lacquer coating, as well as on the number of paint/lacquer layers (each paint/lacquer layer, upon drying, devel ops a film which has a film thickness of 20-40 pm). The paint or lacquer coating has been supplemented with carrier-bonded silver 0,005-0,1 % by weight calculat ed from the dry weight of the paint or lacquer coating’s paint/lacquer layers. It is generally only the topside 31 a of the tabletop 31 which has the paint or lacquer layers of its wood veneer overlay 310b supplemented with an antimicrobial silver compound in a manner similar to that illustrated in figs. 7D-7E. There are projects, however, in which the tabletop has the wood veneer overlay of its underside also provided with an antimicrobial paint or lacquer coating 61 .

Between the topside and underside wood veneer overlays of the table’s 3 tabletop 31 is left a vertical edge 33, which is perpendicular to the plane of the tabletop’s 31 topside 31 a. The tabletop 31 can have its end face 33 formed with an elongated antimicrobial polymer rim 33d, 63 which is co-directional with a top edge 31 b of the tabletop and similar to that already described earlier in connection with fig. 1 A.

Instead of a polymer rim 33d, the tabletop 31 may have its vertical edge 33 also provided with a separate wooden strip for making an edge strip (not shown in the figures). The edge strip can be thereafter provided with an antimicrobial wood paint coating such as a lacquer coating. Treatment of the wood paint coating to render it antimicrobial can be conducted in a manner similar to that explained in connection with figs. 7D-7E and the description thereof.

The table 3 depicted in fig. 1 B has the underside of its rectangular-shaped wooden tabletop 31 adjoined at the corners of the tabletop 31 by a group of four wood- constructed table legs (edge legs) 34; 34b. Each edge leg 34b has an antimicrobi al wood paint coating 61 b. Treatment of the wood paint coating to render it antimi crobial can be conducted in a manner similar to that explained in connection with figs. 7D-7E and the description thereof. The antimicrobial wood paint coating 61 b is thus formed on the table leg 3; 34b by spraying or otherwise applying paint or lacquer onto each table leg 34; 34b for one or more uniform paint layers having a wet thickness of about 100 pm (dry thickness about 20-40 pm). The selected paint layers contain a silver-containing, antimicrobial, carrier-bonded compound, such as zeolite or silver phosphate glass. Silver phosphate glass or zeolite is admixed into the wood paint in such an amount that each selected paint layer, particularly the topmost paint layer, when dry, contains silver 0,005-0,1 % by weight of said dry paint film’s dry weight. Therefore, in practice, the topmost paint layer used for the surface treatment of a product should contain silver preferably 0,005- 0,1 % by weight of the dry weight of a binder contained in the paint. A plastic laminate coating 64 for the backrests of chairs 1 ; 1³ and 1 ; 1⁴ has been fabricated and rendered antimicrobial in a manner similar to that presented in fig. 1A for the plastic laminate coatings of chairs 1 ; 1¹, 1 ; 1², 1 ; 1³, 1 ; 1⁴. In this case, as well, the plastic laminate coating 64 may have all its films 64¹... 64⁶ based on polyester resin or melamine resin as illustrated later in fig. 7C and its description.

Both all edges (rims) 105 of the seat panel 10 and all edges 1 15 of the back sup port 1 1 have been treated with an antimicrobial furniture lacquer 62 in the same way as in the working example presented in fig. 1A. These edges are perceived as contact surfaces in the customer chairs 1.

Fig. 2A reveals, in a perspective view, a two-legged, so-called electric table 3 and fig. 2A shows two customer chairs 1 around the electric table 3, as well as one of fice chair 2. For the sake of clarity, the electric table 3 of fig. 2A is further shown by itself in fig. 2B and the office chair 2 of fig. 2A is shown by itself in fig. 2C. Next de scribed will be details of the invention visible in these figures 2A, 2B and 2C.

The electric table 3 has its tabletop 31 made of furniture board which is coated over its top- and undersides with a plastic laminate coating 310c (the underside may also be coated only with backing paper). The electric table 3 has its topside 31 supplemented, during the preparation process of the plastic laminate coating 31 ; 310c, with silver compounds in such an amount that the plastic laminate coat ing 31 ; 310c has been rendered antimicrobial. A plastic laminate coating 320c (or backing paper) of the electric table’s 3 underside 31 b is not considered a contact surface, which is why it is generally excluded from being treated with antimicrobial silver compounds or the like. There are applications, however, in which the tab letop’s underside can also be treated to make it antimicrobial.

Preparation of the topside plastic laminate coating 310c for the electric table’s 3 tabletop 31 and rendering said laminate coating antimicrobial were conducted in a manner similar to that explained in connection with the description of figs. 1A and 7C. The electric table 3 had all vertical edges 33 of its tabletop 31 supplemented with a polymer rim 33d into which were added microbicidal silver compounds in such an amount that the polymer rim 33d was found to possess the antimicrobial activity determined in standards ISO 22196 or JIS Z 2801 against selected patho genic bacteria. The antimicrobial polymer rim 33d, 63, containing silver com pounds, was fabricated in a manner similar to that described in connection with the table shown in fig. 1A. The actual fabrication of a polymer rim 33d, 63 and the ad dition of silver compounds into the polymer rim are explained in more detail in fig. 7G and its description. With regard to options of manufacturing the plastic laminate coating 64 for the table’s 3 tabletop 31 and fabrication of the antimicrobial polymer rim 63, reference is indeed made to figs. 1A, 1 B and 7C, 7G and the description thereof.

The electric table 3 has its underside adjoined by two metallic, height-adjustable table legs 35; 35c which have been treated by powder painting. The electric table’s 3 legs 35c, equipped with an adjustment mechanism, are not generally regarded as contact surfaces and, therefore, the powder paint coating thereon has not been supplemented with microbicidal compounds.

Fig. 4A, as well as 4B and 4C, presents various chairs 1 , especially customer chairs, which can be used in sets of furniture depicted in figs. 1A, 1 B and 2A in place of the customer chairs shown therein. These have been provided with vari ous antimicrobial coatings capable of eliminating 95% of selected pathogenic bac teria in the aforementioned tests ISO 22196 or J IS Z 22801.

