KR100730542B1 - The soundproofing board using the floor of building and method thereof - Google Patents

Abstract

The present invention relates to a triple-structure building floor sound insulation panel which blocks noise generated between a floor and a floor of an apartment and a house formed of a concrete steel structure, absorbs various impact sounds and vibrations, Wherein the low-hardness embossing layer comprises a low-hardness embossing layer having a functional pattern at the bottom, a low-density independent bubble layer having a low hardness at the top of the low-density embossing layer, And a high hardness, independent bubble layer having a high degree of hardness, and the respective layers are integrally molded and formed into a triple structure.

The manufacturing method includes a metering step of weighing EVA resin, PE resin, filler, thermal conductive agent, colorant (hereinafter referred to as " raw material "), foaming assistant and crosslinking agent with a metering device so as to adjust a blending ratio, A kneading step of mixing and kneading using a kneader, a kneading step of kneading the kneaded raw material with a foaming assistant and a cross-linking agent, and a step of molding the kneaded mass of the material into a sheet state into which the kneaded material can be put into a press A cooling step of cooling and fixing the foamed building floor soundproofing plate; and a cooling step of cooling and solidifying the soundproofing plate for the building floor, And a cutting step of cutting the sound insulation board for a building floor.

The above-mentioned triple-structure soundproofing board for a floor of a building is formed of a triple structure of a low-hardness embossing layer, a low-density independent bubble layer and a high-hardness independent bubble layer, and is formed into a foamed state Therefore, it is possible to block the noise generated between the floor and the floor of the apartment and the apartment, to smoothly absorb various impact sounds and vibrations, to reduce impact noise and vibration, There is also an effect of heat insulation performance that can prevent leakage of cold air to the inside or outside.

In addition, when a soundproofing plate for a building floor of a triple structure is installed between a concrete slab layer and a lightweight foamed concrete layer, which are the bottom layer of a building, a low-caliber and highly- It has an excellent durability after construction.

Buildings, houses, sound insulation boards, floors

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a soundproofing board for a floor of a building,             

1A is a perspective view of a conventional soundproof plate for a building floor of a single hardness

Fig. 1B is a perspective view of a conventional single-hardness sound insulation board for building floor,

FIG. 2 is a schematic view of a conventional soundproof panel for a building according to the present invention,

Fig. 3 is a perspective view of a soundproof panel for a building floor according to the present invention having a triple structure

Fig. 4 is a schematic diagram showing a construction of a triple-structure building floor soundproofing plate according to the present invention,

5 is a process diagram showing a manufacturing process of a triple-structure soundproofing board for a building floor according to the present invention

Fig. 6 is a process diagram showing the manufacturing process of a triple-structure soundproofing board for a building according to the present invention,

Description of the Related Art [0002]

10. Floor finish 20. Cement mortar

30. Hot water circulation pipe 40. Lightweight foam concrete layer

50. Soundproofing board for flooring of triple structure 51. Low-hardness embossing layer

52. Low-density independent bubble layer 53. High-hardness independent bubble layer

60. Concrete slab layer 70. Air layer

80. Adhesive

S1. Low-hardness forming sheet step S2. High hardness forming sheet stage

200. Weighing stage 300. Dough stage

400. kneading step 500. forming (sheet) step

600. Aging stage 700. Press stage

800. Cooling stage 900. Foundation stage

The present invention can block noises generated between the floor and the floor of an apartment and a house, smoothly absorb various impact sounds and vibrations to reduce impact noise and vibration, In particular, a low-hardness embossing layer having a functional pattern at the bottom and a low-hardness embossing layer at the bottom of the low-hardness embossing layer, and a method of manufacturing the same. And a low-hardness independent bubble layer having a low hardness and a high-hardness independent bubble layer having a high hardness at the top of the low-degree-of-freedom bubble layer are integrally molded. The present invention relates to a sound insulation board for a building floor.

Recently, as the building has become high-rise, the frame of the apartment structure, the apartment house or the high-rise building is almost H-beam or I-beam. The thickness of the concrete slab layer, which is the bottom layer of the building, is being made thinner.

As described above, the floor impact sound generated between the floor and the floor is becoming a serious problem due to the thinning of the concrete slab layer which is the bottom layer of the building by using the H beam or I beam as the frame of the building.

