JP2009171849A - Gardening moisture-retaining bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gardening moisture-retaining bag effectively preventing decomposition of water-absorbing polymer due to ultraviolet rays so as to exert the favorable moisture-retaining effect of soil over a long period of time. <P>SOLUTION: The gardening moisture-retaining bag 1 is structured as follows: a prescribed amount (around 0.5 g in terms of dry weight) of polymer powder 10 comprising unhydrated moisture-retaining material is put between rectangular two pieces of a top surface sheet 3 and an under surface sheet 4; and the four peripheral sides of both of the sheets 3, 4 are sealed at peripheral parts 30, 40 to be internally sealed up. The polymer powder 10 absorbs water to be formed into hydrated gel 10x and appropriate numbers of the gardening moisture-retaining bags 1 are placed on the surface of the soil. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gardening moisturizing bag, and more particularly to a technique for preventing ultraviolet decomposition of a water-absorbing polymer.

  Water-absorbing polymers represented by polyvinyl alcohol (PVA) and polyacrylate (PA) can absorb water several tens to several hundred times more than their own weight, and are widely used in disposable diapers and sanitary products. . Recently, water-absorbing gel-like water-absorbing polymers that have absorbed water are becoming popular as a means for keeping moisture in the environment and keeping it cool for a relatively long period of time (Patent Document 1).

In this new use, in addition to being applied to transport containers for storing processed foods, building materials, clothing, etc., it is also used for horticultural purposes (Patent Document 2). For horticultural use, it is used by directly mixing in the soil to give a moisturizing effect to the soil (Patent Document 3), or by packaging the water-absorbing polymer with a breathable exterior body and containing water. It is used in the form by being placed on the soil surface.
Japanese National Patent Publication No. 11-505468 Japanese Patent Laid-Open No. 2005-270958 JP-A-9-252664 Japanese Patent No. 3336037

However, the water-absorbing polymer has low resistance to ultraviolet rays, and there is a problem of durability when the moisturizing bag is used outdoors for gardening. When a moisturizing bag placed on the soil surface is exposed to sunlight for a long period of time, it is affected by ultraviolet rays (UV, VUV, etc.) of each wavelength region in the sunlight, and the crosslinked portion of the polymer structure is decomposed. .
When the water-absorbing polymer is decomposed, the water content is reduced, and sufficient water absorption and a moisturizing effect due to this cannot be exhibited. Further, when the crosslinked structure of the water-absorbing polymer is broken, low molecules are generated, and there is a problem that the low molecules leak out to the outside from the holes on the surface of the moisture retaining bag.

Such problems can occur in just a few days from the start of use. Therefore, it is a problem to be solved particularly when the horticultural moisturizing bag is used in a region or season where the ultraviolet intensity is relatively high, or in an environment where the sunlight is shined for a long time.
The present invention has been made in view of the above problems, and even when used outdoors, by effectively preventing the decomposition of the water-absorbing polymer by ultraviolet rays, it exhibits a good soil moisturizing effect over a long period of time. An object of the present invention is to provide a moisturizing bag for gardening that can be used.

In order to solve the above problems, the present invention provides a horticultural moisturizing bag in which a water-absorbing polymer-containing material is enclosed in a breathable bag body, wherein at least one surface of the bag body is an ultraviolet ray. It was comprised with the UV cut sheet | seat which interrupts | blocks incidence | injection, and it was set as the structure which the other surface has a moisture permeability.
Here, “one surface” refers to one of the surfaces when the bag body has a flat shape such as an envelope. Further, when the bag body has a spherical shape or the like with a volume, the surface can be seen from any one direction.

“UV cut” refers to a function of blocking the UV transmittance by 60% or more.
Further, the UV cut sheet may be configured to have air tightness and liquid tightness.
Furthermore, the UV cut sheet may be configured such that an ultraviolet blocking material is mixed or laminated on the surface of the resin component. The ultraviolet blocking material is preferably at least one of carbon, aluminum, and titanium oxide.

