JP7050579B2 - Phenol resin foam laminated board and its manufacturing method - Google Patents

Description

The present invention relates to a phenolic resin foam laminated board and a method for producing the same.

Due to the recent increase in awareness of energy conservation and the mandatory next-generation energy conservation standards, high heat insulation and airtightness of houses are required. Under these circumstances, foamed plastic-based heat insulating materials are attracting attention, and among them, phenolic resin foam laminated boards with high heat insulating performance have flame retardancy and heat resistance, and are therefore preferably used as building materials and industrial materials. Has been done.

By the way, since such a foam laminated board is constructed along a wall or a floor, it is not preferable that warpage occurs in the thickness direction. However, warpage may occur in an environment where the product is stored at a high temperature for a certain period of time. In particular, in the foam laminated board in which the paper surface material is laminated on the surface, the difference in drying shrinkage between the upper and lower surface layers of the phenol resin foam laminated board is likely to occur at high temperature due to its high hygroscopicity, and it is easy to warp.

As a solution to the warp of the phenolic resin foam laminated board, for example, a method of suppressing the warp generated by heating from one surface is known (Patent Document 1). However, when the phenolic resin foam laminate was stored at a high temperature, this method was insufficient to suppress warpage.

Patent No. 6159468

The present invention provides a phenolic resin foam laminated board whose warpage is suppressed even when stored at a high temperature.

That is, the present invention provides the following [1] to [4].
[1] A plate-shaped phenol resin foam having a density of 20 kg / m ³ or more and 100 kg / m ³ or less, a closed cell ratio of 80% or more, and an average cell diameter of 50 μm or more and 300 μm or less, and the thickness of the phenol resin foam. A phenol formaldehyde foam laminated board provided with a first face material and a second face material provided on both sides facing each other in the direction.
The first face material and the second face material are papers, and there is a portion where the first face material, the second face material, and the phenol resin foam coexist, and there is a portion. A phenol resin foam laminated board in which the peel strength P1 between the phenol resin foam and the first face material and the peel strength P2 between the phenol resin foam and the second face material satisfy the following formulas.
0.70 ≤ P1 / P2 ≤ 1.43
[2] The phenolic resin foam laminated board according to [1] , wherein the first face material and the second face material have a basis weight of 15 to 200 g / m ² .
[3] The thermal conductivity of the phenolic resin foam in an environment of 10 ° C. is 0.0180 W / m · K or less, and the thermal conductivity in an environment of 23 ° C. is 0.0190 W / m · K or less. The phenolic resin foam laminate according to [1] or [2].
[4] A foam curing step of foaming and curing between a top material and a bottom material sandwiching a foaming phenol resin composition containing a phenol resin, a surfactant, a curing catalyst and a foaming agent is included.
In the foam curing step, the difference between the first time point t1 in which the discharged foamable phenol resin composition comes into contact with the lower surface material and the second time point t2 in contact with the upper surface material is 100 seconds or less. There is a third time point t3 in which the back side of the place where the lower surface material is in contact with the foamable phenol resin composition at the first time point is in contact with the first conveyor, and the upper surface material is said to be foamable at the second time point. Any of [1] to [3] , the difference between the back side of the place in contact with the phenolic resin composition and the fourth time point t4 in contact with the second conveyor facing the first conveyor is 450 seconds or less. A method for manufacturing one phenol resin foam laminated board.

According to the present invention, it is possible to provide a phenol resin foam laminated plate having high heat insulating performance and suppressing the amount of warpage in the thickness direction when stored at a high temperature, and a method for producing the same.

It is a block diagram which shows the schematic structure of a part of the manufacturing apparatus which performs the foam hardening process included in the manufacturing method of the phenol resin foam laminated board which concerns on one Embodiment of this invention. It is an enlarged view around the nozzle and the roller for demonstrating the time lapse from the contact with the lower surface material to the contact with the upper surface material of the foamable phenol resin composition discharged from the nozzle in FIG. 1. Between the first conveyor and the second conveyor in FIG. 1, the first conveyor and the first conveyor for explaining the time lapse from the contact of the laminated body with the first conveyor to the contact with the second conveyor. It is an enlarged view near the entrance of the conveyor of 2. It is sectional drawing along the thickness direction of the phenol resin foam laminated board which connected diagonal vertices with a thread for demonstrating the evaluation method in a warp evaluation test.

Hereinafter, embodiments of the phenolic resin foam laminated board of the present invention and a method for producing the same will be described.

(Phenol resin foam laminated board)
The phenol resin foam laminated board of the present embodiment is a plate-shaped phenol resin foam obtained by foaming and curing a foamable phenol resin composition containing a phenol resin, a surfactant, a curing catalyst, and a foaming agent. It is a laminated board provided with a body and a first face material and a second face material provided on both sides of the phenol resin foam facing each other. Unless otherwise specified, the phenol resin as one component of the effervescent phenol resin composition in the present specification is produced together with a pure phenol resin by the synthesis of phenols and aldehydes, and the moisture remaining even after dehydration. It is a phenolic resin raw material including.

