JP5863556B2 - Water absorption mat - Google Patents

Description

  The present invention relates to a water-absorbing mat, and more particularly, to a water-absorbing mat suitable for absorbing drip liquid that exudes from food.

  As a prior art related to this invention, a polystyrene resin foam sheet including an open cell foam layer having an open cell ratio of 60% or more and a closed cell foam layer having an open cell ratio of 30% or less is molded. The obtained polystyrene-based resin foamed plate is a water-absorbing polystyrene-based resin foamed plate that is improved in water absorption by forming an open-celled foamed layer so as to have a foaming ratio of 1.5 times or more. It is known (see, for example, Patent Document 1).

  Further, as a further prior art related to the present invention, a water absorption hole forming step of forming a plurality of water absorption holes reaching the open cell foam layer in a resin foam sheet having an open cell foam layer, and a water absorption hole are formed. The water-absorbent foam which improved the moldability by performing the process of making the resin foam sheet secondary foamed, and the thermoforming process of thermoforming the secondary foamed resin foam sheet into a desired shape continuously. A method for manufacturing a molded product is known (see, for example, Patent Document 2).

JP 2008-239852 A JP 2012-30509 A

Traditionally, food trays have been used to store and display food at retail stores such as fresh food stores.
Depending on the type of food stored, in fresh foods such as raw meat and sashimi, the liquid called drip liquid that spilled from the destroyed cells is likely to exude, and if it remains immersed in the drip liquid, Deterioration easily proceeds.
For this reason, when containing foods that easily drip liquid drip, usually, a water absorbent sheet called a drip sheet that absorbs drip liquid is laid on the bottom of the food tray, and food is placed on the water absorbent sheet. Consideration has been made.

However, in the above-described method, although it is good if the drip liquid is small, if the drip liquid is large, the drip liquid cannot be absorbed by the water absorbent sheet, and there is a possibility that the food remains immersed in the drip liquid. is there.
Further, although depending on the performance of the water absorbent sheet, the drip liquid once absorbed by the water absorbent sheet may ooze out of the water absorbent sheet again, and the drip liquid may be in contact with the food.
Therefore, there is a need for an alternative to a water-absorbent sheet that can reliably prevent food from being dipped into or contacting the drip liquid.

  The present invention has been made in view of the above circumstances, and provides an improved water-absorbing mat that can surely prevent food from being immersed in or coming into contact with drip liquid.

  The present invention includes a food placing portion formed by molding a resin foam sheet having an open-celled foam layer into a plate shape, and the food placing portion has a water-absorbing hole or a water-absorbing slit reaching the open-celled foam layer. The present invention provides a water absorbent mat characterized by having an undulating portion.

According to this invention, since the water absorption hole or the water absorption slit leading to the open cell foam layer is formed in the food placing portion having the undulating portion, the water absorption mat according to the present invention is laid on the bottom of the food tray and placed thereon When food is placed, not only can the drip liquid that exudes from the food be absorbed into the open cell foam layer through the water absorption holes or the water absorption slits, but the contained food can be lifted from the bottom of the food tray.
For this reason, even if there is a lot of drip liquid that exudes from the food and it cannot be absorbed by the open cell foam layer, the drip liquid that could not be absorbed will accumulate at the bottom of the food tray, and the food lifted from the bottom of the food tray Do not touch.
Therefore, it is possible to reliably prevent the food stored in the food tray from being dipped into or coming into contact with the drip liquid, and to be displayed hygienically.