Or if the said UV cut sheet is comprised with the colored woven fabric or the nonwoven fabric, this invention can be implement | achieved cheaply.
The present invention is a horticultural moisturizing bag in which a water-absorbing polymer-containing material is enclosed in a bag having air permeability, and the containing material includes a material for preventing ultraviolet decomposition of the water-absorbing polymer. It can also be set as the structure in which the decomposition inhibitor is contained.

In this case, the decomposition inhibitor may be at least one of a benzotriazole compound, a benzophenone compound, a salicylate compound, and the like.
In the present invention, the water-absorbing polymer can be at least one of polyacrylate, polyvinyl alcohol, and polyisopropylamide.
Moreover, this invention set it as the cultivation method of the plant body which supplies a water | moisture content to the plant planted in the said soil by mounting the said moisturizing bag for gardening in soil.

  In this invention which has the above structure, when using a moisturizing bag, it mounts on the soil surface etc. by making a UV cut sheet into the upper surface side, and making the surface which has a water permeability into the lower surface side. As a result, the ultraviolet rays in the sun rays are blocked by the UV cut sheet and do not enter the inside of the moisturizing bag, so that the water-absorbing polymer constituting the water-containing gel is irradiated with ultraviolet rays as in the past, and the crosslinked structure is decomposed. Can be prevented. Therefore, a stable polymer structure is maintained even outdoors, and the sustained release of moisture is continuously exhibited. Therefore, even if the use under sunlight is continued, a good soil moisturizing effect due to the water-absorbing polymer can be expected. Further, by periodically absorbing water in a dry moisturizing bag, the same moisturizing effect as in the initial use can be exhibited any number of times, and an extremely useful moisturizing bag is realized.

  Furthermore, in the present invention, the moisture evaporation region of the moisturizing bag can be controlled by imparting air tightness and liquid tightness to one surface of the bag body and imparting moisture permeability to the other surface. That is, by disposing the moisture permeable surface on the soil side and arranging the other surface on the upper surface side, it is possible to prevent evaporation of moisture from the upper surface side, which is unnecessary for moisturizing the soil. For this reason, it becomes possible to give a water | moisture content only to the soil which wants to moisturize, and efficient water | moisture-content sustained release property is exhibited. Thereby, the moisturizing effect by the moisturizing bag can be expected over a long period of time even in a warm place where the sun shines.

  Further, in the present invention, when a black ultraviolet blocking material such as carbon is used for the UV cut sheet, a slight heat storage action is performed by receiving sunlight, so that the effect of warming the soil surface is also achieved. In this case, as in the case of so-called multi-sheets, it is useful when growing crops that are relatively weak at low temperatures.

Embodiments of the present invention will be described below, but the present invention is naturally not limited to these embodiments, and can be appropriately modified and implemented without departing from the technical idea of the present invention. it can.
Of course, the embodiments can be combined with each other within a consistent range.
<Embodiment 1>
FIG. 1 is a diagram showing a configuration of a gardening moisturizing bag (hereinafter referred to as “humidifying bag 1”) according to the first embodiment of the present invention. Fig.1 (a) shows the external view of a moisture retention bag, FIG.1 (b) shows the assembly drawing of a moisture retention bag, respectively.

  The moisturizing bag 1 is a fixed amount (about 0.5 g in dry weight) of the polymer powder 10 that is a moisturizing material before water content between the two rectangular upper sheet 3 and lower sheet 4 forming the bag. It is filled and sealed around the four sides of both sheets 3, 4 by thermocompression bonding at the peripheral portions 30, 40. The drying size of the moisturizing bag 1 can be about 12 cm long side × 6 cm short side × 1 mm thickness. The polymer powder 10 preferably has an average particle size of about 100 to 200 μm, and the amount used is set in consideration of the expansion volume when containing water.

  The top sheet 3 is a non-transparent resin film excellent in airtightness and liquid-tightness with a thickness (100 μm), and is made of carbon black having an effect of blocking ultraviolet rays incident from the outside on the main component polyethylene. This is a dispersed UV cut sheet. The air tightness and liquid tightness of the film prevent wasteful water evaporation from the surface of the top sheet 3 and efficiently guide water absorbed by the water-absorbing polymer to the bottom sheet 4 side. Carbon black is used to prevent sodium polyacrylate from being decomposed by being irradiated with ultraviolet rays when the moisturizing bag 1 is used outdoors in the presence of sunlight.