(Phenol resin)
The phenol resin in the present embodiment is typically a condensation polymer of phenols and formaldehydes. The phenol resin can be obtained, for example, by using phenols and formaldehyde as raw materials and heating them with an alkaline catalyst in a temperature range of 40 ° C. or higher and 100 ° C. or lower to polymerize them.

Here, the phenols preferably used in the synthesis of the phenolic resin in the present embodiment are phenol itself and other phenols, and examples of other phenols include resorcinol, catechol, o-, and m-. And p-cresol, xylenols, ethylphenols, p-tert butylphenol and the like. Also, dinuclear phenols can be used.

Further, the aldehydes may be any compound that can be an aldehyde source, and it is preferable to use formaldehyde itself, other aldehydes or derivatives thereof as the aldehydes. Examples of other aldehydes include glyoxal, acetaldehyde, chloral, furfural, benzaldehyde and the like.

(Weight average molecular weight of phenolic resin)
The weight average molecular weight (Mw) obtained by gel permeation chromatography of the phenol resin obtained by polymerization is usually preferably 400 or more and 3000 or less, more preferably 500 or more and 2500 or less, and further preferably 700 or more and 2500 or less. It is particularly preferably 1000 or more and 2000 or less, and most preferably 1500 or more and 2000 or less.

(Molecular weight distribution of phenolic resin)
The molecular weight distribution (Mw / Mn), which is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) obtained by gel permeation chromatography of the phenol resin in the present embodiment, is 1.5 or more and 6.0 or less. It is preferably 2.0 or more and 5.5 or less, more preferably 2.2 or more and 5.0 or less, and particularly preferably 2.7 or more and 4.5 or less. Most preferably 3.0 or more and 4.0 or less.

(Phenol resin viscosity)
The viscosity of the phenol resin as one component of the effervescent phenol resin composition in the present embodiment is preferably 5000 mPa · s or more and 50,000 mPa · s or less at 40 ° C. The viscosity is more preferably 7,000 mPa · s or more and 40,000 mPa · s or less, further preferably 7,000 mPa · s or more and 30,000 mPa · s or less, and particularly preferably 7,000 mPa · s or more and 20,000 mPa · s or less.

(Surfactant)
As the surfactant, those generally used for producing a phenol resin foam can be used, and among them, a nonionic surfactant is effective. Surfactants are polyoxyalkylene (alkylene oxide) which is a copolymer of ethylene oxide and propylene oxide, a condensate of alkylene oxide and castor oil, and a condensate of alkylene oxide and nonylphenol and alkylphenol such as dodecylphenol. , The alkyl ether moiety contains at least one compound selected from polyoxyethylene alkyl ethers having 14 to 22 carbon atoms, fatty acid esters such as polyoxyethylene fatty acid esters, silicone compounds such as polydimethylsiloxane, and polyalcohols. Is preferable. These compounds may be used alone or in combination of two or more. The amount of the surfactant is not particularly limited, but is preferably 0.3 or more and 10 parts by mass or less with respect to 100 parts by mass of the phenol resin.

(Curing catalyst)
The curing catalyst may be any acidic curing catalyst capable of curing the phenol resin, but an anhydrous acid curing catalyst is preferable. As the anhydrous acid curing catalyst, anhydrous phosphoric acid and anhydrous aryl sulfonic acid are preferable. Examples of the aryl sulfonic acid anhydride include toluene sulfonic acid, xylene sulfonic acid, phenol sulfonic acid, substituted phenol sulfonic acid, xylenol sulfonic acid, substituted xylenol sulfonic acid, dodecylbenzene sulfonic acid, benzene sulfonic acid, naphthalene sulfonic acid and the like. These may be used alone or in combination of two or more. Further, resorcinol, cresol, saligenin (o-methylolphenol), p-methylolphenol and the like may be added as a curing aid. Further, these curing catalysts may be diluted with a solvent such as ethylene glycol or diethylene glycol. The amount of the curing catalyst is not particularly limited, but is preferably 3 or more and 30 parts by mass or less with respect to 100 parts by mass of the total amount of the phenol resin and the surfactant.

(Effervescent agent)
As the foaming agent in the phenol resin foam of the present embodiment, chlorinated hydrofluoroolefins or non-chlorinated hydrofluoroolefins, halogenated hydrocarbons, hydrocarbons and the like can be used.

Examples of the chlorinated or non-chlorinated hydrofluoroolefin include 1-chloro-3,3,3-trifluoropropene, 2-chloro-3,3,3-trifluoropropene, 1,3,3,3-tetra. Fluoro-1-propene, 2,3,3,3-tetrafluoro-1-propene, 1,1,1,4,4,4-hexafluoro-2-butene and the like can be used.

As the halogenated hydrocarbon, for example, as the chlorinated hydrocarbon, those having 2 to 5 carbon atoms such as dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, and isopentyl chloride are preferably used.

In addition, for example, as fluorinated hydrocarbons, difluoromethane, 1,1,1,2,2-pentafluoroethane, 1,1,1-trifluoroethane, 1,1,2,2-tetrafluoroethane, etc. 1,1,1,2-tetrafluoroethane, 1,1-difluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, 1,1,1,3,3-pentafluoropropane, 1,1,1,3,3-pentafluorobutane, 1,1,1,2,2,3,4,5,5-decafluoropentane and the like can be used. Among them, isopropyl chloride having a low ozone depletion potential and excellent environmental compatibility is particularly preferably used.

