JP2018053642A - Ceiling material for water section - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ceiling material for a water section with a reduced water absorption amount.SOLUTION: A ceiling material for a water section 1 of the present invention includes a substrate 10 having a foamed resin layer 14 and a first metal layer 16 provided on one surface of the foamed resin layer 14, and the substrate 10 has an open cell ratio of 5 to 25%. The substrate 10 preferably has a second metal layer 18 provided on the other surface of the foamed resin layer 14. The ceiling material for water section 1 preferably further includes a decorative layer 12 provided on the surface of the first metal layer 16. It is preferable that the decorative layer 12 is formed of a nonwoven fabric.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a ceiling material for water.

As a material for the ceiling material, gypsum, rock wool, calcium silicate / fiber composite, and the like are used from the viewpoint of excellent fire resistance and heat insulation.
When ceiling materials made of these materials are used in places where the humidity is high such as around the water where condensation is likely to occur, a large amount of moisture is sucked in and the weight of the ceiling material increases. In particular, a ceiling material made of gypsum has a large amount of water absorption, is weak against moisture, and has a remarkable decrease in strength due to water absorption.
As a result, there is a problem in that the appearance of the ceiling material becomes worse when the deflection of the ceiling material increases and can be discriminated visually.

  Therefore, Patent Document 1 discloses a ceiling panel that has been processed so that the bending of the ceiling material generated by absorbing moisture is not visually noticeable, and the manufacturing cost is reduced without increasing the thickness of the ceiling panel. Has been.

JP 2014-173227 A

However, although these ceiling boards are processed so that the deflection generated by moisture absorption is not visually noticeable, the amount of water absorption itself cannot be suppressed.
Then, this invention aims at the ceiling material for water circumferences which suppressed water absorption.

In order to solve the above problems, the present invention provides the following means.
That is, the ceiling material for plumbing of the present invention includes a substrate having a foamed resin layer and a first metal layer provided on one surface of the foamed resin layer, and the substrate has an open cell ratio of 5 ~ 25%.
The substrate preferably has a second metal layer provided on the other surface of the foamed resin layer.
It is preferable that the water ceiling material further includes a decorative layer provided on the surface of the first metal layer.
It is preferable that the decorative layer is formed of a nonwoven fabric.

  In addition, in this invention, the water circumference means places using water, such as a kitchen, a washroom, a bathroom, and a pool.

  According to the water-borne ceiling material of the present invention, the amount of water absorption can be suppressed.

It is sectional drawing of the ceiling material for watering concerning one Embodiment of this invention.

The water-borne ceiling material of the present invention includes a substrate having a foamed resin layer and a first metal layer provided on one surface of the foamed resin layer.
In FIG. 1, the ceiling material 1 for water circumferences concerning one Embodiment of this invention is shown.
The water-ceiling ceiling material 1 of the present embodiment is a composite plate for ceiling including a substrate 10 and a decorative layer 12. The substrate 10 and the decorative layer 12 are laminated via a third adhesive layer 24.
In the present embodiment, when the ceiling material 1 for water is installed on the ceiling, the decorative layer 12 side is the lower side (front side).

(Thickness and basis weight of water-ceiling ceiling material)
The thickness of the ceiling material 1 for water is preferably 1.8 to 4.9 mm, more preferably 1.9 to 4.5 mm, and further preferably 2.5 to 4.5 mm. If the thickness of the ceiling material 1 for water is not less than the lower limit, the strength can be sufficiently maintained. If the thickness of the ceiling material 1 for watering is below the said upper limit, processing, such as a cutting | disconnection, will become easy at a construction site, and the water absorption of the ceiling material 1 for watering can be restrained low.

The basis weight of the plumbing for the ceiling material 1 is preferably 500 to 1000 g / ^{m 2,} more preferably 600~1000g / ^{m 2,} more preferably 600~800g / ^{m 2.} If the basis weight of the ceiling material 1 for water is greater than or equal to the lower limit, the strength can be sufficiently maintained. If the basis weight of the water-ceiling ceiling material 1 is not more than the above upper limit value, the water absorption amount of the water-ceiling ceiling material 1 can be suppressed to a lower level.

