JP2015085272A - Floating lid and construction method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a floating lid which is excellent in strength and a method of constructing the floating lid which enables easy and short-period construction thereof and suppressed in turbidity of a liquid due to a polyurethane foaming raw liquid before hardening, even when the liquid surface (construction surface) of the floating lid is extensive and has a complex shape.SOLUTION: A floating lid consists of a substrate layer including floating pieces and polyurethane foam-made laminates arranged in parallel in the direction nearly perpendicular to the liquid surface. Alternatively, the floating lid consists of the substrate layer, the hard polyurethane foam-made first laminates arranged in parallel in the direction nearly perpendicular to the liquid surface and second hard polyurethane foam-made laminates arranged in double rows in the direction nearly horizontal to the liquid surface.

Description

  The present invention relates to a floating lid made of a rigid polyurethane foam having high strength and a method in which turbidity of a liquid surface hardly occurs when the floating lid is constructed.

  As a technology to protect the liquid surface, cover for the purpose of blocking flammable liquids, preventing volatilization of liquids, preventing the release of gaseous components such as odors, maintaining the aesthetic appearance, etc. Covers for the purpose of etc. are known.

However, with the conventional cover for the purpose as described above, for example, as described in Patent Documents 1 and 2, etc., people and animals get on or put equipment in an emergency or disaster. Or, when heavy objects such as debris fall, cracks may occur or break.
On the other hand, in order to obtain high strength in these conventional covers, simply adding a high-density formulation increases the number of parts that sink in the liquid due to its own weight, and as a result, it tends to swell. It is not preferable.

Recently, in order to protect the liquid level of large reservoirs and pools, in addition to durability for long-term outdoor use, improvement in workability is strongly demanded from the field.
As described in Patent Documents 1 and 2 described above, the method of pouring the polyurethane foam stock solution onto the surface of the liquid or the method of spraying the liquid toward the surface of the liquid has a vast liquid surface or a liquid having a complicated shape. It was never easy to form a floating lid having a thickness of 20 cm or more on the surface, and it took time and effort.

In order to solve the above-mentioned problems, the present inventors made a rigid polyurethane foam excellent in strength that is hard to break and does not submerge even if a person or an animal gets on or falls. Along with the floating lid, a method has been proposed in which the floating lid can be constructed easily and in a short period of time regardless of whether the liquid level (construction surface) is vast or complex.
When constructing the floating lid of Patent Document 3, it is confirmed that when the polyurethane foam stock solution comes into contact with the liquid surface, the liquid is contaminated or turbid, and in some cases, polyurethane foam particles accumulate on the bottom. . If turbidity and accumulated particles are left untreated, water quality such as sludge deteriorates, and improvement is required.

JP-A 63-317516 Japanese Patent Laid-Open No. 2-253841 Japanese Patent Application No. 2013-222102

  The present invention has a floating lid excellent in strength, and can be used for liquids caused by a polyurethane foam undiluted solution easily and in a short period of time even when the liquid surface (construction surface) is vast or complicated. It is an object of the present invention to provide a method capable of constructing the above-described floating lid that is less likely to cause turbidity.

As a result of various studies to solve the above-mentioned problems, the present inventors firstly sprayed a polyurethane foam stock solution, and at the same time, strongly adhered to an object without an adhesive, and instantly Focusing on foaming and curing, the size and shape of the floating lid was found to be adjustable by spraying repeatedly (stacking about 2 to 4 cm thick board pieces).
Next, if you start stacking the board pieces after forming a base layer on the liquid surface, you can not only prevent the liquid that is the object of construction from becoming cloudy, but also quickly respond to prevention of odor diffusion, liquid insulation, etc. You can also find what you can do,
Furthermore, if only such an underlayer and a laminate in the lateral direction (perpendicular to the liquid surface) are insufficient in terms of stress against the load from the top and durability, the longitudinal direction (relative to the liquid surface) In other words, it was found that buoyancy and strength can be further improved by combining with laminates stacked in the horizontal direction.

The present invention can be made based on the above findings,
[1] A floating lid that is constructed on site, and includes a base layer including a floating piece and a laminate made of a rigid polyurethane foam that is arranged in a direction substantially perpendicular to the liquid surface,
[2] Floating lids constructed on site,
An underlayer including a floating piece;
A first laminate made of rigid polyurethane foam juxtaposed in a direction substantially perpendicular to the liquid surface;
A floating lid comprising a second laminated body made of rigid polyurethane foam, which is substantially horizontally aligned with the liquid surface, on the first laminated body,
[3] A method of constructing the floating lid according to [1] by a spray method,
Form a base layer by covering the liquid surface with floating pieces,
Next, the polyurethane foam undiluted solution is sprayed toward the end base material side where the spray gun is erected on the liquid surface to form a laminate made of rigid polyurethane foam juxtaposed in a direction substantially perpendicular to the liquid surface. The floating lid construction method,
[4] A method of constructing the floating lid according to [2] by a spray method,
Form a base layer by covering the liquid surface with floating pieces,
Next, the polyurethane foam stock solution is sprayed toward the end base material side where the spray gun is erected on the liquid surface to form a first laminate made of rigid polyurethane foam parallel to the liquid surface in a substantially vertical direction,
Furthermore, the polyurethane foam undiluted solution is sprayed with the spray gun directed from the upper side to the lower side of the first laminated body, and the second laminated body made of rigid polyurethane foam that is superposed in a substantially horizontal direction with respect to the liquid surface is the first laminated body. A method of constructing a floating lid, characterized in that it is formed on the top,
[5] The floating piece is a foamed styrene bead or a foamed urethane piece. The polyurethane foam stock solution is sprayed with the spray gun directed obliquely upward from the liquid surface, and the foamed styrene beads covering the liquid surface are fixed to each other, and the underlayer The method for constructing a floating lid according to the above [3] or [4], characterized in that
Is the gist.

