Field of the invention

The present invention relates generally to the field of paper and similar products and articles, and to the production thereof, and more particularly it relates to a new and innovative process for producing a new and special type of wallpaper, using, as a base material for forming a respective decorative layer, PLA, i.e. the polymer of lactic acid or PolyLActide, ecological and biocompatible, thus able to meet and satisfy the current and pressing requirements and expectations of the market and of the modem economy toward ecological products involving an improved environmental sustainability and a reduced pollution, as well as a corresponding production of biodegradable and easily disposable waste, compared to conventional wallpapers currently in use in the market, which as is known are a source of not negligible environmental pollution.

The present invention also relates to a corresponding ecological and biocompatible wallpaper, with reduced environmental impact, produced or suitable to be produced by the above process using PLA as a base material for making a decorative layer of the wallpaper, and a plant configured to implement such a process,

Reference and incorporation of a previous patent application for invention in the name of the Applicant

For completeness of information, it is pointed out that, in the same technical field of the present invention, the Applicant is already the owner of a previous Italian patent application for invention, filed on August 4, 2021 with No. 102021000021197, having the following title "ECOLOGICAL AND BIOCOMPATIBLE WALLPAPER AND CORRESPONDING PROCESS AND PLANT FOR THE PRODUCTION OF WALLPAPER WITH ECOLOGICAL AND BIOCOMPATIBLE MATERIAL", to confirm the constant commitment and activity of the same Applicant to search for solutions suitable to meet the present ecological and environmental requirements in the field of wallpaper.

In particular, the ecological and biocompatible wallpaper object of the present invention is an interesting evolution and a significant improvement of that one, also ecological and biocompatible, which is described by the above-mentioned Italian patent application No. 102021000021197, and in particular it appears suitable to remedy some limits and drawbacks arising during experimental tests on this wallpaper, corresponding to and disclosed by this Italian patent application for invention N. 102021000021197, in addition to involve a more efficient production process for its production in industrial form.

It follows that to this previous Italian patent application No. 102021000021197, in the name of the same Applicant, it is possible to make direct reference for any further information and any additional data which can be useful for integrating and clarifying the content of the present patent application for invention.

Moreover, always in order to allow a complete and correct appreciation of the characteristics of the present invention, the entire content of this previous Italian patent application for invention N. 102021000021197, owned by the Applicant, including the accompanying drawings, is incorporated in its entirety in the present patent application for invention.

For the sake of clarity, however, those parts already contained in the above- mentioned patent application for invention will be again disclosed and included in the following description, whereas they will be deemed useful for understanding and appreciating in the most complete and exhaustive way the features and characteristics of the ecological and biocompatible wallpaper of the present invention, although this will involve the repetition of concepts and information already presented.

Background of the invention and state of the prior art

As known, wallpaper has been widely used for a long time to cover and decorate walls and environments of various kinds in place of plaster and other forms of decoration and coating, and it is offered on the market in various forms, typologies and decorative configurations.

The wallpaper usually and essentially consists of a base support sheet which supports and on which a decorative layer exhibiting a decoration, usually digitally printed on the decorative layer, is formed.

Although wallpaper has been known and applied for a long time successfully in a multiplicity of various applications and has consequently been the subject of continuous evolutions and improvements, in line with the evolution and progress of the paper industry and technology, it is not to be considered free from limits and drawbacks, so as to be susceptible to further developments and improvements.

In particular, from what is apparent from the prior art, wallpaper which is currently offered and available in the market often does not appear to be capable of fully satisfying the modem needs and expectations of civil society, to which reference has been made first, reflected also in the current trends of the economy, as is clear to all, toward non-polluting and eco-sustainable products, suitable to be easily disposed of, and therefore having an environmental impact as low as possible.

In fact, very often the present wallpaper is made of materials, such as synthetic resins, others, which are not biodegradable, so as to imply a not negligible problem of environmental pollution at the time of their disposal, in particular when the wallpaper is removed from the wall on which it was applied.

