JP2006249839A - Indoor interior-finishing panel, and floor panel and construction method for double floor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a panel for a double floor, which hardly changes an appearance, for example, prevents the coming-off of a decorative material from the panel and the discoloration of the decorative material even after long-term use, and which facilitates construction, and a method for inexpensively constructing the double floor by using the panel for the double floor. <P>SOLUTION: The floor panel for the double floor, which is made of a woody material-filled resin and the surface of which is decorated, is used for the double floor which is installed on a floor foundation bed in such a manner that a space is interposed. The floor panel is composed of a woody material-filled thermoplastic resin molding which is molded by pressurizing a thermoplastic resin mixture, obtained by mixing and melting a filler, particularly, a woody material, while cooling the thermoplastic resin mixture. A recess, which is provided in such a grid pattern that an upper end of a supporting leg of the floor panel can be mounted, is provided on the backside of a floor panel body. When the floor panel body is molded, a surface finishing material is arranged on the top surface of the thermoplastic resin mixture and integrated with it. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  INDUSTRIAL APPLICABILITY The present invention relates to an interior / interior panel and a double floor in which the surface of a resin molded product is decorated, which is molded by cooling and pressing a molten thermoplastic resin mixture mixed with a filler such as a wood-based material TECHNICAL FIELD The present invention relates to a floor panel for construction and a method of constructing a double floor using the floor panel.

  Pressurize while cooling a laminated material made of woody materials such as pulverized or cut wood, especially wood and bamboo, or a mixture of these woody materials and thermoplastic resin, while cooling. A panel made of a molded product of a wood-based material-filled resin is a synthetic resin and has a wood texture and moldability, and is also useful as a building panel because it effectively uses waste wood and recycled plastic.

  Conventionally, as a method for obtaining a panel made of a wood-based material, for example, a fixed-size material in which arrayed lignocellulose fibers are fixed with an adhesive, and the lignocellulose fibers are about 6 inches (about 15 cm) to about 4 cm. Feet (about 122 cm) long, about 0.05 inches (about 0.1 cm) to about 0.25 inches (about 0.6 cm) wide, and about 0.05 inches (about 0.1 cm) to about 0 .5 inches (about 1.3 cm) in thickness, and the strength of the obtained sizing material is not less than the strength of at least one grade of lumber cut and sampled from the above-mentioned lignocellulosic fiber wood species. There has been proposed the above-mentioned sizing material, which has a resin solid content of the adhesive and a density of the obtained sizing material (see, for example, Patent Document 1).

Moreover, it is a plate-like product, the plate-like product has a thickness of 25 mm or more, is cut out from a single-layer panel made of a wood wafer, the wafer is aligned in a certain length direction, When the wafer is measured in the longitudinal direction in the large plane of the single-layer panel, the average deviation with respect to the major axis of the panel is in the range of 0 to 10 degrees, orthogonal to the large plane and in the longitudinal direction of the panel The average deviation when the wafer is measured in the length direction within a small plane is within a range of 0 to 5 degrees, and the wafer has an average length of 200 mm or more when measured in the grain direction of the wafer. The shaped product forms a width portion of the plate-like product by a pair of cut surfaces separated by a predetermined distance, and the cut surface is substantially parallel to the long axis of the single-layer panel from which the plate-like product is cut out. Wafer board plate products are known That (for example, see Patent Document 2.).

  Panels used for architectural purposes are cut into the desired dimensions from the fixed-size materials described in Patent Document 1, the plate-shaped products described in Patent Document 2, and the wood-based material-filled resin described in Patent Document 3. Used.

The fixed-dimension material described in Patent Document 1 and the plate-shaped product described in Patent Document 2 are both arranged in the length direction of the cellulose fiber or the elongated wooden wafer along the length direction of the product, and a binder as required. Are mixed and stacked in a wood-based mat, and then obtained by pressing or heating. Since it has high strength, it can also be applied as a wood-based structural material.
Japanese Patent Publication No. 50-17512 Japanese Patent No. 2527761

  However, the panels made of the wood-based material in Patent Documents 1 and 2 are all made of a wood-based material. Therefore, when this is used, for example, the nails are pulled out even if nailing is possible. There are problems of material strength and durability that sometimes crack, the wood texture of the surface is excellent, but the appearance and feel is bad, and it was necessary to decorate with a finishing material from the viewpoint of surface properties as well .