The floating lid made of the rigid polyurethane foam of the present invention has sufficient buoyancy and high strength, so that when a person or animal gets on it, puts equipment, or a heavy object such as debris falls, it will crack. And cracks are less likely to occur and do not submerge.
In addition, the closed cell structure of rigid polyurethane foam has a very low water absorption rate and is difficult to swell, and there is no significant change in basic physical properties such as strength over a long period of time. Absent. It can withstand long-term outdoor use (1 to several years).
Even if cracks occur on the foam surface, the buoyancy of the polyurethane foam itself is large and the total thickness is 20 cm or more, so that the liquid level is hardly or not exposed.

According to the construction method by the spray method of the present invention, even if the construction area is large or the construction liquid surface is complicated, a thick floating lid with excellent strength can be formed easily and in a short period of time. can do. The installer can get on the floating lid that he has constructed himself, and if the hose length of the spray gun connected to the urethane foam foaming machine is increased, the construction can be extended and repaired very easily.
Moreover, since there is an underlayer between the floating lid and the liquid surface, the unreacted polyurethane foam stock solution immediately after spraying does not touch the liquid surface, and the liquid turbidity and contamination can be reliably prevented. .
Furthermore, since the formation of the foundation layer is extremely easy, it is necessary to urgently prevent the inflow of rainwater and sewage in the event of guerrilla rain, etc., or to prevent the diffusion of dangerous odors before construction of the floating lid. In addition, this foundation layer can be used immediately (first aid).

It is explanatory drawing of the board piece parallel to a substantially perpendicular direction with respect to a liquid level. It is explanatory drawing of the board piece which overlaps with a substantially horizontal direction with respect to a liquid level. (A)-(C) are the schematic diagrams explaining an example of the construction method of the floating cover which concerns on 1st invention. It is a cross-sectional schematic diagram of the floating lid which concerns on 1st Embodiment corresponding to 1st invention. (A), (B) is a schematic diagram explaining an example of the construction method of the floating cover which concerns on 2nd invention. It is a cross-sectional schematic diagram of the floating lid which concerns on 2nd Embodiment corresponding to 2nd invention. It is a schematic diagram explaining the other example of the construction process of the floating cover which concerns on 2nd invention.

The floating lid according to the first aspect of the present invention is constructed on-site, and a base layer including a floating piece and a board piece made of rigid polyurethane foam having a thickness (t) of about 2 to 4 cm with respect to the liquid level. It consists of a laminated body arranged in parallel in a substantially vertical direction.
FIG. 1 is an explanatory diagram of the board pieces 3 arranged in parallel in a direction substantially perpendicular to the liquid level. In FIG. 1, the symbol t represents the thickness of the board piece 3, the symbol h represents the vertical width (height) of the board piece 3, and the symbol w represents the horizontal width of the board piece 3.
If the thickness t of the board piece 3 is too thin, the strength tends to be insufficient, and the number of sheets to be juxtaposed to cover the base layer increases, which complicates the construction. On the other hand, if the thickness t is too large, the reaction time for the curing of each board piece becomes long, and the construction time tends to be prolonged.

The size and shape of the board piece 3 are not particularly limited and can be appropriately determined depending on the construction area and the shape thereof, but it is easy to spray by a spray pattern discharged by a general spray gun, and the cooling time of reaction heat. In consideration of the workability and the like, a flat, substantially rectangular parallelepiped body having a spraying vertical width h of about 20 to 50 cm and a spraying lateral width w of about 30 to 90 cm is preferable.
The number of board pieces 3 to be juxtaposed can be determined by the thickness t of the board pieces, the construction area and the shape thereof.
In the floating lid according to the first aspect of the present invention, the sum of the spraying vertical width h and the thickness of the underlayer described later is the thickness of the floating lid to be obtained.

In the present invention, such a lateral laminate is formed on an underlayer including a floating piece.
The floating piece is not particularly limited as long as it floats on the liquid surface and does not cause turbidity of the liquid, and can be coated so that the liquid surface is not exposed. Styrene beads, foamed urethane boards, foamed urethane pieces (debris), various synthetic resin sheets (films), plywood, etc. can be used, and fallen leaves and floating substances (trash) that originally floated in ponds and pools can also be used. .
Above all, in consideration of on-site workability, compatibility with various liquid surface shapes, hygiene, ease of removal (disposal), etc., foamed styrene beads or foamed urethane pieces with a diameter of about 1 to 30 mm are suitable. It is. If two or more types of foamed styrene beads or foamed urethane pieces having different particle diameters are used, it becomes easy to spread the liquid surface without a gap so that the water surface is not exposed. For example, a small bead having a diameter of 1 to 5 mm and a large bead having a diameter of about 5 to 30 mm can be used.
Moreover, if it is a floating piece with releasability with respect to a rigid polyurethane foam, it will be easy to separate after construction or use of the floating lid.