In addition, when the residents of the apartment complex are not satisfied with the residential environment, dissatisfaction with the noise between the floor and the floor occupies a large proportion.

Generally, a floor structure between a floor and a floor of a building is formed by forming a lightweight foamed concrete layer for improving insulation on a concrete slab layer as a bottom layer of a building, installing a hot water circulation pipe on the lightweight foamed concrete layer, It is common to apply a mortar with a mortar, and to apply the mortar to the floor surface with a floor finish.

However, in recent years, a soundproof panel for a building floor, which can block noise generated between the floor and the floor and can absorb various impact sounds and vibrations, is installed between the concrete slab layer as the bottom layer of the building and the lightweight foamed concrete layer have.

The above-mentioned soundproofing boards for building floors mainly use foamed plastic foamed by adding styrofoam called foam polystyrene and synthetic resin called plasticity material or plastic by adding a crosslinking agent and a foaming agent .

However, as shown in FIG. 1A, the conventional sound insulation board 100 for a building floor has a single hardness and an upper and a lower surface formed in a flat shape, so that noise generated in a wide range of frequency bands, lightweight impact sound, There was a problem.

The hardness is generally divided into low-hardness and high-hardness, and the low-hardness sound insulation board for a floor of a building has a large effect of blocking the noise of a light impact sound and a high frequency portion. On the other hand, a lightweight foamed concrete used for forming a lightweight foamed concrete layer The water is absorbed well on the floor panel for the floor having low hardness and the lightweight foamed concrete layer is hardened, so that there is a problem that cracks or spaces are not generated.

The above-mentioned soundproof panel for building floor of high hardness has a great effect to block heavy impact sound and low-frequency noise, and the moisture contained in lightweight foamed concrete used for forming a lightweight foamed concrete layer is used for building floor of high hardness Even if the lightweight foamed concrete layer is hardened because it is not absorbed well by the soundproofing plate, there is an effect that cracks or spaces are not generated.

However, since the conventional sound insulation board 100 for a building floor is constructed between a concrete slab layer as a bottom layer of a building and a lightweight foamed concrete layer using a single hardness sound insulation board 100 as described above The noise of low frequency and high frequency band can not be smoothly blocked and the light impact sound and heavy impact sound can not be smoothly reduced.

As shown in FIG. 1B, between the concrete slab layer, which is the bottom layer of the building, and the light-weight foamed concrete layer, a low-hardness building floor sound insulation board 101 and a high- ) Were stacked on each other with an adhesive.

 However, the sound insulation board 103 for building floor including the conventional low-hardness building floor soundproofing board 101 and the high-hardness building floor soundproofing board 102 is not suitable for noise, vibration and impact noise generated between the floor and the floor But after a lapse of time, there is a gap between the low-hardness sound insulation board 101 and the high-hardness floor soundproofing board 102 in the long term, Noise and vibration and impact noise generated in the vehicle are reduced.

In addition, since the surface of the building floor sound insulation board 101 of low hardness, which is in close contact with the floor surface of the concrete slab layer 60, which is the bottom layer of the building, is formed in a horizontal plane so that noise, vibration, There is a problem that it is transmitted directly to the lower layer.

As shown in FIG. 2, the construction method first constructs a low-hardness sound insulation board 101 on the concrete slab layer 60, which is the bottom layer of the building, and then applies the adhesive 80 on the low- A lightweight foamed concrete layer 40 for improving insulation is formed on the soundproof panel 102 for a building floor having a high degree of hardness and a hot waterproof concrete layer 40 is formed on the lightweight foamed concrete layer 40, The circulation pipe 30 is installed and then covered with sand and then treated with a cement mortar 20 and the floor finish 10 is applied to the floor surface of the plastered floor. There is a problem that the soundproofing plate 101 for building floor and the soundproofing plate 102 for building floor are separated from each other due to a decrease in the adhesive strength and the durability is lowered.

The object of the present invention is to solve the above-mentioned problems, and it is an object of the present invention to smoothly block the noise generated between a floor and a floor of an apartment and a house formed of a concrete steel structure, And has a waterproof and heat insulating performance.