  In particular, when used as an interior material such as an interior wall, cloth, paper, synthetic resin film or sheet, or a wallpaper made of a composite of these, or when used as a flooring, carpet, cork board, makeup, etc. Covering with a plate or the like is performed. Both of these are on-site construction, requiring a double work process of floor construction and surface finishing, which is labor intensive and costly, and the finish may vary greatly depending on the operator's wrinkles.

  In order to prevent such a situation, it is conceivable to give a desired surface decoration to the panel in advance to obtain a product. Examples of the decorating method include a method of adhering the decorating material to the panel with an adhesive, and a method of laminating the decorating material and pressing it when the panel is molded.

  However, in the method using an adhesive, after long-term use, the used adhesive may deteriorate and the decorating material may be peeled off from the panel, or the adhesive may be discolored to deteriorate the appearance. Further, in the method of laminating a decorative material at the time of panel formation, since the panel is formed by a heat press, a heat history is applied to the decorative material. Therefore, for example, if the decorating material has a lot of voids, such as cloth, the type of decorating material used may be limited, or it may be stretched or discolored during heating There is. Furthermore, when it becomes necessary to peel off after construction, there is a problem that the surface decorative material does not peel off.

  The present invention is an interior / interior panel whose appearance is difficult to change, such as the decorative material does not peel off and discolor even after long-term use, a double-floor panel whose appearance hardly changes even after long-term use, and which is easy to construct, This was done for the purpose of providing an inexpensive double floor construction method using this double floor panel.

  An interior / interior panel according to claim 1 is an interior / interior panel in which a surface of a resin molded product formed by pressing a molten thermoplastic resin mixture mixed with a filler is cooled. And when shape | molding this resin molded product, the decorating material is arrange | positioned on the upper surface of a thermoplastic resin mixture, and it pressurizes, cooling, and is shape | molded integrally, It is characterized by the above-mentioned.

  The floor panel for a double floor according to claim 2 (invention 2) is a floor panel for a double floor which is used for a double floor which is installed with a space on a floor base. The panel is made of a resin molded product that is molded by cooling and pressing the molten thermoplastic resin mixture mixed with a filler, and the upper end of the floor panel support legs can be attached to the back of the floor panel body. When the floor panel body is molded, a surface finishing material is disposed on the upper surface of the thermoplastic resin mixture, and pressed while cooling, and is integrally molded. And

  The construction method (invention 3) of the double floor according to claim 3 is a construction method of the double floor using the floor panel for the double floor of the invention 2, and the adjacent floor panels are only 0.5 mm to 3 mm. It is arranged to be separated and supported by support legs, and there is no double floor surface finish.

  The panel main body used in the inventions 1 to 3 is made of a wood-based material-filled resin made of a molded product formed by pressurizing while cooling a filler, particularly a thermoplastic resin mixture mixed with a wood-based material. is there. Woody materials include wood, bamboo pulverized or cut bodies, seeds or their shells or threshing residues, plant fibers, etc., using plant-derived materials consisting of any one or a mixture of two or more of them. it can. It is desirable to reduce the consumption of forest resources by using waste wood such as waste wood, thinned wood, etc., generated during the demolition of buildings as pulverized or cut wood and bamboo.

  As the thermoplastic resin, a known thermoplastic resin or curable resin can be used depending on the application, and is not particularly limited. For example, as an example, PP (polypropylene), PE (polyethylene), polystyrene, polybutene, polyisoprene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, acrylonitrile-styrene series such as AAS, ABS, ACS, AES Examples thereof include single resins or composites such as copolymers, polyamide resins, polycarbonates, ester resins such as polyethylene terephthalate, polybutylene terephthalate, methacryl, polyurethane, polyvinyl chloride, and chlorinated polyvinyl chloride.

  Furthermore, an additive such as an adhesive component can be used in combination to increase the interfacial adhesive strength between the resin and the plant piece. In non-polar resins such as polyolefin, modified resins such as acid-modified polyolefin or acid-modified olefin oligomer Is preferably added. Further, it is preferable to use plastic waste material for recycling.

