JP2024033845A - Flat deck and fire retardant partition structure - Google Patents

Abstract

To provide a flat deck and a fire retardant partition structure excellent in fire retardant property through suppression of shrinkage of filler inside of ribs upon fire.SOLUTION: A flat deck is provided with a flat part 11, ribs 12 (121,122) projected on one surface 11D of the flat part 11, and a filler 13 arranged inside of the ribs 12, wherein a ratio of a density at a boundary surface part of the ribs of the filler 13 to a density at a core part of the filler 13 is 1.01 or more and 1.20 or less.SELECTED DRAWING: Figure 1

Description

FIELD OF THE INVENTION The present invention relates to flat deck and fire compartment structures used in building structures.

Conventionally, flat decks are sometimes used to construct floors or roof structures of building structures such as reinforced concrete and steel reinforced concrete. The flat deck extends along the longitudinal direction, and has a plurality of ribs each having a cavity inside formed on the lower surface of the flat portion, and has a flat upper surface (see, for example, Patent Document 1). Flat decks are used in floor or roof structures, for example, as formwork for pouring concrete onto the top surface of a flat section.

In a building structure, a fireproof partition structure is sometimes formed by a facing material such as gypsum board. In order to prevent flames from spreading in the event of a fire, the fireproof compartment structure must ensure that no gaps are formed between the floor structure and the roof structure in order to ensure sound insulation and heat insulation for compartments other than the fireproof compartment structure. There is. For example, when a flat deck is installed on a floor structure, when partitioning materials for forming compartments such as a fire protection compartment structure are butted against the bottom surface of the flat deck, a gap is created between the floor structure and the partitioning material due to the cavity inside the ribs. can. Therefore, it is necessary to remove the ribs by cutting the flat deck in the areas where the partition materials are butted against each other. The work to remove the ribs would be done on site, for example, after concrete has been poured. When ribs are removed at a construction site, the construction is laborious and there are safety issues.

To solve this problem, a flat deck with filler inside the ribs has been proposed. When filled inside the flat deck as a filler, the cavities inside the ribs prevent gaps from forming between the floor structure and the partitioning material, and the work of removing the ribs can be omitted.

JP 2017-110453 Publication

However, in flat decks with fillers filled inside the ribs, the filler shrinks inside the ribs in the event of a fire, forming cavities inside the ribs, resulting in reduced fire protection. .

Therefore, the present invention can provide a flat deck and fireproof compartment structure that suppresses the shrinkage of the filling inside the ribs in the event of a fire and has excellent fireproofing properties.

The gist of the present invention is as follows.
[1] A flat portion, a rib protruding from one surface of the flat portion, and a filler provided inside the rib, the rib of the filler having a density corresponding to the density of the core portion of the filler. A flat deck in which the density ratio of the interface region is 1.01 or more and 1.20 or less.
[2] The flat deck according to [1], wherein the filler is a foam.
[3] The flat deck according to [1] or [2], wherein the filling is an organic foam.
[4] The flat deck according to [3], wherein the organic foam is urethane foam.
[5] The flat deck according to [4], wherein the density of the core portion of the urethane foam is 20 kg/m ³ or more and 75 kg/m ³ or less.
[6] The flat deck according to [4] or [5], wherein the density of the rib interface portion of the urethane foam is 23 kg/m ³ or more and 80 kg/m ³ or less.
[7] The filling conforms to ISO 5660-1, and in a heat generation test using a cone calorimeter tester, the total calorific value for 20 minutes after the start of heating at a radiant heat intensity of 50 kW/m ² is 8 MJ/m ² or less. The flat deck according to any one of [1] to [6].
[8] The flat deck according to any one of [1] to [7], wherein the rib has an injection port for injecting the filler in a bottom portion.
[9] A fireproof compartment structure comprising the flat deck according to any one of [1] to [8], and a noncombustible material filling between the ribs on one surface of the flat portion of the flat deck.

According to the present invention, it is possible to provide a flat deck and a fireproof compartment structure that suppress shrinkage of the filling inside the ribs in the event of a fire and have excellent fireproofing properties.

FIG. 1(a) is a plan view of the front side showing a flat deck according to an embodiment of the present invention, and FIG. 1(b) is a sectional view taken along the line AA in FIG. 1(a). FIG. 2 is a sectional view showing a connected state of the flat deck according to the embodiment of the present invention. It is a top view of the back side which shows the flat deck based on embodiment of this invention. 1 is a sectional view showing a fire protection compartment structure according to an embodiment of the present invention.

As shown in FIGS. 1(a) and 1(b), the flat deck 1 according to the embodiment of the present invention includes a flat portion 11 and a rib that protrudes from one surface 11D of the flat portion 11 and has a hollow inside. 12 (12 ₁ , 12 ₂ ), and a filler 13 provided inside the rib 12.

In the flat deck 1, the upper surface 11U of the flat portion 11 is a flat surface, or minute irregularities are formed on the flat surface, and the lower surface 11D of the flat portion 11 is provided with a plurality of ribs 12 ₁ and 12 ₂ protruding. The plurality of ribs 12 ₁ and 12 ₂ are arranged along the lateral direction (X-axis direction in FIG. 1). Note that although FIG. 1 typically shows an example in which two ribs are provided, the number of ribs is not particularly limited. Each of the ribs 12 ₁ and 12 ₂ is a protrusion having a hollow inside, and extends in the vertical direction (Y-axis direction in FIG. 1). Both ends in the longitudinal direction of each rib 12 are configured to be closed, and may be closed by being crushed or may be configured to use a closing member. Note that the flat deck 1 can be obtained, for example, by roll forming or press forming a metal plate such as a steel plate or other materials.

As shown in FIG. 1(b), the cross-sectional shape of the rib 12 of the flat deck 1 includes a hollow portion 12a having a hollow formed therein, and a connecting portion 12b connecting the lower surface 11D and the hollow portion 12a. The cross-sectional shape of the cavity formed by the cavity portion 12a is not particularly limited, and can take various shapes such as a triangle, a square, and a circle, as long as a cavity is formed inside. The connecting portion 12b is narrowed in width from the hollow portion 12a and is arranged so that a pair of plate-like portions are brought together, and each plate-like portion connects the upper end of the hollow portion 12a to the lower surface 11D.

The flat deck 1 includes a claw portion 14 that projects from one surface 11D of the flat portion 11 and connects to the rib 12 of the flat deck that is arranged adjacently. The claw portion 14 is provided at the side end portion 18A of the flat portion 11. The claw portion 14 is formed by, for example, bending the flat portion 11. The claw portion 14 can be fitted into the connecting portion 12b of the flat deck 1 arranged adjacently. As shown in FIG. 2, the flat deck 1 is inserted into and fitted into the connecting part 12b of the flat deck 1 arranged adjacently, so that the flat deck 1 It is possible to connect them together. Note that, as shown in FIG. 2, the claw portion 14 is inserted and fitted into the gap between the pair of plate portions from the upper opening between the pair of plate portions that constitute the connecting portion 12b.
Note that the flat deck 1 may not include the claw portion 14, and for example, a plurality of flat decks 1 may be arranged side by side without being connected. Moreover, the flat deck 1 does not need to be plural, and may be used alone.

In this embodiment, the filler 13 is preferably a foam. By using foam as the filler 13, the specific gravity is light and the overall weight of the building material can be reduced. The foam used for the filler 13 is preferably an organic foam. The organic foam of the filler 13 is preferably one selected from the group consisting of polyolefin foams such as urethane foam, phenol foam, styrene foam, PVC foam, and polyethylene foam, among which urethane foam and phenol foam are preferred. It is more preferable that it is either one of these, and urethane foam is even more preferable. Moreover, examples of foams (inorganic foams) other than organic foams include water glass, foamed concrete, and the like.