As the hydrocarbon, for example, cyclic or chain-like alkanes, alkenes, and alkynes having 3 to 7 carbon atoms can be used as the foaming agent. Specifically, normal butane, isobutane, cyclobutane, normal pentane, isopentane, cyclopentane, neopentane, normal hexane, isohexane, 2,2-dimethylbutane, 2,3-dimethylbutane, cyclohexane and the like are preferably used. Among them, compounds selected from pentanes such as normal pentane, isopentane, cyclopentane and neopentane, and butanes such as normal butane, isobutane and cyclobutane are preferable.

(Amount of foaming agent added to the foamable phenol resin composition)
The amount of the foaming agent added to the effervescent phenolic resin composition of the present embodiment is preferably 3.0 parts by mass or more and 25.0 parts by mass or less with respect to 100 parts by mass of the total amount of the phenol resin and the surfactant. More preferably 5.0 parts by mass or more, 20.0 parts by mass or less, further preferably 5.0 parts by mass or more and 15.0 parts by mass or less, particularly preferably 7.0 parts by mass or more and 13.0 parts by mass or less. Is.

(Effervescent nucleating agent)
In the present embodiment, it is preferable that the effervescent phenol resin composition contains a effervescent nucleating agent. As the effervescent nucleating agent, a gas effervescent nucleating agent such as nitrogen, helium, argon, air, or a low boiling point substance having a boiling point lower than that of the effervescent agent by 50 ° C. or higher can be mainly used. Also, aluminum hydroxide powder, aluminum oxide powder, calcium carbonate powder, talc, clay (kaolin), silica stone powder, silica sand, mica, calcium silicate powder, wallastnite, glass powder, glass beads, fly ash, silica fume. , Inorganic powders such as gypsum powder, hosand, slag powder, alumina cement, Portoland cement, and solid foam nucleating agents such as organic powders such as crushed powder of phenolic resin foam can also be added. These may be used alone or in combination of two or more without distinction between gas and solid. The timing of addition of the effervescent nucleating agent may be arbitrarily determined as long as it is supplied in the mixer in which the effervescent phenol resin composition is mixed.

The amount of the gas foam nucleating agent added to the foaming agent in the present embodiment is preferably 0.2% by mass or more and 1.0% by mass or less, preferably 0.3% by mass or more, with the amount of the foaming agent being 100% by mass. It is more preferably 0.5% by mass or less. The amount of the solid foam nucleating agent added to the foaming agent is preferably 3.0 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass in total of the phenol resin and the surfactant. It is more preferably 0 parts by mass or more and 8.0 parts by mass or less.

(Other additives)
The effervescent phenolic resin composition of the present embodiment may contain additives in addition to the components described. When urea is added as an additive, as is generally known, urea may be added directly to the reaction solution during the reaction of the phenol resin or at a timing near the end point, or it is converted into methylol with an alkaline catalyst in advance. The urea may be mixed with a phenol resin. As the additive other than urea, for example, phthalates generally used as a plasticizer, ethylene glycol and diethylene glycol which are glycols, and the like can be used. Further, an aliphatic hydrocarbon, a high boiling point alicyclic hydrocarbon, or a mixture thereof may be used as an additive. The content of the additive is preferably 0.5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the phenol resin. When these additives are 20 parts by mass or less, the viscosity of the phenol resin becomes optimum, and there is a tendency to prevent foam breakage during foaming and curing. When the amount of the additive is 0.5 parts by mass or more, the effect of the additive tends to appear.

(Face material)
The first face material and the second face material sandwiching the phenolic resin foam are sheet-like base materials, and are preferably flexible for the purpose of preventing the face material from breaking during production. .. Examples of the face material having flexibility include synthetic fiber non-woven fabric, synthetic fiber woven cloth, glass fiber paper, glass fiber woven cloth, glass fiber non-woven fabric, glass fiber mixed paper, papers, and metal film.

From the viewpoint of exudation of the effervescent phenol resin composition into the face material during foaming and the adhesiveness between the effervescent phenol resin composition and the face material, when a paper surface material is used as the face material, the amount of graining is preferable. It is 15 to 200 g / m ² , more preferably 15 to 150 g / m ² , still more preferably 15 to 100 g / m ² , particularly preferably 15 to 80 g / m ² , and most preferably 15 to 60 g / m ² .

If the type, thickness, and basis weight of the first face material and the second face material provided on both sides of the phenol resin foam facing each other are the same, the surface of the foamable phenol resin composition. It is preferable because it is difficult to make a difference in the degree of penetration into the material and it is easy to control the amount held in the face material.

[Production method]
The method for producing a phenolic resin foam laminated board of the present embodiment includes a discharge step, a coating step, and a foam curing step. In the discharge step, the effervescent phenol resin composition is discharged from the nozzle. In the coating step, the discharged effervescent phenolic resin composition is coated with a face material from above. Then, in the foam curing step, the foamable phenol resin composition sandwiched between the upper and lower surface materials is foamed and cured by heating the conveyor and the atmospheric temperature. Hereinafter, description will be given according to the drawings.

(Discharge process)
In the discharge step, the method of discharging the effervescent phenol resin composition onto the lower surface material is not particularly limited. For example, in the ejection process of the present embodiment, as shown in FIG. 1, the foamable phenol resin composition 12 is ejected from a plurality of nozzles 11 arranged in the TD direction of the production line on which the lower surface material 10 is running.

(Coating process)
In the coating step, for example, the foamable phenol resin composition 12 is coated with the upper surface material 13 by the following method. Downstream of the nozzle 11 in the traveling direction of the lower surface member 10, a roll 14 that is parallel to the lower surface member 10 and is rotatable about a direction perpendicular to the traveling direction is provided. In the manufacturing apparatus 15, the upper surface material 13 passes between the lower surface material 10 and the roll 14, and then travels in the same traveling direction as the lower surface material 10. The effervescent phenolic resin composition 12 discharged from the nozzle 11 first comes into contact with the running bottom surface material 10. The effervescent phenolic resin composition 12 in contact with the bottom surface material 10 advances to the position of the roll 14 together with the bottom surface material 10. The roll 14 coats the upper surface material 13 on the effervescent phenol resin composition 12. By coating the lower surface material 10 and the upper surface material 13 with the effervescent phenol resin composition 12, a laminate composed of the lower surface material 10, the upper surface material 13, and the effervescent phenol resin composition 12 is formed. One and the other of the lower surface material 10 and the upper surface material 13 correspond to the first face material and the second face material of the phenol resin foam laminated board, respectively.

As shown in FIG. 2, the portion 16 discharged at an arbitrary time point in the effervescent phenol resin composition 12 that is continuously discharged comes into contact with the lower surface material 10 at the first time point t1. The portion 16 is moved in the traveling direction by the lower surface material 10 and comes into contact with the upper surface material 13 near the position of the roll 14 in the traveling direction at the second time point t2 after the first time point t1.

In the present embodiment, the difference between the first time point t1 and the second time point t2 is 100 seconds or less. It is preferably 70 seconds or less, more preferably 40 seconds or less, still more preferably 20 seconds or less. If the time difference described above exceeds 100 seconds, the amount of the effervescent phenol resin composition 12 that permeates the lower surface material 10 side becomes too large. On the other hand, when the upper surface material 13 comes into contact, the curing reaction of the foamable phenol resin composition 12 proceeds, and the viscosity becomes too high, so that the foamable phenol resin composition 12 sufficiently penetrates into the upper surface material 13. No longer. As a result, the phenol resin foam coexisting in the face material is biased between the bottom surface material 10 and the top surface material 13. Therefore, it is not preferable that the above time difference exceeds 100 seconds.

(Foam hardening process)
In the coating step, the foamable phenol resin composition 12 sandwiched between the lower surface material 10 and the upper surface material 13 is subsequently sent to the foam curing step. In the foam curing step, for example, the foamable phenol resin composition 12 in the laminate is foamed and cured by the following method.

As shown in FIG. 1, in the foam curing step, the laminate is fed between the first conveyor 17 and the second conveyor 18. In the present embodiment, the first surface material 10 is in contact with the first conveyor 17 and the top surface material 13 is in contact with the second conveyor 18 in the laminated body conveyed from the position of the roll 14 in the traveling direction. The conveyor 17 and the second conveyor 18 are configured. The first conveyor 17 and the second conveyor 18 are parallel to each other and face each other at predetermined intervals. In the present embodiment, the first conveyor 17 and the second conveyor 18 have the same length, and the laminated body between them is conveyed in the traveling direction. Further, as will be described later, the first conveyor 17 and the second conveyor 18 are heated, and the foamable phenol resin composition 12 sandwiched between the lower surface material 10 and the upper surface material 13 is first from the roll 14. As it approaches the conveyor 17 and the second conveyor 18, it foams and increases in thickness due to an increase in the ambient temperature.

The thickness of the laminate is less than the distance between the first conveyor 17 and the second conveyor 18 immediately before being conveyed between the first conveyor 17 and the second conveyor 18. Therefore, in the present embodiment, as shown in FIG. 3, the arbitrary portion 20 of the laminated body 19 comes into contact with the first conveyor 17 at the lower surface material 10 at the third time point t3. At the fourth time point t4 after the third time point, the thickness of the portion 20 reaches the distance between the first conveyor 17 and the second conveyor 18.

In the present embodiment, the difference between the third time point t3 and the fourth time point t4 is 450 seconds or less, preferably 200 seconds or less, more preferably 100 seconds or less, still more preferably 50 seconds or less. When the above time difference exceeds 450 seconds, the effervescent phenol resin composition 12 on the face material side that has previously come into contact with the first conveyor 17 is heated and begins to cure, while the effervescent phenol resin composition in the upper surface material 13 begins to cure. Since the material continues to increase until it comes into contact with the second conveyor 18, the foamable phenol resin composition 12 in the face material is biased between the bottom surface material 10 and the top surface material 13.