It is true that in the prior art some attempts have been made to make wallpaper biocompatible and eco-sustainable, so as to meet and satisfy the emerging demands and needs of the market.

In this regard, there are mentioned in particular the patents of the Korean company LG HAUSYS LTD, which propose some solutions and embodiments of ecological and biodegradable wallpaper.

In particular, these ecological and biocompatible wallpaper papers developed by LG HAUSYS LTD provide for the use of the PLA or polymer of lactic acid or polylactide, which, as it is known, is a biodegradable plastic material, in the composition of the decorative layer which is formed by lamination on the support sheet.

However, also the ecological and biocompatible solutions and wallpaper proposed by these patents of LG HAUSYS LTD are not free from limits and drawbacks, in particular related to the formation by lamination of the decorative layer on the support sheet, and in any case they leave room for further developments and improvements, always in the direction of making the wallpaper environmentally sustainable and biocompatible.

More specifically, for the sake of completeness of information, the patents KR 2019 0043954, in the name of LG HAUSYS LTD, and EP 1 837 363 A1 , are cited in the background prior art of the present invention, wherein the first patent relates to an embossed light wallpaper, and the second patent to the manufacture of a sheet, usable for various applications including wallpaper, made of biodegradable material.

However, also the embodiments and solutions proposed by these two patents are not free from limits and drawbacks, other than exhibiting a composition and being produced by a production process substantially different from those of the wallpaper object of the present invention.

Patent WO 2015/170875 A1 is also mentioned, again in the name of LG HAUSYS LTD.

In particular, this patent describes a wallpaper that is produced with a production process that uses a resin mixture of PLA and PHA, or PolyHydroxyAlkanoate, wherein this resin mixture is mixed with a inorganic material acting as filler, a plasticizer and further additives in a kneader mixer or Banbury-type mixer, in order to prepare a compound which is heated and then passed through a calendering roll to form a layer or sheet of resin, which is finally bonded to a basic carrier sheet, thus forming the wallpaper.

However, compared to the wallpaper and the respective production process, known from this patent WO 2015/170875 A1 , the ecological and biocompatible wallpaper of the present invention and the respective production process exhibit numerous differences, described in detail in the following, which in turn imply a series of relevant and advantageous effects, clearly appreciated and recognized by the technicians of the sector, such as a greater consistency, compactness and solidity of the wallpaper produced.

In particular, in the process of the invention the resin layer is spread on the base support sheet so as to form the wallpaper, whereby the resin layer is formed directly by spreading on the support sheet in order to produce the wallpaper.

Instead, very differently, in the process known from this patent WO 2015/170875 A1 for the production of wallpaper, the PLA and PHA resin layer is formed by calendering and then mechanically joined by pressure to the base support sheet so as to form the wallpaper.

Finally, for completeness, the patent KR 2013 0106010 is cited, also in the name of LG HAUSYS TD, which describes a wallpaper, composed of several layers and produced by lamination, having a layer made of a PLA resin and ATBC (AcetylTriButylCitrate), as a biodegradable plasticizer.

Even in this case, however, the points of difference and the corresponding advantages of the ecological and biocompatible wallpaper of the invention compared to that described by this patent KR 2013 0106010 are relevant and not obvious.

Therefore, in the context as illustrated above and of the various problems, posed in this context, apparently unresolved or at least solved in a not entirely satisfactory manner, the inventor of the present invention has perceived that it was possible to go beyond the prior art, i.e. to improve the conventional wallpaper, currently known and in use, so as to enable them to meet fully and not only partially the current market expectations and in general those of the economy to have products that are easily disposed of and are increasingly less polluting, that is, more ecological and more compatible with the environment.

Objects and summary of the invention

It follows that a first object of the present invention is to propose and realize a new type of wallpaper which, while maintaining the same performances of the current wallpaper or even improving them as regards the decorative possibilities, is also able to meet and satisfy the current needs and demands of civil society towards ecological products, easily disposable and non-polluting, therefore in line with the current economic and market trend to promote and welcome the development and availability of new ecological and biodegradable products, i.e. with the minimum environmental impact or in any case as low as possible.