1 is a perspective view of a water absorbent mat according to an embodiment of the present invention. It is a front view of the water absorption mat shown by FIG. It is AA arrow sectional drawing of FIG. It is the B section enlarged view of FIG. It is explanatory drawing which shows the state which spread | laid the water absorption mat which concerns on embodiment of this invention on the bottom of the food tray, and mounted the foodstuff. In the water absorption mat which concerns on embodiment of this invention, it is explanatory drawing explaining the setting method of the height and width | variety of a waveform part. In the water absorption mat which concerns on embodiment of this invention, it is explanatory drawing explaining the setting method of the height and width | variety of a waveform part. It is explanatory drawing explaining the manufacturing method of the water absorbing mat which concerns on embodiment of this invention. It is a perspective view of the water absorption mat which concerns on the modification 1 of this invention. FIG. 10 is a front view of the water absorbent mat shown in FIG. 9. It is CC sectional view taken on the line of FIG. It is explanatory drawing which shows the state which spread | laid the water absorption mat which concerns on the modification 1 on the bottom of the food tray, and mounted the foodstuff. It is a perspective view of the water absorption mat which concerns on the modification 2 of this invention. It is DD sectional view taken on the line of FIG. It is the E section enlarged view of FIG.

  The water absorbent mat according to the present invention includes a food placing portion formed by molding a resin foam sheet having an open cell foam layer into a plate shape, and the food placing portion has a water absorption hole or a water absorption slit reaching the open cell foam layer. It has the undulation part formed.

  The water-absorbing mat according to the present invention is not intended only for water absorption, but is widely intended for absorption of liquids in general. Therefore, the water absorption holes or the water absorption slits formed in the food placing portion are not intended to suck water but are intended to suck the entire liquid.

  In the water absorbent mat according to the present invention, as the resin foam sheet having an open-cell foam layer, a conventionally known resin foam sheet can be used. For example, a resin composition mainly composed of polyethylene resin or polypropylene resin is foamed. Polyolefin resin foam sheets that are extruded, styrene homopolymers, and resin compositions based on polystyrene resins such as monomers and styrene copolymers that can be copolymerized with styrene are foam extruded. A polystyrene-based resin foam sheet or the like can be used.

Here, the open-celled foam layer is a foam layer having a large number of open cells that are in communication with each other due to tearing of the cell membrane between adjacent cells, and water (drip liquid) that has absorbed the continuous cells. ) Storage space.
The standard for the open cell ratio is not particularly limited, but is preferably about 60 to 90% as measured by the measurement method described in ASTM D2856-87. This is because if the open cell ratio is lower than about 60%, the water absorption performance becomes insufficient, and if it exceeds about 90%, the mechanical strength becomes too low.

  When a polystyrene resin foam sheet is used as the resin foam sheet having an open-cell foam layer, examples of the resin composition constituting the polystyrene resin foam sheet include a styrene homopolymer called general-purpose polystyrene resin (GPPS). And a hydrogenated product of a copolymer of styrene and conjugated diene, and a mixture of a polyolefin resin and a foaming component.

Here, examples of the conjugated diene include conjugated dienes having 4 to 10 carbon atoms such as butadiene, isoprene, and 2-ethylbutadiene. Preferred hydrogenated styrene-conjugated diene copolymers include styrene-isoprene. Examples thereof include a hydrogenated product of a block copolymer, a hydrogenated product of a styrene-butadiene block copolymer, and a hydrogenated product of a styrene-butadiene random copolymer.
In addition, the polyolefin resin is a component that facilitates the formation of open cells by foaming in the cell membrane during foaming. Examples of the polyolefin resin include high-density polyethylene resin and polypropylene resin. Can be used.

  The ratio of the polystyrene resin, the hydrogenated copolymer of styrene and conjugated diene, and the polyolefin resin is usually 50 to 94% by weight of polystyrene resin and styrene when the total amount is 100% by weight. The hydrogenated copolymer of conjugated diene is selected from the range of 5 to 49% by mass, and the polyolefin resin is selected from the range of 1 to 10% by mass.

In addition, as the above foaming components, there are foam regulators such as inorganic fillers such as talc, mica and montmorillonite, organic fine particles such as fluororesin, hydrocarbons such as propane, isobutane, normal butane and pentane, nitrogen, It can be used in combination with a blowing agent such as an inert gas such as carbon dioxide.
Among them, as a foaming agent, mixed butane in which isobutane and normal butane are mixed in a ratio of 50:50 to 80:20 is taken into consideration when foaming properties are produced during the production of the resin foam sheet (at the time of primary foaming) and at the time of secondary foaming. Is preferred.