When the base layer contains multiple floats, if the floats covering the liquid surface are fixed together, a laminate can be formed while preventing liquid turbidity more reliably, and the construction of the floating lid is abrupt. It also serves as an emergency lid when necessary, and it is preferable because a certain amount of time can be taken for the construction of the laminate.
Examples of materials that fix the floating pieces to each other (hereinafter also referred to as “adhesive material”) include an adhesive, an adhesive tape, a tucker, and a polyurethane foam stock solution. Among these, a polyurethane foam stock solution that can be a raw material for a laminate made of rigid polyurethane foam is preferable. This polyurethane foaming stock solution may be different from the polyurethane foaming stock solution forming the laminate, but it is more preferable to use the same composition because it is not necessary to replace the polyurethane foaming stock solution during the construction.
Regarding the thickness of the base layer including such a floating piece, although it depends on the material of the floating piece and the adhesive material, it is necessary to have a thickness that does not break when forming a laminated body by spraying, so it should be 1 cm or more. It is preferably about 3 to 6 cm.
Moreover, the size (construction area) of the base layer can be made substantially the same as the construction area of the laminate formed thereon.

The floating lid according to the second invention can further improve the strength and durability of the floating lid according to the first invention.
That is, in the floating lid according to the second invention, the floating lid according to the first invention (hereinafter referred to as the “horizontal laminate” in the floating lid according to the first invention, The second stacked body is formed on the “first stacked body”.
The second stacked body covers the entire top surface of the first stacked body (that is, the surface not facing the liquid surface), but may cover a part of the first stacked body depending on the application. .

The second laminated body is formed by stacking board pieces made of rigid polyurethane foam having a thickness (t) of about 2 to 4 cm on the first laminated body in a substantially horizontal direction with respect to the liquid surface, and overlapping them.
FIG. 2 is an explanatory diagram of the board pieces 4 arranged in parallel in a substantially horizontal direction with respect to the liquid level. In FIG. 2, the symbol t represents the thickness of the board piece 4, the symbol h represents the vertical width of the board piece 4, and the symbol w represents the horizontal width of the board piece 4.
If the thickness t of the board piece 4 is too thin, the number of sheets to be stacked in order to obtain a desired thickness and strength increases, and the construction becomes complicated. On the other hand, if the thickness t is too large, the construction time is likely to be prolonged as with the board piece 3 forming the first laminate.

The size and shape of the board piece 4 constituting the second laminated body can be appropriately determined depending on the area covering the first laminated body and the shape thereof, but in consideration of the ease of spraying and workability, the spraying vertical width A flat, substantially rectangular parallelepiped having h of about 10 to 50 cm and a spraying lateral width w of about 30 to 90 cm is preferable.
The number of board pieces 4 to be overlapped may be determined by the thickness t of the board pieces and the application for protecting the liquid surface, that is, the thickness and strength required for the floating lid.
The thickness of the floating lid according to the second invention (that is, the total thickness of the floating lid composed of the base layer, the first laminate, and the second laminate) is not particularly limited, but is preferably about 30 to 60 cm.

  As described above, in the second invention, the second laminate in which the board pieces 4 are overlapped in the substantially horizontal direction with respect to the liquid surface in the first laminate in which the board pieces 3 are arranged in parallel in the substantially vertical direction with respect to the liquid surface. By combining the bodies, the strength and buoyancy of the floating lid can be further increased, and it is possible to reliably prevent breakage and submersion when a person or animal rides or an object falls.

As the rigid polyurethane foam constituting the first laminate and the second laminate, those obtained by reacting polyol and polyisocyanate in the presence of a foaming agent, a catalyst and a foam stabilizer are used.
Further, in the polyurethane foaming stock solution, various additives such as a colorant, a flame retardant, and a hydrolysis inhibitor, which are used in the production of a normal rigid polyurethane foam, can be blended as necessary. In addition, an antioxidant other than phosphorus and a light stabilizer other than hindered amine may be added as long as the effect of preventing yellowing (discoloration) during outdoor use is not hindered.
In addition, since the floating lid of the present invention is constructed on site, it is preferable not to include a combustible compound, and as the foaming agent, water, hydrofluorocarbon, hydrofluoroolefin, carbon dioxide and the like are preferable. is there.

Such a rigid polyurethane foam preferably has a density measured according to JIS K7222 of 30 to 60 kg / m ³ , more preferably 40 to 60 kg / m ³ . Moreover, it is preferable that the closed cell rate measured based on ASTM D2856 is 80 to 100%, and the compressive strength measured based on JIS K7220 is 15 to 60 N / cm ² .
If the density is less than 30 kg / m ³ , the strength of the resulting floating lid may not be sufficiently obtained. Moreover, when it exceeds 60 kg / m < ³ >, the part which sinks in a liquid with dead weight will increase, and submergence and swelling will occur easily.
If the closed cell rate is less than 80%, the water absorption rate increases, and again, submergence and swelling easily occur.
If the compressive strength is less than 15 N / cm ² , cracks and cracks may occur when a person or animal rides on the formed floating lid or a heavy object falls, exceeding 60 N / cm ^2. However, the effect of preventing these cracks and cracks is saturated and the cost is increased.