A second object, however linked to the previous one, of the present invention is also to develop a new and innovative process for producing ecological and biocompatible wallpaper, that is suitable for meeting the actual environmental requirements, in a simple way and at a competitive industrial cost, compared with that of conventional wallpaper, preferably using the same plants and the same machines, at the most only slightly modified, now used to produce a typical conventional wallpaper.

Moreover, a third object is also to propose and realize a new improved wallpaper, ecological and biocompatible, which in particular is such as to remedy some drawbacks experienced experimentally, such as a rather expensive production process, with respect to that, also ecological and biocompatible, disclosed by the Italian Patent Application No. 102021000021197, in the name of the same Applicant.

The above objects can be considered fully achieved by the process for producing wallpaper, ecological and biocompatible, as recited by the main independent claim 1 , the ecological and biocompatible wallpaper, as defined by independent claim 7, and by the implant, for producing ecological and biocompatible wallpaper, corresponding to independent claim 10.

Specifically and as described in detail hereinafter, the process, provided by the present invention, for producing ecological and biocompatible wallpaper comprises the following steps: a preparation step for preparing a biodegradable material suitable to be spread on a support sheet, wherein said preparation step in turn comprises: a solubilization step for solubilizing lactic acid polymer or PLA, that is PolyLActide or PolyLActic acid, provided in granular form, in ethyl acetate so as to obtain a medium viscous resin; a plasticizing step for plasticizing the PLA resin with a biodegradable plasticizer, consisting of ATBC (AcetilTriButilCitrate), so as to obtain a homogeneous resin of biodegradable material; and a charging step for adding bio-rice starch, i.e. starch of biological rice, and pulverized glass inorganic fillers in the resin of biodegradable material to act as fillers within the resin of biodegradable material; a coating step for coating the resin of biodegradable material on the support sheet, in particular consisting of a sheet of paper or a sheet of non-woven fabric, so as to form a decorative layer on said support sheet; an evaporation step to evaporate the ethyl acetate present in the decorative layer spread on the support sheet so as to render the decorative layer embossable; and an embossing step for embossing, after the evaporation step, the decorative layer formed on the support sheet, so as to obtain the ecological and biocompatible wallpaper.

According to another aspect, the invention also relates to a wallpaper, ecological and biocompatible, produced or producible by the above-mentioned production process.

Particular embodiments of the process for producing wallpaper, ecological and biocompatible, according to the invention, of the corresponding wallpaper produced or producible by such process, and of the corresponding plant for producing wallpaper with ecological and biocompatible material are further defined by the dependent claims.

Advantages of the invention

As it will be apparent from the following description, the new process for the production of ecological and biocompatible wallpaper, according to the present invention, and the corresponding ecological and biocompatible wallpaper, produced or producible by such process offer a series of relevant and unique advantages, some of which have already been previously announced, among which the following are mentioned purely by way of example: full compatibility and compliance of the new wallpaper with the ecological and environmental sustainability requirements, which have become increasingly pressing and no longer avoidable, both from civil society and from the market and the modem economy; total biodegradability, so as not to leave harmful residues in the environment, when the wallpaper, after use is removed from the wall on which it was applied and is subsequently disposed of; durability not unlike that of a conventional, non-ecological wallpaper; adaptability to specific and particular applications which is not different from that of the current conventional wallpaper; a cost of manufacture and production which is limited and not different from that of conventional wallpaper; the possibility of producing the new wallpaper with the same plants and the same machines currently used to produce a conventional, non-ecological wallpaper; decorative capacity and possibilities of the wallpaper of the invention equal to or greater than those of conventional, non-ecological wallpapers; possibility of using, for the digital printing of the decoration on the surface of the wallpaper of the invention, the same digital printing technologies and apparatuses already used to print the decorations on conventional non-ecological wallpapers; total compliance, of the wallpaper, ecological and biocompatible, of the invention, with the regulations and certifications actually in force.