  The carbon black is not essential, and other known UV cut means may be applied to the top sheet 3. For example, an aluminum vapor deposition film can be laminated on at least one surface of a polyethylene film. Further, a metal oxide such as titanium oxide that scatters incident light from the outside may be dispersed in the polyethylene film. In addition, it is also possible to use a known transparent UV cut film (“Heat ray blocking film RS” series manufactured by Galware Inc. as an example of a commercially available product).

By using a transparent film or relatively reducing the amount of impurities dispersed in the polyethylene film, there is an advantage that the moisture content of the water-absorbing polymer inside the humidity control bag 1 can be visually recognized.
Furthermore, the main component of the top sheet 3 is polyethylene (PE), polypropylene (PP), nylon, polyethylene terephthalate (PET), polycarbonate (PC), and various resin materials in consideration of the strength and softness of the moisture retaining bag. It is also possible to use.

The lower surface sheet 4 is a sheet body having excellent breathability and water permeability, and having a certain mechanical strength, and for example, a nonwoven fabric made of cellulosic fibers or aliphatic hydrocarbon fibers, or a polymer material is processed. It is composed of a porous film. The size (pore diameter) of the fiber gap is set to a size that prevents the dried polymer powder 10 from leaking out.
The air permeability and water permeability of the lower surface sheet 4 are imparted to favorably guide the moisture of the absorbed water-absorbing polymer to the soil side.

  Here, the polymer powder 10 is composed mainly of sodium polyacrylate. The average particle diameter of the powder particles is about 100 to 200 μm, and is formed into a spherical shape, an elliptical shape, or a shape similar to them. In addition, sodium polyacrylate is a highly water-absorbing polymer, and carboxylate ions act as hydrophilic groups, exhibiting water absorption that reaches several hundred times the mass of their own weight. After water absorption, the sucked water is gradually released to the surroundings for a certain period of time and exhibits a moderate reversibility. Utilizing this action, the moisturizing bag 1 replenishes the plant body with water and exhibits a moisturizing effect.

As the water-absorbing polymer used for the polymer powder 10, at least one of polyacrylate, polyvinyl alcohol, and polyisopropylamide can be used. It is useful for polyacrylic acid salts such as sodium polyacrylate, for which a countermeasure against decomposition is required.
The moisturizing bag 1 having the above configuration is put into a vat or bucket previously filled with water at the time of use, and the polymer powder 10 is absorbed to form a water-containing gel 10x (FIG. 3). In the state which processed in this way, it mounts in the suitable place of soil. At this time, the upper surface sheet 3 is the upper surface and the lower surface sheet 4 is the lower surface.

In addition, after placing the moisturizing bag 1 in a dry state in a proper position on the soil, it is possible to discharge the water and contain it. However, since the upper surface sheet 3 does not allow water to pass through due to the liquid-tightness as described above, care should be taken so that sufficient water is supplied and the polymer powder 10 is contained from the lower surface sheet 4 side.
FIG. 2 shows a method of cultivating a plant body by applying the moisturizing bag 1 to a potted houseplant. In this use example, a plant species that always requires a moisturized state of the soil and that is required to grow in a place directly exposed to sunlight such as a window or a veranda is assumed. Such plants usually need to be watered relatively frequently so that the soil does not dry out while the manager adjusts so that the sun is not insufficient.

A moisturizing effect can be obtained for a certain period by applying a conventional moisturizing bag to such a plant. However, as shown in FIG. 13, in the conventional moisturizing bag, moisture is gradually released from both sides, and moisture in the hydrous gel is lost relatively early. For this reason, even if a moisturizing bag is used, a moisturizing effect cannot be expected continuously.
Furthermore, if the moisture retaining bag continues to be exposed to sunlight, the cross-linked structure of the water-absorbing polymer that has received ultraviolet rays is decomposed and water absorption is impaired. For this reason, the amount of water absorption gradually decreases, and the polymer having a low molecular weight may leak from the bag surface. This problem is prominent when repeatedly using a moisturizing bag, and according to experiments conducted by the inventors, the repeated use twice is the limit.

For such problems, the cultivation method using the moisture retaining bag 1 exhibits the following effects.
As a first effect, the moisturizing bag 1 exhibits a moisturizing effect over a longer period than before. Since the top sheet 3 of the moisturizing bag 1 has airtightness and liquid tightness, moisture does not evaporate from the upper surface of the moisturizing bag 1. Therefore, it is possible to eliminate the water evaporation unnecessary for the moisture retention of the soil, and accordingly, the water sustained release property is efficiently exhibited from the air-permeable lower surface sheet 4 side to the soil (FIG. 3). Thereby, when the moisture retention bag 1 is once absorbed and used, the moisture retention effect by the moisture retention bag 1 can be expected over a long period of time even in a warm place where the sunlight hits.

  As a second effect, the moisture retaining bag 1 can prevent deterioration of the water-absorbing polymer as compared with the prior art, and the moisture retaining bag can be used well over a long period of time. As shown in FIG. 3, in the moisturizing bag 1, ultraviolet rays (VUV, UV, etc.) in sunlight incident from the outside are blocked by the carbon black disposed on the top sheet 3, and the water-containing polymer water-containing gel 10 x is blocked. It is prevented that the crosslinked structure is decomposed. For this reason, the water-containing gel 10x can stably maintain the hydrated form, and continues to release the water gradually. Thereby, the manager can obtain the same moisturizing effect as in the initial use as many times as necessary by absorbing the moisture retaining bag 1 appropriately. In addition, the number of times of water absorption is less than that in the prior art. For this reason, the moisturizing bag 1 of the present invention has a highly useful configuration in cultivation in an environment where it is relatively exposed to sunlight as in the use example of FIG.

In addition, since the upper surface sheet 3 is configured to be black with carbon black, there is also an effect of warming up the soil by accumulating a little when sunlight hits it. Thereby, in the case of growing a plant body that is relatively weak at a low temperature, the same effect as the multi-sheet can be expected.
In addition, depending on the plant species, warm crops that require abundant sunlight, such as citrus fruits including tangerines and lemons, may be cultivated on steep slopes where watering is relatively difficult. The moisturizing bag of the present invention can be directly disposed in such a cropped field, and high utility can be expected by exhibiting a moisturizing effect and ultraviolet durability over a long period of time.

Sodium polyacrylate is also used as a skin moisturizing cosmetic, and at that time, it is also used as a sunscreen cosmetic because of its property of decomposing when it absorbs ultraviolet rays. For this reason, conventionally, there is no technical idea of actively preventing the ultraviolet decomposition of sodium polyacrylate, and the present invention also has a novel effect in this respect.
<Embodiment 2>
In Embodiment 1, although the structure of the moisture retention bag 1 which has a rectangular main surface was illustrated, this invention is not limited to this shape. The main surface shape of the moisturizing bag can be a square shape, other polygonal shapes, a round shape, a donut shape, or the like according to the intended use.

  For example, when applying a moisturizing bag to a flower pot or the like, it may be difficult to use a rectangular moisturizing bag as it is, depending on the type of plant (the bulb is exposed), the planting position, or the size of the flower pot. In this case, as shown in FIG. 4, it is possible to produce a moisturizing bag 1a having a fan-shaped main surface of an appropriate size and arrange it so as to surround the plant in accordance with the soil space. Also in this case, the top sheet 3a is disposed so as to face upward.

Also in the moisturizing bag 1a having the above configuration, the same effect as the moisturizing bag 1 of the first embodiment is exhibited.
<Embodiment 3>
In the moisturizing bag of the present invention, the upper surface and the lower surface sheet can be formed of an integral member. The third embodiment having such a configuration will be described below.

FIG. 5 is a diagram showing a configuration of a moisture retaining bag 1b according to Embodiment 3 of the present invention. FIG. 5A shows an external view, and FIG. 5B shows an assembly diagram.
A feature of the moisture retaining bag 1b is that a belt-shaped exterior sheet 5 made of a non-woven fabric colored with a pigment is bent, and the polymer powder 10 is sandwiched between the inner and outer peripheral portions 50 around the three sides. A size example has a long side of 9.8 cm × a short side of 8.0 cm × a thickness of 3.0 mm, and 0.5 g of the polymer powder 10 is used.

The non-woven fabric forming the exterior sheet 5 has the same configuration as that of the lower sheet 4 and is colored with a brown pigment here. The color to be colored is not limited, but a relatively dark color such as black, amber, green, etc. is preferable in addition to brown. The coloring method may be dyed with a dye or may be applied to the outer surface of a nonwoven fabric.
This moisturizing bag 1b realizes the moisturizing bag with the simpler configuration and the ultraviolet ray countermeasure of the present invention when moisture evaporation from the upper surface not in contact with the soil does not matter so much.

  That is, when the moisture retaining bag 1b is used, the polymer powder 10 is absorbed by pre-immersing the moisture retaining bag in water or discharging water from above. And this is arrange | positioned in the appropriate place of the soil surface. Thereby, the water-containing gel 10x in the moisturizing bag 1b gradually releases moisture from both sides of the moisturizing bag 1b. Due to this action, a good moisturizing effect is exerted over time on the stems, branches, leaves, etc. of the plant located on the upper surface side of the soil and the moisturizing bag.

Further, in the moisturizing bag 1b, the colored nonwoven fabric blocks ultraviolet rays in the sunlight, so that the moisture retaining bag 1b has high water absorption even when used outdoors exposed to the sunlight as in the first and second embodiments. The cross-linked structure of the molecule can be prevented from being decomposed. Therefore, the stable moisture retention characteristic by the favorable water-containing gel 10x can be obtained repeatedly.
In the moisturizing bag 1b, the entire outer sheet 5 is integrally formed of the same material as that of the lower surface sheet 4, so that it is not necessary to prepare the upper surface sheet 3 separately, and the polymer powder 10 can be made relatively simple. It can be configured simply by putting it in an exterior sheet 5 made of a non-woven fabric and sealing it. Therefore, there is an advantage that the present invention can be realized at low cost. Therefore, in addition to being applied to flower pots, it can be applied in large quantities to fields with a relatively large planting area. Moreover, since there is no distinction between the upper and lower surfaces, the arrangement on the soil can be easily performed.

In addition, the structure of the exterior sheet | seat 5 is not limited to a nonwoven fabric, The knitted fabric can also be used.
<Performance measurement experiment>
In order to confirm the actual performance of the moisture retaining bag of the present invention, the following performance measurement experiments were conducted.
(Experiment 1)
For the moisturizing bag of the present invention, an experiment for confirming durability against ultraviolet rays was performed according to the following procedure from the viewpoint of water absorption capability.

As Example 1, a moisturizing bag 1b using the colored nonwoven fabric (white) exterior sheet shown in Embodiment 3 was produced. The size was 4.9 cm long side × 8.0 cm short side × 3.0 mm thickness, and 0.3 g of polymer powder 10 was used.
On the other hand, as Comparative Example 1 having a conventional configuration, a moisturizing bag using a non-colored nonwoven fabric (white) exterior sheet was produced. The size example was 9.8 cm long side × 8.0 cm short side × 3.0 mm thickness, and 0.5 g of polymer powder was used.

In both Example 1 and Comparative Example 1, both sides of the moisture retaining bag are air permeable.
Each of the moisturizing bags prepared above was put into a vat filled with water for about half a day, and the water-absorbing polymer was sufficiently supplied to form a hydrous gel. Then, a plurality of moisture retaining bags after the water absorption treatment were placed on the soil surface of the flower pot in a manner as shown in FIG. 2, and the flower pots were placed near the indoor lighting window. In this state, the weight of each moisturizing bag was measured over time to examine the change in weight. The change in weight was performed in the morning, in the daytime or in the evening, and was investigated for about half a month. Water supply to the dried moisturizing bag was appropriately performed in accordance with the timing when the weight of Comparative Example 1 reached about less than 15%.

  The experimental results are shown in FIG. About Example 1, what converted proportionally the weight so that it was easy to compare with the comparative example 1 was described together. FIG. 7 shows a curve obtained by curve fitting the weight change value immediately after water absorption of Comparative Example 1 in FIG. 6 by a polynomial function (secondary function). 8 to 10 are graphs showing changes in environmental humidity and environmental temperature in the room where the experiment was conducted.

まず、図６に示されるように、比較例１は実施例１に比べ、バッグ重量の減少勾配が大きく、早期に補給が必要なレベルまでに達することが分かった。さらに給水４回目（試験開始から半月）経過後には、比較例１は表１に示すように、給水直後でも当初の給水直後重量の１８％にしかならず、ほとんど吸水させることができなくなった。 In addition, Table 1 shows the measured values of the weight and water absorption of each moisturizing bag during the experiment.

First, as shown in FIG. 6, it was found that Comparative Example 1 had a larger decrease in bag weight than Example 1, and reached a level that required replenishment at an early stage. Further, after the fourth water supply (half month from the start of the test), Comparative Example 1 was only 18% of the weight immediately after the water supply as shown in Table 1, and almost no water could be absorbed.

On the other hand, the change in bag weight in Example 1 (proportional conversion) has a decreasing slope that is clearly smaller than that in Comparative Example 1, and the change in weight until the first water supply in Comparative Example 1 is about half of the initial weight. Is suppressed.
Furthermore, in Comparative Example 1, it can be confirmed that the weight immediately after the water supply decreases every time the water supply operation is repeated (dotted line in FIG. 6, gradient curve in FIG. 7). This is because the cross-linked structure of the water-absorbing polymer was decomposed by ultraviolet rays due to long-term use under sunlight, and the water supply characteristics were impaired. This is considered to be caused by leakage from the gap of the exterior sheet to the outside. As a result of the verification, the number of times that could be practically used in Comparative Example 1 was up to the second time.

  On the other hand, in Example 1, the said problem seen in the comparative example 1 is substantially eliminated. During the experiment, even when the water supply operation is performed four times, the weight immediately after each operation is almost constant (solid line in FIG. 6), and stable performance is maintained. This is considered to be a result of preventing the incidence of ultraviolet rays by the upper surface sheet having a UV cut function and effectively protecting the crosslinked structure of the water-absorbing polymer from decomposition due to ultraviolet irradiation.

The season in which the experiment was conducted was late autumn, the ambient temperature during the experiment was in the range of 18 ° C. to 26 ° C., and the environmental humidity was in the range of 22% to 59% (see FIGS. 8 and 9). reference). However, it is considered that the difference in the characteristics of Example 1 and Comparative Example 1 is not significantly affected by the season even though there are some differences in the number of water supply.
(Experiment 2)
Next, a confirmation experiment was conducted on the sustainability of the moisturizing effect of the moisturizing bag.

As Example 2, a plurality of moisturizing bags 1 shown in Embodiment 1 were produced. The size was (long side 4.9 cm × short side 8.0 cm × thickness 3.0 mm).
A plurality of the moisture retaining bags of Comparative Example 1 described above were prepared. These moisturizing bags were dipped in a vat filled with water to sufficiently form a hydrous gel. Thereafter, the moisturizing bags were placed side by side and placed in the air, and the change in weight due to water evaporation was examined. Each weight change was calculated as an average value of each sample of Example 2 and Comparative Example 1.

The experimental results are shown in FIG.
In FIG. 11, the weight of Comparative Example 1 immediately after water supply is heavier than that of Example 2. This is considered to be caused by the difference in the material characteristics (water absorption, etc.) of the exterior body in addition to the weight variation between the samples subjected to the measurement.
The moisturizing bag weight of Example 2 has followed a very gradual descending line throughout the test period, and is almost stable centering around 150.0 g. This is presumably because moisture was released from the lower surface sheet satisfactorily and excessive release from the upper surface sheet was suppressed and the water content of the water-absorbing polymer was maintained.

On the other hand, the moisture retention bag weight of Comparative Example 1 is drastically reduced as compared with Example 2, and is reduced to about 1/3 of the initial value immediately after the end of the test. Thereby, in the structure of the comparative example 1, water evaporation is active, and it can be confirmed that the structure of the example 2 is suitable for giving priority to the continuous moisturizing effect.
(Experiment 3)
An experiment for confirming the moisturizing effect of the soil in which the moisturizing bag was arranged was performed based on the weight change of the flower pot. As a sample, in addition to Examples 1 and 2, Comparative Example 2 (for comparison with Example 2) using a transparent polyethylene film (ultraviolet transparent film) as an upper sheet and a nonwoven fabric as a lower sheet, and a moisture retaining bag are used. A non-flower pot (Comparative Example 3) was prepared. The pot pot soil (commercial horticultural humus) was all adjusted to the same amount, and each pot was placed in the same position. Then, the weight of each flower pot (the weight excluding the moisturizing bag) was measured before placing the moisturizing bag and when the moisturizing bag was placed for a certain time.

The experimental results are shown in FIG. The weight at the left end indicates the weight of each flower pot immediately before the start of the test.
First, the flower pot of Comparative Example 3 showed a weight reduction of about 80 g on the fourth day after setting. This weight loss is estimated to be due to water evaporation from the flower pot.
The weight loss of Comparative Example 2 was about 45 g under the same conditions. Thus, it was found that when at least a moisturizing bag is used, the amount of water loss can be reduced to about half compared to when not using it.

  On the other hand, in Example 1 in which both the upper surface and the lower surface sheet exhibit air permeability, better water retention is exhibited than in Comparative Example 2 in which the upper surface is formed of an airtight / liquid-tight polyethylene film. This is considered to be a result of stable moisture release by the hydrous gel even though Example 1 has a wider water evaporation area than Comparative Example 2. The reason is considered to be the result that the exterior sheet is colored, the incidence of ultraviolet rays from the outside to the inside of the moisture retaining bag is prevented, and the crosslinked structure of the water-absorbing polymer is well maintained.

  Furthermore, it can be confirmed that the upper surface sheet is airtight / liquid-tight and has a more stable moisture retention than Example 1 in Example 2 which has an ultraviolet blocking effect. This is considered to be a result of suppressing unnecessary moisture evaporation from the top sheet side in addition to the performance of Example 1. Moreover, it can be confirmed that even when a polyethylene film mixed with carbon is used, the UV decomposition of the water-absorbing polymer can be prevented well. Furthermore, in Example 2, by adopting a flexible non-woven fabric and a rigid polyethylene film, the moisture-containing moisture retaining bag is subjected to the stress of “scratching” by the polyethylene film, and the internal moisture is effectively supplied to the soil from the non-woven fabric side. It is also possible that

Although not shown in the figure, when the weight change is continuously followed for Examples 1 and 2, the time point at which the weight values of each other are reversed appears. This indicates that Example 2 has a top sheet made of an airtight / liquid-tight polyethylene film and has particularly good moisture retention characteristics.
From the above experiments, the superiority of the present invention was confirmed.
<Other matters>
In the above embodiment, the configuration using polyacrylate as the water-absorbing polymer is shown, but this is only an example, and other water-absorbing polymers (polyvinyl alcohol (PVA), polyisopropylacrylamide (P- NIPAM) etc. can also be used.

Moreover, the moisturizing bag according to the present invention can be applied to a soil surface of a flower pot, and can also be applied as a multi-sheet in which cocoons are arranged in a cropped field. It can also be used as a substitute for vinyl or non-woven fabric used as a so-called cover for tunnel cropping.
Furthermore, although the polymer powder 10 has exemplified a configuration mainly composed of sodium polyacrylate as a water-absorbing polymer, in the present invention, an ultraviolet decomposition inhibitor (also referred to as an ultraviolet absorber) is separately added to this powder. ) Can also be mixed. Specifically, it is a material that absorbs ultraviolet rays having a wavelength of about 320 nm to 350 nm instead of being easily deteriorated by a water-absorbing polymer, and is preferably at least one of a benzotriazole compound, a benzophenone compound, a salicylate compound, and the like. It is.

  As a commercial product of a benzotriazole-based compound, “Tinubin (registered trademark)” series manufactured by Ciba Geigy Co., Ltd. can be used. As the benzophenone-based compound, 2-hydroxy-4-methoxybenzophenone, 2,2,4,4-tetrahydroxybenzophenone and the like are also suitable. When such an ultraviolet decomposition inhibitor or ultraviolet absorber is used, the crosslinked structure of the water-absorbing polymer can be protected from ultraviolet decomposition by the combination with the top sheet 3 or the exterior sheet 5. In the case of using an ultraviolet decomposition inhibitor or an ultraviolet absorber, there is an advantage that sufficient ultraviolet light countermeasures can be taken against the water-absorbing polymer without separately providing an ultraviolet blocking function to the top sheet or the exterior sheet.

  The horticulture moisturizing bag of the present invention can be used as a means for continuously moisturizing horticultural soil when an ornamental or agricultural crop that is relatively vulnerable to drying is grown under sunlight.

It is a figure which shows the structure of the moisturizing bag for gardening in Embodiment 1 of this invention. It is a figure which shows the example of application of a moisturizing bag. It is sectional drawing for demonstrating the effect of a moisture retention bag. It is a figure which shows the application example of the moisturizing bag for gardening in Embodiment 2. FIG. It is a figure which shows the structure of the moisture retention bag of Embodiment 3. FIG. It is a graph which shows the water supply capability change of the moisture retention bag by ultraviolet rays. It is a graph which shows the water retention capability change by the ultraviolet-ray of a comparative example. It is a graph which shows the humidity change and temperature change of experiment environment. It is a graph which shows the humidity change and temperature change of experiment environment. It is a graph which shows the humidity change and temperature change of experiment environment. It is a graph which shows the weight change of a moisture retention bag. It is a graph which shows the weight change of the flower pot to which a moisture retention bag is applied. It is sectional drawing for demonstrating the problem in the conventional moisture retention bag.

Explanation of symbols

1, 1a, 1b Moisturizing bag 3, 3a Upper surface sheet 4 Lower surface sheet 5 Exterior sheet 10 Polymer powder 10x Polymer powder after water absorption (hydrous gel)
30, 40, 50

Claims (9)

A gardening moisturizing bag in which a water-absorbing polymer-containing material is enclosed in a bag body having air permeability,
At least one surface of the bag is composed of a UV cut sheet that blocks the incidence of ultraviolet rays,
A moisture retaining bag for horticulture, wherein the other surface has moisture permeability. The gardening moisturizing bag according to claim 1, wherein the UV cut sheet has air tightness and liquid tightness. The horticultural moisturizing bag according to claim 1, wherein the UV cut sheet is arranged such that an ultraviolet blocking material is mixed or laminated on a surface of the resin component. The moisture retention bag for horticulture according to claim 3, wherein the ultraviolet blocking material is at least one of carbon, aluminum, and titanium oxide. The gardening moisturizing bag according to claim 1, wherein the UV cut sheet is a colored woven or non-woven fabric. A gardening moisturizing bag in which a water-absorbing polymer-containing material is enclosed in a bag body having air permeability,
The horticultural moisturizing bag, wherein the material contains a decomposition inhibitor for preventing ultraviolet decomposition of the water-absorbing polymer. The gardening moisturizing bag according to claim 6, wherein the decomposition inhibitor is at least one of a benzotriazole compound, a benzophenone compound, a salicylate compound, and the like. The gardening moisturizing bag according to any one of claims 1 to 7, wherein the water-absorbing polymer is at least one of polyacrylate, polyvinyl alcohol, and polyisopropylamide. A method for cultivating a plant, comprising supplying moisture to the plant planted in the soil by placing the moisturizing bag for horticulture according to any one of claims 1 to 8 on the soil.

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