The rigid polyurethane foam preferably has a dimensional change rate of 10% or less, more preferably 5% or less, still more preferably 1% or less, measured in accordance with ASTM D2126. The tensile elongation measured according to JIS A9511 is more preferably 10 to 20%.
When the dimensional change rate exceeds 10%, long-term use is difficult depending on the temperature and humidity conditions of the place of use.
If the tensile elongation is less than 10%, cracks and cracks are likely to occur at the time of deflection, and even if it exceeds 20%, the technical significance is saturated.

  In the second invention, the rigid polyurethane foam forming the first laminate and the rigid polyurethane foam forming the second laminate may be the same or different. It is preferable to use the same one because it is not necessary to replace the polyurethane foam stock solution during the construction.

The floating lids of the first and second inventions are, for example, a part of or the entire liquid surface such as water, seawater, polluted water (liquid waste), flammable liquid, fertilizer, etc., both indoors and outdoors. The period can be covered.
Moreover, when removing a part or all of a floating lid, it can also cut easily with a saw, an electric saw, etc.

  The floating lid of the present invention having the above configuration can be obtained by the following construction method of the present invention.

FIGS. 3A to 3C are schematic views for explaining an example of a floating lid construction method according to the first invention. FIG. 4 shows the first embodiment corresponding to the first invention. The cross-sectional schematic diagram of the floating cover which concerns is shown.
First, as illustrated in FIG. 3A, the floating piece 6 as described above is spread over a desired portion of the liquid surface S (hereinafter also referred to as “construction surface”), so that the entire construction surface is obtained. A base layer 7 is formed by covering. Although FIG. 3 shows a case where the foundation layer 7 includes a plurality of floating pieces 6, the foundation layer may include only one floating piece having a size that can substantially cover the entire construction surface.

Alternatively, as illustrated in FIG. 3B, the floating pieces 6 covering the construction surface can be fixed with the adhesive material 8 as described above to form a base layer.
FIG. 3B shows an example in which a polyurethane foam stock solution adjusted to increase the reaction rate is used as the adhesive material 8, and the foam stock solution is discharged at a low discharge pressure (the pressure applied to the floating piece 6 is low). The lower layer 7 ′ is formed by spraying on the floating piece 6.
When the foaming stock solution 8 is sprayed in a state where the discharge pressure is high (the pressure applied to the floating piece 6 is high), the floating piece 6 is temporarily sunk or displaced from a desired construction position, thereby exposing the liquid surface S. There is a possibility that a portion (that is, a portion where the base layer 7 ′ is not formed) is generated. Moreover, when the reaction rate is too slow, curing at the time of reaching the floating piece 6 is insufficient, which causes turbidity of the liquid level and accumulation at the bottom.

In addition, the installer does not spray the spray gun G containing the stock solution 8 directly toward the floating piece 6, but gently from the liquid surface S toward the diagonally upward as shown in FIG. By spraying, it is preferable that the pressure of the mist-like (fine particle-like) stock solution 8 discharged from the spray gun G is lowered to the floating piece 6 after the pressure is weakened to the extent that it falls by its own weight. The reaction of the fine particle stock solution 8 drifts in the air until it contacts the floating piece 6 and the surface of the particles begins to harden slightly, so that these particles do not mix with the liquid to be constructed. This is because the floating piece 6 can be fixed.
In this way, if the floating pieces 6 covering the construction surface are fixed together, an unreacted polyurethane foam stock solution immediately after spraying is formed on the liquid surface when the laminate is formed on the base layer 7 ′. Touching S can be prevented, and the occurrence of liquid turbidity can be reliably suppressed.

Next, as illustrated in FIG. 3C, a lateral laminate 10 is formed on the base layer 7 ′ (hereinafter, a plurality of floating pieces are fixed as the base layer in the figure). 7 'is illustrated, but of course, the underlayer 7 that does not stick the floating pieces to each other can be used). At this time, when the formation of the laminate 10 is started after one end of the base layer 7 ′ is brought into contact with the end base material M, it is preferable in that the liquid turbidity can be more reliably suppressed.
The end base M may be any material that is erected on the liquid surface S and made of a material to which the polyurethane foam stock solution adheres. For example, the end base is a portion where no liquid is present on the inner side surface of the pool or pond. It may be used as a material, or may be a foamed board, plywood, urethane board or the like fixed to the wall surface as an end base material, or a cement board or the like standing on the liquid surface S.
As shown in FIG. 3 (C), the polyurethane foam stock solution is sprayed with the spray gun G directed toward the end substrate M, so that the rigid polyurethane foam as described above is substantially perpendicular to the liquid surface S. The board pieces 3 made of the above are arranged in parallel, and a lateral laminate 10 is formed on the base layer 7 '.