Brief description of the drawings

These and other objects, features and advantages of the present invention will become apparent from the following description of a preferred embodiment thereof, given purely by way of non-limiting example with reference to the attached drawings, in which:

Fig. 1 , divided into sections (a) and (b), shows schematically in section, as indicated by arrows, and in plan view, with some areas removed, an ecological and biocompatible wallpaper produced by the process according to the present invention;

Fig. 2, divided into sections (a)-(e), is a series of photographic images showing, at sections (a)-(c), some samples, in the form of rolls, of the ecological and biocompatible wallpaper of Fig. 1 of the invention, and, at sections (d)-(e), a sample of the wallpaper on which a specific decoration has been digitally printed;

Fig. 3 is an operative block flow chart illustrating a preferred embodiment of a process according to the invention for producing the ecological and biocompatible wallpaper of Figs. 1 and 2;

Fig. 4 divided into sections (a) and (b), shows laterally and in plan a plant implementing the process of Fig. 3 for producing the ecological and biocompatible wallpaper of the invention of Figs. 1 and 2; and

Fig. 5 is a technical sheet illustrating the characteristics of lactic acid polymer or PLA (PolyLActide or PolyLActic acid), in granular form, as offered on the market by a respective generic supplier, used to produce wallpaper, of the invention, ecological and biocompatible.

For the sake of completeness, it should be noted that, in the following description of the invention, the reference to a given embodiment and application thereof does not exclude that a particular configuration, structure and characteristic, structural or operative, described in connection with this particular embodiment and application can be included and also be part of other embodiments and applications of the same invention, in which for reasons of synthesis it has not been described.

It follows that particular configurations, structures, steps, characteristics, either structural or functional, of the invention, can be combined in any suitable and coherent way in one or more embodiments and applications still falling within the scope and area of the same invention.

It should also be noted that the reference numbers used only meet convenience requirements and therefore do not in any way define the scope of the embodiments and applications, which will be described hereinafter, of the invention.

It is also pointed out that, in the following description, terms such as "biocompatible", "ecological", "biodegradable", "bio-sustainable", "eco-sustainable", "eco-friendly", and others similar, should be interpreted as synonyms and having a similar meaning, consistent and in line with the general teaching of the present invention aimed at meeting and satisfying the ecological and environmental requirements increasingly perceived by civil society and therefore reflected by modem industry.

Description of a preferred embodiment of the process of the invention for producing ecological and biocompatible wallpaper, of the corresponding ecological and , and of a plant implementing the same process

As already specified, the present patent application for invention refers directly to and incorporates the content of the previous Italian patent application No. 102021000021197, in the ownership of the Applicant, since it relates to an interesting evolution and an advantageous improvement, as result of the most recent research and experimentation activity carried out by the same Applicant, of the wallpaper, ecological and biocompatible, disclosed and protected by this previous patent application for invention.

This makes it possible to simplify, at least in some points, the description of the present application for invention, avoiding to describe in detail the characteristics and parts of the ecological and biocompatible wallpaper, already clearly described in the above-mentioned Italian patent application No. 102021000021197.

However, for reasons of clarity, there will be repeated and newly described hereinafter those parts of the description, although already contained in the above patent application No. 102021000021197, which are able to fully frame and describe in a clear and precise manner the wallpaper, ecological and biocompatible, object of the present patent application for invention.

Moreover, always for reasons of clarity, the same reference numerals, already used in this previous patent application for invention No. 102021000021197, in the name of the Applicant, will be kept in the following description in order to indicate the corresponding parts or the like, of course by adding or modifying the reference numerals where necessary to describe the new parts and characteristics which differentiate the wallpaper, ecological and biocompatible, object of the present patent application for invention, and the respective production process, with respect to the wallpaper, also ecological and biocompatible, described by the previous patent application No. 102021000021197.

With reference to the drawings, and in particular to Fig. 1 , a wallpaper, ecological and biocompatible, according to the present invention, is generally indicated with 10 and consists of: an ecological and biocompatible supporting or support sheet, indicated with 11 , in particular consisting of a coated paper sheet or a biodegradable non-woven fabric sheet; and a decorative, ecological and biocompatible layer, indicated with 12, formed by coating or spreading on the support sheet 11 , as described in detail hereinafter, wherein this decorative layer 12 is provided to be digitally printed on its surface, so as to exhibit a decoration.