The resin foam sheet having the above-mentioned open-celled foam layer may have a laminated structure of an open-cell foam layer and a closed-cell foam layer. When the resin foam sheet has a closed cell foam layer in addition to the open cell foam layer, the mechanical strength after molding can be improved, and food can be stably placed on the food placing portion.
In this case, as long as the water absorption hole or the water absorption slit is formed so as to reach the open cell foam layer, it may be formed on either the open cell foam layer side or the closed cell foam layer side, or the continuous cell foam layer. It may be formed on both the cellular foam layer side and the closed cell foam layer side. However, from the viewpoint of shortening the water absorption path, it is preferably formed on the open-celled foam layer side.

When the resin foam sheet has a laminated structure of an open-cell foam layer and a closed-cell foam layer, as the resin composition constituting the closed-cell layer, for example, the above-mentioned foam component is blended with general-purpose polystyrene resin (GPPS). Can be used.
The resin foam sheet having such a laminated structure is obtained by melting and kneading the resin composition constituting the open-celled foam layer and the resin composition constituting the closed-cell foamed layer with separate extruders and joining them together. It is obtained by coextrusion from a circular die.
The continuous foaming ratio of the closed-cell foamed layer is not particularly limited, but about 0 to 30% is preferable from the viewpoint of mechanical strength after molding as measured by the measurement method described in ASTM D2856-87. .
In addition, when the resin foam sheet has a laminated structure of an open-cell foam layer and a closed-cell foam layer, the thickness of the open-cell foam layer is about 0.5 to 1.5 mm before secondary foam, The thickness of the foam layer can be about 1 to 3 mm before secondary foaming.

In the water absorbent mat according to the present invention, the undulating portion may have a waveform in which a plurality of hook-shaped protrusions are arranged in parallel.
According to such a configuration, not only can the mechanical strength of the water absorbent mat be improved, but also the food can be supported by a plurality of hook-shaped protrusions, so that the pressure applied to the food is dispersed and the shape of the food is not destroyed. It can be placed stably.

In the above configuration in which the undulating portion is corrugated, the bowl-shaped protrusions may be formed on one surface side and the other surface side of the food placing portion, respectively.
According to such a configuration, the height difference from the apex of the protrusion formed on one surface side of the food placing portion to the apex of the protrusion formed on the other surface side of the food placing portion increases, Can be lifted high from the bottom of the food tray. As a result, it is possible to more reliably prevent the food from being immersed in or coming into contact with the drip liquid.

In the above configuration in which the undulating portion is corrugated, each of the hook-shaped protrusions may have a height in the range of about 20 to 50% of the width.
According to such a structure, a resin foam sheet can be shape | molded reasonably and the intensity | strength of the whole water absorption mat can be maintained appropriately.
This is because when the height of each bowl-shaped protrusion is set to a height exceeding about 50% of the width, the resin foam sheet is folded at the apex portion of the protrusion during molding due to the property of the resin foam sheet. This is because the thickness becomes extremely thick in the vicinity of the apex of the protrusion, while the portion between adjacent protrusions is excessively stretched and the thickness becomes thin.

If the thickness between adjacent protrusions becomes thin, the strength of the entire water-absorbing mat cannot be maintained properly, and it is easy to crack or bend at the thin part when subjected to a strong load. It becomes difficult to apply to food.
On the other hand, when the height of each bowl-shaped protrusion is set to a height lower than about 20% of the width, the action of lifting the food from the bottom of the food tray is insufficient, so that the food is immersed in or comes into contact with the drip liquid. It is difficult to obtain the effect of the present invention for preventing the above.
For this reason, it is preferable that the height of each hook-shaped protrusion is in the range of about 20 to 50% of the width.

  Hereinafter, a water absorbing mat and a method for manufacturing the same according to an embodiment of the present invention will be described with reference to the drawings.

  A foamed resin tray according to an embodiment of the present invention will be described with reference to FIGS. 1 is a perspective view of a water absorbent mat according to an embodiment of the present invention, FIG. 2 is a front view of the water absorbent mat shown in FIG. 1, FIG. 3 is a cross-sectional view taken along the line AA in FIG. Fig. 5 is an enlarged view of part B, Fig. 5 is an explanatory view showing a state in which the water absorbent mat according to the embodiment of the present invention is laid on the bottom of the food tray, and food is placed thereon, and Figs. 6 and 7 are water absorbent mats according to the embodiment of the present invention. FIG. 3 is an explanatory diagram for explaining a method of setting the height and width of the waveform portion.

As shown in FIGS. 1 to 3, the water absorbent mat 1 according to the embodiment of the present invention is a food product formed by molding a resin foam sheet 30 (see FIG. 8) having an open-cell foam layer 31 into a plate shape. Part 2 is provided. The food placing portion 2 has an undulating portion 4 in which a water absorption hole 3 reaching the open-celled foam layer 31 is formed.
The undulating portion 4 has a waveform in which a plurality of bowl-shaped projections 5 are arranged in parallel, and the projections 5 are formed on one surface side 2a and the other surface side 2b of the food placing portion 2, respectively.

As shown in FIG. 3, the water absorbent mat 1 has a laminated structure of an open cell foam layer 31 and a closed cell foam layer 32. The open-celled foam layer 31 is a foamed layer having a large number of open cells that are in communication with each other due to tearing of the bubble film between adjacent cells, and stores water (drip liquid) that has absorbed the continuous cells. It can be used as a space.
On the other hand, the closed-cell foam layer 32 is a foam layer having a large number of independent bubbles in which the bubble film is not broken, and is a layer having excellent mechanical strength.

As described above, the water-absorbing mat 1 has a laminated structure of the open-cell foam layer 31 and the closed-cell foam layer 32, so that the open-cell foam layer 32 is used while the open-cell foam layer 31 is used as the water-absorbing layer. Therefore, the mechanical strength of the entire water absorbent mat 1 can be ensured.
In FIG. 3, the boundary between the open-cell foam layer 31 and the closed-cell foam layer 32 is clearly depicted, but actually, the boundary between the open-cell foam layer 31 and the closed-cell foam layer 32 is continuous. The foaming rate is changing gradually and no clear boundary appears.

Further, as shown in FIG. 4, a surface skin layer 31 a having a high closed cell ratio and a small cell diameter is formed on the surface side of the open cell foam layer 31. Since the surface skin layer 31a is formed by densely forming independent bubbles having small bubble diameters, the surface skin layer 31a is usually hydrophobic and impermeable to water.
For this reason, the water absorption holes 3 are formed so as to penetrate the surface skin layer 31 a and reach the open cell foam layer 31.

As shown in FIG. 5, when the water absorption mat 1 according to the present embodiment is laid on the bottom 50 a of the food tray 50 and the food F such as meat is placed thereon, the food F is one of the food placing portions 2. It is supported by the protrusion 5 formed on the surface side 2a.
At this time, since the food F is supported by the plurality of protrusions 5, the food F is stably placed on the water absorbent mat 1.
The drip liquid (not shown) exuding from the food F is absorbed by the open cell foam layer 31 through the water absorption holes 3 and stored in the open cell (not shown) of the open cell foam layer 31.
Here, since the water absorption holes 3 are formed on the open cell foam layer 31 side, the water absorption path is shortened as compared with the case where the water absorption holes 3 are provided on the closed cell foam layer 32 side.
For this reason, the drip liquid exuded from the food F is quickly absorbed by the open-celled foam layer 31 through the water absorption holes 3.

Even if the drip liquid cannot be absorbed by the open-cell foam layer 31 and the drip liquid is accumulated on the bottom 50a of the food tray 50, the food F is absorbed by the water-absorbing mat 1 at the bottom 50a of the food tray 50. The food F is not soaked in or in contact with the drip liquid.
Here, in this embodiment, since the projection 5 is also formed on the other surface side 2b of the food placing portion 2, from the apex of the projection 5 formed on the one surface side 2a to the other surface side 2b. The difference in height to the top of the formed protrusion 5 is large, and the food F is lifted from the bottom 50a of the food tray 50 at a sufficient height.

  Here, a method of setting the height H1 and the width W1 (see FIG. 2) of the protrusion 5 will be described with reference to FIGS. 6 and 7 are explanatory diagrams for explaining a method of setting the height and width of the corrugated portion in the water absorbent mat according to the embodiment of the present invention.

As shown in FIG. 6A, a case is considered in which a corrugated protrusion is heat-molded by sandwiching a resin foam sheet with a mold 60 composed of a pair of male mold 61 and female mold 62.
The part corresponding to the corrugated protrusion can be assumed to be a shape in which the bases (b) of two right triangles are in contact with each other and the opposite side (a) is connected in the same straight line.
Here, since the resin foam sheet is an aggregate of a large number of bubbles, it is difficult to form a sharp shape due to its property, and the angle θ formed between the base (b) and the hypotenuse (c) of the right triangle is about 20 If the angle is limited, and the angle θ is smaller than 20 °, the molding is hindered.
For this reason, when the resin foam sheet is thermoformed into a corrugated protrusion shape, it is necessary to set the inner angle of the apex of the protrusion to at least 40 ° or more.

In addition, since the resin foam sheet is preliminarily formed into a sheet shape, if it is heat-molded into a corrugated protrusion shape, the resin foam sheet is folded at a portion corresponding to the top of the corrugation.
For this reason, as shown in FIG. 6B, the heat-molded resin foam sheet 70 has a thickness T2 that is about twice the thickness T1 of the resin foam sheet at the top of the corrugation.
In other words, when trying to heat-mold the corrugated protrusion with the inner angle of the apex being 40 °, a height H2 at least twice the thickness T1 of the resin foam sheet 70 is naturally obtained.

In addition, the resin foam sheet 70 heat-molded into a corrugated protrusion shape is excessively stretched so that the vicinity of the protrusion (rising part) is drawn into the apex part as the apex part becomes thicker. Insufficient mechanical strength near the root of
Such a phenomenon is more likely to occur as the ratio of the height to the width of the corrugated protrusion becomes higher. In the example shown in FIG. 6B, the height H2 of the corrugated protrusion is about 100% of the width W2. ing.

For this reason, when the inner angle of the apex of the protrusion is set to 40 °, it is necessary to increase the width W2 with respect to the height H2 of the protrusion that is necessarily obtained.
Further, in the present embodiment, the protrusion 5 formed on the food placing portion 2 is a portion in contact with the food F, and in order to prevent the food F from being damaged, the curvature radius of the apex portion of the protrusion 5 is increased, and the food It is preferable to lower the contact pressure for F.

From the above knowledge, in this embodiment, as shown in FIG. 7A, a corrugated protrusion is thermoformed by sandwiching a resin foam sheet with a mold 80 comprising a pair of male mold 81 and female mold 82. At this time, an appropriate distance D1 is set between the bases (b) so that the bases (b) of the right triangles are separated from each other.
Accordingly, as shown in FIG. 7B, the ratio of the height H3 to the width W3 of the resin foam sheet 90 heat-molded into the corrugated protrusion shape is reduced, and the resin foam sheet 90 is excessively stretched near the base of the protrusion. The appropriate wall thickness is maintained as a whole. In addition, the radius of curvature at the apex portion increases, and the contact pressure with respect to the food F decreases.

  In the example shown in FIG. 7A, the interval D1 provided between the bases (b) of the right triangle is 20 to 50 in which the height H1 of the corrugated protrusion 5 shown in FIG. % Is preferably set from the viewpoint of securing the overall mechanical strength of the water absorbent mat 1 (see FIG. 1). In the present embodiment, the height H1 of the protrusion 5 is about 30% of the width W1.

As described above, the method of setting the height H1 and the width W1 of the protrusion 5 has been described by taking the case where the inner angle of the vertex of the protrusion is 40 °. However, such knowledge is obtained when the inner angle of the vertex of the protrusion is 40 °. The present invention is not limited, and can be widely applied when the inner angle of the apex of the protrusion is about 40 to 120 °.
However, as the inner angle of the protrusion apex increases, the ratio of the height to the protrusion width decreases, and excessive stretching near the root of the protrusion is less likely to occur.Therefore, the above setting method decreases the inner angle of the protrusion apex. This is particularly useful when setting.
As the inner angle of the apex of the protrusion is set smaller, the interval between the adjacent protrusions 5 can be reduced, and the number of contact points with the food F can be increased. For this reason, setting the inner angle of the apex of the protrusion small is effective in reducing the contact pressure with respect to the food F and placing the food F in a more stable state.

  A method for manufacturing the water absorbent mat 1 having the above-described configuration will be described with reference to FIG. FIG. 8 is an explanatory view illustrating a method for manufacturing a water absorbent mat according to an embodiment of the present invention.

As shown in FIG. 6, the molding machine 20 includes a heating furnace 21 that heats the resin foam sheet 30 before molding, and a pair of male mold 23 and female mold 24 that sandwich the heated resin foam sheet 30 from above and below. The die 22 and the cutter (not shown) for cutting out the individual water-absorbing mats 1 from the molded resin foam sheet 30 are mainly configured.
Although not shown, each of the male mold 23 and the female mold 24 is connected to a vacuum pump and configured to be able to perform vacuuming from a number of fine vacuum holes formed on the surface. Further, the male mold 23 and the female mold 24 are configured to be moved up and down by cylinder mechanisms 27 and 28, respectively.

The molding machine 20 is set with a raw roll R1 obtained by winding a polystyrene-based resin foam sheet (PSP sheet) having a laminated structure of an open cell foam layer and a closed cell foam layer as a raw material.
The resin foam sheet 30 fed out from the raw roll R1 is passed between a pair of perforating rollers 25 and a support roller 26 disposed so as to face each other.

The perforating roller 25 has a structure in which a large number of needles (not shown) having a length substantially equal to the thickness of the open-cell foamed layer protrude from the surface, and is resinous with respect to the support roller 26 having a flat peripheral surface. The foam sheets 30 are opposed to each other with an interval substantially equal to the thickness of the foam sheet 30.
The resin foam sheet 30 passed between the perforation roller 25 and the support roller 26 has a large number of holes formed by the needles of the perforation roller 25 and is then passed through the heating furnace 21 to be heated and subjected to plasticization and secondary foaming. Begins.

The resin foam sheet 30 exiting from the heating furnace 21 is passed between a pair of male mold 23 and female mold 24 and sandwiched between the male mold 23 and female mold 24. At this time, evacuation is performed by the male mold 23 and the female mold 24, and the resin foam sheet 30 is quickly heat-formed following the shape of the male mold 23 and the female mold 24.
Then, after the male mold 23 and the female mold 24 are disengaged and the shape is stabilized by cooling, a series of steps is completed by cutting the individual water absorbent mats 1 with a cutter (not shown).

[Modification 1]
Modification 1 of the water absorbent mat according to the present invention will be described with reference to FIGS. 9 is a perspective view of a water absorbent mat according to a first modification of the present invention, FIG. 10 is a front view of the water absorbent mat shown in FIG. 9, FIG. 11 is a sectional view taken along the line CC of FIG. 9, and FIG. It is explanatory drawing which shows the state which spread | laid the water absorption mat which concerns on 1 on the bottom of a food tray, and mounted the foodstuff.

  As shown in FIGS. 9 to 11, the water absorbent mat 101 according to the first modification of the present invention is formed such that a plurality of bowl-shaped protrusions 105 are arranged in parallel only on one surface side 102 a of the food placing portion 102. The other surface side 102b is flat. Other configurations are the same as those of the water absorbent mat 1 (see FIG. 1) according to the above-described embodiment.

Since the other surface side 102b of the water absorbent mat 101 according to the modified example 1 is flat, the water absorbent mat 101 is laid on the bottom 150a of the food tray 150 as shown in FIG. , The drip liquid oozed out from the food F is quickly absorbed into the open cell foam layer 31 not only from the water absorption holes 103 formed in the food placement portion 102 but also from the side surface 101a of the water absorption mat 101.
For this reason, the water absorption mat 101 which concerns on the modification 1 is used suitably with respect to the foodstuff F by which quick absorption of drip liquid is calculated | required.

[Modification 2]
Modification 2 of the water absorbent mat according to the present invention will be described with reference to FIGS. 13 is a perspective view of a water absorbent mat according to Modification 2 of the present invention, FIG. 14 is a cross-sectional view taken along the line DD in FIG. 13, and FIG. 15 is an enlarged view of a portion E in FIG.

As shown in FIGS. 13 to 15, the water absorbent mat 201 according to the second modification of the present invention has a V-shaped planar view of the water absorbent holes 3 in the plan view of the water absorbent mat 1 (see FIG. 1) according to the first embodiment. A water absorption slit (cut) 203 is substituted. Other configurations are the same as those of the water absorbent mat 1 according to the first embodiment.
As shown in FIGS. 14 and 15, the water absorption slit 203 is formed so as to penetrate the surface skin layer 31 a and reach the open-celled foam layer 31. Accordingly, when food such as meat is placed on the water absorbent mat according to the second modification, the drip liquid oozed out from the food is quickly absorbed into the open cell foam layer 31 through the water absorbent slit 203.

  In the modified example 2, the water-absorbing slit 203 having a V-shape in plan view is adopted instead of the water-absorbing holes 3 of the water-absorbing mat 1 according to the first embodiment, but the shape of the water-absorbing slit is not limited to this and is U-shaped in plan view. Various shapes of water absorption slits such as an I-shape in plan view can be adopted. Further, these water absorption slits may be employed instead of the water absorption holes 103 of the water absorption mat 101 according to the first modification.

  As described above, the water absorbent mat according to the present invention has been described in detail. However, the water absorption hole and the water absorption slit formed in the food placing portion are not limited to either one, and the water absorption hole and the water absorption slit are used in combination. May be. Moreover, the water absorbing mat according to the present invention can be suitably used not only as a rug for food trays but also for various uses that require quick water absorption.

DESCRIPTION OF SYMBOLS 1,101,201 Water absorption mat 2,102 Food placing part 2a, 102a One surface side 2b, 102b The other surface side 3,103 Water absorption hole 4 Uneven part 5,105 Protrusion 20 Molding machine 21 Heating furnace 22,60, 80 Molds 23, 61, 81 Male dies 24, 62, 82 Female dies 25 Punch rollers 26 Support rollers 27, 28 Cylinder mechanisms 29a, 29b Heat rolls 30, 70, 90 Resin foam sheet 31 Open-cell foam layer 31a Surface skin Layer 32 Closed cell foam layer 50, 150 Food tray 50a, 150a Bottom 203 Water absorption slit R1 Raw roll

Claims (4)

It is provided with a food placement part formed by molding a resin foam sheet having an open-celled foam layer into a plate shape, and the food placement part has an undulating portion in which a water absorption hole or a water absorption slit leading to the open-cell foaming layer is formed. And when the food placing part is installed in the container so that the peripheral part of the food placing part has a flat structure and the peripheral part is parallel to the flat bottom of the container, the peripheral part is A water-absorbing mat characterized by being separated from the bottom of the container or in contact with the bottom of the container .   The water absorption mat according to claim 1, wherein the undulating portion has a waveform in which a plurality of hook-shaped protrusions are arranged in parallel.   The water-absorbing mat according to claim 2, wherein the bowl-shaped protrusions are formed on one surface side and the other surface side of the food placing portion, respectively.   The water absorbent mat according to claim 2 or 3, wherein each of the hook-shaped protrusions has a height within a range of 20 to 50% of the width.