  When a woody material is pulverized or crushed, it usually has an elongated shape along its fiber direction. Therefore, if a tensile stress is applied in the fiber direction of the plant piece, an excellent tensile strength can be exerted on the panel. Therefore, it is desirable that the fiber directions are substantially aligned.

  In the inventions 1 to 3, the woody material is preferably in the range of 30% by weight to 80% by weight in the total raw materials. The mixing ratio of the wood-based material and the thermoplastic resin is preferably such that the weight ratio of (wood-based material: other material) is in the range of (30:70) to (80:20), more preferably (40: 60) to (70:30), more preferably (50:50) to (60:40).

  If the proportion of the wood-based material is more than 80% by weight, mutual dispersion becomes difficult during melt mixing, and the thermoplastic resin does not physically bond with the wood-based material, so that the nest can easily enter the molded product and the moldability deteriorates. There are things to do. If the ratio of the wood material is less than 30% by weight, the thermoplastic resin is completely filled in the holes of the temporary conduit of the wood material, and the porous characteristic of the wood material may be lost. There is a problem that the appearance and feel of the molded product is deteriorated, and it is difficult to obtain a sufficient wood texture. Therefore, it is preferable to appropriately adjust the supply amount so that the mixing ratio is within the above range.

  Other additives are not particularly limited, and known additives may be appropriately selected and used according to the application. For example, additives such as α, β-unsaturated carboxylic acid monomers, admixture promoters such as acid-modified olefins and acid-modified low-molecular olefins; reinforcing materials such as glass fibers and carbon fibers; UV absorbers and UV degradation prevention Various stabilizers such as additives and antioxidants; (internal) lubricants such as lead stearate, colorants such as pigments and extender pigments; various fillers, preservatives, flame retardants, antioxidants, nucleating agents, etc. Various additives etc. are mentioned. These additives can be used alone or in combination of two or more.

  The addition of a mixing accelerator is preferable because the adhesion between the woody material and the thermoplastic resin is improved. As the mixing accelerator, those that form a hydrophilic group in the end of the polymer or in the molecule are preferable, and the type and bonding position of the hydrophilic group are not particularly limited. Modified olefin-based admixture accelerators that form hydrophilic groups in the polymer and admixture accelerators having hydrophobicity and hydrophilicity are particularly preferred because they exhibit excellent effects even at low amounts.

  The addition amount of the various additives is not particularly limited as long as the addition amount is appropriately adjusted according to the kind of the additive so that a desired effect can be obtained. For example, when MAPP (maleic anhydride modified polypropylene) is used as an additive, the additive is preferably added in an amount of 2 parts by mass or more with respect to a total of 100 parts by mass of the thermoplastic resin (PP) and the woody material. More preferably, it is suitably added so as to be 3 parts by mass or more, preferably 5 parts by mass or less, more preferably 4 parts by mass or less. If the additive amount is small, the additive may not sufficiently exert the effect of improving the adhesion between the thermoplastic resin and the wood-based material. Even if it is added in a large amount, a remarkable improvement effect may not be obtained.

  The wood-based material-filled resin panels according to the inventions 1 to 3 are obtained by mixing a thermoplastic resin, a crushed wood-based material, and other additives as necessary, and melting the thermoplastic resin to obtain a wood-based material mixed resin. It can be molded by pressurizing while cooling the melt. For example, the wooden material and thermoplastic resin are put into a mixing container provided with a plurality of stirring blades at a predetermined weight, and the stirring blade is rotated at a high speed to stir the wood pieces and the thermoplastic resin. It can be manufactured by a method in which a molten mixture obtained by mixing a thermoplastic resin melted by frictional heat and a wood-based material is cooled while being pressed and press-molded.

  The wood-based material is supplied to a known melt mixing apparatus together with a thermoplastic resin and other additives as required. Each of these materials may be provided with a feeder and supplied separately to the apparatus, or a premixed material may be supplied to the apparatus, and the supply method is not particularly limited.