The flowchart of Figure 3 in turn illustrates a process, according to the invention, indicated as a whole with 100, for producing and manufacturing the wallpaper 10 of the invention, ecological and biocompatible.

In detail, according to a salient feature of the present invention, the process 100 comprises the following steps: a preparation step, indicated with 101 , for preparing a material, indicated with M, biodegradable and spreadable on the support sheet 11 , wherein said preparation step 101 in turn comprises: a solubilization step, indicated with 101-1 , for solubilizing lactic acid polymer or PLA, i.e. PolyLActide or PolyLActic acid, provided in granular form, in ethyl acetate so as to obtain a medium viscous resin of PLA; and a plasticization step, indicated with 101-2, for plasticizing the resin of PLA with a biodegradable plasticizer, consisting in particular and preferably but not exclusively of ATBC, i.e. AcetylTriButylCitrate, so as to obtain a homogeneous resin of biodegradable material indicated with M; and a charging step, designated with 101-3, for adding bio-rice starch, i.e. biological rice starch, and inorganic fillers or charges of pulverized glass to the resin of biodegradable material M, to act as charges or fillers within the resin of PLA.

In particular, in this preparation step 101 of the resin M of biodegradable material, ATBC is advantageously used, as well as a plasticizer, also as a wetting agent to wet preliminary the PLA, in granular form, before using ethyl acetate to solubilize the PLA.

In fact, once wet with the ATBC, the granules of PLA form a block which is then easily and effectively solubilized with the ethyl acetate, so as to obtain a solution in which the PLA granules are uniformly and homogeneously dispersed.

The process 100 of the invention for producing and manufacturing wallpaper 10 further comprises, after the preparation step 101 of the biodegradable and spreadable material M: a spreading or coating step, indicated with 102, to spread the spreadable emulsion of biodegradable material M on the support sheet 11 so as to form on the latter the ecological and biocompatible decorative layer 12; an evaporation step, indicated with 103, to evaporate the ethyl acetate present in the decorative layer 12, of biodegradable material M, spread on the support sheet 11 , so as to make the decorative layer 12 acquire a consistency such as to make it embossable; and an embossing step, indicated with 104, for embossing, after the evaporation step 103, the decorative layer 12 formed on the support sheet 11 , so as to obtain the wallpaper 10 of the invention, ecological and biocompatible.

The process 100 also comprises a final roll-over step for rolling, i.e. winding on a roll, the wallpaper 10 which is produced.

Finally, the wallpaper 10, thus produced, is provided to be printed on the embossed surface of the respective decorative layer 12, so as to exhibit a given decoration, wherein this final decoration printing operation is usually performed by means of a digital printing apparatus separate from the plant implementing the process 100 for the production of the wallpaper 10.

The coated paper sheet constituting the support sheet 11 , on which the biodegradable material M is spread in the process 100, so as to form the decorative layer 12, has a grammage of between 80 and 100 g/m ² , preferably 85 g/m ² , and the spreading of the biodegradable material M on the same support sheet 11 is made so as to obtain a sheet of paper with the decorative layer 12 spread over it, having a thickness of between 300 and 700 microns, preferably 500 microns.

In particular, according to a preferred embodiment, the decorative layer 12 which is spread on the support sheet 11 has a thickness of 400 microns, so as to obtain an embossing effect, in the final product, i.e. the wallpaper 10, which is equal to that obtainable with a conventional coating material containing in its formulation PVC (PolyVinilChloride).

In this regard, it can be observed that this decorative layer with a thickness of 400 microns goes well beyond the limit of the maximum thickness of 150 microns of the bioplastic and biodegradable films, produced by extrusion by means of the current machines, offered by the prior art.

Furthermore, the inorganic fillers or charges of pulverized glass, used in the charging step 101-3 of the process 100 for preparing the homogeneous mixture of biodegradable material M, are preferably constituted by the product offered on the market by the company 3M with the trade name "Glass bubbles".