Another object of the present invention is to provide a low-hardness embossing layer having a functional pattern at the bottom, a low-density independent bubble layer having a low hardness at the top of the low-density embossing layer, And a high-degree-of-freedom independent bubble layer having a plurality of high-strength bubble layers.

Another object of the present invention is to provide a soundproofing board for a floor of a building having a triple structure by weighing an EVA resin, a PE resin, a filler, a heat conduction agent, a colorant (hereinafter referred to as "raw material"), A kneading step of mixing and kneading the metered raw materials with a kneader, a kneading step of kneading the kneaded raw material with a foaming auxiliary agent and a cross-linking agent, and kneading the kneaded mass of the material A molding step of molding the sheet material into a state capable of being put into a press; an aging step of aging the material of the sheet formed in the forming step; a pressing step of foaming the aged material; And a cutting step of cutting the cooling-molded building sound-insulating board for building And a method for manufacturing a floor sound insulation board.

According to another aspect of the present invention, there is provided a sound insulation board for a floor of a building, comprising: a low-hardness embossing layer having a functional pattern on the bottom; A low-hardness, independent bubble layer having a low hardness on top of the low-hardness embossing layer; A high-hardness, independent bubble layer having a high hardness on the low-density independent bubble layer; And the production method thereof includes a metering step of metering the EVA resin, the PE resin, the filler, the heat conduction agent, the colorant (hereinafter referred to as "raw material"), the foaming assistant, ; Mixing and kneading the metered raw materials using a kneader; A kneading step of adding a foaming auxiliary and a cross-linking agent to the kneaded raw material and kneading the kneaded raw material; A molding step of molding the kneaded mass of the material into a sheet state into which the kneaded material can be fed; An aging step of aging the material on the sheet formed in the forming step; A pressing step of foaming the aged material; A cooling step of cooling and fixing the foam-molded building floor sound insulation plate; A cutting step of cutting the cooling-molded building floor sound insulation panel; The soundproof panel for a building floor has a triple structure and is formed in a foamed state capable of absorbing shocks. Therefore, noise generated in a floor of an apartment house and a floor of the apartment house So that it is possible to smoothly absorb various impact sounds and vibrations to reduce impact noise and vibration, and also to prevent indoor high-temperature air from flowing out to the lower part or to prevent cold air from entering into the interior There is also an effect of insulation performance that can be done.

In addition, when a soundproofing plate for a building floor of a triple structure is installed between a concrete slab layer and a lightweight foamed concrete layer, which are the bottom layer of a building, a low-caliber and highly- There is also an excellent durability after construction.

The soundproof panel for a building floor is characterized in that a low-hardness embossing layer, a low-hardness independent bubble layer, and a high-hardness independent bubble layer are integrally formed and formed into a triple structure.

In addition, the triple-structure building floor soundproofing board is divided into a low-hardness and high-hardness, and an embossed layer having a low diameter is formed under the low-hardness independent bubble layer. The embossed layer also corresponds to a low-hardness, independent bubble layer.

The embossing layer can be a shape that can smoothly block noise generated between a floor and a floor of an apartment and a house, smoothly absorb various impact sounds and vibrations, and reduce impact noise and vibration.

In addition, one or more of coral, yellow loam, germanium, white rock, volcanic ash, and green oyster flour, which are beneficial to the human body, may be suitably used in the above-mentioned triple-structure soundproofing board for building floors.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a soundproof board for a building floor according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 is a perspective view of a soundproof panel for a building floor according to an embodiment of the present invention. FIG. 4 is a perspective view of a triple structure of the present invention. FIG. 5 is a process diagram showing a manufacturing process of a triple-structure soundproofing board for a floor according to the present invention, FIG. 6 is a view illustrating a process of manufacturing a triple- And the process steps of separating the manufacturing process of the soundproofing plate for the lower and higher hardness are respectively shown in FIG.

3, the triple-structure building floor sound insulation board 50 according to the present invention includes a low-hardness embossing layer 51 having a functional pattern at the bottom and a low-hardness embossing layer 51 at the top of the low- A low-hardness, independent bubble layer 52 having a low hardness; and a high-hardness, independent bubble layer 53 having a high hardness above the low-hardness, independent bubble layer 52; .