The filler 13 consists of a rib interface region 13b as a skin layer, which is an interface with the inner surface of the rib 12, and a core region 13a excluding the rib interface region 13b. The rib interface portion 13b and the core portion 13a are provided within the cavity portion 12b.
In the filling material 13, the ratio of the density of the rib interface region 13b of the filling material 13 to the density of the core region 13a of the filling material 13 (density of the rib interface region/density of the core region) is 1.01 or more and 1.20 or less. . If the ratio of the density of the rib interface region 13b to the density of the core region 13a of the filler 13 is less than 1.01, it becomes difficult to form the filler 13 by injection. Further, if the ratio of the density of the rib interface area 13b to the density of the core area 13a of the filling material 13 is more than 1.20, there may be a large density difference between the core area 13a of the filling material 13 and the rib interface area 13b, or Shrinkage occurs due to insufficient adhesion, reducing fire protection in the event of a fire. The ratio of the density of the rib interface part 13b to the density of the core part 13a of the filling material 13 is 1.02 or more, from the viewpoint of ease of manufacture and from the viewpoint of suppressing shrinkage of the filling material 13 inside the rib 12 in the event of a fire. It is preferably .19 or less, more preferably 1.04 or more and 1.18 or less, and even more preferably 1.06 or more and 1.17 or less.

When the filling 13 is urethane foam, the density of the core region 13a is not particularly limited, but is preferably 20 kg/m ³ or more and 75 kg/m ³ or less, and 25 kg/m ³ or more and 70 kg/m ³ or less. More preferably, the weight is 30 kg/m ³ or more and 65 kg/m ³ or less. By setting the density of the core portion 13a of the filling material 13 to be less than or equal to the above upper limit value, the filling material 13 becomes lightweight, and the load on the building structure can be reduced. Further, by setting the density of the core portion 13a of the filler 13 to be equal to or higher than the above lower limit value, desired flame retardance and noncombustibility can be easily exhibited.
The density of the core region 13a can be measured in accordance with JIS K7222:2005.

When the filling 13 is urethane foam, the density of the rib interface portion 13b is not particularly limited, but is preferably 23 kg/m ³ or more and 80 kg/m ³ or less, and preferably 28 kg/m ³ or more and 76 kg/m ³ or less. It is more preferable that the weight is 33 kg/m ³ or more and 74 kg/m ³ or less. By setting the density of the filler 13 within the above range of the rib interface portion 13b, shrinkage of the filler 13 inside the rib 12 in the event of a fire can be easily suppressed.
The density of the rib interface portion 13b can be measured in accordance with JIS K7222:2005.

The density of the core region 13a and the rib interface member 13b is adjusted by controlling the formulation of the urethane resin composition for forming the urethane foam as the filler 13, the injection amount of the urethane resin composition, and the temperature of the ribs. can do. Specifically, by increasing the blending amount of the blowing agent and catalyst in the urethane resin composition, the density of the entire filler 13 can be lowered, and by increasing the blending amount of the inorganic filler or fixed flame retardant. This can increase the density of the entire filling 13. In addition, by reducing the amount of urethane resin composition injected into the ribs, the density, especially the density of the rib interface region 13b, can be lowered, and by increasing the amount of injection, the density, especially the density of the rib interface region 13b, can be increased. be able to. In addition, by increasing the temperature of the ribs when injecting the urethane resin composition, foaming can be promoted and the density, especially the density of the rib interface area 13b, can be lowered, and by lowering the temperature of the ribs, the density, especially the rib The density of the interface region 13b can be increased.

As will be described later, the foam as the filler 13 is generally injected into the cavity 12a of the rib ₁₂₁ and foamed to fill it.
The filling material 13 may or may not be filled in the connecting portion 12b of the rib 121 as long as it is filled inside the cavity portion _12a , or may be filled only partially. It is preferable that an unfilled portion 15 in which the filler 13 is not filled is provided in a part of the portion 12b. When the unfilled portion 15 is provided, by fitting the claw portion 14 into the unfilled portion 15, it is possible to connect the pair of flat decks while filling the hollow portion 12a of the rib ₁₂₁ with the filler 13. become. Therefore, the flat deck can be connected to other flat decks using the ribs, and can also have excellent fire protection.

Here, the filler 13 may not fill the entire gap between the connecting portions 12b, and the entire gap between the connecting portions 12b may be an unfilled portion 15, or the claw portions 14 can be fitted into the connecting portions 12b. As far as possible, the unfilled portion 15 may be part of the gap between the connecting portions 12b of the ribs ₁₂₁ .
Among the plurality of ribs 12 ₁ and 12 ₂ whose cavities are filled with filler, there is an unfilled portion 15 that is not filled with filler in the connecting portion 12 b of at least one rib 12 ₁ into which the claw portion 14 is fitted. For example, it is preferable that the unfilled portion 15 be provided at least in the rib provided closest to the side end 18B.

Furthermore, each of the ribs 12 ₁ and 12 ₂ has, for example, an injection port 16 (see FIG. 3) on the bottom surface for injecting a filler. The ribs 12 ₁ , 12 ₂ have injection ports 16 at the bottom, so that the filler 13 can be injected from the bottom and spread throughout the cavity 12 a of the ribs, and the filling 13 can be injected from the bottom to the entire cavity of the rib cavity 12 a. It becomes difficult for the filler to penetrate into the gap 12b.
In addition, in the case of a triangular or quadrangular shape as shown in Fig. 1, the bottom surface portion is preferably the surface that constitutes the bottom surface of the rib, but in structures other than a triangular or square shape such as a circle, the bottom surface portion is the portion that can be seen from the bottom surface side. This is the bottom part.
Moreover, one injection port 16 may be provided in each rib, or two or more injection ports 16 may be provided in each rib.

The filler 13 is preferably made of a fire-resistant material from the viewpoint of improving fire protection. Fire-resistant materials refer to materials that exhibit performance equivalent to flame-retardant materials specified in the Building Standards Act and the Building Standards Act Enforcement Order (hereinafter referred to as "flame-retardant materials"). (hereinafter referred to as "semi-noncombustible material"), and more preferably a material that exhibits performance equivalent to that of a noncombustible material (hereinafter referred to as "noncombustible material"). Performance equivalent to flame retardant material is based on ISO5660-1, and in a heat generation test using a cone calorimeter tester, when heated at a radiant heat intensity of 50 kW/ ^m2 , the total calorific value after 5 minutes has elapsed. 8MJ/ ^m2 or less. Furthermore, the performance equivalent to a quasi-noncombustible material means that the total calorific value after 10 minutes is 8 MJ/m ² or less. Furthermore, the performance equivalent to that of a noncombustible material means that the total calorific value after 20 minutes is 8 MJ/m ² or less.

The organic foam such as urethane foam as the filler 13 only needs to have performance equivalent to at least one of a flame retardant material, a quasi-nonflammable material, and a noncombustible material, and has performance equivalent to a noncombustible material. It is preferable. When measuring organic foam according to the ISO-5660 test method, prepare a test sample by cutting the organic foam into 10 cm long, 10 cm wide, and 5 cm thick, and use the test sample to cut the organic foam into a cone. Perform a heat generation test using a calorimeter tester.

<Flat deck manufacturing method>
Hereinafter, a method for manufacturing a flat deck according to this embodiment will be explained.
The method for manufacturing a flat deck according to the present embodiment includes a flat part 11, a rib 12 protruding from one surface 11D of the flat part 11, and a filler 13 provided inside the rib 12. This is a method for manufacturing a flat deck in which the ratio of the density of the rib interface region 13b of the filler 13 to the density of the core region 13a of the material 13 is 1.01 or more and 1.20 or less. The method for manufacturing a flat deck according to the present embodiment preferably includes a step of filling the inside of the rib 12 with the filler 13 while heating the rib 12 .
Hereinafter, a method for manufacturing a flat deck according to a preferred embodiment will be described in more detail.