Optionally, in the process 100 of the invention, it is possible to add green mica in a minimum dosage in the biodegradable mixture M, in order to give it a green colouring.

For the sake of completeness of information, the chemical structure of the PLA, i.e. of one of the two basic biodegradable components included in the composition of the biodegradable material M, to be spread on the support sheet 11 , is shown below.

Furthermore, again for reasons of completeness of information, Fig. 5 shows a technical sheet of a PLA available and offered on the market by a generic supplier with the abbreviation EXT 404 (M), wherein this technical sheet illustrates the various characteristics of the lactic acid polymer or PLA (PolyLActide or PolyLActic acid) which is used, in granular form, to be solubilized in ethyl acetate so as to obtain the medium viscous resin which is then mixed with the biodegradable plasticizer ATBC, the bio rice starch, and the inorganic charges to prepare the resin of biodegradable material M to be spread on the support sheet 11 in order to produce the ecological and biocompatible wallpaper 10 of the invention.

Always for the sake of completeness and as synthesis of the above description, a preferred formulation, in weight percentages, having a purely indicative value, of the resin of biodegradable material M which is spread on the support sheet 11 to produce the ecological wallpaper 10, is indicated below:

ATBC 20,73 %

PLA (EXT 404 (M)) 40,41 %

Glass bubbles 3M 21 ,59 % organic rice starch 17,27 %

It is clear therefore that the weight percentages of the components of this biodegradable material resin M can vary depending on a variety of circumstances and factors and in particular on the applications in which the wallpaper 10 of the invention is intended to be used, as it is known to those skilled in the art.

The process 100 of the invention for producing the ecological and biocompatible wall paper 10 has also the considerable advantage of being realizable and implementable in a machine or plant, indicated with 200 in Figure 4, already used or usable for producing conventional, non-ecological wallpaper.

In particular, the plant 200 comprises: an inlet section, generally designated by the reference numeral 201 , adapted to receive and be fed continuously by the support sheet 11 ; a spreading station 202 configured to spread the mixture of biodegradable material M on the support sheet 11 so as to form on the latter, while advancing along the plant 200, the decorative layer 12; an evaporation station 203 configured to evaporate the ethyl acetate present in the decorative layer 12 spread on the support sheet 11 , so as to render this decorative layer 12 suitable to be embossed; an embossing station 204 configured to emboss the decorative layer 12, i.e. to impart a raised decorative pattern thereto, so as to complete the formation of the ecological and biocompatible wallpaper 10; and a roll-over station 205, arranged in an area at the outlet of the plant 200, configured to roll, i.e. to wind on a roll, the wall paper 10 which is produced.

As already specified, the wallpaper 10 of the invention, once produced by the plant 200, is provided to be digitally printed, by means of a specific printing apparatus, on the surface of the embossed decorative layer 12, so as to present on such decorative layer 12 the desired decoration.

The technologies and apparatus used for digital printing of the decoration on the decorative layer 12 of the wallpaper 10 are known and can be the most various ones and, for example, they can be based on inkjet printing technology or other technologies well known to those skilled in the art.

It follows that the wallpaper 10 of the invention can be offered on the market either in the form of a raw or semi-processed product, with the decorative layer 12, embossed, white and not yet printed, in which case such decorative layer 12 can be printed with the desired decoration by those who acquire this wallpaper 10 on the market, or optionally it can be offered in the form of a final product, having the desired decoration, ready to be applied to the wall or masonry to be coated.

Tests and certifications concerning the ecological and biocompatible wallpaper process and paper of the invention

Both the process 100 of the invention and the wallpaper 10 produced by this process 100 have been the subject of numerous and in-depth tests aimed in particular at experimentally verifying the characteristics and properties of this wallpaper 10, ecological and biocompatible.

For the sake of completeness, Fig. 2 shows, at sections (a)-(c), photographs of some samples, in the form of rolls, obtained and produced in the context of these tests, of the ecological and biocompatible wallpaper 10 1 of the invention.