  The melt mixer is not particularly limited as long as it is an apparatus that forms a molten mixture obtained by melting a thermoplastic resin and mixing a wood-based material. For example, a method using a general extrusion device, or a rotating shaft inserted into a melt mixing chamber is provided with a plurality of stirring blades for melting thermoplastic resin by frictional heat, which are mixed in the preceding process. A melt mixer (for example, a K-mixing machine, a cohan) is obtained by feeding a wood-based material and a resin into the chamber and rotating a stirring blade to obtain a molten mixture in which the wood-based material is mixed with a molten thermoplastic resin. A method using a product (trade name)). In this method using the melt mixer, the wood material and the thermoplastic resin can be melt-mixed without any pretreatment such as preliminary drying, and without making the wood material into fine powder. .

  The wood-based material-filled resin thus made into a molten mixture is filled in a press mold in a molten state, and a molded product using the wood-based material-filled resin is obtained by pressurizing while cooling.

  When interior panels are molded with a wood-based material-filled resin, a decorative material is placed on the top surface of the molten mixture of the wood-material-filled resin in the molding die, and the whole decorative material is cooled and pressurized. And is integrally molded.

  The decorating material is on the surface of the indoor interior panel and has a function of mainly improving the appearance of the panel. As the decorating material, a material having a void and a surface state in which a molten thermoplastic resin enters or entangles in the void and exhibits an anchor effect is preferable, but it is not particularly limited. Fibers, synthetic fibers or fabrics, nonwoven fabrics, and papers that use these together; synthetic resin films and sheets that have been processed to increase surface tension such as void processing, embossing, or plasma processing, etc., can be selected as appropriate As long as it is used.

  When these decorating materials are arranged on the upper surface of the molten mixture and are pressurized while being cooled together with the decorating material, the decorating material and the wooden material-filled resin are integrally formed and do not peel off after many years. Moreover, since the decorating material itself is not heated, the effect that it is hard to discolor can also be expected.

  In the floor panel for double floors of the invention 2, the recessed part provided in the grid | lattice form which can mount | wear with the upper end part of the support leg of a floor panel is provided in the back surface side of a floor panel main body. This concave portion is a place where the upper end portion of the support leg that is arranged on the floor base and supports the floor panel is mounted when a double floor is constructed with a space on the floor base. Since the placement location of the support legs can be set arbitrarily, the floor panel can be placed at any location on the floor base by attaching the upper end of the support leg to the recess provided at any location on the floor panel. Can do.

  In addition, when the floor panel is molded with a wooden material-filled resin, a decorative material is disposed on the upper surface of the molten mixture of the wooden material-filled resin in the molding die, and the whole decorative material is cooled. Pressurized and integrally molded.

  The decorative material is on the surface of the floor panel and mainly has a function of improving the appearance of the panel. As the decorating material, a material having a void and a surface in which a molten thermoplastic resin enters or gets entangled in the void to exert an anchor effect is preferable, but it is not particularly limited. Fibers, synthetic fibers or fabrics, nonwoven fabrics, carpets, etc. used in combination with them; synthetic resin films and sheets processed to increase surface tension such as void processing, embossing or plasma processing, decorative paper, decorative wood, etc .; cork and general A typical piece of decorative wood, such as a thin piece or a thin plate, may be used, and it may be appropriately selected and used as necessary.

  When these decorating materials are arranged on the upper surface of the molten mixture and are pressurized while being cooled together with the decorating material, the decorating material and the wooden material-filled resin are integrally formed and do not peel off after many years. Moreover, since the decorating material itself is not heated, there is almost no discoloration.

  Invention 3 is a construction method of a double floor using the floor panel for double floors of Invention 2. The double floor is constructed by supporting the floor panel of the invention 2 on a floor base with a support. This support tool can change the height of the floor panel from the floor base. The method of changing the height is not particularly limited. For example, as an example, a support bolt that can change the height of the floor panel, a base that is arranged on the floor base and supports the support bolt, and the support bolt Examples include a fitting base provided at the upper end portion and provided with a through hole through which a support bolt is inserted and supporting the floor panel. The upper part of the fitting base of the support is fitted into an arbitrary recess among a plurality of recesses formed by a plurality of grid ribs provided on the back surface of the floor panel body.

  The construction method of the double floor of the invention 3 arrange | positions the said several support tool on a floor base, adjusts the height from the floor base of a support tool upper end part to a predetermined distance, and each adjusted height. The upper part of the support part is attached to the concave part on the back surface of the floor panel. At this time, it arrange | positions so that the opposing sides of adjacent floor panels may leave | separate only 0.5 mm-3 mm. This gap is necessary because the size of the wood-based material-filled resin changes due to temperature changes. If it is less than 0.5 mm, floor panels may rub against each other and floor noise may occur. There is a possibility that the gap is conspicuous and lacks in design.

  Furthermore, in the invention 3, since the surface finishing material (decorative material) is integrally formed on the floor panel surface in advance, the decorative material is not peeled off at the time of construction, and there is almost no discoloration. Color unevenness does not occur throughout the surface. Therefore, it is not necessary to refinish the double floor.

  The interior / interior panel according to the first aspect of the present invention is formed by integrating the decorating material when the wood-based material-filled resin is melted and molded while being cooled and pressed in the mold. The material will not peel off the panel. In addition, since pressure is applied while molding and cooling, there is no heat history applied to the decorating material, so there is almost no discoloration and the appearance is unlikely to change.

  Since the floor panel for double floors of the invention 2 is formed by providing a recess for mounting the support on the back surface of the floor panel body made of a wood-based material-filled resin, only the support is mounted in the recess. So double floor construction is easy. Furthermore, when the wood-based material-filled resin is melted and molded while being cooled and pressed in the mold, the decorative material is molded as a unit, so that the decorative material can be peeled off from the floor panel even after long-term use. There is no. In addition, since pressure is applied while molding and cooling, there is no heat history applied to the decorating material, so there is almost no discoloration and the appearance is unlikely to change.

  The construction method of the double floor of the invention 3 uses the floor panel of the invention 2, so that the floor surface finishing material (decorative material) is not peeled off at the time of construction and there is almost no discoloration, so the floor surface after construction Color unevenness does not occur throughout. Therefore, it is not necessary to perform the surface finishing work of the double floor again, and the construction cost is reduced. .

  Next, the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of an example of an interior interior panel according to the first aspect of the present invention. FIG. 2 is a sectional view of an example of a floor panel for a double floor according to the second aspect. FIG. 3 is a cross-sectional view showing an example of a state in the vicinity of opposite sides of adjacent floor panels at the time of double floor construction according to the invention 3, and a support is mounted in a recess of the floor panel. FIG. 4 is a cross-sectional view showing an example of a wood-based material-filled resin melt mixer. FIG. 5 is a cross-sectional view of an example of a state in which a decorative material is placed on a molten wood-based material-filled resin placed in a molding die and press-molded.

  In FIG. 1, an interior interior panel 1 is formed by integrating a decorating material 12 on one side of a panel body 11 and integrally forming the panel body.

  In FIG. 2, the floor panel 2 for a double floor is provided with a recess 33 on the back surface of the panel body 21 where the upper end portion of the support 3 can be mounted, and a decorative material 32 is laminated on the front surface side so as to be integrated with the floor panel body. It is molded.

  The interior interior panel 1 or the floor panel 2 is manufactured by pressurizing a melt of a resin based on a wood-based material while cooling it with a molding die. The wood-based material-filled resin may be melt-mixed by a general extruder or the like, but for example, a melt-mixer as shown in FIG. 5 may be used. The melt mixer in FIG. 4 is a cross-sectional view showing a part of an example of a melt mixer for a wood-based material-filled resin G. A hopper 41 of the melt mixer 4 is charged with a thermoplastic material, a wood material whose shape, size, moisture content, etc. are adjusted, and a raw material G mixed with other additives as required in a predetermined blending amount. A predetermined amount of the mixed raw material G is sent to the chamber 42 by a screw 43 that is rotated by an electric motor (not shown) or the like. A plurality of stirring blades 421 are provided in the chamber 42 for mixing the raw material G and melting the thermoplastic resin by frictional heat generated at that time.

  A gap S is provided between the stirring blade 421 and the inner wall of the chamber 42 in order to smoothly rotate the stirring blade 421. When the wood-based material is mixed with the molten thermoplastic resin, the wood crushing chips of a predetermined size in the wood-based material maintain the original shape after the melt-mixing. When the wood material is mixed into the molten resin by the stirring blade 421, a large number of wood crushing chips having a large size are present on the surface side of the mass of the molten mixture, and wood materials having a smaller size are Distributed inside. The fine powdery wood raw materials dispersed on the inside are dispersed inside the mass of the molten mixture as a filler, resulting in a mass of the molten mixture having a small central part size and a large surface side size, and an unevenly distributed size. . The molten mixture thus obtained is taken out from the outlet 44.

  The taken-out molten mixture is put in a molding die 5 in a molten state, and is pressurized while being cooled by a press machine to form the interior interior panel 1 and the double floor floor panel 2. As an example, FIG. 5 shows a case where the interior interior panel 1 is molded. In the case of the floor panel 2 for double floors, only the shape of the mold is different and the molding method is the same, so it will not be described.

  The molten mixture of the wood-based material-filled resin G is placed in the molding die 5 in a molten state, and the decorating material 12 or 22 is placed on the surface thereof, and is molded by pressurizing while cooling it. Therefore, since the thermoplastic resin melted at the time of pressurization bites into the voids or rough surface of the decorative material 12 or 22, the decorative material 12 or 22 is molded in a state of being laminated integrally on the surface of the molded product. The Moreover, since it is not heated at the time of pressurization, the decorating material 12 or 22 is not heated except for heat when it first comes into contact with the molten mixed resin, and therefore there is no thermal history, so the interior interior panel 1 or The floor panel 2 is obtained.

  FIG. 3 is an example of the vicinity of the opposite side of the adjacent floor panel 2 when constructing a double floor using the floor panel 2 of the invention 3, and the support 3 is mounted in the recess 23 of the floor panel 2. Shows the state. The support 3 is disposed on the floor base B. In the case of this illustrated example, the support 3 includes a support bolt 31 that can change the height of the floor panel 2, a base 32 that is disposed on the floor base B and supports the support bolt 31, and the support described above. Examples thereof include a fitting base 33 provided at the upper end of the bolt 31 and provided with a through hole 34 through which the support bolt 31 is inserted and supporting the floor panel 2. The upper portion of the fitting base 33 of the support 3 is fitted into an arbitrary recess 23 among the plurality of recesses 23 provided on the back surface of the floor panel 2 main body.

  As an example of use of the present invention, it is a floor of a house, a store, or an office centering on an apartment. In particular, in construction with a limited construction period, finishing is completed by laying the groundwork.

It is sectional drawing of an example of the panel for indoor interior of invention 1. FIG. It is sectional drawing of an example of the floor panel for double floors of invention 2. FIG. It is sectional drawing which shows an example of the state of the opposing edge vicinity of the adjacent floor panel at the time of the double floor construction of the invention 3, and the support tool was mounted | worn by the recessed part of the floor panel. It is sectional drawing which shows an example of the melt mixer of wood type material filling resin. It is sectional drawing of an example of the state which distributes a decorating material to the molten wood type material filling resin put in the shaping die, and is press-molded.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Panel for interior interior 11 Panel main body 12 Decorating material 2 Floor panel for double floors 21 Panel main body 22 Decorating material 23 Recess 3 Supporting tool 31 Support bolt 32 Base 33 Fitting base 34 Through hole 4 Melt mixer 41 Hopper 42 Chamber 421 Stirrer blade 43 Screw 44 Discharge port 5 Press molding die 51, 52 Press panel B Floor base G Wood material filling resin S Gap

Claims (3)

  An interior / interior panel that decorates the surface of a resin molded product that is molded by cooling and pressing a molten thermoplastic resin mixture mixed with a filler, and when molding the resin molded product, An interior / interior panel, wherein a decorating material is disposed on an upper surface of a thermoplastic resin mixture and is pressed and integrally molded while being cooled.   A surface-decorated double-floor floor panel used for a double-floor installed with a space on the floor base, wherein the floor panel is melted by mixing a filler. It is made of a resin molded product that is molded by cooling while cooling, and the floor panel body is provided with a concave portion provided in a lattice shape on which the upper end of the support leg of the floor panel can be mounted, and the floor panel body is molded In this case, a floor panel for a double floor is characterized in that a surface finish is disposed on the upper surface of the thermoplastic resin mixture, and is pressed and molded integrally with cooling. A method for constructing a double floor using the floor panel for a double floor according to claim 2, wherein the adjacent floor panels are arranged so as to be separated from each other by 0.5 mm to 3 mm and supported by support legs, and A double floor construction method characterized by the absence of a heavy floor surface finish.

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