[substrate]
The substrate 10 includes a flat foamed resin layer 14, a first metal layer 16 provided on one surface of the foamed resin layer 14, and a second metal layer provided on the other surface of the foamed resin layer 14. 18. The foamed resin layer 14 and the first metal layer 16 are laminated via the first adhesive layer 20. The foamed resin layer 14 and the second metal layer 18 are laminated via the second adhesive layer 22.
In addition, the board | substrate 10 should just have the 1st metal layer 16 provided in the one surface of the foamed resin layer 14 and the foamed resin layer 14, and has the 2nd metal layer 18. May not be included.

(Thickness of substrate, basis weight)
The thickness of the substrate 10 is preferably 1.0 to 4.0 mm, more preferably 1.5 to 3.5 mm, and still more preferably 1.5 to 3.0 mm. If the thickness of the board | substrate 10 is more than the said lower limit, the intensity | strength of the ceiling material 1 for water circumferences can fully be maintained. If the thickness of the board | substrate 10 is below the said upper limit, the water absorption amount of the ceiling material 1 for water supply can be restrained low.

The basis weight of the substrate 10 is preferably ^{500~1000g / m 2, 550~800g / m} 2 is more preferable. If the basic weight of the board | substrate 10 is more than the said lower limit, the intensity | strength of the ceiling material 1 for water circumferences can fully be maintained. If the basic weight of the board | substrate 10 is below the said upper limit, the water absorption amount of the ceiling material 1 for watering can be restrained low.

(Open cell ratio)
The open cell ratio of the substrate 10 is measured by the following method. First, a plurality of sheet-like samples of 25 mm long × 25 mm wide were cut out from the substrate 10. The cut samples were overlapped so that there was no space, and the thickness was 50 mm to obtain a test piece. The outer dimension of the obtained test piece was measured to 1/100 mm using “Digimatic Caliper” manufactured by Mitutoyo Corporation, and the apparent volume (cm ³ ) was determined.
Next, using an air comparison type specific gravity meter 1000 Model (manufactured by Tokyo Science Co., Ltd.), it was determined volume of specimen (cm ³⁾ by 1-1 / 2-1 atm method ASTM D2856-87.
The open cell ratio (%) was calculated by the following formula. The average value of the open cell ratio of the five test pieces was determined.
Open cell ratio (%) = 100 × (apparent volume−air comparison type hydrometer measurement volume) / apparent volume In the above measurement, the test piece was subjected to JIS K7100: 1999 symbol 23/50, in a second grade environment for 16 hours. After storage, the measurement was performed in a JIS K7100: 1999 symbol 23/50, second grade environment. The air comparison type hydrometer was corrected with a standard ball (large 28.96 cc, small 8.58 cc).
The open cell ratio of the substrate 10 can be adjusted by the type and amount of the bubble adjusting agent, the amount of the foaming agent, the resin temperature at the time of extrusion foaming, and the like during the production of the foam sheet described later.

In the present invention, the open cell ratio of the substrate 10 is 5 to 25%, preferably 6 to 20%, more preferably 7 to 15%.
When the open cell ratio of the substrate 10 is 5% or more, the dimensional change at the time of the bonding process is stabilized, so that the bonding processability is improved. Can be kept low.

(Foamed resin layer)
As a material of the foamed resin layer 14, what can be normally used as a foamed resin layer in a well-known composite board can be used without a restriction | limiting. In the present invention, from the viewpoint of foamability and durability, the material of the foamed resin layer 14 is a general polystyrene resin, polypropylene resin, polyethylene resin, modified polyphenylene ether resin, polyester resin, or the like. it can.

The polystyrene resin used for the foamed resin layer 14 constituting the substrate 10 is not particularly limited, and examples thereof include a homopolymer or copolymer of a styrene monomer. In addition, as a polystyrene resin, a copolymer having a styrene monomer as a main component, obtained by copolymerizing a styrene monomer and a vinyl monomer copolymerizable with the styrene monomer. May be used.
As the polystyrene-based resin, a polystyrene-based resin having 50% by mass or more of structural units based on styrene with respect to all the structural units is preferable, and polystyrene is more preferable.