It is noted that these photographs show the wallpaper 10, in roll form, with the decorative layer 12, embossed, not yet printed and therefore devoid of decoration.

Fig. 2 itself shows, at sections (d)-(e), photographs of a sample of wallpaper 10 on which a colored decoration indicated with 12' has been digitally printed on the surface of the respective decorative layer 12.

As it has been seen from the tests carried out, the resin of biodegradable material M, prepared with the process 100 of the invention, to be spread on the support sheet 11 has a working viscosity of about 7,400 cps (centipoise). Therefore, thanks to this working viscosity, it is possible to easily spread this resin of biodegradable material M on the support sheet 11 so as to form the decorative layer 12.

As a further information, it is also pointed out that the wallpaper 10 of the invention has been the subject of numerous tests concerning and aimed at its certification, in view of its offer in the market, wherein these tests have been totally positive, providing results and data perfectly in the norm.

In particular, the certification tests, carried out in a specialized laboratory on various samples and batches of rolls of wallpaper 10, have concerned, as foreseen by the UNI EN 12149:1999 standards on wallpaper, the determination of the migration of heavy metals and other substances, of the content of Chloride of Vinyl Monomer (CVM) and the release of formaldehyde in the bio mixture, i.e. in the resin of biodegradable PLA-based material which is used to make the wallpaper 10 of the invention, and have provided, as said, data fully in line with the above-mentioned standards.

Moreover, these certification tests, carried out in accordance with technical standard EN 16640:2017, have also shown in the bio mix or mixture a presence of biobased carbon, i.e. derived from biomass, equal to 74%, as a fraction of the total carbon, therefore still in the norm.

Still the bio mix or mixture used to produce the wallpaper 10 of the invention, subjected to gas chromatographic screening tests, has not shown the presence of compounds with a critical toxicological profile.

Therefore, in summary, the data obtained from the certification of the wallpaper 10 of the invention have fully confirmed, in addition to its innovative characteristics as regards the compliance with ecological and biocompatibility requirements, its full compliance with the current regulations.

Variants and further embodiments of the invention

Of course, without prejudice to the principle and basic concept of the present invention, it is also clear that its embodiments, either as a process or as a product, in the form of wallpaper, can be subject to variations, modifications and improvements with respect to what has been described and illustrated heretofore, without departing from the scope and scope of the invention itself.

For example, according to a first variant, the wallpaper 10 of the invention can comprise and be associated with one or more further layers, in addition to those constituted by the support sheet 11 and by the decorative layer 12, embossed, wherein these one or more further layers have in general the function of enhancing and/or giving specific characteristics to the wallpaper 10, as well as of adapting it according to the specific applications and uses for which it is intended.

Furthermore, the process for producing wallpaper of the invention can comprise further treatments than those described above and the relative steps, depending also in this case on the specific application and use to which wallpaper is intended.

Moreover, according to a further variant, in the process 100 for producing the ecological and biocompatible wallpaper 10 of the invention, the PEG 300 (PolyEthylene Glycol 300) can be used as an alternative to the ATBC (AcetilTriButilCitrate), as a plasticizer for plasticizing the PLA resin, although the PEG 300 has the drawback of a slightly acid odour.

Still, in the preparation step of the biodegradable material resin M, it is possible, as an alternative to the glass bubbles product of 3M, to use, in order to provide the inorganic fillers of powdered glass, the product known as Tiopac PT coated, which is a precipitated calcium carbonate exhibiting similar characteristics to those of this Glass bubbles product of 3M but having a lower cost.

It is also clear, as already pointed out, that the applications and uses of the invention, i.e. of the wallpaper, in the form of either a process or a product, can concern and be directed to various fields, and therefore respond to various needs and requests.

For example, the wallpaper 10 can be configured and adapted to exhibit nonflammability properties, so as to be used in those environments in which, for safety reasons, the absence of materials suitable for igniting is required.

For this purpose, the wallpaper 10 of the invention could include among its components ammonium polyphosphate, which is specifically a material suitable to impart the non-flammability characteristic to the compounds in which it is present.