The sound insulation board 50 of the triple-structure building floor according to the present invention is characterized in that the low-hardness embossing layer 51, the low-hardness independent bubble layer 52 and the high-hardness independent bubble layer 53 are integrally formed, Triple structure.

The high hardness, free-standing bubble layer 53 comprises 65 to 75 wt% of ethylene vinyl acetate (EVA), 20 to 27 wt% of polyethylene (PE), 1.9 to 8 wt% of filler, 1 to 4 wt% 1 to 3% by weight of a foaming auxiliary, 0.1 to 0.5% by weight of a crosslinking agent; Kneaded and kneaded to produce a foaming agent, and its hardness is preferably 35 to 40. [

A colorant may be added to the high-hardness, independent bubble layer 53 to improve the appearance of the triple-walled soundproofing board 50. The colorant may be added to the high- Is 0.5 to 1.5.

Here, the term raw material refers to an EVA resin, a PE resin, a filler, a heat conductive agent, a colorant, a foaming auxiliary agent, and a crosslinking agent.

The low-density, open-celled foam layer 52 comprises 70 to 85 wt% of ethylene vinyl acetate (EVA), 11 to 25 wt% of polyethylene (PE), 1.5 to 3 wt% of a filler, 1.4 to 4 wt% 1 to 3% by weight of a foaming auxiliary, 0.1 to 0.5% by weight of a crosslinking agent; Kneaded and kneaded to produce a foam, and the hardness is preferably 30 to 35. [

A colorant may be added to the low-density independent bubble layer 52 for the appearance of the triple-structure building floor soundproofing board 50. The colorant may be added to the low- Is 0.5 to 1.5.

Here, the term raw material refers to an EVA resin, a PE resin, a filler, a heat conductive agent, a colorant, a foaming auxiliary agent, and a crosslinking agent.

The low-hardness embossing layer 51 is formed on the lower portion of the low-hardness, write-enabled bubble layer 52. The low-hardness embossing layer 51 shields the noise generated between the layer and the layer of the apartment and the multi- , And it can be a shape that absorbs various impact sounds and vibrations smoothly and can reduce an impact sound and vibration.

The fillers used for the low-hardness embossing layer 51, the low-hardness independent bubble layer 52 and the high-hardness independent bubble layer 53 are calcium carbonate, white carbon, magnesium carbonate, zinc oxide, diatomaceous earth, talc, alumina white , Mica powder, aluminum sulfate, barium sulfate, calcium sulfate, and light bees, and is characterized in that white carbon and magnesium carbonate are mixedly used do.

The thermal conductive agent used for the low-hardness embossing layer 51, the low-density independent bubble layer 52 and the high-hardness independent bubble layer 53 is clay, and the foaming aid is sodium bicarbonate, ammonium carbonate, And JTR-M + aid, dpt, and ac of an industrial ADCA system, and one or more of JTR-M + aid, dpt, Is used.

Further, the crosslinking agent is characterized by using DCP which is an organic peroxide.

As shown in Fig. 5, a method for manufacturing a triple-layered soundproofing board for a floor of a building comprises measuring EVA resin, PE resin, filler, thermal conductive agent, colorant (hereinafter referred to as " raw material "), A kneading step (200) of mixing the metered raw materials with a kneader, a kneading step (300) of mixing the kneaded raw material with a foaming auxiliary and a crosslinking agent, and kneading A forming step (500) of forming a kneaded mass of the kneaded material into a sheet state into which the kneaded material can be put into a press, an aging step (600) of aging a material on the sheet formed in the forming step A cooling step (800) for cooling and fixing the foamed sound insulation board (50) for a building floor having a triple structure, and a cooling step (700) for cooling and shaping the triple structure For building floors Including eumpan 50 cutting step 900 for cutting the characterized in that is made.

6, the metering step 200, the kneading step 300, the kneading step 400, the molding step 500, and the aging step 600 are performed by a low- Hardness forming sheet step S2 and the hardness forming sheet step S2 from the pressing step 700 to the cutting step 900 are performed separately from the sheet stage S1 and the hardness forming sheet stage S2, The low-hardness forming sheet and the high-hardness forming sheet formed in this step are superimposed to be integrally formed.

The low-hardness forming sheet and the high hardness forming sheet mean a sheet for forming the low-hardness embossing layer 51, the low-density independent bubble layer 52 and the high-hardness independent bubble layer 53 in the pressing step 700 .

In the kneading step 300, the raw materials are kneaded in a kneader preheated at 100 to 110 ° C at 25 to 35 rpm for 10 to 20 minutes, preferably at 105 ° C and 30 rpm for 15 minutes.

In the kneading step 400, the raw materials are kneaded in an oven bar preheated at 80 to 90 DEG C at 25 to 35 rpm for 5 to 15 minutes, preferably at 85 DEG C and 30 rpm for 8 minutes.

When the kneading step 400 is completed, the sheet is formed into a sheet having a thickness of 1 to 2 mm by using a rolling mill, and the sheet formed in the forming step 500 is formed into a size Horizontally and vertically.

The kneading step 300 and the forming step 500 are separated and formed into a low hardness forming sheet step S1 and a high hardness forming sheet step S2 as described above, The low-hardness sheet and the high-hardness sheet are subjected to aging (600) for aging for 24 hours to stabilize the sheet.

The low-hardness sheet and the high-hardness sheet which have undergone the aging step 600 are superposed on each other and crosslinked and foamed by pressurization at 145 to 155 kgf / cm 2 for 10 to 30 minutes in a press mold preheated to 145 to 155 ° C, Deg.] C for 15 to 22 minutes under a pressure of 150 kgf / cm < 2 >

A cooling step 800 for sufficiently cooling and fixing the foamed sound insulation board 50 of the foamed triple structure for a building floor is performed.

The thickness of the foamed sound insulation board 50 of the foamed triple structure may be 10 to 100 mm, but is preferably 15 to 30 mm.

The cooled and aged triple-structure building floor soundproofing board 50 is cut horizontally and vertically according to the use standard, and is cut through a cutting step 900 with reference to the center.

The triple-structure building floor sound insulation plate 50 of the present invention, which is manufactured by the above-described manufacturing method, effectively blocks the floor impact sound and noise of the low-frequency area band of 1000 Hz or less in the high- And a low-hardness embossing layer 51 is provided at the lower part of the low-density independent bubble layer 52. The low-hardness bubble layer 52 absorbs and absorbs floor impact noise and noise of the used frequency band of 1000 Hz or more in the low- When the sound insulation board 50 having the triple structure is placed on the concrete slab layer 60 as a building floor layer, an air layer 70 is formed between the concrete slab layer 60 and the low-hardness embossing layer 51 And the air layer 70 absorbs vibration generated by the impact between the layer and the layer and has the effect of canceling residual noise or impact noise.

Further, as shown in FIG. 4, the triple-structure soundproofing board 50 of the present invention has the effect of simplifying the construction method as compared with the conventional construction method, and reducing labor costs.

The construction methods are as follows: First, a soundproofing board 50 for a building floor is constructed on a concrete slab layer 60, which is a bottom layer of a building, a lightweight foamed concrete layer 40 is formed on the soundproofing board 50, The hot water circulation pipe 30 may be installed on the layer 40 and then covered with the sand and then treated with the cement mortar 20 and then the floor finish 10 may be applied on the surface of the surface treated.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art.

Therefore, the true scope of protection of the present invention should be determined only by the claims.

As described above, according to the triple-structure building floor soundproof panel according to the present invention, in the noise, vibration, and impact sound generated between the floor and the floor of the apartment and the apartment house, the low- Effectively shields floor impact noise and noise, effectively absorbs and cancels floor impact noise and noise in the medium frequency range of over 1000Hz in low-density independent bubble layer. And a low-hardness embossing layer provided under the low-hardness independent bubble layer. When the triple-structure soundproofing plate for a building floor is placed on a concrete slab layer as a building floor layer, the concrete slab layer and the low- And the air layer absorbs the vibration generated by the impact between the layer and the layer and has the effect of canceling residual noise or impact noise. In addition, when a soundproofing plate for a building floor of a triple structure is installed between a concrete slab layer and a lightweight foamed concrete layer, which are the bottom layer of a building, a low-caliber and highly- There is also an excellent durability after construction.