The practitioner applies the spray gun G so that the lower part of the spray pattern is in contact with the surface of the base layer 7 ′ and the thickness (t) and size (h × w) of each board piece 3 are substantially uniform. It is preferable to stack the board pieces 3 in parallel while adjusting the speed of the arm movement in the horizontal (left and right) direction.
Moreover, since the board piece 3 immediately after spraying requires about 10 seconds or more to complete the foam hardening, an interval of about 10 to 20 seconds may be provided until the next board piece 3 is laminated.
And after forming the laminated body 10 of a certain magnitude | size, it can also be set as one cycle until it heat-dissipates for several tens of minutes-several hours, and can also transfer to the next cycle. The reason for providing the heat dissipation time is to prevent the hard polyurethane foam after being cooled from shrinking and shrinking to change its dimensions, or to prevent scorch from occurring due to an increase in internal temperature.

By repeating the parallel arrangement of the board pieces 3 until the entire base layer 7 'is covered, the base layer 7' and the lateral laminate 10 are formed as shown in the schematic cross-sectional view of FIG. The floating lid 100 according to the first embodiment is constructed. Hereinafter, the dotted line in the figure represents the joint between the board piece 3 and the board piece 3. A skin layer 3 'having a thickness of about 1 to 5 mm is usually present at this joint (that is, between each layer of the laminate 10).
In addition, even if the joint part of the laminated body 10 or the base layer 7 ′ and the end base material M is peeled off during the construction or after the construction, it can be easily repaired by immediately spraying the polyurethane foam stock solution, It will not be submerged by the buoyancy of the floating lid 100.

FIGS. 5A and 5B are schematic views for explaining an example of a floating lid construction method according to the second invention. FIG. 6 shows a second embodiment corresponding to the second invention. The cross-sectional schematic diagram of the floating cover which concerns is shown.
In the floating lid construction method according to the second invention, the laminated body 10 formed on the base layer 7 ′ in the floating lid 100 according to the first embodiment is referred to as a “first laminated body”, and the first laminated body 10. A second stacked body 20 is formed thereon.
First, as illustrated in FIG. 5A, the polyurethane foam stock solution is sprayed from above the first laminated body 10 downward from the first laminated body 10 to spray the polyurethane foam stock solution in a substantially horizontal direction with respect to the liquid surface S. The board pieces 4 made of such hard polyurethane foam are stacked in a row, and the vertical laminate 20 is formed on the first laminate 10.

The installer adjusts the speed of the arm movement in the horizontal (left and right) direction of the spray gun G so that the thickness (t) and size (h × w) of each board piece 4 are substantially uniform. It is preferable that the pieces 4 are stacked and overlapped. In FIG. 5 (A), one end of each board piece 4 is overlapped so as to come into contact with the end base material M, but when forming the second laminate, the end base material M is: It may or may not exist.
Similarly to the formation of the horizontal laminate 10, after the foam hardening of the board piece 4 immediately after spraying is completed, the next board piece 4 is stacked, and the vertical laminate 20 is formed to a desired height. It is preferable to release heat each time.

  After performing such overlapping of the board pieces 4 until the total thickness of the desired floating lid is reached, as illustrated in FIG. A floating lid 50 according to the second embodiment, which covers the upper surface of the first laminate 10 and is a combination of a laminate in the horizontal direction and a laminate in the vertical direction as shown in the schematic cross-sectional view of FIG. 6, is applied. .

Moreover, in the construction method of the floating lid which concerns on 2nd invention, the 2nd laminated body 20 can also be formed so that it may illustrate in FIG.
In the construction example shown in FIG. 7, the upper surface of the first laminate 10 is covered with the first layer board pieces 41, 41,. The board pieces 42, 42, ... are laminated. By repeating this, a substantially horizontal overlap with the liquid surface S is performed.
In this example, since another part can be constructed while the board piece immediately after spraying is dissipated while being foamed and cured, this is an effective method when the construction surface is large.

Furthermore, in the construction method of the floating lid according to the second invention, the second laminated body may be formed after covering all of the construction surface with the base layer or the first laminated body, and FIG. (B) and as shown in FIG. 7, after forming the base layer and the first laminate to some extent (that is, about two or three longitudinal laminates as shown in FIG. 5B and FIG. 7). The entire construction surface may be covered by repeating the cycle of forming the second laminate 20.
The place where the vertical second laminated body is formed on the horizontal first laminated body is further strengthened by the stress against the load from above, so that it can be put on by the installer. It becomes a scaffold. By using the scaffold, it is possible to easily extend the floating cover 50 (FIG. 6) according to the second invention as well as the first laminated body 10 including the remaining base layer 7 ′.

  In the floating lid construction method of the present invention, in the state where steam has come out from the liquid surface, water droplets may adhere to the surface of the end base material or board piece, and if sprayed there, a problem of poor adhesion occurs. Therefore, the liquid temperature is preferably room temperature or lower. In addition, there is no problem about raising the liquid temperature and generating steam after constructing the floating lid.