In the first manufacturing method of a flat deck according to the present embodiment, first, a rib 12 (cavity part 12a, connecting part 12b) that protrudes from one surface 11D of the flat part 11 and has a cavity inside is formed. Bending the material in this way. Next, the connecting portion 12b of the rib 12 forming the unfilled portion 15 is pressed from both sides to eliminate the gap. Next, in a state in which the connecting portion 12b is pressed from both sides to eliminate the gap, and the rib 12 is heated by a heating device such as a heater, from the injection port 16 formed in the bottom portion of the cavity 12a of the rib 12. A material for the filler 13 is injected to fill the cavity 12a with the filler 13. The heating device is not particularly limited as long as it is a device that can heat the rib 12 from the outer peripheral surface side, and includes, for example, a contact type heater such as a contact type rubber heater, a far infrared heater, a gas heater, an oil heater, and the like.

As described above, by increasing the temperature of the rib 12 when injecting the material for the filler 13, the density of the rib interface region 13b can be lowered. Although the rib interface region 13b tends to have a higher density than the core region 13a, by heating the rib 12, the difference in density between the rib interface region 13b and the core region 13a can be reduced. The temperature of the rib 12 when injecting the material for the filler 13 is preferably 25°C or more and 110°C or less, more preferably 30°C or more and 100°C or less, and 35°C or more and 90°C or less. is even more preferable.

The flat deck 1 formed through the above steps is filled with the filler 13 that reacts uniformly inside the ribs 12 by introducing the material for the filler 13 from the injection port 16 while the ribs 12 are heated. Can be done. By this, the properties of the core region 13a and the rib interface region 13b of the filler 13 inside the rib 12 can be controlled, and the ratio of the density of the rib interface region 13b to the density of the core region 13a of the filler 13 can be controlled. can do.

In the above process, when heating the rib 12, it is preferable to heat the rib 12 so that the farther from the injection port 16 in the longitudinal direction of the rib 12, the higher the temperature becomes. The injection liquid into which the material of the filler 13 is introduced from the injection port 16 tends to cool down the farther from the injection port 16 and the reaction tends to become uneven in the longitudinal direction of the ribs 12. By heating in such a way that cooling at a distant place can be prevented, and the reaction can be made more uniform.
However, it is not necessarily necessary to heat the ribs 12 so that the temperature increases as the distance from the injection port 16 increases, and the ribs 12 may be heated almost uniformly in the longitudinal direction of the ribs 12.

Further, in the flat deck 1 formed through the above steps, after filling the cavity 12a with the filler 13, the pressure from both sides of the connecting portion 12b is released, so that the connecting portion 12b is filled with the filler 13. First, an unfilled portion 15 is formed in which the connecting portion 12b can fit into the claw portion 14. However, it is also possible to fill the connecting portion 12b with the filler 13 by reducing the pressure applied from both sides of the connecting portion 12b in this step and by not applying pressure.

<Urethane foam>
The urethane foam constituting the filling 13 will be explained in more detail. The urethane foam used in this embodiment is formed by curing and foaming a urethane resin composition. The urethane resin contained in the urethane foam is a reaction product obtained by mixing and reacting a polyisocyanate compound and a polyol compound. The urethane resin composition is in a liquid state immediately after being prepared by mixing various components so that it can be easily injected into the inside of the rib 12 and can fill the cavity 12a of the rib 12 without any gaps.
As a method for applying the urethane foam to fill and close the cavity 12a of the rib 12, discharge filling using a discharge device that discharges a liquid urethane resin composition is suitable. Note that, for example, when the urethane resin composition is a two-component curing type, the dispensing device includes a mixing section that mixes the first and second components, and a discharge device that dispenses the mixed urethane resin composition. Use one with an exit. As such a discharging device, a high-pressure foaming machine, a low-pressure foaming machine, other mixing/discharging systems, spray guns, caulking guns, etc. may be used.

The urethane resin composition that forms urethane foam generally contains a polyisocyanate compound and a polyol compound.
Examples of the polyisocyanate compound used in the urethane foam include aromatic polyisocyanates, alicyclic polyisocyanates, aliphatic polyisocyanates, and the like.
Examples of the aromatic polyisocyanate include phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, dimethyldiphenylmethane diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate, and polymethylene polyphenyl polyisocyanate.

Examples of the alicyclic polyisocyanate include cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and dimethyldicyclohexylmethane diisocyanate.
Examples of the aliphatic polyisocyanate include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, and the like.
The polyisocyanate compounds may be used alone or in combination of two or more.
As the polyisocyanate compound, diphenylmethane diisocyanate (MDI) is preferred because it is easy to use and easy to obtain.

Examples of the polyol compound include polylactone polyol, polycarbonate polyol, aromatic polyol, alicyclic polyol, aliphatic polyol, polyester polyol, polymer polyol, polyether polyol, and the like.
Examples of polylactone polyols include polypropiolactone glycol, polycaprolactone glycol, polyvalerolactone glycol, and the like.
Examples of polycarbonate polyols include polyols obtained by dealcoholization reaction of hydroxyl group-containing compounds such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, octanediol, and nonanediol with diethylene carbonate, dipropylene carbonate, etc. etc.

Examples of aromatic polyols include bisphenol A, bisphenol F, phenol novolak, and cresol novolak.
Examples of the alicyclic polyol include cyclohexanediol, methylcyclohexanediol, isophoronediol, dicyclohexylmethanediol, and dimethyldicyclohexylmethanediol.
Examples of aliphatic polyols include ethylene glycol, propylene glycol, butanediol, pentanediol, and hexanediol.

Examples of polyester polyols include polymers obtained by dehydration condensation of polybasic acids and polyhydric alcohols, polymers obtained by ring-opening polymerization of lactones such as ε-caprolactone and α-methyl-ε-caprolactone, Examples include condensates of hydroxycarboxylic acids and the above-mentioned polyhydric alcohols.
Here, specific examples of the polybasic acid include adipic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, and succinic acid. Specific examples of the polyhydric alcohol include bisphenol A, ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, diethylene glycol, 1,6-hexane glycol, and neopentyl glycol. .
Further, specific examples of the hydroxycarboxylic acid include castor oil, a reaction product of castor oil and ethylene glycol, and the like.

Examples of polymer polyols include polymers obtained by graft polymerizing ethylenically unsaturated compounds such as acrylonitrile, styrene, methyl acrylate, and methacrylate to the above-mentioned aromatic polyols, alicyclic polyols, aliphatic polyols, polyester polyols, etc. , polybutadiene polyol, modified polyol of polyhydric alcohol, or hydrogenated products thereof.
Examples of modified polyols of polyhydric alcohols include those obtained by reacting polyhydric alcohols as raw materials with alkylene oxide to modify them.
Examples of the polyhydric alcohol used in the modified polyol include trihydric alcohols such as glycerin and trimethylolpropane, pentaerythritol, sorbitol, mannitol, sorbitan, diglycerin, dipentaerythritol, sucrose, glucose, mannose, fructose, Tetra- to octavalent alcohols such as methyl glucoside and its derivatives, phenol, phloroglucin, cresol, pyrogallol, catechol, hydroquinone, bisphenol A, bisphenol F, bisphenol S, 1-hydroxynaphthalene, 1,3,6,8-tetrahydroxy Phenols such as naphthalene, anthrol, 1,4,5,8-tetrahydroxyanthracene, and 1-hydroxypyrene, polybutadiene polyols, castor oil polyols, polymers or copolymers of hydroxyalkyl (meth)acrylates, and polyvinyl alcohols. Examples include functional (for example, functional group number 2 to 100) polyols and condensates of phenol and formaldehyde (novolak).

Although the method for modifying the polyhydric alcohol is not particularly limited, a method of adding alkylene oxide (hereinafter abbreviated as AO) is preferably used.
Examples of AO include AO having 2 to 6 carbon atoms, such as ethylene oxide (hereinafter abbreviated as EO), 1,2-propylene oxide (hereinafter abbreviated as PO), 1,3-propyleoxide, 1,2- Examples include butylene oxide and 1,4-butylene oxide.
Among these, from the viewpoint of properties and reactivity, PO, EO and 1,2-butylene oxide are preferred, and PO and EO are more preferred.
When two or more types of AO are used (for example, PO and EO), the addition method may be block addition, random addition, or a combination of these.

For example, the polyether polyol is prepared by ring-opening polymerization of at least one alkylene oxide such as ethylene oxide, propylene oxide, and tetrahydrofuran in the presence of at least one low molecular weight active hydrogen compound having two or more active hydrogens. Examples include the resulting polymers.
Examples of low molecular weight active hydrogen compounds having two or more active hydrogens used in polyether polyols include diols such as bisphenol A, ethylene glycol, propylene glycol, butylene glycol, and 1,6-hexanediol, glycerin, and trimethylol. Examples include triols such as propane, and amines such as ethylene diamine and butylene diamine.

As the polyol used in the urethane foam, it is preferable to use a polyester polyol or a polyether polyol, and a polyester polyol is more preferable, since it has a large effect of reducing the total calorific value when burned. Among these, it is preferable to use polyester polyols with a molecular weight of 200 to 800, and it is more preferable to use polyester polyols with a molecular weight of 300 to 500.

The isocyanate index of the urethane resin is preferably in the range of 120 to 1,000, more preferably in the range of 200 to 800, and even more preferably in the range of 300 to 600. When the isocyanate index is 120 or more, the isocyanate groups will be in excess of the hydroxyl groups and will be more likely to be trimerized, making it easier to impart nonflammability. Moreover, when it is 1,000 or less, the balance between nonflammability and manufacturing cost becomes good.

Note that the isocyanate index can be calculated by the following method.
Isocyanate index = number of equivalents of polyisocyanate ÷ (number of equivalents of polyol + number of equivalents of water) x 100
Here, each equivalent number can be calculated as follows.
- Number of equivalents of polyisocyanate = amount of polyisocyanate used (g) x NCO content (mass%) / molecular weight of NCO (mol) x 100
・Number of equivalents of polyol = OHV x amount of polyol used (g) ÷ molecular weight of KOH (mmol)
OHV is the hydroxyl value (mgKOH/g) of the polyol.
- Number of equivalents of water = amount of water used (g) / molecular weight of water (mol) x number of OH groups in water In each of the above formulas, the molecular weight of NCO is 42 (mol), the molecular weight of KOH is 56100 (mmol), The molecular weight of water is 18 (mol), and the number of OH groups in water is 2.

"Flame retardants"
In order to impart a flame retardant effect to the urethane foam, it is preferable to contain a flame retardant, and examples include the use of liquid flame retardants such as phosphoric acid esters. As the flame retardant, in order to improve flame retardancy, it is also preferable to use a solid flame retardant, and it is also preferable to use a solid flame retardant and a liquid flame retardant in combination.
Liquid flame retardants are flame retardants that become liquid at room temperature (23°C) and normal pressure (1 atm), and solid flame retardants are flame retardants that become solid at room temperature (23°C) and normal pressure (1 atm). be. Specific examples of liquid flame retardants include phosphoric acid esters.
Examples of the solid flame retardant include at least one selected from red phosphorus, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides.
It is more preferable that the flame retardant used in the urethane foam contains red phosphorus and phosphoric acid ester from the viewpoint of nonflammability, ease of handling, and the like. Further, the flame retardant is composed of red phosphorus, phosphate ester, and at least one selected from phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides. is also preferable.

<Phosphate ester>
As the phosphoric acid ester, monophosphoric acid ester, condensed phosphoric acid ester, etc. can be used. A monophosphoric acid ester is a phosphoric acid ester having one phosphorus atom in the molecule. Monophosphoric acid esters are not limited as long as they are liquid at room temperature and pressure, but examples include trialkyl phosphates such as trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri(2-ethylhexyl) phosphate, and tris(β-chloro). halogen-containing phosphate esters such as propyl) phosphate, trialkoxy phosphates such as tributoxyethyl phosphate, tricresyl phosphate, tricylenyl phosphate, tris(isopropylphenyl) phosphate, cresyl diphenyl phosphate, diphenyl (2-ethylhexyl) phosphate Acidic phosphoric esters such as aromatic ring-containing phosphoric acid esters such as monoisodecyl phosphate and diisodecyl phosphate are included.

Examples of the condensed phosphoric acid ester include aromatic condensed phosphoric acid esters such as trialkyl polyphosphate, resorcinol polyphenyl phosphate, bisphenol A polycresyl phosphate, and bisphenol A polyphenyl phosphate.
Commercially available condensed phosphate esters include, for example, resorcinol polyphenyl phosphate (trade name CR-733S), bisphenol A polycresyl phosphate (trade name CR-741), aromatic condensed phosphate ester (trade name CR747), and resorcinol. Examples include polyphenyl phosphate (manufactured by ADEKA, trade name ADEKA STAB PFR), bisphenol A polycresyl phosphate (trade names FP-600, FP-700), and the like.

Among the above, it is preferable to use monophosphoric acid ester because it has a high effect of reducing the viscosity in the composition before curing and the effect of reducing the initial calorific value, and tris (β-chloropropyl) phosphate is preferably used. is more preferable. The phosphoric acid esters may be used alone or in combination of two or more.

The amount of phosphoric acid ester blended is preferably in the range of 1.5 to 52 parts by weight, more preferably in the range of 1.5 to 20 parts by weight, based on 100 parts by weight of the urethane resin.2. The range is more preferably from 0 to 15 parts by weight, and most preferably from 2.0 to 10 parts by weight.
By setting the amount of phosphoric acid ester to be at least the above lower limit, it is possible to prevent the dense residue formed from the urethane foam from cracking in the event of a fire. Further, by setting the amount of the phosphoric acid ester to be less than or equal to the above upper limit value, foaming of the urethane resin composition is not inhibited. Moreover, by setting it within the above range, it becomes easy to impart nonflammability.

<Red phosphorus>
The red phosphorus used in the present invention is not limited, and commercially available products can be appropriately selected and used. Red phosphorus does not need to be blended alone, and may be surface-treated as appropriate.
The amount of red phosphorus blended in the urethane foam is preferably in the range of 3.0 to 18 parts by weight, more preferably 4.0 to 12 parts by weight, based on 100 parts by weight of the urethane resin. By setting the amount of red phosphorus to be equal to or higher than the above lower limit, the self-extinguishing property of the urethane foam is maintained, and it becomes easier to impart nonflammability to the urethane foam. Furthermore, by setting the amount of red phosphorus to be less than or equal to the above upper limit, foaming of the urethane resin composition is not inhibited. As mentioned above, the urethane resin is a reaction product of a polyisocyanate compound and a polyol compound, and 100 parts by mass of the urethane resin means a total of 100 parts by mass of the polyisocyanate compound and the polyol compound in the urethane resin composition. do.

<Phosphate-containing flame retardant>
Phosphate-containing flame retardants include, for example, phosphoric acid salts of various phosphoric acids and at least one metal or compound selected from metals of Groups IA to IVB of the Periodic Table, ammonia, aliphatic amines, and aromatic amines. Mention may be made of acid salts.
The phosphoric acid is not particularly limited, but various phosphoric acids such as monophosphoric acid, pyrophosphoric acid, and polyphosphoric acid can be mentioned.
Examples of metals in Groups IA to IVB of the periodic table include lithium, sodium, calcium, barium, iron (II), iron (III), aluminum, and the like. Examples of aliphatic amines include methylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, piperazine, and the like. Further, examples of aromatic amines include pyridine, triazine, melamine, ammonium, and the like.
In addition, the above-mentioned phosphate-containing flame retardant may be subjected to known water resistance improvement treatments such as silane coupling agent treatment and coating with melamine resin.

Specific examples of phosphate-containing flame retardants include monophosphates, pyrophosphates, polyphosphates, and the like.
Monophosphates are not particularly limited, but include, for example, ammonium salts such as ammonium phosphate, ammonium dihydrogen phosphate, and ammonium hydrogen phosphate, monosodium phosphate, disodium phosphate, trisodium phosphate, and phosphorous acid. Sodium salts such as monosodium, disodium phosphite, sodium hypophosphite, monopotassium phosphate, dipotassium phosphate, tripotassium phosphate, monopotassium phosphite, dipotassium phosphite, hypophosphorous acid Potassium salts such as potassium, monolithium phosphate, dilithium phosphate, trilithium phosphate, monolithium phosphite, dilithium phosphite, lithium hypophosphite, etc., barium dihydrogen phosphate, phosphorus Barium salts such as barium oxyhydrogen, tribarium phosphate, barium hypophosphite, magnesium salts such as monohydrogen phosphate, magnesium hydrogen phosphate, trimagnesium phosphate, magnesium hypophosphite, calcium dihydrogen phosphate , calcium salts such as calcium hydrogen phosphate, tricalcium phosphate, and calcium hypophosphite; zinc salts such as zinc phosphate, zinc phosphite, and zinc hypophosphite.

Further, the polyphosphate is not particularly limited, but examples thereof include ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium amide polyphosphate, aluminum polyphosphate, and the like.
Among these, monophosphates are preferably used, and ammonium dihydrogen phosphate is more preferably used, since the self-extinguishing properties of phosphate-containing flame retardants are improved.
The phosphate-containing flame retardants may be used alone or in combination of two or more.

The blending amount of the phosphate-containing flame retardant is preferably in the range of 1.5 to 52 parts by mass, more preferably in the range of 1.5 to 20 parts by mass, based on 100 parts by mass of the urethane resin. , more preferably in the range of 2.0 to 15 parts by weight, and most preferably in the range of 2.0 to 10 parts by weight.
When the amount of the phosphate-containing flame retardant is at least the above lower limit, the self-extinguishing properties of the urethane foam are maintained and fire resistance is easily imparted. Further, when the amount of the phosphate-containing flame retardant is equal to or less than the above upper limit, foaming of the urethane resin composition is not inhibited.

<Bromine-containing flame retardant>
The bromine-containing flame retardant is not particularly limited as long as it is a compound containing bromine in its molecular structure, and examples thereof include aromatic brominated compounds.
Specific examples of aromatic brominated compounds include hexabromobenzene, pentabromotoluene, hexabromo biphenyl, decabromo biphenyl, hexabromocyclodecane, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis(pentabromo Examples include monomeric organic bromine compounds such as phenoxy)ethane, ethylene-bis(tetrabromophthalimide), and tetrabromobisphenol A.
In addition, polycarbonate oligomers produced using brominated bisphenol A as a raw material, brominated polycarbonates such as copolymers of polycarbonate oligomers and bisphenol A, diepoxy compounds produced by the reaction of brominated bisphenol A and epichlorohydrin, and brominated phenols. brominated epoxy compounds such as monoepoxy compounds obtained by the reaction of brominated epoxy compounds with epichlorohydrin, poly(brominated benzyl acrylate), brominated polyphenylene ether, brominated bisphenol A, condensates of cyanuric chloride and brominated phenol, brominated ( Brominated polystyrene such as polystyrene), poly(brominated styrene), crosslinked brominated polystyrene, and halogenated bromine compound polymers such as crosslinked or non-crosslinked brominated poly(-methylstyrene).
From the viewpoint of controlling the calorific value at the initial stage of combustion, brominated polystyrene, hexabromobenzene, etc. are preferable, and hexabromobenzene is more preferable.
Bromine-containing flame retardants may be used alone or in combination of two or more.

The amount of the bromine-containing flame retardant used in the present invention is preferably in the range of 1.5 to 50 parts by mass, and preferably in the range of 1.5 to 20 parts by mass, based on 100 parts by mass of the urethane resin. It is more preferably in the range of 2.0 to 15 parts by weight, and most preferably in the range of 2.0 to 10 parts by weight.
When the amount of the bromine-containing flame retardant is greater than or equal to the above lower limit, the self-extinguishing properties of the urethane foam are maintained and fire resistance is easily imparted. Further, when the amount of the bromine-containing flame retardant is equal to or less than the above upper limit, foaming of the urethane resin composition is not inhibited.

<Boron-containing flame retardant>
Examples of boron-containing flame retardants include borax, boron oxide, boric acid, and borates.
Examples of boron oxide include diboron trioxide, boron trioxide, diboron dioxide, tetraboron trioxide, and tetraboron pentoxide.
Examples of borates include borates of alkali metals, alkaline earth metals, elements of Group 4, Group 12, and Group 13 of the periodic table, and ammonium.
Specifically, alkali metal borates such as lithium borate, sodium borate, potassium borate, and cesium borate; alkaline earth metal borates such as magnesium borate, calcium borate, and barium borate; Examples include zirconium acid, zinc borate, aluminum borate, ammonium borate, and the like.
The boron-containing flame retardant is preferably a borate, more preferably zinc borate.
Boron-containing flame retardants may be used alone or in combination of two or more.

The blending amount of the boron-containing flame retardant is preferably in the range of 1.5 to 50 parts by mass, more preferably in the range of 1.5 to 20 parts by mass, based on 100 parts by mass of the urethane resin. The range is more preferably from .0 to 15 parts by weight, and most preferably from 2.0 to 10 parts by weight.
When the amount of the boron-containing flame retardant is at least the above lower limit, the self-extinguishing properties of the urethane foam are maintained and fire resistance is easily imparted. Further, when the amount of the boron-containing flame retardant is equal to or less than the above upper limit, foaming of the urethane resin composition is not inhibited.

<Antimony-containing flame retardant>
Examples of the antimony-containing flame retardant used in the present invention include antimony oxide, antimonate salts, and pyroantimonate salts.
Examples of antimony oxide include antimony trioxide and antimony pentoxide. Examples of antimonate salts include sodium antimonate, potassium antimonate, and the like. Examples of the pyroantimonate include sodium pyroantimonate and potassium pyroantimonate.
Preferably, the antimony-containing flame retardant is antimony oxide.
Antimony-containing flame retardants may be used alone or in combination of two or more.

The blending amount of the antimony-containing flame retardant is preferably in the range of 1.5 to 50 parts by mass, more preferably in the range of 1.5 to 20 parts by mass, based on 100 parts by mass of the urethane resin. The range is more preferably from .0 to 15 parts by weight, and most preferably from 2.0 to 10 parts by weight. When the amount of the antimony-containing flame retardant is at least the above lower limit, the self-extinguishing properties of the urethane foam are maintained and fire resistance is easily imparted. Further, when the amount of the antimony-containing flame retardant is below the above upper limit, foaming of the urethane resin composition is not inhibited.

<Metal hydroxide>
Examples of metal hydroxides include magnesium hydroxide, calcium hydroxide, aluminum hydroxide, iron hydroxide, nickel hydroxide, zirconium hydroxide, titanium hydroxide, zinc hydroxide, copper hydroxide, vanadium hydroxide, and water. Examples include tin oxide. The metal hydroxides may be used alone or in combination of two or more.

The blending amount of the metal hydroxide is preferably in the range of 1.5 to 50 parts by mass, more preferably in the range of 1.5 to 20 parts by mass, based on 100 parts by mass of the urethane resin. The range is more preferably from .0 to 15 parts by weight, and most preferably from 2.0 to 10 parts by weight. When the amount of the metal hydroxide is at least the above lower limit, the self-extinguishing properties of the urethane foam are maintained and fire resistance is easily imparted. Further, since the amount of metal hydroxide is below the above upper limit, foaming of the urethane resin composition is not inhibited.

Preferred combinations of the above flame retardants include, for example, any of the following (a) to (n), among which combinations containing at least red phosphorus and phosphoric acid ester are preferred.
(a) Red phosphorus and phosphate esters (b) Flame retardants containing red phosphorus and phosphates (c) Flame retardants containing red phosphorus and bromine (d) Flame retardants containing red phosphorus and boron (e) Flame retardants containing red phosphorus and antimony Flame retardants (f) Red phosphorus and metal hydroxides (g) Flame retardants containing red phosphorus, phosphate esters and phosphates (h) Flame retardants containing red phosphorus, phosphate esters and bromine (i) Red phosphorus, phosphate esters and boron-containing flame retardants (j) red phosphorus, phosphate-containing flame retardants and bromine-containing flame retardants (k) red phosphorus, phosphate-containing flame retardants and boron-containing flame retardants (l) red phosphorus, bromine-containing flame retardants and Boron-containing flame retardants (m) Red phosphorus, phosphate esters, phosphate-containing flame retardants and bromine-containing flame retardants (n) Red phosphorus, phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants and boron-containing flame retardants fuel

The total blending amount of the solid flame retardant is preferably in the range of 4.5 to 70 parts by mass, more preferably in the range of 4.5 to 40 parts by mass, based on 100 parts by mass of the urethane resin. The range is more preferably from .5 to 30 parts by weight, and most preferably from 4.5 to 20 parts by weight.
When the amount of the solid flame retardant is greater than or equal to the above lower limit, it becomes easier to impart nonflammability to the urethane foam and increase the density of the urethane foam. Furthermore, it is possible to prevent the dense residue formed from urethane foam from cracking in the event of a fire. When the amount of the flame retardant is below the above upper limit, the foaming of the urethane resin composition is not inhibited by the flame retardant.

As described above, the urethane foam of the present invention is formed by curing and foaming a urethane resin composition. The urethane resin composition contains the above-mentioned polyol compound, isocyanate compound, and flame retardant, and generally further contains a catalyst, a blowing agent, and a foam stabilizer.

"catalyst"
The urethane resin composition may contain, for example, a resinization catalyst, a trimerization catalyst, or both, as a catalyst, and preferably contains both. The resinization catalyst is a catalyst that promotes the reaction between a polyol compound and a polyisocyanate.

The resinization catalyst is a catalyst that promotes the reaction between a polyol compound and a polyisocyanate. Examples of the resinization catalyst include amine catalysts such as imidazole compounds and piperazine compounds, and metal catalysts.
Examples of imidazole compounds include tertiary amines in which the secondary amine at position 1 of the imidazole ring is substituted with an alkyl group, an alkenyl group, or the like. Specifically, N-methylimidazole, 1,2-dimethylimidazole, 1-ethyl-2-methylimidazole, 1-methyl-2-ethylimidazole, 1,2-diethylimidazole, and 1-isobutyl-2-methyl Examples include imidazole. Alternatively, an imidazole compound in which the secondary amine in the imidazole ring is substituted with a cyanoethyl group may also be used.
Examples of the piperazine compound include tertiary amines such as N-methyl-N'N'-dimethylaminoethylpiperazine and trimethylaminoethylpiperazine.
In addition to imidazole compounds and piperazine compounds, examples of resin conversion catalysts include pentamethyldiethylenetriamine, triethylamine, N-methylmorpholine bis(2-dimethylaminoethyl)ether, N,N,N',N",N"- Pentamethyldiethylenetriamine, N,N,N'-trimethylaminoethyl-ethanolamine, bis(2-dimethylaminoethyl)ether, N,N-dimethylcyclohexylamine, diazabicycloundecene, triethylenediamine, tetramethylhexamethylenediamine , various tertiary amines such as tripropylamine, and the like.
Examples of the metal catalyst include metal salts selected from bismuth and tin, with bismuth salts being preferred.
The blending amount of the resin conversion catalyst is preferably in the range of 0.02 to 5 parts by mass, more preferably in the range of 0.04 to 3 parts by mass, and 0.02 to 5 parts by mass, more preferably 0.04 to 3 parts by mass, based on 100 parts by mass of the urethane resin. The range is more preferably from 0.04 to 2 parts by weight, and most preferably from 0.06 to 1 part by weight.
By setting the blending amount of the resin-forming catalyst to the above lower limit value or more, the formation of urethane bonds is promoted and the curability becomes good. Further, by setting the amount of the resinization catalyst to be less than or equal to the above upper limit value, an appropriate foaming rate can be maintained and it is easy to handle.

The trimerization catalyst is a catalyst that causes the isocyanate groups contained in the polyisocyanate compound to react and trimerize, thereby promoting the production of isocyanurate rings. By using a trimerization catalyst, it becomes easier to increase the rate of nurate formation, and it becomes easier to form a nurate foam that is desirable from the viewpoint of flame retardancy.
Trimerization catalysts include nitrogen-containing aromatic compounds such as tris(dimethylaminomethyl)phenol, 2,4-bis(dimethylaminomethyl)phenol, and 2,4,6-tris(dialkylaminoalkyl)hexahydro-S-triazine. , alkali metal carboxylates such as potassium acetate, potassium 2-ethylhexanoate, potassium octylate, tertiary ammonium salts such as trimethylammonium salt, triethylammonium salt, triphenylammonium salt, tetramethylammonium salt, tetraethylammonium, tetra Quaternary ammonium salts such as phenylammonium salts can be used.

The blending amount of the trimerization catalyst is preferably in the range of 0.6 to 10 parts by mass, more preferably in the range of 0.6 to 8 parts by mass, and 0.6 to 10 parts by mass, more preferably 0.6 to 8 parts by mass, based on 100 parts by mass of the urethane resin. It is more preferably in the range of 6 to 6 parts by weight, and most preferably in the range of 0.6 to 3.0 parts by weight.
When the blending amount of the trimerization catalyst is equal to or higher than the above lower limit value, the problem of inhibiting the trimerization of isocyanate does not occur, and the nurate rate of the urethane foam is improved to form a nurate foam that is desirable from the viewpoint of flame retardancy. It becomes easier to do. Further, when the amount of the trimerization catalyst is equal to or less than the above-mentioned upper limit, an appropriate foaming rate can be maintained and it is easy to handle.

《Foaming agent》
The foaming agent contained in the urethane resin composition promotes foaming of the urethane resin. Specific examples of blowing agents include water, low-boiling hydrocarbons such as propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, and cycloheptane, dichloroethane, propyl chloride, isopropyl chloride, Chlorinated aliphatic hydrocarbon compounds such as butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride, fluorine compounds such as trichloromonofluoromethane, trichlorotrifluoroethane, hydrocarbons such as CHF ₃ , CH ₂ F ₂ , CH ₃ F, etc. Fluorocarbon, dichloromonofluoroethane, (e.g. HCFC141b (1,1-dichloro-1-fluoroethane), HCFC22 (chlorodifluoromethane), HCFC142b (1-chloro-1,1-difluoroethane)), HFC-245fa (1 , 1,1,3,3-pentafluoropropane), HFC-365mfc (1,1,1,3,3-pentafluorobutane), HFO-1233zd(E) (trans-1- chloro-3,3,3-trifluoropropene), HFO-1234yf (2,3,3,3-tetrafluoro-1-propene), HFO-1336mzz(Z) (cis-1,1,1,4, 4,4,-hexafluorobut-2-ene), hydroolefin compounds such as HFO-1224yd (Z), ether compounds such as diisopropyl ether, or organic physical blowing agents such as mixtures of these compounds, nitrogen gas, Examples include inorganic physical blowing agents such as oxygen gas, argon gas, and carbon dioxide gas. Among these, it is preferable to use hydroolefin compounds from the viewpoint of protecting the global environment. Further, a hydroolefin compound and water may be used together.

The amount of the blowing agent used in the urethane resin composition is preferably in the range of 0.1 to 30 parts by weight based on 100 parts by weight of the urethane resin. Further, the blowing agent is more preferably in the range of 0.1 to 18 parts by mass, even more preferably in the range of 0.5 to 18 parts by mass, and even more preferably 1 to 10 parts by mass, based on 100 parts by mass of the urethane resin. Parts by weight are most preferred.
When the amount of the foaming agent is greater than or equal to the above lower limit, foaming is likely to be promoted. When the amount of the foaming agent is equal to or less than the above upper limit, it is possible to prevent the foam from breaking and forming a foam. By increasing the amount of the blowing agent within the above range, the density of the resulting urethane foam can be reduced. Moreover, the density of the urethane foam obtained can be increased by reducing the amount of the blowing agent within the above range.

《Foam stabilizer》
The foam stabilizer contained in the urethane resin composition improves the foamability of the urethane resin composition.
Examples of the foam stabilizer include surfactants such as polyoxyalkylene foam stabilizers such as polyoxyalkylene alkyl ether, and silicone foam stabilizers such as organopolysiloxane.
The amount of foam stabilizer added to the urethane resin is preferably in the range of 0.1 to 10 parts by mass, for example, per 100 parts by mass of the urethane resin.
Each of the resinization catalyst, trimerization catalyst, blowing agent, and foam stabilizer may be used alone or in combination of two or more.

The urethane resin composition may further contain an inorganic filler other than the solid flame retardant described above. Examples of inorganic fillers include, but are not limited to, silica, diatomaceous earth, alumina, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, basic magnesium carbonate, calcium carbonate, and magnesium carbonate. , zinc carbonate, barium carbonate, wollastonite, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, gypsum fiber, potassium salts such as calcium silicate, talc, clay, mica, montmorillonite, bentonite, activated clay, seviolite, imogolite. , sericite, glass fiber, glass beads, silica balloon, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon fiber, carbon balloon, charcoal powder, various metal powders, potassium titanate, magnesium sulfate, zirconate titanate Examples include lead, aluminum borate, molybdenum sulfide, silicon carbide, stainless steel fibers, various magnetic powders, slag fibers, fly ash, silica alumina fibers, alumina fibers, silica fibers, and zirconia fibers.
The inorganic fillers may be used alone or in combination of two or more.

Furthermore, the urethane resin composition may contain antioxidants such as phenolic, amine, and sulfur-based antioxidants, heat stabilizers, metal damage inhibitors, antistatic agents, stabilizers, etc., as necessary, within a range that does not impair the purpose of the present invention. It may contain additives such as agents, crosslinking agents, lubricants, softeners, pigments, tackifier resins, and tackifiers such as polybutene and petroleum resins.

Since the urethane resin composition reacts and cures, it is advisable to divide it into two liquids before molding the urethane foam. Specifically, it is preferable to divide the solution into a polyol liquid containing a polyol compound and an isocyanate liquid containing a polyisocyanate compound. At this time, components other than the polyol compound and the polyisocyanate compound may be appropriately blended into the polyol solution or isocyanate solution, but are preferably blended into the polyol solution. This is because polyol compounds have low reactivity and are unlikely to cause side reactions even when mixed with components other than the polyol compound and polyisocyanate compound.

The urethane resin composition can be made into urethane foam by injecting it into the cavity 12a of the rib 12, and hardening and foaming in the cavity 12a. The method of injecting the urethane resin composition into the cavity 12a of the rib 12 is not particularly limited, but the polyol liquid and the isocyanate liquid are mixed before being injected into the cavity 12a of the rib 12 to obtain a mixture. The mixture may be injected into the cavity 12a of the rib 12, or the polyol solution and the isocyanate solution may be separately injected into the cavity 12a of the rib 12 and mixed in the cavity 12a.
Specifically, although not particularly limited, an isocyanate liquid agent and a polyol liquid agent are separately stored in two containers, mixed with a caulking gun, etc., and the mixture is discharged from the caulking gun and inside the rib. It is best to inject it.
In a urethane resin composition, a reaction starts when the components are mixed, and the viscosity increases over time, hardening and foaming progress, and fluidity is lost to form polyurethane foam. The urethane resin composition is usually cured and foamed by being left at room temperature (for example, about 10 to 40°C), but if necessary, it may be heated and injected.

<Fire compartment structure>
The fire protection compartment structure according to this embodiment will be explained below.
As shown in FIG. 4, the fireproof compartment structure according to the present embodiment includes the flat deck 1 and a noncombustible material 20 filling the space between the ribs 30 on one surface 11D of the flat portion 11 of the flat deck 1. The flat deck 1 is arranged so that one surface 11D of the flat portion 11 and a partitioning material 31 such as gypsum board are butted against each other. Specifically, for example, the partitioning material 31 is arranged such that the upper end surface thereof is butted against the bottom surface of the rib 12. In this state, the flat deck 1 and the partitioning material 31 may be attached using screws or the like. Then, the space between the ribs 30, which is the gap between the flat deck 1 and the partition material 31, is filled with the noncombustible material 20, and a fireproof partition structure as shown in FIG. 4 is obtained. By filling the gaps 30 between the ribs with the noncombustible material 20, fire prevention performance can be ensured.
Furthermore, also on the outside of the rib 12, a non-combustible material (not shown) may be provided between the partitioning material 31 and the lower surface 11D of the flat deck 1, if necessary.
As the noncombustible material 20, known noncombustible materials that can fill gaps can be used, such as rock wool and glass wool.
Note that the noncombustible material 20 may be omitted, and instead, the shape of the upper end of the partitioning material 31 may be adjusted as appropriate to fill the gap between the ribs 12.

In the fire protection partition structure according to this embodiment, the flat deck 1 is laid across supporting materials such as beams of a building structure, and constitutes a floor structure, a roof structure, and the like. The flat deck 1 is used, for example, as a formwork material, and when used as a formwork material, concrete (not shown) is placed on the upper surface 11U.

As described above, in this embodiment, by filling the cavity 12a of the rib 12 with the filler 13, the cavity formed inside the rib 12 prevents the formation of a gap between the sections, resulting in a favorable condition. It is possible to form compartments having fireproofing properties, sound insulation properties, heat insulation properties, etc. Further, as described above, by making the filler 13 nonflammable, fire prevention properties become better. Furthermore, the fire prevention performance can be further improved by filling the gaps 30 between the ribs with the noncombustible material 20. Furthermore, in the flat deck 1 according to the present embodiment, the ratio of the density of the rib interface part 13b to the density of the a part 13a of the filler 13 provided inside the rib 12 is a predetermined value or more, so that the rib The shrinkage of the filler 13 inside the filler 12 can be suppressed, and fireproof performance can be maintained.
In addition, in this embodiment, by inserting and fitting the claw portion 14 of another flat deck 1 arranged adjacently into the unfilled portion 15 provided inside the rib 12 of the flat deck 1, It becomes possible to connect the flat decks 1 arranged adjacent to each other, and the workability becomes good.

(Other embodiments)
Although the embodiment in which the rib 12 is provided with the injection port 16 has been described above, the rib 12 may not be provided with the injection port 16. When the rib 12 is not provided with the injection port 16, it is preferable to fill the inside of the rib 12 with the filler 13 from other than the injection port. The filler material may be filled into the ribs 12 from above. Further, the injection port 16 of the rib 12 may be provided at a location other than the bottom surface portion.

The present invention will be explained in more detail below using Examples, but the present invention is not limited to these Examples.
In addition, the measurement method and evaluation method of each physical property in this invention are as follows.

[density]
The core part and the rib interface part of the urethane foam filled inside the ribs of the flat deck were cut out. The densities of the core region and the rib interface region were each measured in accordance with JIS K7222:2005. Then, from the measurement results, the ratio of the density of the rib interface region to the density of the core region (density of the rib interface region/density of the core region) was calculated. The results are shown in Table 1.
In addition, in measuring the density, the core part of the urethane foam was cut out from a part that was 5 mm or more from the inner surface of the rib. In addition, the rib interface portion of the urethane foam was cut out from a location within 5 mm from the inner surface of the rib.

[Shrinkage (fire protection)]
A fire resistance test was conducted on the flat deck that had been injected and filled using a refractory furnace and heated based on the ISO834 heating curve. If the smoke escapes to the non-heated surface within 60 minutes after heating, it will be evaluated as "C", if it is more than 60 minutes and within 120 minutes, it will be evaluated as "B", and if it is more than 120 minutes, it will be evaluated as "A". evaluated.

According to the formulation shown in Table 1, in order to obtain urethane foams related to Examples and Comparative Examples, two components were prepared: (1) a polyol-containing composition and (2) a polyisocyanate. The details of the components in Table 1 are as follows.

(1) Polyol-containing composition [polyol]
・P-phthalic acid polyester polyol (Maximol RLK-087, manufactured by Kawasaki Chemical Industries, Ltd., hydroxyl value = 200 mgKOH/g)
〔catalyst〕
・Trimerization catalyst, 2,2-dimethylpropanoic acid tetramethylammonium salt (DABCO TMR-7), manufactured by Air Products, mixture with ethylene glycol (2,2-dimethylpropanoic acid tetramethylammonium salt 45-55% by mass) , 45-55% by mass of ethylene glycol)
・Resinated amine catalyst, 1,2-dimethylimidazole (TOYOCAT-DM70), manufactured by Tosoh Corporation, mixture with ethylene glycol (1,2-dimethylimidazole 65-75% by mass, ethylene glycol 25-35% by mass) )
・Resinized metal catalyst, bismuth trioctate (Neostan U-600, manufactured by Nitto Kasei Co., Ltd., concentration 55-58% by mass)
[Foam stabilizer]
・Silicone foam stabilizer (SH-193, manufactured by Dow Corning Toray)
[Foaming agent]
・Hydrofluoroolefin (HFO, Soltis LBA, manufactured by Honeywell Japan)
・Water [liquid flame retardant]
・Tris (β-chloropropyl) phosphate (TMCPP, manufactured by Daihachi Kagaku Co., Ltd.)
[Solid flame retardant]
・Red phosphorus flame retardant (manufactured by Rin Kagaku Kogyo Co., Ltd., product name: Nova Excel 140, metal hydroxide coating, red phosphorus content of 94% by mass or more)
・Zinc borate (manufactured by Hayakawa Shoji Co., Ltd., product name: Firebrake ZB)
・Ethylene bis(pentabromophenyl) (manufactured by Albemarle, product name: SAYTEX 8010)

(2) Polyisocyanate/4,4'-diphenylmethane diisocyanate (4,4'-MDI) (PM200, manufactured by Wanka Kagaku Japan Co., Ltd.)

[Example 1]
A polyol-containing composition and a polyisocyanate having a formulation for forming a urethane foam shown in Table 1 were prepared, and each was stored in a closed container. Using a spraying device H-25 manufactured by Graco, a urethane resin composition prepared by mixing the polyol-containing composition and polyisocyanate discharged from each sealed container was poured into the injection port provided at the center of the rib bottom of the flat deck. 190 g (volume before foaming) was injected into the inside of the rib (volume 3162 ml). Note that during the injection, the rib temperature was heated to 70° C. using a band-shaped rubber heater. The urethane resin composition injected into the inside of the rib was reacted and foamed to form urethane foam as a filler filling the inside of the rib.

[Example 2]
In order to form a urethane foam, the same procedure as in Example 1 was carried out except that the formulation of the solid flame retardant was changed.

[Example 3]
In order to form urethane foam, the same procedure as in Example 1 was carried out except that no solid flame retardant was added.

[Example 4]
In order to form urethane foam, the same procedure as in Example 1 was carried out except that the catalyst composition was changed and the solid flame retardant was not blended.

[Example 5]
In order to form urethane foam, the same procedure as in Example 1 was carried out except that the rib temperature was changed to 110°C.

[Example 6]
In order to form a urethane foam, the same procedure as in Example 1 was carried out except that the injection amount of the urethane resin composition was changed to 175 g (volume before foaming).

[Example 7]
In order to form a urethane foam, the same procedure as in Example 1 was carried out except that the injection amount of the urethane resin composition was changed to 205 g (volume before foaming) and the rib temperature was changed to 110°C.

[Example 8]
In order to form a urethane foam, the same procedure as in Example 1 was carried out except that the injection amount of the urethane resin composition was changed to 175 g (volume before foaming) and the rib temperature was changed to 40°C.

[Example 9]
In order to form urethane foam, the solid flame retardant was not added, the injection amount of the urethane resin composition was changed to 205g (volume before foaming), and the rib temperature was changed to 40°C. was carried out in the same manner as in Example 1.

[Example 10]
In order to form a urethane foam, the same procedure as in Example 1 was carried out except that the injection amount of the urethane resin composition was changed to 140 g (volume before foaming) and the rib temperature was changed to 110°C.

[Comparative example 1]
In order to form a urethane foam, the same procedure as in Example 1 was carried out except that the injection amount of the urethane resin composition was changed to 190 g (volume before foaming) and the rib temperature was changed to 25°C.

[Comparative example 2]
In order to form a urethane foam, the same procedure as in Example 1 was carried out except that the injection amount of the urethane resin composition was changed to 140 g (volume before foaming).
Since the amount of urethane resin composition injected into the ribs was reduced, when the rib temperature was 70°C, the urethane resin composition did not reach the ends of the ribs, resulting in a situation where the urethane foam was not filled.

[Comparative example 3]
In order to form urethane foam, the process was carried out in the same manner as in Example 1, except that the rib temperature was changed to 120°C and the injection amount of the urethane resin composition was changed to 205 g (volume before foaming). .
By raising the rib temperature to 120° C. and increasing the amount of urethane resin composition injected into the ribs, the urethane resin composition leaked out of the injection port, making filling impossible.

As shown in Table 1, in each example, shrinkage of the urethane foam as a filler can be suppressed by setting the ratio of the density of the rib interface region to the density of the core region to a specific value or more. , it was possible to maintain fire resistance.

1 Flat deck 11 Flat part 11D Bottom surface (one side)
11U Upper surface 12 Rib 12a Cavity part 12b Connection part 13 Filler 13a Core part 13b Rib interface part 14 Claw part 15 Unfilled part 16 Inlet 17 Spacer 20 Noncombustible material 30 Between ribs 31 Partition material

Claims (9)

comprising a flat part, a rib protruding from one surface of the flat part, and a filler provided inside the rib,
A flat deck, wherein the ratio of the density of the rib interface portion of the filling to the density of the core portion of the filling is 1.01 or more and 1.20 or less. 2. The flat deck of claim 1, wherein the fill is a foam. A flat deck according to claim 1, wherein the filling is an organic foam. 4. The flat deck of claim 3, wherein the organic foam is urethane foam. The flat deck according to claim 4, wherein the density of the core portion of the urethane foam is 20 kg/m ³ or more and 75 kg/m ³ or less. The flat deck according to claim 4, wherein the density of the rib interface portion of the urethane foam is 23 kg/m ³ or more and 80 kg/m ³ or less. The filling conforms to ISO 5660-1 and has a total calorific value of 8 MJ/m ² or less for 20 minutes after the start of heating at a radiant heat intensity of 50 kW/m ² in a heat generation test using a cone calorimeter tester. A flat deck according to claim 1. The flat deck according to claim 1, wherein the rib has an injection port in a bottom portion for injecting the filler. A flat deck according to any one of claims 1 to 8,
and a noncombustible material filling between the ribs on one surface of the flat portion of the flat deck.