Claims (12)

A low-density embossing layer having a functional pattern on the bottom; A low-hardness, independent bubble layer having a low hardness on top of the low-density embossing layer; A high-hardness, independent bubble layer having a high hardness on the top of the independent bubble layer; Wherein the embossed layer, the low-degree-of-freedom independent bubble layer and the high-degree-of-freedom independent bubble layer are integrally formed. The method according to claim 1, The high hardness, From 65 to 75% by weight of ethylene vinyl acetate (EVA); 20 to 27% by weight of polyethylene (PE); 1.9 to 8% by weight of a filler; 1 to 4% by weight of heat conduction; 1 to 3% by weight of a foaming auxiliary; 0.1 to 0.5% by weight of a crosslinking agent; Is kneaded, kneaded and kneaded to produce a foam, and the hardness thereof is preferably 35 to 40. The sound insulation board for a floor of a building having a triple structure. The method according to claim 1, The low hardness, From 70 to 85% by weight of ethylene vinyl acetate (EVA); From 11 to 25% by weight of polyethylene (PE); 1.5 to 3% by weight filler; 1.4 to 4% by weight of a heat conduction agent; 1 to 3% by weight of a foaming auxiliary; 0.1 to 0.5% by weight of a crosslinking agent; Is kneaded, kneaded and kneaded to produce a foam, and the hardness thereof is preferably 30 to 35. A sound insulation board for a floor of a building having a triple structure. 3. The method according to claim 1 or 2, The filler, And one or more selected from the group consisting of calcium carbonate, white carbon, magnesium carbonate, zinc oxide, diatomaceous earth, talc, alumina white, mica powder, aluminum sulfate, barium sulfate, calcium sulfate, A soundproof plate for a floor of a triple structure. 3. The method according to claim 1 or 2, Characterized in that the heat conduction agent uses a clay; The foaming aid may be selected from one or more selected from sodium bicarbonate, ammonium carbonate, nitrogen compounds, JTR-M + aid, dpt, ac of industrial ADCA, Wherein the crosslinking agent is a DCP which is an organic peroxide. 3. The method according to claim 1 or 2, Characterized in that the coloring agent is further added with a coloring agent, wherein the coloring agent has 1 to 3 raw material blend ratios of the high-hardness and low-hardness independent bubble layers of 100. 3. The method according to claim 1 or 2, Characterized in that a mixture of one or more of coral, yellow loam, germanium, white rock, volcanic ash, and green ash powder beneficial to man is used. A metering step of metering a EVA resin, a PE resin, a filler, a heat conduction agent, a colorant (hereinafter referred to as " raw material "), a foaming assistant,  Mixing and kneading the metered raw materials using a kneader; A kneading step of adding a foaming auxiliary and a cross-linking agent to the kneaded raw material and kneading the kneaded raw material; A molding step of molding the kneaded mass of the material into a sheet state into which the kneaded material can be fed; An aging step of aging the material on the sheet formed in the forming step; A pressing step of foaming the aged material; A cooling step of cooling and fixing the foam-molded building floor sound insulation plate; A cutting step of cutting the cooling-molded building floor sound insulation panel; Wherein the sound absorbing plate is made of a synthetic resin. 10. The method of claim 8, The refreshing step; A kneading step; A kneading step; A molding step; Wherein the aging step is performed by separating the low-hardness sheet and the high-hardness sheet, and the low-hardness sheet and the high-hardness sheet are integrally formed from the pressing step to the cutting step. (METHOD FOR MANUFACTURING SOUND BODY FOR BOTTOMS) 10. The method according to claim 8 or 9, In the kneading step, the raw material is kneaded in a reader (Kneader) preheated to 100 to 110 ° C at 25 to 35 rpm for 10 to 20 minutes, preferably 105 ° C at 30 rpm for 15 minutes. (METHOD FOR MANUFACTURING SOUND BODY FOR BOTTOMS) 10. The method according to claim 8 or 9, In the kneading step, the raw material is heated to 80 to 90 DEG C in an oven basin At 25 to 35 rpm for 5 to 15 minutes. ≪ RTI ID = 0.0 > 15. < / RTI > 10. The method according to claim 8 or 9, Wherein the low-hardness sheet and the high-hardness sheet are subjected to crosslinking foaming by pressurizing the pre-heated press mold at 145 to 155 kgf / cm 2 for 10 to 30 minutes in the pressing step. (EN) METHOD FOR MANUFACTURING.

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