  A polyurethane foam stock solution A (NCO index: 120) and a polyurethane foam stock solution B (NCO index: 110) each having the following composition were respectively prepared:

≪Polyurethane foam concentrate A≫
[Polyol component]
● Polyether polyol 1 (hydroxyl value 600 mgKOH / g with ethylenediamine as an initiator, average functional group number 4) 70 parts by weight and polyether polyol 2 (hydroxyl value 350 mgKOH / g with toluenediamine as an initiator, average functional group number 3) ) Mixed polyol with 30 parts by weight: 100 parts by weight ● Blowing agent 1 (HFC-245fa): 20 parts by weight ● Blowing agent 2 (HFC-365mfc): 5 parts by weight ● Catalyst (Triethylenediamine (trade name, manufactured by Tosoh Corporation) "TEDA-L33")): 5 parts by weight ● Foam stabilizer (trade name “SH193” manufactured by Toray Dow Corning Co., Ltd.): 1.5 parts by weight ● Flame retardant (TMCPP (Trischloropropyl phosphate) / Daihachi Chemical Made by :) 20 parts by weight [polyisocyanate component]
-Polymeric MDI (polymethylene polyphenyl polyisocyanate) having an NCO content of 31% (trade name “MR-200” manufactured by Nippon Polyurethane Industry Co., Ltd.): 160 parts by weight

≪Polyurethane foam concentrate B≫
[Polyol component]
● Polyether polyol 1 (hydroxyl value 600 mgKOH / g with ethylenediamine as an initiator, average functional group number 4) 70 parts by weight and polyether polyol 2 (hydroxyl value 350 mgKOH / g with toluenediamine as an initiator, average functional group number 3) ) Mixed polyol with 30 parts by weight: 100 parts by weight ● Blowing agent 1 (HFC-245fa): 25 parts by weight ● Blowing agent 2 (HFC-365mfc): 10 parts by weight ● Blowing agent 3 (water): 2 parts by weight Catalyst (Triethylenediamine (trade name “TEDA-L33” manufactured by Tosoh Corporation)): 8 parts by weight ● Foam stabilizer (trade name “SH193” manufactured by Toray Dow Corning Co., Ltd.): 1.5 parts by weight ● Flame retardant ( TMCPP (trischloropropyl phosphate) / manufactured by Daihachi Chemical Co., Ltd.): 20 parts by weight [polyisocyanate component]
-Polymeric MDI (polymethylene polyphenyl polyisocyanate) having an NCO content of 31% (trade name “MR-200” manufactured by Nippon Polyurethane Industry Co., Ltd.): 170 parts by weight

  In a pool 3 m long x 2 m wide x 1 m deep, water is pooled to a depth of about 30 to 40 cm, and the polyurethane foam stock solution A or foam stock solution B and a substantially spherical foam having a diameter of 2 to 5 mm are formed on the water surface. Floating lids were constructed as follows using styrene beads (beaded by foaming beads having a diameter of 0.5-2 mm before foaming to a foaming ratio of about 2-10 times).

Experimental Examples 1 and 4 (floating lid according to the first invention)
As shown in FIG. 3A, the foamed styrene beads 6 were spread on the pool water surface S as floating pieces until the water surface was not exposed, and the entire water surface S was covered.
After that, the spraying operator sprays the spray gun G containing the polyurethane foam stock solution obliquely upward from the water surface as shown in FIG. 3 (B), and the stock solution 8 in the form of mist (fine particles) is obtained. Spraying was performed while moving a place about 2 to 3 m away from the floating piece 6 so as to fall on the floating piece 6, thereby forming an underlayer (thickness: about 3 to 6 cm) 7 ′ including the floating piece 6.
In Experimental Example 1, the polyurethane foam stock solution A was used, and in Experimental Example 4, the polyurethane foam stock solution B was used.

Next, as shown in FIG. 3C, a lateral laminate 10 is formed on the obtained base layer 7 ′.
A spraying operator discharges from the spray gun G toward the part 60-70 cm in which there is no water on the pool inner side surface M (the end base material M is the part on the inner side of the pool without water). The thickness (t) of the board piece 3 is adjusted while moving the spray gun G horizontally (left and right) so that the circular spray pattern of the polyurethane foam stock solution has a diameter (h) of about 25 cm and a width direction (w) of about 60 cm. The amount of spraying was about 2.5 cm.
The formation of the board piece 3 (h: about 25 cm × w: about 60 cm × t: about 2.5 cm) is defined as one span, and 20 spans are repeated while setting the interval for each span as a foam curing time for 10 to 20 seconds. The board pieces 3 are stacked in a direction substantially perpendicular to the water surface S, and the bottom area is about 50 cm << the thickness t of the board piece 3 x the number of spans >> x about 60 cm << the board piece 3 A laterally laminated body 10 having a lateral width w and a height of about 25 cm << the longitudinal width h of the board piece 3 >> was formed, and a floating lid 100 according to the first invention as shown in FIG. 4 was obtained.
As shown in Table 1, polyurethane foam stock solution A was used in Experimental Example 1, and polyurethane foam stock solution B was used in Experimental Example 4.