The atmospheric temperature around the first conveyor 17 and the second conveyor 18 is 60 ° C. or higher and 95 ° C. or lower. If the ambient temperature is less than 60 ° C., it becomes difficult for the effervescent phenol resin composition 12 to obtain the required expansion ratio, and the desired phenol resin foam laminated board cannot be obtained. Further, it takes time for the other face material to come into contact with the second conveyor 18 due to the increase in thickness due to the foaming of the face material in contact with the first conveyor 17, and it takes time between the lower surface material 10 and the upper surface material 13. There tends to be a time lag until the face material and the respective conveyors 17 and 18 come into contact with each other. When the atmospheric temperature exceeds 95 ° C., the foaming property is strengthened, foam rupture is induced, the bubble diameter is coarsened, and the thermal conductivity tends to decrease.

In the present embodiment, the laminate 19 is then sent to a post-curing oven and a post-cure oven for heating. In the post-curing oven, the effervescent phenol resin composition 12 is cured in an atmosphere of 80 ° C. or higher and 110 ° C. or lower. The temperature inside the post-curing oven does not have to be uniform over the entire area, and a plurality of temperature zones may be provided.

It is preferable that the post-cure oven generates hot air at 90 ° C. or higher and 120 ° C. or lower to further promote the curing reaction of the phenol resin foam partially cured in the post-curing oven. The partially cured phenol resin foam laminated board may be stacked at regular intervals using a spacer or a tray. If the temperature in the post-cure oven is higher than 120 ° C., the pressure of the foaming agent inside the bubbles of the foam increases, which may induce foam rupture. Further, if the temperature of the post-cure oven is less than 70 ° C., it may take time to proceed the reaction of the phenol resin. Therefore, the temperature (hot air temperature) in the post-cure oven is more preferably 80 ° C. or higher and 110 ° C. or lower.

(density)
The density of the phenol resin foam in the present embodiment is 20 kg / m ³ or more and 100 kg / m ³ or less, preferably 20 kg / m ³ or more and 70 kg / m ³ or less, and more preferably 20 kg / m ³ or more and 40 kg / m 3. It is m ³ or less, more preferably 20 kg / m ³ or more and 35 kg / m ³ or less, and particularly preferably 20 kg / m ³ or more and 28 kg / m ³ or less.

If the density is lower than 20 kg / m ³ , the strength is low and the foam is easily damaged during transportation or construction. In addition, it cannot withstand the shrinkage stress due to heating, and the warp tends to be strong. In addition, the bubble film tends to be thin. When the bubble film is thin, the foaming agent in the foam is easily replaced with air, and the bubble film is easily broken during foaming, so that it is difficult to obtain a high closed cell structure, and the heat insulating performance tends to be deteriorated. On the other hand, when the density is higher than 100 kg / m ³ , the heat conduction of the solid derived from the solid component such as the phenol resin becomes large, so that the heat insulating performance tends to deteriorate.

(Closed cell ratio)
The closed cell ratio of the phenolic resin foam in the present embodiment is 80% or more, preferably 85% or more, more preferably 95% or more, still more preferably 97% or more. When the closed cell ratio is less than 80%, the foaming agent contained in the bubbles easily replaces air, so that the thermal conductivity after a long period of time becomes high, and the bubble film is easily broken, so that the compressive strength is low. Tend to become. In addition, due to the decrease in strength, it cannot withstand the shrinkage stress due to heating, and the warp tends to be strong.

(Average bubble diameter)
The average cell diameter of the phenolic resin foam in the present embodiment is 50 μm or more and 300 μm or less, preferably 50 μm or more and 250 μm or less, more preferably 60 μm or more and 200 μm or less, still more preferably 80 μm or more and 170 μm or less, and particularly preferably 100 μm or more and 170 μm or less. be. If the average bubble diameter is larger than 300 μm, the convection of gas in the bubbles and the heat insulation by the bubble film are reduced, so that the initial heat insulating performance tends to deteriorate. If the average bubble diameter is less than 50 μm, the individual bubble films become thin, so that the compressive strength tends to decrease.

(Thermal conductivity)
The thermal conductivity of the phenolic resin foam in the present embodiment is preferably 0.0180 W / m · K or less, more preferably 0.0175 W / m · K or less, and even more preferably 0.0175 W / m · K or less in an environment of 10 ° C. It is 0.0170 W / m · K or less. The lower limit is not particularly limited, but is usually about 0.014 W / m · K. The thermal conductivity of the phenolic resin foam laminate in the present embodiment measured in an environment of 23 ° C. is preferably 0.0190 W / m · K or less, more preferably 0.0185 W / m · K. It is less than or equal to, and more preferably 0.0180 W / m · K or less. The lower limit is not particularly limited, but is usually about 0.015 W / m · K. The method for measuring the thermal conductivity will be specifically described in Examples described later.

(Peeling strength ratio)
The peel strength ratio of the face material of the phenol resin foam laminated board in the present embodiment, that is, the peel strength P1 between the phenol resin foam and the first face material, and the peel strength P2 between the phenol resin foam and the second face material. The ratio (P1 / P2) to and is 0.70 or more and 1.43 or less, preferably 0.80 or more and 1.30 or less, and more preferably 0.90 or more and 1.10 or less.

In the phenolic resin composition in contact with the face material, when it permeates into the face material and becomes a foam, a portion where the face material and the foam coexist is generated. Since the foam has a stress of shrinking inside at the time of completion, the face material is pulled to the shrinking side, but the same amount of phenol resin foam coexisting inside the first face material and the second face material is present. If so, it is considered that the resistance to this contraction stress becomes the same and warpage is less likely to occur. The peel strength of the face material is an index of the amount of the phenol resin foam coexisting in the face material, and as P1 / P2 approaches 1, the phenol resin coexisting in the face material in the first face material and the second face material. It is considered that the amount of foam approaches the same amount and it becomes difficult to warp.

(Amount of warpage)
The phenolic resin foam laminated plate of the present embodiment has a warp amount of less than 10 mm, preferably 5 mm or less, and more preferably 3 mm or less according to a warp evaluation test described later. If the amount of warpage is 10 mm or more, when constructing a heat insulating material made of a phenol resin foam laminated board, there will be a problem that it will be difficult to construct the heat insulating material according to the dimensions and to screw it to a pillar or the like, resulting in airtightness. It is not preferable because the sealing material and the airtight tape for securing will be peeled off. Further, in a composite plate such as a metal sandwich panel, the phenol resin foam laminated plate and the metal may be peeled off, which is not preferable from such a viewpoint.

Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples. However, the present invention is not limited to the following examples.

The following items were measured and evaluated with respect to the composition, structure, and characteristics of the phenol resin and the phenol resin foam laminated board in Examples and Comparative Examples.

(1) Foam density The foam density of the phenol resin foam laminated board was measured according to JIS-K-7222. A 20 cm square laminated board cut out from the obtained phenol resin foam laminated board was used as a sample. Surface materials such as face materials and siding materials were removed from this sample, and the mass and apparent volume of the remaining foam sample were measured, and the foam density was determined from these values.

(2) Average Bubble Diameter The average bubble diameter of the phenol resin foam laminated plate was measured by the following method with reference to the method described in JIS-K-6402.

The center of the phenolic resin foam laminated plate in the thickness direction was cut in parallel with the front and back surfaces, and a photograph was taken in which the cut cross section was magnified 50 times. Four straight lines with a length of 9 cm (corresponding to 1,800 μm in the actual foam cross section) were drawn at arbitrary positions in the obtained photographs, and the average value of the number of bubbles crossed by each straight line was calculated. The average bubble diameter is a value calculated by dividing 1,800 μm by the average value of the number of bubbles crossed.

(3) Closed cell ratio The closed cell ratio of the phenol resin foam laminated plate was measured by the following method with reference to ASTM-D-2856-94 (1998) A method.

A cube piece of about 25 mm square was cut out from the central portion in the thickness direction of the foam. If a sample with a uniform thickness of 25 mm cannot be obtained due to the thin thickness of the foam, cut out the foam in a square shape of 25 mm square in the thickness direction, and cut out both surfaces of the cube plate surface by about 1 mm each. Slices were made to make specimens with uniform thickness. The length of each side was measured with a caliper, the apparent volume (V1: cm ³ ) was measured, and the mass of the specimen (W: 4 significant digits, g) was measured. Subsequently, using an air pycnometer (Tokyo Science Co., Ltd., trade name "MODEL1000"), the closed space volume (V2: cm ³ ) of the specimen was measured according to the method described in Method A of ASTM-D-2856. Further, the bubble diameter (t: cm) was measured according to the above-mentioned method for measuring the average bubble diameter. The surface area (A: cm ³ ) of the specimen was calculated from the length of each side already measured. By substituting the obtained t and A into the formula: VA = (A × t) /1.14, the opening volume (VA: cm ³ ) of the cut bubbles on the surface of the specimen was calculated. Further, assuming that the density of the solid phenol resin is 1.3 g / ml, the volume (VS: cm ³ ) of the solid portion constituting the bubble wall contained in the sample is calculated by the formula: VS = mass of the sample (W) /. Calculated according to 1.3.

The closed cell ratio was calculated by the following formula.
Closed cell ratio (%) = [(V2-VS) / (V1-VA-VS)] × 100
The closed cell ratio was measured 6 times for the foam obtained under the same production conditions, and the average value thereof was taken as the closed cell ratio of the foam obtained under the production conditions.

(4) Initial Thermal Conductivity According to JIS A 1412-: 1999, the initial thermal conductivity of the phenol formaldehyde foam laminated board was measured in the environment of 10 ° C. and 23 ° C. by the following method.

The phenolic resin foam laminated board was cut into 600 mm squares. The sample obtained by cutting was placed in an atmosphere of 23 ± 1 ° C. and a humidity of 50 ± 2%, and the change in mass with time was measured every 24 hours. The state of the specimen was adjusted until the mass change rate after 24 hours became 0.2% by mass or less. The condition-adjusted specimen was peeled off from the face material so as not to damage the foam, and then introduced into a thermal conductivity measuring device placed in the same environment.

The thermal conductivity was measured using one test piece and a measuring device using a heat flow meter method (Hideko Seiki Co., Ltd., trade name "HC-074 / 600"). The thermal conductivity in an environment of 10 ° C is 0 ° C for the low temperature plate and 20 ° C for the high temperature plate, and the thermal conductivity in the environment of 23 ° C is 13 ° C for the low temperature plate and 33 ° C for the high temperature plate. And each was measured.

(5) Viscosity of phenol resin or phenol resin raw material After stabilizing at 40 ° C for 3 minutes using a rotational viscometer (manufactured by Toki Sangyo Co., Ltd., R-100 type, rotor part is 3 ° x R-14). The value of the viscosity of was taken as the measured value.

(6) Weight average molecular weight Mw and ratio of weight average molecular weight Mw to number average molecular weight Mn Mw / Mn (molecular weight distribution)
Gel permeation chromatography (GPC) was measured under the following conditions. The weight average molecular weight Mw and the number average molecular weight Mn were determined from the obtained chromatogram and the calibration curve obtained by the relationship between the elution time and the molecular weight of the three standard substances shown later. Moreover, the molecular weight distribution Mw / Mn was calculated from these values.

Preprocessing:
Approximately 10 mg of phenolic resin was dissolved in 1 ml of N, N dimethylformamide (manufactured by Wako Pure Chemical Industries, Ltd., for high-speed liquid chromatograph), and filtered through a 0.2 μm membrane filter was used as a measurement solution.

Measurement condition:
Measuring device: Shodex System21 (manufactured by Showa Denko KK)
Column: Shodex asahipak GF-310HQ (7.5 mm ID x 30 cm)
Eluent: A solution in which lithium bromide was dissolved in N, N dimethylformamide (manufactured by Wako Pure Chemical Industries, Ltd., for high performance liquid chromatograph) at a concentration of 0.1% by mass was used as an eluent.
Flow rate: 0.6 ml / min Detector: RI detector Column temperature: 40 ° C
Standard substances: Standard polystyrene (Showa Denko Co., Ltd. Shodex standard SL-105), 2-hydroxybenzyl alcohol (99% product manufactured by Sigma-Aldrich Co., Ltd.), phenol (special grade manufactured by Kanto Chemical Co., Inc.)

(7) Face material peel strength Measurement was performed using AG-Xplus manufactured by Shimadzu Corporation. The obtained phenol resin foam laminated board was cut out in parallel in the thickness direction so as to have a width of 25 mm and a length of 150 mm, and a 90-degree peeling test of the face material was carried out at a speed of 200 mm / min with a peeling length of 85 mm. The maximum value was measured.

(8) Warpage Evaluation As shown in FIG. 4, the phenolic resin foam laminated plate 22 cut out to a size of 1000 mm × 1000 mm was allowed to stand at 90 ° C. for 48 hours, and then cured at room temperature for 2 days. A thread 23 is stretched between one diagonal apex of the cured phenol resin foam laminated board 22, and the maximum distance when a perpendicular line 24 is drawn from the thread 23 toward the plate surface of the phenol resin foam laminated board 22 is read. Recorded. Further, a thread 23 was stretched between the other diagonal vertices, and the measurement and recording were performed in the same manner. The same measurement was performed by turning it upside down, and the largest value among these four measured values was defined as warpage. If the thread did not become a straight line when the thread was stretched between the diagonal vertices, the warp was not calculated (when the phenol resin foam laminated plate 22 was measured in an upwardly convex state). The threads between the diagonals are not straight).

<Synthesis of phenolic resin>
Charge the reactor with 3500 kg of 52 mass% formaldehyde aqueous solution (52 mass% formalin) and 2510 kg of 99 mass% phenol (including water as impurities), stir with a propeller rotary stirrer, and adjust the temperature of the internal liquid of the reactor with a temperature controller. The temperature was adjusted to 40 ° C. Then, a 48 mass% sodium hydroxide aqueous solution was added until the pH reached 8.7, and then the temperature was raised to 85 ° C. to carry out the reaction. When the Ostwald viscosity of the reaction solution reaches 160 mm2 / sec (= 160 mm ² / s, measured value at 25 ° C.), the reaction solution is cooled and the urea content in the phenol resin becomes 4.6% by mass. Urea was added as described above. Then, the reaction solution was cooled to 30 ° C., and a 50% by mass aqueous solution of p-toluenesulfonic acid monohydrate was added until the pH reached 6.3. The obtained reaction solution was concentrated by a thin film evaporator to obtain a phenol resin having a viscosity at 40 ° C. of 9,800 mPa · s.

(Example 1)
<Manufacturing of phenolic resin foam laminated board>
3.0 parts by mass of a composition containing 50% each of a block copolymer of ethylene oxide-propylene oxide and polyoxyethylene dodecylphenyl ether as a surfactant with respect to 100 parts by mass of the synthesized phenol resin. Was mixed with the phenolic resin at the ratio of.

Then, with respect to 100 parts by mass of the phenol resin, 6.3 parts by mass of a mixture of 40% by mass of isopropyl chloride and 60% by mass of 1-chloro-3,3,3-trifluoropropene as a foaming agent, and nitrogen as a foaming nucleating agent. A composition consisting of a mixture of 0.40% by mass with respect to the foaming agent and 80% by mass of xylene sulfonic acid and 20% by mass of diethylene glycol as an acidic curing agent was added to 10 parts by mass of the above-mentioned phenol resin and surfactant. It was added to the mixture and supplied to a variable rotation speed mixing head whose temperature was adjusted to 30 ° C. The final mixture, the effervescent phenolic resin composition, was distributed by tournament piping and discharged onto the moving facing material. The time difference until the discharged effervescent phenolic resin composition is coated on the upper and lower surface materials is set to 20 seconds, and then the time difference until the upper and lower surface materials and each contact the conveyor is set to 50 seconds. It was sent to a slud type double conveyor. At this time, the distance between the first conveyor and the second conveyor was 50 mm, the conveyor temperature and the atmospheric temperature were 80 ° C., and foaming and curing were performed with a residence time of 15 minutes. Then, the phenol resin composition was post-cured by heating in an oven at 110 ° C. for 2 hours to obtain a plate-shaped phenol resin foam laminated plate. As the face material, a paper surface material and a basis weight of 30 g / m ² were used. The above-mentioned measurement and evaluation results using the phenolic resin foam laminated board of Example 1 are shown in Table 1.

(Example 2)
A phenol resin foam laminated plate was obtained in the same manner as in Example 1 except that the time difference until the discharged foamable phenol resin composition was coated on the upper and lower surface materials was 90 seconds. The above-mentioned measurement and evaluation results using the phenolic resin foam laminated board of Example 2 are shown in Table 1.

(Example 3)
Phenol resin foam laminated board in the same manner as in Example 1 except that the distance between the first conveyor and the second conveyor is 95 mm and the time difference until the upper and lower surface materials come into contact with the conveyor is 440 seconds. Got The above-mentioned measurement and evaluation results using the phenolic resin foam laminated board of Example 3 are shown in Table 1.

(Comparative Example 1)
A phenol resin foam laminated plate was obtained in the same manner as in Example 1 except that the time difference until the discharged foamable phenol resin composition was coated on the upper and lower surface materials was 110 seconds. The above-mentioned measurement and evaluation results using the phenol resin foam laminated board of Comparative Example 1 are shown in Table 1.

(Comparative Example 2)
Phenol resin foam laminated board in the same manner as in Example 1 except that the distance between the first conveyor and the second conveyor is 100 mm and the time difference until the upper and lower surface materials come into contact with the conveyor is 470 seconds. Got Table 1 shows the above-mentioned measurement and evaluation results using the phenolic resin foam laminated plate of Comparative Example 2.

10 Bottom material 11 Nozzle 12 Effervescent phenol resin composition 13 Top material 14 Roll 15 Manufacturing equipment 16 Part of the effervescent phenol resin composition that is continuously discharged at any time point 17 First conveyor 18th Conveyor of 2 19 Laminated body 20 Arbitrary part of laminated body 22 Phenol resin foam laminated board 23 Thread 24 Vertical wire

Claims (4)

A plate-shaped phenolic resin foam having a density of 20 kg / m ³ or more and 100 kg / m ³ or less, a closed cell ratio of 80% or more, and an average cell diameter of 50 μm or more and 300 μm or less, and the phenol resin foam in the thickness direction of each other. A phenol formaldehyde foam laminated board provided with a first face material and a second face material provided on both facing surfaces, respectively.
The first face material and the second face material are papers, and there is a portion where the first face material, the second face material, and the phenol resin foam coexist, and there is a portion. A phenol resin foam laminated board in which the peel strength P1 between the phenol resin foam and the first face material and the peel strength P2 between the phenol resin foam and the second face material satisfy the following formulas.
0.70 ≤ P1 / P2 ≤ 1.43 The basis weight of the first face material and the second face material is 15 to 200 g / m. ² The phenolic resin foam laminated board according to claim 1. The claim that the phenol resin foam has a thermal conductivity of 0.0180 W / m · K or less in an environment of 10 ° C. and a thermal conductivity of 0.0190 W / m · K or less in an environment of 23 ° C. The phenolic resin foam laminated board according to 1 or 2. It comprises a foam curing step of foaming and curing between a top and bottom material sandwiching a foaming phenolic resin composition containing a phenolic resin, a surfactant, a curing catalyst and a foaming agent.
In the foam curing step, the difference between the first time point t1 in which the discharged foamable phenol resin composition comes into contact with the lower surface material and the second time point t2 in contact with the upper surface material is 100 seconds or less. There is a third time point t3 in which the back side of the place where the lower surface material is in contact with the foamable phenol resin composition at the first time point is in contact with the first conveyor, and the upper surface material is said to be foamable at the second time point. Any one of claims 1 to 3 , wherein the difference between the back side of the place in contact with the phenolic resin composition and the fourth time point t4 in contact with the second conveyor facing the first conveyor is 450 seconds or less. The method for producing a phenolic resin foam laminated board according to the above item .

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