Examples of the styrene monomer include styrene, α-methyl styrene, vinyl toluene, chlorostyrene, ethyl styrene, i-propyl styrene, dimethyl styrene, bromostyrene, and the like.
A styrene-type monomer may be used individually by 1 type, and may use 2 or more types together.

Examples of vinyl monomers copolymerizable with styrene monomers include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and cetyl (meth) acrylate. Bifunctional monomers such as (meth) acrylonitrile, dimethyl maleate, dimethyl fumarate, diethyl fumarate, ethyl fumarate, divinyl benzene, alkylene glycol dimethacrylate, and the like.
A vinyl-type monomer may be used individually by 1 type, and may use 2 or more types together.

The polystyrene resin used as a raw material can be a commercially available polystyrene resin, a polystyrene resin produced by a method such as suspension polymerization, a polystyrene resin that is not a recycled material (virgin polystyrene), a used foamed plate, Recycled raw materials obtained by reclaiming polystyrene-based resin foam molded articles (such as food packaging trays) can be used. As the recycled material, it is possible to use a recycled material obtained by recovering a used foamed plate or polystyrene-based resin foam-molded product and regenerating it by a limonene dissolution method or a heating volume reduction method.
Polystyrene resins may be used alone or in combination of two or more.

  The foamed resin layer 14 contains additives such as an antioxidant, a heat stabilizer, an ultraviolet absorber, a lubricant, a mold release agent, a dye, a pigment, an antistatic agent, and a filler as long as the physical properties are not impaired. May be.

(Thickness of foamed resin layer, basis weight)
The thickness of the foamed resin layer 14 is preferably 0.8 to 3.8 mm, more preferably 1.3 to 3.3 mm, and still more preferably 1.3 to 2.8 mm. If the thickness of the foamed resin layer 14 is equal to or greater than the lower limit value, the strength of the ceiling material 1 for watering can be sufficiently maintained. If the thickness of the board | substrate 10 is below the said upper limit, the water absorption amount of the ceiling material 1 for water supply can be restrained low.

The basis weight of the foamed resin layer 14 is preferably from 60~200g / ^{m 2,} more preferably 70~180g / ^{m 2,} more preferably 80 to 150 g / ^{m 2.} When the basis weight of the foamed resin layer 14 is equal to or greater than the lower limit, the strength of the water-ceiling ceiling material 1 can be sufficiently maintained. If the thickness of the board | substrate 10 is below the said upper limit, the water absorption amount of the ceiling material 1 for water supply can be restrained low.

In the foamed resin layer 14, in addition to the resin component, it is preferable that a foam regulator is further contained. By containing the cell regulator, it is easy to obtain a foam sheet having a low open cell ratio and good moldability.
Examples of the air conditioner include inorganic fillers such as talc, mica, mica, and montmorillonite.
A bubble regulator may be used individually by 1 type, and may be used in combination of 2 or more type.

(Metal layer)
A first metal layer 16 is provided on one surface of the foamed resin layer 14, and a second metal layer 18 is provided on the other surface. Thereby, the intensity | strength of the board | substrate 10 can fully be maintained and water absorption can be restrained low by the water repellency of the surface of the board | substrate 10. FIG.
As the 1st metal layer 16 and the 2nd metal layer 18, the well-known metal normally used for a composite board can be used, For example, an aluminum sheet, an aluminum alloy sheet, a stainless steel sheet, an iron sheet, a steel sheet And a metal sheet such as a titanium sheet. Especially, an aluminum sheet is preferable from a lightweight viewpoint.
The first metal layer 16 and the second metal layer 18 may be a single layer or multiple layers. Moreover, the 1st metal layer 16 and the 2nd metal layer 18 may be formed with the same metal, and may be formed with a different metal.

The thickness of the first metal layer 16 is 50 μm or more, preferably 50 to 180 μm, and more preferably 50 to 150 μm. If the thickness of the 1st metal layer 16 is more than the said lower limit, it is excellent in water repellency and can suppress the water absorption amount low. If the thickness of the 1st metal layer 16 is below the said upper limit, the process of cutting etc. will be easy at a construction site, and it will be easy to obtain the board | substrate 10 which was lightweight and excellent in workability | operativity.
The thickness of the second metal layer 18 is the same as the thickness of the first metal layer 16. The thickness of the first metal layer 16 and the thickness of the second metal layer 18 may be the same or different.

(Adhesive layer)
As the adhesive constituting the first adhesive layer 20 and the second adhesive layer 22, a known adhesive usually used for composite plates can be used, and a hot melt adhesive is preferable.
Any hot melt adhesive may be used as long as it can adhere the foamed resin layer 14 and the first metal layer 16 or the foamed resin layer 14 and the second metal layer 18. Agents, polyester hot melt adhesives, and the like. Examples of the polyolefin hot melt adhesive include trade name “X-2300” (manufactured by Kurabo Industries Co., Ltd.). Examples of the polyester-based hot melt adhesive include trade name “PES-111EE” (manufactured by Toagosei Co., Ltd.).
A hot-melt-adhesive may be used individually by 1 type, and may use 2 or more types together.

10-50 micrometers is preferable and, as for the thickness of the 1st adhesive bond layer 20, 20-40 micrometers is more preferable. If the thickness of the first adhesive layer 20 is within the above range, it was used for a long time even when the fixing interval of screws or the like was 30 cm or less in order to prevent bending due to its own weight when attaching the ceiling material 1 for watering. It is easy to suppress the occurrence of warping due to temperature difference between the front and back and the bending due to its own weight. Moreover, if the thickness of the 1st adhesive bond layer 20 is more than the said lower limit, it will be easy to adhere | attach the foamed resin layer 14 and the 1st metal layer 16 fully. If the thickness of the 1st adhesive bond layer 20 is below the said upper limit, since the amount of heat | fever applied at the time of bonding can be restrained low, a dimensional change can be made small and a bonding process can be stabilized.
The thickness of the second adhesive layer 22 is the same as the thickness of the first adhesive layer 20. The thickness of the 1st adhesive bond layer 20 and the 2nd adhesive bond layer 22 may be the same, and may differ.

[Coating layer]
As a decorative material for forming the decorative layer 12, a known decorative material used for a composite board can be used, and examples thereof include non-woven fabric (polyolefin-based non-woven fabric), non-combustible paper, resin film (olefin-based resin film, etc.), and the like. It is done.
The decorative layer 12 may be a single layer or a multilayer.

The basis weight of the decorative layer 12 is preferably ^{70~180g / m 2, 80~150g / m} 2 is more preferable. When the basis weight of the decorative layer 12 is equal to or more than the lower limit value, it is difficult to see the base (first metal layer), and a uniform design color tone is obtained. If the basic weight of the decorative layer 12 is less than or equal to the above upper limit value, the water absorption amount of the ceiling material 1 for watering can be kept low.

The decorative layer 12 is provided on the first metal layer 16 side of the substrate 10 via the third adhesive layer 24.
As an adhesive agent which forms the 3rd adhesive bond layer 24, the same thing as what was mentioned by the 1st adhesive bond layer 20 and the 2nd adhesive bond layer 22 is mentioned, for example.
10-50 micrometers is preferable and, as for the thickness of the 3rd adhesive bond layer 24, 15-40 micrometers is more preferable.

[Usage]
The water-ceiling ceiling material 1 can be used as a water-ceiling ceiling material. Among them, the ceiling material 1 for the water-use ceiling material 1 has a sufficient strength that is difficult to bend due to its own weight, and the amount of water absorption can be kept low. As particularly effective.
Specifically, the ceiling material attached to the ceiling of the place using water, such as a kitchen, a washroom, a bathroom, and a pool, is mentioned.

[Production method]
The manufacturing method of the ceiling material 1 for water circumferences is not specifically limited, For example, the method which has the following process (I) and (II) is mentioned.
Step (I):
A first metal sheet is overlaid on one side of the foam sheet via a hot melt adhesive. A second metal sheet is overlaid on the other surface of the foam sheet via a hot melt adhesive. The laminated body is subjected to thermocompression bonding and then cooled, and the first metal layer 16 is laminated on one surface of the foamed resin layer 14 via the first adhesive layer 20, and the other surface of the foamed resin layer 14. Then, the substrate 10 on which the second metal layer 18 is laminated through the second adhesive layer 22 is obtained.
Step (II):
The decorative layer 12 is stacked on the surface of the substrate 10 on the first metal layer 16 side via a hot melt adhesive, and after being subjected to thermocompression bonding, cooling is performed, and then the third adhesive is applied to the first metal layer 16 side of the substrate 10. The water-use ceiling material 1 in which the decorative layer 12 is laminated through the layer 24 is obtained.

(Method for producing foam sheet)
The method for producing a foam sheet of the present invention is a method in which a raw material composition containing a resin component containing a polystyrene resin and a foaming agent are melt-kneaded, extruded and foamed.
As a suitable production method of such a foam sheet, a known production method can be adopted, and examples thereof include the following production method (A) and production method (B). Among these, as a manufacturing method of such a foam sheet, the manufacturing method (A) is more preferable in terms of extrusion foamability and thermoformability.

Manufacturing method (A):
A circular die attached to the tip of the extruder after supplying a raw material composition containing a polystyrene-based resin and other resins and a raw material composition containing other components and a physical foaming agent to the extruder and melt-kneading them. After extrusion foaming from above, a cylindrical foam is obtained, and then the cylindrical foam is expanded and supplied to a mandrel for cooling, and then the cylindrical foam is placed between its inner and outer peripheral surfaces. A method for producing a foam sheet by continuously cutting and developing in the extrusion direction.

Manufacturing method (B):
By melt-kneading the raw material composition and the chemical foaming agent in an extruder and then extruding from a T-die attached to the tip of the extruder to produce a foamable sheet, and heating and foaming the foamable sheet A method for producing a foam sheet.

(Process (I))
Step (I) is a step of obtaining the substrate 10. Hereinafter, the step (I) will be described more specifically.
The foamed sheet and the metal sheet may be used by continuously unwinding from a state of being wound in a roll shape, or may be used by cutting into a desired shape in advance.
In the lamination of the foam sheet and the metal sheet, a hot melt adhesive may be applied to the surface of the foam sheet, or a hot melt adhesive may be applied to the surface of the metal sheet.

Examples of the method for applying the hot melt adhesive to the laminated surface of the metal sheet in the foamed sheet include the following methods (a) to (d).
(A) A method of laminating a foam sheet and a hot melt adhesive by coextrusion.
(B) A method of extruding and laminating a hot melt adhesive on the laminated surface of the metal sheet in the foam sheet.
(C) A method of laminating a film made of a hot melt adhesive on a foam sheet immediately after extrusion foaming.
(D) A method of laminating a film made of a hot-melt adhesive on the laminated surface of the metal sheet in the foamed sheet and thermocompression bonding.

Examples of the method for applying the hot melt adhesive to the surface of the metal sheet include the following methods (e) and (f).
(E) A method of removing the solvent by evaporating the solvent after applying the hot melt adhesive dissolved in the solvent to the metal sheet.
(F) A method in which a film made of a hot melt adhesive is thermocompression bonded to one side of a metal sheet.

The method for thermocompression bonding the foam sheet and the metal sheet is not particularly limited, and examples thereof include a method using a pair of rolls or a pair of pressure plates heated to a predetermined temperature.
100-180 degreeC is preferable and the heating temperature at the time of lamination | stacking of a foam sheet and a metal sheet has more preferable 110-170 degreeC. When the heating temperature is equal to or higher than the lower limit value, the foamed sheet and the metal sheet can be sufficiently bonded. If the heating temperature is equal to or lower than the upper limit value, the foam sheet is unlikely to shrink.