Experimental Examples 3 and 6 (floating lid according to the second invention)
In Experimental Example 3, the polyurethane foam stock solution A was used on the first laminate 10 of the floating lid 100 obtained in Experimental Example 1, and in Experimental Example 6, the first of the floating lid 100 obtained in Experimental Example 4 was used. On the laminated body 10, using the polyurethane foam undiluted solution B, respectively, it constructed as follows;
As shown in FIG. 5A, the spraying operator directs the spray gun G downward from above the first stacked body 10 in order to stack the board pieces 4 in a substantially horizontal direction with respect to the liquid level S. The thickness (t) of the board piece 4 while moving the spray gun horizontally (left and right) so that the circular spray pattern of the polyurethane foam stock solution has a diameter (h) of about 25 cm and a width direction (w) of about 60 cm. The amount of spraying was about 2.5 cm.
The formation of the board piece 4 (h: about 25 cm × w: about 60 cm × t: about 2.5 cm) is defined as 1 span, and 10 spans are repeated while setting an interval for each span as a foam curing time for 10 to 20 seconds. Then, the board pieces 4 are stacked substantially horizontally with respect to the water surface S, and the bottom area is about 25 cm << the vertical width h of the board piece 4 >> about 60 cm << the horizontal width w of the board piece 4 >> and the height is about 25 cm << Two laminates 20 in the vertical direction of the thickness t × the number of spans of the board pieces 4 were formed on the first laminate 10.
As shown in FIG. 5B, a “combination of forming two stacked bodies 20 and 20 in the vertical direction on the first stacked body 10” is one cycle (the bottom area is about 50 cm × 1 in this one cycle). By repeating 18 cycles, the entire water surface S (6 m ² ) of the pool is formed by approximately 60 cm, and the height (the total thickness of the base layer 7 ′ + laminate 10 + laminate 20) is approximately 53 to 56 cm). A floating cover 50 according to the second invention as shown in FIG.

  Table 1 schematically shows the types of foaming stock solutions used in the above experimental examples 1, 3, 4 and 6 and the structure of the rigid polyurethane foam laminate in the obtained floating lid (the experiments in Table 1). Examples 2 and 5 refer to those obtained by peeling off the second laminated body 20 of the floating lid 50 obtained in Experimental Examples 3 and 6 from the base layer 7 ′ and the first laminated body 10 as described later.

“Laminate 10 in the horizontal direction” obtained in the test examples 1 and 4 of the iron ball test , and “Laminate 20 in the vertical direction” obtained in the examples 3 and 6 (hereinafter referred to as examples 2 and 5). The iron ball (diameter of the combination of the lateral laminate 10 and the longitudinal laminate 20 (that is, the base layer 7 'peeled off from the floating lid 50) obtained in Experimental Examples 3 and 6) : 10 cm, weight: 4 kg) was dropped from a height of 100 cm from the upper surface of each laminate, and the state was visually evaluated.
The case where no dents, cracks or cracks occurred was rated as ◎, the case where dents or cracks were slightly generated but there were no practical problems, and the case where dents or cracks were largely generated was marked as Δ.
The results are also shown in Table 1.

Reference example 1
Using a polyurethane foam stock solution A similar to Experimental Example 1 and a spray gun, a circular spray pattern of the polyurethane foam stock solution has a diameter (h) of about 25 cm toward a commercially available plywood standing vertically to the floor in the factory. , While moving the spray gun in the horizontal (left and right) direction so that the width direction (w) is about 60 cm, spraying the amount of the board piece thickness (t) to about 3.0 cm, FIG. One test board piece 3 as shown was prepared.

Reference example 2
Except for using the same polyurethane foam stock solution B and spray gun as in Experimental Example 4, spraying was performed in the same manner as in Reference Example 1 to produce one test board piece 3 as shown in FIG.

Each “test board piece 3” obtained in Reference Examples 1 and 2 was designated as test specimens 1 and 4.
The “horizontal laminate 10” peeled off from the floating lid 100 obtained in the above-mentioned experimental examples 1 and 4 was used as test bodies 2 and 5, and the “longitudinal” peeled off from the floating lid 50 obtained in experimental examples 3 and 6 was used. The direction laminate 20 ”was designated as test bodies 3 and 6.
From these specimens 1 to 6, test pieces having the following dimensions and shapes were cut out, and for each cut out test piece, the density (kg / m ³ ), the dimensional change rate (%), the closed cell rate (%), and the compression Strength (N / cm ² ) and tensile elongation (%) were evaluated as follows:

-In "density" and "dimensional change rate", the block body of length 70mm x width 70mm x thickness 20mm was made into the test piece in the part containing a skin layer.
In the “closed cell ratio”, a block having a length (h) of 30 mm × width (w) of 30 mm × thickness (t) of 25 mm was used as a test piece.

-Regarding the "compressive strength", in the test bodies 1 and 4 (board piece 3) without the skin layer, a block body of length (h) 70 mm x width (w) 70 mm x thickness (t) 20 mm was used as the test piece.
In specimens 2, 3, 5, and 6 having skin layers, the test piece of lateral laminate 10 (test specimens 2 and 5) has four skin layers 3 'and longitudinal laminate 20 (test specimen 3). 6), the test piece was cut so that one skin layer 4 ′ was included, and a block body having a length of 100 mm × width of 100 mm × height of 30 mm was used as the test piece.
-Regarding the "tensile elongation", in the specimens 1 and 4 (board piece 3) having no skin layer, the shape described in JIS A9511 of length (h) 120 mm x width (w) 25 mm x thickness (t) 10 mm is used. A test piece was obtained.
In the test bodies 2, 3, 5, and 6 having the skin layer, the test piece of the lateral laminate 10 (test bodies 2 and 5) has five skin layers 3 'and the longitudinal laminate 20 (test specimen 3). 6), the test piece was cut to have one skin layer 4 'so that the same size and shape as those of the test pieces 1 and 4 were used.