Thus, fig. 4A reveals a pair of chairs 1 ; T and 1 ; 1”, which can be used for exam ple in the fixture assembly shown in fig. 2A in place of the customer chairs visible therein.

The chairs 1 ; 1¹, 1 ; 1² of a set of chairs 9; 92 appearing in fig. 4A are both metal framed customer chairs. The outwardly exposed surfaces of these customer chairs 1 ; 1¹, 1 ; 1² are again potential contact surfaces, which are provided with coatings comprising antimicrobial silver. Each customer chair 1 ; 1¹ and 1 ; 1² comprises a wood-framed seat panel 10 having its topside and side edges either provided with an antimicrobial plastic laminate coating 10c; 64. The fabrication of and the amount of silver contained in the antimicrobial laminate coating 10c; 64 (melamine lami nate or polyester laminate) for the seat panel 10 were similar to those presented in fig. 7C. Hence, the laminate coating’s topmost adjuvant-treated film contained sil ver 0,005-0,1 % by weight calculated from the weight of resin used for fabricating the topmost film layer.

The seat panel 10 has its underside generally painted, nor has the paint surface been treated with an antimicrobial silver compound since the seat panel’s 10 un derside is generally not regarded as a contact surface which would require treat ment with silver compounds.

From the seat panel 10 of both customer chairs 1 ; 1¹, 1 ; 1² rises upward a back support 1 1 with a metallic support frame 1 12, said support frame 1 12 having mounted thereon an upward-directed wooden backrest 113. The back support 11 has its upward-directed metal frame coated with an antimicrobial powder paint coating 61 a in a manner similar to that illustrated in fig. 7F for an aluminum- constructed leg 13 of the chair 1 , which is coated with an antimicrobial powder paint coating 61 ; 61 a. The amount of microbicidal silver was 0,005-0,1 % by weight calculated from the powder paint layer’s 61 a dry weight.

On the metallic support frame 1 12 of the back support 1 1 is mounted a plate-like wooden backrest 1 13 which can be fabricated from a compression-molded article, plywood or solid wood.

The first customer chair 1 ; 1¹ has each side of its backrest 1 13 coated with a plas tic laminate coating 1 1 c which has received an antimicrobial treatment. Each side of the backrest 1 13 is coated with a melamine resin-based plastic laminate coating 11 c. The plastic laminate coating on each side of the backrest 1 13 has a total thickness of about 0,4-0, 8 mm and the plastic laminate coating of each side has been supplemented with an antimicrobial silver compound in a manner similar to that illustrated in fig. 7C. The fabrication of and the amount of silver contained in the antimicrobial laminate coating 1 1 c; 64 (melamine laminate) were similar to those presented in fig. 7C: in this case, as well, the plastic laminate’s topmost sur face film 64¹, 64a was excluded completely and replaced by impregnating the topmost decorative paper 64², 64b twice with a melamine resin batch.

The silver-containing silver phosphate glass, wherein the silver phosphate glass has a general formula Ca3oNa20-xP5oAg_x, and x is 0,1-10, preferably 0,5-5, was only incorporated in resin used for the latter impregnation of decorative paper. This enabled formation directly on top of the decorative paper of a thin resin-containing surface film, which contained a silver compound. After treatment, the thin surface film of the topmost decorative paper 64b contained silver again about 0,005-0,1 % by weight calculated from the amount of resin incorporated in the topmost surface film.

All 4 legs of both chairs 1 ; 1¹ , 1 ; 1² are metal legs 13 (so-called tubular leg), which are coated with a powder paint coating 13d3. The powder paint coating 13d3 of each chair leg is formed as an antimicrobial powder paint coating 61 ; 61 a as ex plained in more detail later in connection with the description of fig. 7F. The pow der paint coating 61 ; 61 a is produced by spraying or otherwise applying powder paint onto each chair leg 13 for a uniform powder paint layer of about 100 pm, which develops, upon drying, a powder paint coating 61 a (powder paint film) of about 50-60 mih which contains some silver-containing, antimicrobial, carrier- bonded compound, such as zeolite-bonded silver or silver phosphate glass. Silver phosphate glass or silver-containing zeolite is admixed into the powder paint in such an amount that the dry paint film 61 a contains silver 0,005-0,1 % by weight calculated from the powder paint’s dry weight.

Such a microbicidal lacquer coating 62 eliminates, in the aforementioned test ISO 22196 or JIS Z 2801 , at least 95% of bacteria used in the test.

Fig. 3, on the other hand, illustrates a set of furniture present in a single space, such as in an office room, the pieces of furniture thereof being adapted for simul taneous use. This set of furniture includes a table 3 provided with a metal-coated circular tabletop 30. The tabletop rests on a floor by way of a metal-constructed leg post 35; 35a and a base included therein. The leg post 35; 35a can also be fabricated from solid wood and coated in a per se conventional manner with furni ture paint or lacquer. The paint coating of the leg post 35 is not generally provided with antimicrobial activity because, in normal situation, the leg post is not within touching distance from the user leaning against the tabletop.

In the embodiment of the invention, depicted in fig. 3, the tabletop 3 has on its top- and undersides a metal-coated tabletop 30. The tabletop 30 has its vertical edge 30b provided with a polymer rim 30d, which in this case is a polyester-based edge strip 30e. The metal-coated tabletop 30 has its polymer rim 30b rendered antimi crobial in such a way that the polyester resin making up the edge strip 30e has been supplemented, in the edge strip fabrication process, with carrier-bonded sil ver in such an amount that the edge strip, whose thickness is 0,5-4 mm, contains silver 0,005-0,1 % by weight calculated from the weight of polyester resin or ABS resin used for making the edge strip.

The seat panel 10 as well as the back support/backrest 1 1 , 1 13 of all customer chairs 1 ; 1 ¹— 1 ; 1⁴ appearing in fig. 3 are fabricated from wood. All exposed surfac es of the seat panel 10 and the backrest/back support 1 1 , 1 13 have been treated so as to possess antimicrobial activity, i.e. are capable of eliminating, in ISO 22196 or JIS Z 2801 test, at least 95% of bacteria used in the test. The back sup port 1 1 of chairs 1 ; 1², 1 ; 1³, and 1 ; 1⁴ consists of a continuous wood-framed backrest 1 13. Both the seat panels 10 and the back supports 1 1 are coated over front and rear sides thereof with a polyester resin- or melamine resin-based plastic laminate 1 1 ; 1 1 c and this plastic laminate has been supplemented, during fabrica tion, with silver phosphate glass having a general formula Ca3oNa20-xP5oAg_x, wherein X = 0,1-10, preferably 0,5-5, as described more closely in fig.7C. The thus obtained plastic laminate coating has a thickness of 0,4-1 ,4 mm and contains silver only in the topmost decorative paper. The decorative paper contains silver 0,005-0,1 % by weight calculated from the total weight of those polyester resin batches or melamine resin batches by which the decorative paper has been im pregnated.

On a vertical edge (rim) 105 of the seat panel as well as on a vertical edge (rim) 1 15 of the back support 1 1 c of each customer chair 1 ; 1 ¹— 1 ; 1⁴ is further produced a paint coating 105d, 1 15d with 1 -3 paint layers and the topmost paint layer is supplemented with carrier-bonded silver for example in the form of silver phos phate glass. The silver phosphate glass has a general formula Ca3oNa20-xP5oAg_x, wherein X = 0,1 -10, preferably 0,5-5, whereby the amount of silver in the topmost paint layer will be 0,005-0,1 % by weight calculated from the dry weight of the paint coating 105d, 1 15d, such as a lacquer coating. The topmost paint layer, when dry, has a thickness of 0,20-0,40 pm provided that the paint or lacquer has respective ly a dry weight of 20-40% by weight.

Fig. 7C reveals a typical antimicrobial plastic laminate 64, in the figure a melamine laminate 641 which can be, among others, a laminate coating 310c of the wooden tabletop 31 , a laminate coating of the wood material-constructed desk 5, a lami nate coating 1 1 c for the wood material-constructed backrest 1 1 of a chair 1 , or a laminate coating 10c for the wood material-constructed seat panel 10 of a chair 1 . The plastic laminate 64 appearing in the figure includes six films 64¹... 64⁶ pressed against each other by the application of heat. There can also be fewer films. These films 64¹... 64⁶ are denoted in the figure with reference numerals 64a, 64b, 64c, 64c, 64b. Of these there is denoted with reference numeral 64a a surface film, consisting for example of cellulose paper which has been impregnated with mela mine resin 60-80 g/m².

Denoted with reference numeral 64b is decorative paper which has been impreg nated with melamine resin 120-150 g/m². Denoted with reference numeral 64c is, in turn, base paper which has been impregnated with phenol resin 120-150 g/m². Instead of or in addition to melamine resin, the fabrication of a plastic laminate 64 can be carried out by using e.g. phenol resins as well as polyester resins. In terms of general manufacturing technique, regarding the plastic laminate 64, reference is here made to the per se known prior art, such as Koponen, H 1991 , Puutuotteiden jalostus ja kehitys 538 (Refinement and development of wood products), Otatieto Oy, Espoo. The plastic laminate 64 can be rendered antimicrobial in various ways: either only its topmost decorative paper 64², 64b, topmost decorative paper 64², 64b as well as topmost surface film 64¹, 64a, or all of its films 64¹... 64⁶ can be treated antimi- crobially. In addition, the topmost surface film 64¹, 64a may also be excluded and substituted for by impregnating the topmost decorative paper 64², 64b two times with resin and by incorporating the antimicrobial silver treatment in the latter resin batch used for impregnating the decorative paper. The amount of antimicrobial sil ver is in all treatments 0,005-0,1 % by weight calculated, however, only from those resin batches used for silver-treated films. The silver is added into the films while mixed within a suitable adjuvant.

Preferably, the silver is added in a bonded-to-carrier form, i.e. either as silver phosphate glass or as zeolite, into a film-forming resin, such as melamine resin, in the process of impregnating paper with resin. By selecting only a specific film/specific films 64¹... 64⁶ of the plastic laminate 64 to be rendered antimicrobial, there is achieved a highly cost-effective process applicable to large production rates.

In one preferred embodiment, silver was added into a plastic laminate 64 in the form of silver phosphate glass. The general formula of silver phosphate glass was Ca3oNa20-xP5oAg_x, wherein X = 0,1 -10, preferably 0,5-5. The thus fabricated, sil ver phosphate glass-treated plastic laminate 64 can be used as a laminate coat ing, among others, in a topside laminate coating 310c for the wood-framed tab letop 31 , as a topside laminate coating for the reception desk 5, as a laminate coating 1 1 c for the backrest 1 1 of a chair 1 or as laminate coating for the seat panel 10 of a chair 1 . The tabletop 31 surface and the reception desk 5 are usually only treated over the topside thereof, i.e. over the service side thereof, with silver phosphate glass.

Fig. 7G reveals schematically some end face area in the wooden tabletop 31 of a table 3, wherein the vertical plane passing by way of an edge 33 is transverse relative to a horizontal plane of the tabletop’s topside shown in fig. 7G. The tab letop 31 has its end face formed with an elongated antimicrobial polymer rim 33, 63 co-directional with a top edge 31 b of the tabletop. The polymer rim 33d can be either an edge casting 33f made of polyurethane or an edge strip 33e made of polyester or ABS polymer. The antimicrobial silver compound, such as the afore mentioned silver phosphate glass whose general formula is Ca3oNa2o-xP5oAg_x), wherein x = 0,1 -10, preferably x = 0,5-5, is added in the polymer rim manufactur- ing process into polyurethane resin (edge casting) or polyester resin (edge strip) making up the polymer rim 33d.

Figs. 5A and 5B each shows a plurality of antimicrobial fixture assemblies 8 sepa rated by space dividers (partitions).

Fig. 5A depicts, in a diagonal overhead view, an open-plan office with various fix ture assemblies 8; 8¹, 8; 8², 8; 8³ _’ 8; 8⁴... 8ⁿ defined by space dividers (partitions). The pieces of furniture included in each fixture assembly 8; 8¹, 8; 8², 8; 8³ _’ 8; 8⁴ etc. are intended for simultaneous use.

Described more closely hereinafter will be three fixture assemblies 8; 8¹, 8; 8² and 8; 8³ visible in the front area. Hence, the fixture assembly 8; 8¹, visible in the fore ground to the right, includes a table 3 provided with a metal-coated tabletop 30.

The metallic tabletop’s vertical edge 30b, which is bounded by top- and undersides of the tabletop, may be provided with a polymer rim 30d such as an edge strip 30e or an edge casting 30f. In case the tabletop is fabricated in its entirety from antimi crobial brass or from a copper alloy with at least 60% copper, the vertical edge 30b can be left untreated.

In the event that the table 3 has its vertical edge 30b provided with a polymer rim 30d, the latter is nevertheless rendered antimicrobial by supplementing, during the casting process, the polyurethane resin with a bonded-to-carrier silver compound in such an amount that the polymer rim, fabricated from polyurethane casting, has a thickness of 1-5 mm and contains silver 0,005-0,1 % by weight calculated from the weight of polyurethane resin used for casting said polymer rim.

The metal-coated table 3 may have its polymer rim 30d rendered antimicrobial al so in such a way that the polymer rim is an edge strip 30e which has been ren dered antimicrobial by supplementing, during an edge strip manufacturing pro cess, the edge strip-forming polyester resin or ABS resin with a silver compound in such an amount that the edge strip, which has a thickness of 0,5^f mm, contains silver 0,005-0,1 % by weight calculated from the weight of polyester resin or ABS resin used for making the edge strip.

Thus, with regard to the tabletop and base structure and antimicrobial treatment of tabletop, this metal-coated table 3 included in the fixture assembly 8; 8¹ is highly similar to that already illustrated earlier in fig. 3. On the other hand, with regard to preparation of an antimicrobial powder paint coating for a leg 35; 35a of this table 3, the thickness of a coating, and the amount of silver contained in a coating, ref erence is made to fig. 7F and its description.

Fig. 5A also reveals, in the foreground in the middle and to the left, two identical fixture assemblies 8; 8² as well as 8; 8³, consisting of an electric table 3 equipped with adjustment legs, as well as of an office chair 2. Both the office chair 2 and the electric table have a general structure and antimicrobial coatings similar to those explained earlier in connection with the description of figs. 2A and 2B.

Fig. 5B also depicts various fixture assemblies 8; 8¹ , 8; 8². . . 8; 8⁷ used in open- plan office. The fixture assemblies 8; 8². . . 8; 8⁷ comprise identical fixture assem blies, consisting of an electric table 3 equipped with adjustment legs, as well as of an office chair 2. Both the office chair 2 and the electric table have a general struc ture and antimicrobial coatings similar to those explained earlier in connection with the description of figs. 2A and 2B.

The electric table 3 has its tabletop, which is fabricated from furniture board, coat ed over its topside with a plastic laminate coating 310c and, in its manufacturing process, the plastic laminate coating 310c has been supplemented with bonded- to-carrier silver compounds in such an amount that the plastic laminate coating has been rendered antimicrobial, thereby achieving the antimicrobial activity de fined in the aforementioned standards ISO 22196 or J IS Z 2801 against selected pathogenic bacteria.

The underside plastic laminate coating (or backing paper) of the electric table 3 is generally not perceived as a contact surface (cf. description of coatings for the electric table of fig. 2A). In this case, as well, the vertical rim delimited by a top side of the electric table 3 was turned into a silver-containing antimicrobial polymer rim, with respect to whose silver content and manufacturing method reference is here made to fig. 7G as well as its description.

Fig. 6 illustrates two different fixture assemblies 8; 81 and 8; 82.

The first fixture assembly 8; 81 , visible in the foreground, comprises a reception desk 5 and two office chairs 2; 2¹ and 2; 2² in conjunction therewith.

The second fixture assembly 8; 8², visible in the background, comprises in turn a negotiation table 3, a sofa 7, and a customer chair 1 . With regard to furniture included in the fixture assembly 8; 8², the sofa 7 has a structure and a treatment to make it antimicrobial which are similar to what has been described above in connection with the fixture assembly 8; 81 of fig. 5B. The sofa 7 consists of a seat component and a backrest component, which, with the exception of sofa legs, are covered (upholstered) all over with fabric upholstery 66 which has received antimicrobial treatment. Likewise, the customer chair has been upholstered all over with fabric upholstery 66 which has received antimicrobial treatment. The sofa 7 has its antimicrobial fabric upholstery rendered microbicidal by incorporating therein silver-containing polyamide fibers or isothiazolidine com pounds or organofunctional silanes as reported more precisely e.g. in connection with the description of fig. 7B.

The negotiation table 3 includes a tabletop, which is fabricated from furniture board or solid wood and from the underside of which extend downward four table legs constructed from wood material. The tabletop may be covered with a laminate coating, preferably with a plastic laminate coating, as reported more closely in fig. 7C and its description. The plastic laminate’s topmost film (decorative paper + melamine resin) contains silver 0,005-0,1 % by weight calculated from the weight of melamine added into the topmost film.

The reception desk 5 comprises a base 55, on which rests a plate-like worktop 50 constructed predominantly from wood material. The worktop 50, in turn, comprises an upturned cover 50a of the worktop and an underside of the worktop, said un derside being directly adjoined by the wood material-constructed base 55 directed downward from the desk’s worktop. The base 55 has a wooden surface, which can be coated with a plastic laminate or a plastic film. All surfaces of the base 55 are not generally regarded as contact surfaces, but only a forward part of the base fac ing the customer. This part of the base is generally perceived as a contact surface and its plastic laminate coating (melamine resin-based) is treated to make antimi crobial as observed in connection with fig. 7C.

The worktop 50 has its surface proximal to the cover 50a provided with an antimi crobial coating, which can be a paint coating, a plastic laminate coating, or a plas tic film. Such an antimicrobial coating has been tested according to ISO 22196 or JIS Z 2801 and it eliminates at least 95% of selected bacteria used in the test.

The worktop 50 has its vertical edges 53 provided with a polymer rim, which can be an edge strip or an edge casting whose rendering antimicrobial has already been described earlier. Hence, in the event that the polymer rim is a polyester- based edge strip 33d, said edge strip is rendered antimicrobial in such a way that the edge strip-forming polyester resin is supplemented, in the edge strip manufac turing process, with bonded-to-carrier silver in such an amount that the edge strip, whose thickness is 0,5-4 mm, contains silver 0,005-0,1 % by weight calculated from the weight of polyester resin used for making the edge strip. Such an antimi crobial coating must again be tested in accordance with ISO 22196 or JIS Z 2801 and it is required to eliminate at least 95% of bacteria used in the test.

The polymer rim may also be a polyurethane-constructed edge casing, having a thickness of 1 -5 mm, and into the edge casting is admixed, during mold casting, bonded-to-carrier silver 0,005-0,1 % by weight calculated from the weight of polyu rethane resin (mainly polyol + isocyanate) used for making the edge casting.

In case the worktop 50 has its cover coated with a plastic laminate, preferably with a melamine laminate, it is provided with an antimicrobial silver compound in a manner similar to that described more closely in fig. 7C. In this case, the melamine laminate 641 constitutes a laminate coating for the wood material-constructed re ception desk 5. With regard to general manufacturing technique for plastic lami nate 64. reference is here made to the per se known prior art such as Koponen, H 1991 , Puutuotteiden jalostus ja kehitys 538 (Refinement and development of wood products), Otatieto Oy, Espoo. There are various ways of rendering the plastic laminate 64 antimicrobial as explained in fig. 7C. However, the amount of antimi crobial silver is in all treatments 0,005-0,1 % by weight calculated, however, only for silver-treated films. Preferably, the silver is added in a bonded-to-carrier form, i.e. either as silver phosphate glass or as zeolite, into the film-forming resin, such as into melamine resin, as the paper is impregnated with resin. In a preferred em bodiment of the invention, silver was added into the worktop’s plastic laminate in the form of silver phosphate glass. The general formula of silver phosphate glass was Ca3oNa20-xP5oAg_x, wherein X = 0,1 -10, preferably 0,5-5. The thus produced, silver phosphate glass-treated plastic laminate 64 can be used as a laminate coat ing in the laminate coating for the rest of the topside 50a of the worktop 50. The customer service desk 5 has its undersurface usually treated over its topside, i.e. its service side, with silver phosphate glass. The other side, i.e. the worktop’s un derside adjoining the base 55, is usually left without antimicrobial treatment. List of reference numerals

1 Chair, multiple legs

1 ¹ 1⁴ group of customer chairs

10 seat panel of the chair

10a textile upholstery

10a1 ,10a2, 10a3, 10a4 various textile upholsteries

10b wood veneer overlay

10c plastic laminate coating

10c1 melamine resin

10c2 polyester resin

10d paint coating

10d1 lacquer coating

10d2 wood paint coating

10d3 powder paint coating

105 edge, rim of the seat panel

105d wood paint coating

10e wooden surface

1 1 back support

110 wood-constructed support frame for the backrest 112 metal-constructed support frame for the backrest 113 backrest

11 a textile upholstery 11 b wood veneer overlay

1 1 c plastic laminate coating

11 d paint coating

11 d1 lacquer coating

11 d2 (wood) paint coating

11 d3 powder paint coating

115 edge, rim of the backrest

115d paint coating

13 chair leg, made of metal

130 chair legs, made of metal

13d paint coating

13d3 powder paint coating

14 armrest coupled with the chair leg

14a leg component

14b seat component

14c armrest component

15 chair leg, made of wood

150 wooden chair legs

15d wood paint coating

16 combined chair leg and armrest, made of wood 16a armrest component

16b leg component

17 wooden armrest 17d wood paint coating

2 office chair, leg post

20 seat panel of the office chair 20a textile upholstery

21 back support, backrest

21 a textile upholstery

22 neck support

22a textile upholstery

23 adjustment leg

27 armrest

27a support surface

27b support arm

28 base

29 adjusters

3 table

30 tabletop, metal surface 30a topside of the tabletop 301 metal coating

30b vertical edge of the tabletop 30d polymer rim

30e edge strip

30f edge casting

31 tabletop, wooden surface 31 a topside of the tabletop

310a paint coating

310b wood veneer overlay

310c plastic laminate coating 31 Od plastic film

33 vertical edge of the tabletop 33a paint surface, paint coating 33d polymer rim

33e edge strip

33f edge casting

31 b underside of the tabletop 320a paint surface

320b wood veneer overlay

320c plastic laminate coating 31 Od plastic film

34 table leg, made of wood 34a leg post

34b edge leg

35 table leg, made of metal 35a leg post

35b edge leg

35c leg with adjustment mechanism

4 keeper 41 cabinet

41 a door

41 b handle

41 c top

5 desk

50 worktop

50a cover

53 vertical edge

55 base

6 antimicrobially treated material 60 metal surface

61 paint coating

61 a powder paint coating

61 b wood paint coating

62 lacquer coating

62\ 62² layers/films of the lacquer coating

63 polymer rim

64 plastic laminate

64¹..64⁶ films of the plastic laminate 641 melamine laminate

64a surface film

64b decorative paper

64c base paper 65 plastic film

65a melamine film, self-adhesive

66 textile upholstery

66a silver bonded to polyamide fibers 66b silane derivative

66c isothiazolidine

67 injection molded component

68 brass surface

69 copper surface

7 sofa

8 Fixture assembly

81 ,82,82 fixture assemblies

9 group of chairs

91 row, line of chairs

92 pair of chairs

Claims

1. An antimicrobial wood material-based piece of furniture (1 , 2, 3, 5) with a plastic laminate coating, comprising a plastic laminate coating placed on a furniture sur face, preferably on a contact surface, and having a thickness of 0,4-1 ,4 mm, and said laminate coating comprising one or more overlapping films (64¹... 64⁶), each of said films consisting of paper impregnated with resin, especially melamine resin or polyester resin, characterized in that the piece of furniture has its plastic laminate coating provided with antimicro bial activity at least against S.aureus and E.coli, whereby the plastic laminate coat- ing, when tested according to standards ISO 22196 or JIS Z 2801 , has antimicro bial activity which eliminates at least 95% of bacteria used in the test, the antimicrobial activity of the piece of furniture’s plastic laminate coating has been achieved by impregnating one or more films of the plastic laminate coat ing with at least one resin batch which has been supplemented with a silver- containing adjuvant in such an amount that each silver-containing film of the lami nate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin incorporated in each silver-containing film, and the plastic laminate coating’s antimicrobial activity has been achieved by im pregnating paper, comprising a topmost film of the plastic laminate coating, espe- daily decorative paper, with several resin batches, whereby the final resin batch has been supplemented with a silver-containing adjuvant in such an amount that the laminate coating’s topmost film contains silver 0,005-0,1 % by weight calculat ed from the total weight of resin batches contained in said topmost film.

2. An antimicrobial wood material-based piece of furniture according to claim 1 , characterized in that the plastic laminate coating’s antimicrobial activity has been achieved by impregnating at least a topmost film layer of the plastic laminate coat ing with at least one resin batch into which has been added a silver-containing ad juvant in such an amount that the resin batch contains silver (Ag) 0,005-0, 1 %by weight provided, however, that the laminate coating’s topmost film contains silver 0,005-0,1 % by weight calculated from the total weight of resin contained in said film.

3. An antimicrobial wood material-based piece of furniture according to claim 1 , characterized in that the plastic laminate coating’s topmost film has been formed with a gradient containing antibacterial silver (Ag), wherein the amount of silver in- creases when proceeding in the paper, especially decorative paper, from interior to surface layer, by impregnating the topmost film-forming paper, especially deco rative paper, with two resin batches in such a way that into the final resin batch has been added a silver-containing adjuvant in such an amount that the laminate coating’s topmost film contains silver 0,005-0,1 % by weight calculated from the to tal weight of resin batches used for making said film.

4. An antimicrobial wood material-based piece of furniture according to claim 3, characterized in that the plastic laminate coating’s antimicrobial activity has been achieved by impregnating the plastic laminate coating’s decorative paper with two successive resin batches, such as polyester or melamine resin batches, whereby only the final resin batch has been supplemented with a silver-containing adjuvant in such an amount that the laminate coating’s topmost film contains silver 0,005- 0,1 % by weight calculated from the total weight of resin batches contained in said film.

5. An antimicrobial wood material-based piece of furniture (1 , 2, 3, 5) according to claim 1 , said piece of furniture being a table (3) with a wood material- constructed tabletop, said wood material-constructed tabletop having its underside adjoined by one or more wooden table legs or metal legs, the wood material- constructed tabletop having its topside provided with a plastic laminate coating with a thickness of 0,4-1 ,4 mm, and said laminate coating comprising one or more overlapping films (64¹... 64⁶), each of said films consisting of paper impregnated with resin, especially with melamine resin or polyester resin, characterized in that the tabletop has its plastic laminate coating provided with antimicrobial activi ty at least against S. aureus and E.coli, whereby the plastic laminate coating, when tested according to standards ISO 22196 or J IS Z 2801 , has antimicrobial activity which eliminates at least 95% of bacteria used in the test, the antimicrobial activity of the tabletop’s plastic laminate coating has been achieved by impregnating one or more films of the plastic laminate coating with at least one resin batch which has been supplemented with a silver-containing adju vant in such an amount that each silver-containing film of the laminate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin con tained in said film.

6. An antimicrobial wood material-based table (3) according to claim 5, wherein at least one vertical edge (30b, 33) (A12, A22) of the wood material-constructed tabletop is further provided with a polymer rim (33d, 63) which has been adapted to have antimicrobial activity at least against S. aureus and E.coli by supplementing the polymer rim with a silver-containing adjuvant in such a way that the polymer rim, when tested according to standards ISO 22196 or JIS Z 2801 , has antimicro bial activity which eliminates at least 95% of bacteria used in the test, characterized in that the polymer rim is an elongated edge strip (33e), which is constructed from polyester-based or acrylobutadiene styrene-based resin, has a thickness of 0,5-4 mm, and contains silver (Ag) 0,005-0,1 % by weight calculated from the total weight of polyester- based or acrylobutadiene styrene-based resin incorporated in the edge strip (33e) or an elongated polyurethane-based polymer casting (33f) with a thickness of 1 -5 mm, and said polymer casting containing silver (Ag) 0,005-0,1 % by weight calculated from the total weight of polyurethane-based resin (polyol + polyisocya nate) incorporated in said polymer casting.

7. An antimicrobial wood material-based table (3) according to claim 5 or 6, characterized in that the undersurface of a wood material-constructed tabletop (30, 31 ) is also provided with a plastic laminate coating (310c, 64) having a thick ness of 0,4-1 ,4 mm, and said laminate coating comprising one or more overlap ping films (64¹... 64⁶), each of said films consisting of paper impregnated with res in, especially with melamine resin or polyester resin, characterized in that the tabletop has the plastic laminate coating of its undersurface provided with antimicrobial activity at least against S.aureus and E.coli, whereby the plastic lam inate coating, when tested according to standards ISO 22196 or JIS Z 2801 , has antimicrobial activity which eliminates at least 95% of bacteria used in the test, the antimicrobial activity of the plastic laminate coating of the tabletop’s un dersurface has been achieved by impregnating one or more films of the plastic laminate coating with at least one resin batch which has been supplemented with a silver-containing adjuvant in such an amount that the silver batch contains silver in such an amount that each silver-containing film of the laminate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin contained in said film.

8. An antimicrobial wood material-based table (3) according to claim 7, characterized in that the wood material-constructed tabletop (31 ) has its top- and under- surface provided with a polyester resin- or melamine resin-constructed plastic lam inate coating which has been adapted to have antimicrobial activity in a manner defined in claim 8.

9. An antimicrobial wood material-based table (3) according to claim 5 or 6, characterized in that the wood material-constructed tabletop has its undersurface further provided with an adhesive plastic film or backing paper, which has been adapted to have antimicrobial activity at least against S.aureus and E.coli by sup plementing the plastic film with a silver-containing adjuvant so as to provide the plastic film or backing paper with antimicrobial activity which, when tested accord ing to standards ISO 22196 or JIS Z 2801 , eliminates at least 95% of bacteria used in the test, whereby the plastic film or backing paper has its topmost layer comprising paper which is impregnated with polyester, melamine, urea or phenol resin supplemented with an adjuvant comprising bonded-to-carrier silver 0.005 - 0,1 % by weight calculated from the weight of polyester, melamine, urea or phenol resin added into the decorative paper.

10. An antimicrobial wood material-based table (3) according to claim 5 or 9, characterized in that the decorative paper of the tabletop’s plastic laminate is im pregnated with polyester, melamine, urea or phenol resin, which contains 0,005- 0,10% by weight bonded-to-carrier silver calculated from the amount of said poly ester, melamine, urea or phenol resin that has been added into the decorative pa per.

1 1. An antimicrobial wood material-based piece of furniture according to claim 1 , said piece of furniture being an antimicrobial wood-framed chair, which has a top side of its seat panel or its backrest, especially the backrest of its back support, coated with a plastic laminate coating, said laminate having a thickness of 0,4-1 ,4 mm and said laminate comprising one or more overlapping films (64¹... 64⁶), each of said films consisting of resin-impregnated paper, characterized in that the seat panel and/or the backrest has its plastic laminate coating provided with antimicrobial activity at least against S.aureus and E.coli, whereby the plastic laminate coating, when tested according to standards ISO 22196 or JIS Z 2801 , has antimicrobial activity which eliminates at least 95% of bacteria used in the test, the antimicrobial activity of the seat panel’s and/or the backrest’s plastic lam inate coating has been achieved by impregnating one or more films of the plastic laminate coating with at least one resin batch which has been supplemented with a silver-containing adjuvant in such an amount that each silver-containing film of the laminate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin contained in said film.

12. Antimicrobial wood-framed chair (1 , 2) according to claim 1 1 , which includes a wood-framed seat panel (10, 20) adjoined by a back support (1 1 , 21 ) directed upward from the seat panel (10, 20), said back support consisting of either a backrest (1 13, 21 ) or a wooden, plastic or metallic support frame (110, 1 12) on which is supported the wood-surfaced backrest (113), and said wood-framed seat panel (10, 20) of the chair is further adjoined by one or more downward-directed chair legs (15, 13) coupled underneath the seat panel, said chair (1 , 2) having a topside of the seat panel provided with a plastic laminate coating (10c) adapted to have antimicrobial activity in a manner defined in claim 9.

13. An antimicrobial wood material-based chair (1 , 2) according to claim 1 1 or 12, characterized in that the legs of a chair (1 ) or an office chair (2), and/or a topside and/or side surfaces of armrests (14, 27) coupled with the back support, are also provided with a plastic laminate coating (64), especially a polymer or melamine laminate coating, having a thickness of 0,4 -1 ,4 mm and comprising one or more overlapping films (64¹... 64⁶), each of said films consisting of resin-impregnated paper, whereby the antimicrobial activity of the seat panel’s and/or the backrest’s plastic lam inate coating has been achieved by impregnating one or more films of the plastic laminate coating with at least one resin batch which has been supplemented with a silver-containing adjuvant in such an amount that each silver-containing film of the laminate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin contained in said film.

14. An antimicrobial wood material-based chair (1 , 2) according to claim 13, characterized in that the top and/or side faces of the armrests’ wooden surfaces are provided with a plastic laminate, which is mainly constructed from polyester or melamine resin and has a thickness of 0,4-1 ,4 mm, and which contains silver (Ag) 0,005-0,1 % by weight calculated from the weight of resin contained in the silver- treated laminate film, and in which the silver is predominantly contained in the topmost decorative paper that has been treated with the silver compound- containing resin.

15. An antimicrobial wood material-based piece of furniture (1 , 2, 3, 5) according to claim 1 , said piece of furniture being a desk (5), such as a reception desk, which has a predominantly wood material-constructed plate-like worktop (50), comprising an upturned cover (50a) of the worktop and an underside of the worktop, said un derside being directly adjoined by a wood material-constructed base (55) directed downward from the desk’s worktop, whereby the desk (5) has surface of its work top (50) proximal to the cover (50a) provided with a plastic laminate coating adapted to have antimicrobial activity, said plastic laminate coating having a thick ness of 0,4-1 ,4 mm and said laminate coating comprising one or more overlap ping films (64¹... 64⁶), each of said films consisting of resin-impregnated paper, characterized in that the desk (5) has its plastic laminate coating provided with antimicrobial activi ty at least against S.aureus and E.coli, whereby the plastic laminate coating, when tested according to standards ISO 22196 or JIS Z 2801 , has antimicrobial activity which eliminates at least 95% of bacteria used in the test, the antimicrobial activity of the desk’s (5) plastic laminate coating has been achieved by impregnating one or more films of the plastic laminate coating with at least one resin batch which has been supplemented with a silver-containing adju vant in such an amount that each silver-containing film of the laminate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin con tained in said film.

16. An antimicrobial wood material-based desk (5) according to claim 15, where in at least one vertical edge (53) of the worktop (50) is further provided with a pol ymer rim, which is adapted to have antimicrobial activity at least against S.aureus and E.coli, whereby the polymer rim, when tested according to standards ISO 22196 or JIS Z 2801 , has antimicrobial activity which eliminates at least 95% of bacteria used in the test, characterized in that the polymer rim is an elongated edge strip (33e), which is constructed from polyester-based or acrylobutadiene styrene-based resin, has a thickness of 0,5-4 mm, and contains silver (Ag) 0,005-0,1% by weight calculated from the total weight of polyester- based or acrylobutadiene styrene-based resin incorporated in the edge strip (33e) or an elongated polyurethane-based polymer casting (33f) with a thickness of 1-5 mm, and said polymer casting containing silver (Ag) 0,005-0,1 % by weight calculated from the total weight of polyurethane-based resin (polyol + polyisocya nate) incorporated in said polymer casting, an elongated polyester polymer-based or ABS polymer-based edge strip (33e), which has a thickness of 0,5-4 mm and which contains silver (Ag) 0,005- 0,1 % by weight calculated from the total weight of polyester or ABS resin used for making the edge strip (33e) or an elongated polyurethane-based polymer casting (33f) with a thickness of 0,5-5 mm, preferably 1-5 mm, and said polymer casting containing silver (Ag) 0,005-0,1 % by weight calculated from the total weight of polyurethane resin (poly ol + isocyanate) used for said polyurethane casting.

17. An antimicrobial wood material-based desk (5) according to claim 15 or 16, characterized in that the wood material-constructed base (55) adjoining the underside of said worktop is also coated with a plastic laminate (1 1 c, 64), which is provided with an timicrobial activity at least against S.aureus and E.coli, whereby the laminate coat ing, when tested according to standards ISO 22196 or JIS Z 2801 , has antimicro bial activity which eliminates at least 95% of bacteria used in the test, whereby said laminate coating has a thickness of 0,4-1 ,4 mm and said laminate coat ing comprises one or more overlapping films (64¹... 64⁶), each of said films con sisting of resin-impregnated paper, and the antimicrobial activity of the plastic laminate coating has been achieved by impregnating one or more films of the plastic laminate coating with at least one resin batch which has been supplemented with a silver-containing adjuvant in such an amount that each silver-containing film of the laminate coating contains silver 0,005-0,1 % by weight calculated from the total amount of resin contained in said film.

18. An antimicrobial wood material-based piece of furniture according to any of the preceding claims, characterized in that the silver-containing adjuvant, which has been added into a resin batch (64c) of the plastic laminate coating or into pol ymer (63) making up the polymer rim, especially an edge casting or edge strip, comprises silver bonded to a solid carrier compound, such as silver bonded to phosphate glass or zeolite.

19. An antimicrobial wood material-based piece of furniture according to claim 18, characterized in that the adjuvant comprises silver phosphate glass, having a general formula Ca3oNa2o-xP5oAg_x, wherein x = 0,1-10, preferably x = 0,5-5.

20. An antimicrobial wood material-based piece of furniture according to claim 1 , characterized in that the tabletop (31 ) has its core constructed from furniture board such as chipboard, plywood or fiberboard, especially mdf board.

21. A method for coating a piece of furniture with an antimicrobial plastic lami nate coating, characterized in that the method comprises the following steps of: manufacturing a plastic laminate coating (310c, 64), said plastic laminate having a thickness of 0,4-1 ,4 mm, by gluing on top of each other several films (64¹... 64⁶), each of said films consisting of paper impregnated with resin, especially melamine resin or polyester resin, whereby one or more films of the plastic laminate coating has been impregnated, during manufacture of the plastic laminate coating, with at least one resin batch which has been supplemented with a silver-containing adju vant in such an amount that each silver-containing film of the laminate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin con tained in said film, whereby each film, which has been treated with silver as de scribed above, has antimicrobial activity at least against S.aureus and E.coli, the selected laminate coating, when tested according to standards ISO 22196 or J IS Z 2801 , having antimicrobial activity which eliminates at least 95% of bacteria used in the test,

- coating a surface of the piece of furniture with a plastic laminate coating.

22. A method according to claim 21 , characterized in that only the topmost dec orative paper is treated with polyester or melamine resin which contains a silver compound.

23. A method according to claim 21 or 22, characterized in that the silver is add ed in the form of silver which is bonded to a solid carrier compound such as phos phate glass or zeolite.

24. A method according to claim 21 , characterized in that the silver is added in the form of silver phosphate glass which has a general formula Ca3oNa2o-xP5oAg_x), wherein x = 0,1-10, preferably x = 0,5-5.

25. A method according to claim 21 , characterized in that the plastic laminate is a low pressure laminate, wherein the paper layers are first impregnated with resin and thereafter the overlapping paper layers are pressed to each other with a com pression pressure of 4.0 Mpa.

26. An antimicrobial plastic laminate coating (310c, 64). which is applicable onto a surface of a wood material-based piece of furniture in a manner defined in claim 21 , said plastic laminate coating having been provided with antimicrobial activity at least against S.aureus and E.coli in such a way that the plastic laminate coating, when tested according to standards ISO 22196 or JIS Z 2801 , has antimicrobial activity which eliminates at least 95% of bacteria used in the test, and said plastic laminate coating has a thickness of 0,4-1 ,4 mm and has been manufactured by gluing on top of each other several films (64¹... 64⁶), each of said films consisting of resin-impregnated paper, characterized in that the plastic laminate coating has been provided with said antimicrobial activity by impregnating one or more films of the plastic laminate coating with at least one resin batch which has been supplemented with a silver-containing adjuvant in such an amount that each silver-containing film of the laminate coating contains silver 0,005-0,1 % by weight calculated from the total weight of resin contained in said film.

27. A plastic laminate coating according to claim 26, wherein the plastic laminate coating is a low pressure laminate in which the paper layers have been first im pregnated with resin and thereafter the overlapping paper layers have been pressed to each other with a compression pressure of 4.0 Mpa.