In step (I), the foamed sheet is preferably subjected to secondary foaming by heating during the lamination of the foamed sheet and the metal sheet.
The secondary foaming ratio at the heating temperature at the time of laminating the metal sheet in the foamed sheet is preferably 1.01 to 2.5 times, and more preferably 1.01 to 2.3 times. If the secondary foaming ratio of the foamed sheet is equal to or more than the lower limit, the foamed sheet is not easily crushed when the metal sheets are laminated, and the water-use ceiling material 1 having a sufficient thickness is easily obtained. If the secondary foaming ratio of the foamed sheet is less than or equal to the above upper limit value, the metal sheet is less likely to wrinkle when the metal sheet is laminated.
In addition, the heating temperature at the time of metal sheet lamination means the temperature which arithmetically averaged the minimum temperature and the maximum temperature among the surface temperatures of the foam sheet heated at the time of metal sheet lamination.

In the present invention, a foamed sheet obtained by secondary foaming is referred to as a foamed resin layer 14.
Also, a metal sheet laminated on one surface of the foam sheet is referred to as a first metal layer 16, and a metal sheet laminated on the other surface is referred to as a second metal layer 18.

The secondary foaming ratio of the foamed sheet can be measured by the following method.
A flat square test piece having a side of 10 cm is cut out from the foam sheet. The apparent volume V1 of the test piece is measured. Next, the test piece is supplied to a thermostatic bath maintained at the same temperature as the heating temperature of the foam sheet at the time of laminating metal sheets, and left for an arbitrary time. Next, the apparent volume V2 of the test piece is measured, and the secondary expansion ratio is calculated based on the following equation.
Secondary foaming ratio (times) = V2 / V1

The secondary foaming ratio of the foamed sheet at the heating temperature at the time of metal sheet lamination is the amount of foaming agent used in the production of the foamed sheet, the temperature of the resin (α) during extrusion foaming from the mold, and the use of the cell nucleating agent It can be controlled by adjusting the amount.
Specifically, the secondary foaming ratio of the foamed sheet tends to increase by increasing the amount of the foaming agent used and lowering the temperature of the resin (α) at the time of extrusion foaming from the mold. When the temperature of the resin (α) during extrusion foaming from the mold is increased, the secondary foaming ratio of the foamed sheet tends to decrease. When the use amount of the cell nucleating agent is increased, the secondary foaming ratio of the foamed sheet tends to be lowered.

(Process (II))
Step (II) is a step of overlaying the decorative layer 12 on the substrate 10.
Lamination | stacking of the board | substrate 10 and the decorative layer 12 can be performed similarly to process (I).
Also in the lamination of the substrate 10 and the decorative layer 12, a hot melt adhesive may be applied to the surface of the substrate 10, or a hot melt adhesive may be applied to the surface of the decorative layer 12. For example, a hot melt adhesive can be applied to the surface of the substrate 10 or the surface of the decorative layer 12 by the same method as the methods (e) and (f).

  The water-ceiling ceiling material of the present invention is not limited to the water-ceiling ceiling material 1 described above. For example, the water ceiling material of the present invention may not have a decorative layer.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by the following description.

[Evaluation of water absorption]
The amount of water absorption was measured based on the total water absorption test of JIS A 6901.
A test piece obtained by cutting the ceiling material into a size of 300 mm × 300 mm is prepared, and the test piece is dried to a constant weight in a dryer adjusted to 40 ± 2 ° C. The weight of the test piece when dried is measured with an accuracy of 1 g.
Next, the test piece is placed horizontally at a position of about 3 cm below the surface of water in 20 ± 3 ° C. water and allowed to stand for 2 hours. After 2 hours, the test piece is taken out, the water adhering to the surface is wiped off, and the mass at the time of water absorption is measured with an accuracy of 1 g.
The value obtained by converting the value of weight change before and after water absorption into the weight per 1 m ² was taken as the amount of water absorption.
In the present invention, water absorption is preferably 500 g / ^{m 2} or less, more preferably 470 g / ^{m 2} or less, 450 g / ^{m 2} or less is more preferred. A water absorption of 500 g / m ² or less is preferable because it is difficult to bend after construction as a ceiling material and it is difficult to apply a load to the building.

[Evaluation of bending strength retention before and after water absorption]
The evaluation of the bending strength retention before and after water absorption of the ceiling material was performed as follows.
Evaluation of water absorption amount A sample was cut from a test piece before water absorption and a test piece after water absorption into a long rectangular shape with a width of 50 mm and a length of 150 mm, according to JIS K7171-2009. The bending maximum point stress was measured.
Using a Tensilon universal testing machine (trade name “RTG-1310” manufactured by A & D Co., Ltd.), the maximum value of the bending strength of the peripheral frame material for containers was measured by a three-point push bending test. The measurement conditions were as follows.
・ Distance between jigs: 100 mm
Compression jig: an indenter having a tip dimension (R) of 5 mm, and a support base having a width of 67 mm and a corner dimension (R) of 2.5 mm having a 5 ° inclination starting from the portion in contact with the test piece.
・ Compression speed: 50 mm / min
-Push-bending distance: 30mm
The data of the data processing system MSAT0002RTF / RTG for the general purpose tester manufactured by A & D Co., Ltd. The thickness, width, and length of the test piece are entered into the 3-point push bending test, and automatically calculated data The bending maximum point stress was determined.
The bending strength retention was calculated from the calculated bending maximum point stress using the following formula.
Bending strength retention ratio (%) = Maximum bending point stress after water absorption / Maximum bending point stress before water absorption × 100

[Example 1]
A tandem type extruder having a second stage extruder connected to the tip of the first stage extruder was prepared. Mixture of polyphenylene ether and polystyrene resin (manufactured by Savic, trade name “NORYL EFN4230”, polyphenylene ether content: 70 mass%, polystyrene resin content: 30 mass%) 31.5 mass% and polystyrene (manufactured by DIC, (Product name “XC-515”) 100 parts by mass of modified polyphenylene ether resin consisting of 68.5% by mass and 0.13 parts by mass of talc masterbatch (base resin: PS talc amount: 40%) Was supplied to an extruder and melt-kneaded. Next, 5.23 parts by mass of liquefied butane as a foaming agent was injected into the first stage extruder and melt-kneaded with the modified polyphenylene ether resin. Next, continuously supplying the modified polyphenylene ether resin in a molten state to the second stage extruder connected to the tip of the first stage extruder, and adjusting the resin temperature to be 170 ° C., A cylindrical foam was obtained by extrusion foaming from a circular die attached to the tip of the second stage extruder.
Next, after gradually expanding the diameter of the cylindrical foam and supplying it to the mandrel, it is continuously cut and expanded in the extrusion direction at any location and wound into a roll as a long foam sheet. I took it. The discharge rate during extrusion foaming was 400 kg / hour, and the take-up speed was 32.3 m / min. The thickness of the obtained foam sheet was 1.5 mm, and the basis weight was 100 g / m ² .
Foam sheet unwinding (foamed resin layer) wound up in a roll shape, aluminum sheet (manufactured by Toyo Aluminum Co., Ltd., symbol A1N30-H18, first metal layer, second metal layer), olefin-based hot melt adhesive (Kurabo) The product name “Clambetter X-2300”, first adhesive layer, second adhesive layer) in this order, and laminated on both sides of the foam sheet at the same time, heated to 130 ° C. It supplied continuously between a pair of thermocompression-bonding belts, and thermocompression-bonded so that the surface temperature was 110 ° C. throughout. Subsequently, it cooled until the surface temperature became 34 degreeC, and obtained the elongate board | substrate (The ceiling material for water circumferences, Prototype 1) with a thickness of 1.96 mm. The substrate take-up speed was 3 m / min.
As shown in Table 1, the substrate of the obtained prototype 1 has an open cell ratio of 10.3%, basis weight of 580 g / m ² , water absorption of 7 g / m ² , bending strength before water absorption of 8.97 MPa, bending after water absorption. The strength was 8.97 MPa and the bending strength retention was 100.0%.

[Example 2]
Change the used aluminum sheet to the symbol A1N30-0 (first metal layer, second metal layer), and polyester-based non-woven fabric (made by Kureha Tech Co., Ltd., makeup layer) with a basis weight of 90 g / m ² An aluminum sheet (first metal layer) superimposed on one side of the substrate with an adhesive was continuously supplied between the thermocompression belts. A ceiling material for water circulation (prototype 2) was obtained in the same manner as in Example 1 except that the heating temperature of the thermocompression bonding belt was 140 ° C. and the surface temperature was 120 ° C.
As shown in Table 1, the resulting open cell rate of the substrate of prototype 2 12.5%, basis weight 700 g / ^{m 2,} the water absorption amount 325 g / ^{m 2,} before water absorption flexural strength 2.51MPa, bending after water absorption The strength was 2.49 MPa, and the bending strength retention was 99.2%.

[Example 3]
A ceiling material for water circulation (prototype 3) was obtained in the same manner as in Example 2 except that the heating temperature of the thermocompression bonding belt was 150 ° C and the surface temperature was 130 ° C.
As shown in Table 1, the resulting open cell rate of the substrate of prototype 3 21.0% grammage 700 g / ^{m 2,} the water absorption amount 403 g / ^{m 2,} before water absorption flexural strength 3.31MPa, bending after water absorption The strength was 3.22 MPa and the bending strength retention was 97.3%.

[Comparative Example 1]
A ceiling material for water use (prototype 4) was obtained in the same manner as in Example 2 except that the heating temperature of the thermocompression bonding belt was 160 ° C. and the surface temperature was 140 ° C. (Comparative Example 1). The amount of water absorption and the bending strength before and after water absorption were evaluated in the same manner as in Examples 1 to 3.
As shown in Table 2, the resulting open cell rate of the substrate prototype 4 33.1% grammage 700 g / ^{m 2,} the water absorption amount 953 g / ^{m 2,} before water absorption flexural strength 3.55 MPa, bending after water absorption The strength was 3.48 MPa, and the bending strength retention was 98.0%.
In Comparative Example 1 having an open cell ratio higher than 25.0%, the water absorption amount could not be suppressed.

[Comparative Examples 2-3]
In Comparative Examples 2 to 3 in which the gypsum board having the configuration, weighing, and thickness shown in Table 2 was used as a test piece, the water absorption amount and the bending strength before and after water absorption were evaluated in the same manner as in Examples 1 to 3. The results are shown in Table 2.
In Comparative Examples 1 and 2 in which a gypsum board was used as a test piece, all had a large water absorption amount of 2000 g / m ² or more.
Regarding the bending strength retention, all of Examples 1 to 3 were 95% or more, while Comparative Examples 1 and 2 were all 35% or less.

[Comparative Examples 4 to 6]
In Comparative Example 4 in which the fiber mixed calcium silicate was used as a test piece, Comparative Example 5 in which a rock wool decorative sound absorbing plate was used as a test piece, and Comparative Example 6 in which a nonwoven fabric was used as a test piece, water absorption was performed in the same manner as in Examples 1 to 3. The amount and bending strength before and after water absorption were evaluated. The results are shown in Table 3. In Comparative Examples 4 to 6, the water absorption was a large value of 750 g / m ² or more.
Regarding the bending strength retention, Comparative Example 4 was 77.5%, Comparative Example 5 was 4.2%, and Comparative Example 6 was not measurable.

  From these results, it was found that the amount of water absorption can be further suppressed according to the pool ceiling material of the present invention.

DESCRIPTION OF SYMBOLS 1 Ceiling material for water around 10 Board | substrate 12 Decorative layer 14 Foamed resin layer 16 1st metal layer 18 2nd metal layer 20 1st adhesive bond layer 22 2nd adhesive bond layer 24 3rd adhesive bond layer

Claims (4)

A ceiling material for water circulation comprising a substrate having a foamed resin layer and a first metal layer provided on one surface of the foamed resin layer,
The said board | substrate is a ceiling material for water circumferences whose open cell ratio is 5-25%.   2. The ceiling material for water supply according to claim 1, wherein the substrate has a second metal layer provided on the other surface of the foamed resin layer.   The ceiling material for water supply of Claim 1 or Claim 2 which further has a decorative layer provided in the surface of said 1st metal layer.   The ceiling material for water supply of Claim 3 with which the said decorative layer is formed with the nonwoven fabric.

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