The density (kg / m ³ ) was measured based on JIS K7222.
-Dimensional change rate (%) was measured based on ASTM D2126.
-The closed cell ratio (%) was measured based on ASTM D2856.
The compressive strength (N / cm ² ) was measured based on JIS K7220.
-Tensile elongation (%) was measured based on JIS A9511.
The results are also shown in Table 2.

In Experimental Examples 1, 4, 3, and 6 in which the underlayer was formed, it was not confirmed that liquid turbidity occurred or particulate polyurethane foam accumulated at the bottom.
From Tables 1 and 2, even when the compressive strength of the lateral laminate 10 is low (see the evaluation of compressive strength of the test specimens 2 and 5 in Table 2), the longitudinal laminate 20 formed from the same foaming stock solution. If the compression strength is excellent (refer to the evaluation of the compression strength of the test bodies 3 and 6 in Table 2), a strong floating lid 50 is obtained by combining the horizontal laminate 10 and the vertical laminate 20. (See the iron ball test evaluation of Experimental Examples 3 and 6 in Table 1).
Further, from Table 2, when the compressive strengths of the lateral laminate 10 (test bodies 2 and 5) and the longitudinal laminate 20 (test bodies 3 and 6) are compared, the lateral laminate 10 It has also been found that tends to be weaker than the compressive strength of the laminate 20 in the longitudinal direction.

The floating lid of the present invention has an excellent strength, has a very low water absorption rate and hardly swells, and can withstand long-term use outdoors.
In addition, the base layer existing between the floating lid and the liquid level prevents the unreacted polyurethane foam stock solution immediately after spraying from touching the liquid level and not only prevents liquid turbidity and contamination reliably. Since the formation of the underlayer is very easy, this is necessary when you want to urgently prevent the inflow of rainwater and sewage in the case of rain showers, etc. before construction of the floating lid, or to prevent the diffusion of dangerous odors urgently. An immediate response (first-aid treatment) can be performed on the underlayer, and a laminate on the first layer can be applied while the first-aid treatment is performed.
Therefore, for example, water and seawater, contaminated water (liquid waste), flammable liquids, fertilizer cover materials, as well as fireproof water for winter outdoor pool pollution prevention, ice fishing scaffolding, etc. It is also suitable as an outdoor athletic playground equipment.

10 Laminate in the horizontal direction (first laminate)
20 Longitudinal laminate (second laminate)
3 Board pieces juxtaposed in a substantially vertical direction with respect to the liquid surface 3 ', 4' Skin layers 4, 41, 42 Board pieces superposed in a substantially horizontal direction with respect to the liquid surface 6 Floating pieces 7, 7 'Underlayer 8 Adhesive material 100 Floating lid according to the first invention 50 Floating lid according to the second invention G Spray gun M End substrate S Liquid level t Board piece thickness h Vertical length of board piece w Horizontal width of board piece

Claims (5)

  A floating lid that is constructed on-site, and includes a base layer including a floating piece and a laminate made of a rigid polyurethane foam that is arranged in a direction substantially perpendicular to the liquid surface. It is a floating lid that is constructed on site,
An underlayer including a floating piece;
A first laminate made of rigid polyurethane foam juxtaposed in a direction substantially perpendicular to the liquid surface;
A floating lid comprising a second laminated body made of rigid polyurethane foam, which is arranged in a substantially horizontal direction with respect to the liquid surface on the first laminated body. A method for constructing the floating lid according to claim 1 by a spray method,
Form a base layer by covering the liquid surface with floating pieces,
Next, the polyurethane foam undiluted solution is sprayed toward the end base material side where the spray gun is erected on the liquid surface to form a laminate made of rigid polyurethane foam juxtaposed in a direction substantially perpendicular to the liquid surface. A method for constructing a floating lid. A method for constructing the floating lid according to claim 2 by a spray method,
Form a base layer by covering the liquid surface with floating pieces,
Next, the polyurethane foam stock solution is sprayed toward the end base material side where the spray gun is erected on the liquid surface to form a first laminate made of rigid polyurethane foam parallel to the liquid surface in a substantially vertical direction,
Furthermore, the polyurethane foam undiluted solution is sprayed with the spray gun directed from the upper side to the lower side of the first laminated body, and the second laminated body made of rigid polyurethane foam that is superposed in a substantially horizontal direction with respect to the liquid surface is the first laminated body. A method for constructing a floating lid, characterized by being formed on the top.   The floating piece is a foamed styrene bead or foamed urethane piece. The polyurethane foam stock solution is sprayed with the spray gun facing diagonally upward from the liquid surface, and the foamed styrene beads covering the liquid surface are fixed together to form an underlayer. The method for constructing a floating lid according to claim 3 or 4, wherein: