JP2010255346A - Packaging material for water-swelling and water-absorbing resin, bag for sandbag and sandbag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a packaging material from which gel hardly protrudes by an impact and pressure after filling a water-swelling and water-absorbing resin into a bag and swelling the resin with feed water, and a bag for a sandbag and a sandbag using the packaging material. <P>SOLUTION: The packaging material for a water-swelling and water-absorbing resin is formed by superposing a non-woven fabric on a cloth or film and integrating them by needle punching and/or sewing. The fabric or film is formed of a polyolefin resin, and the non-woven fabric is felt. The bag for a sandbag is formed of the packaging material. The sandbag is composed of the bag for a sandbag and the water-swelling and water-absorbing resin. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a water-swellable water-absorbent resin packaging material, a sandbag bag using the same, and a sandbag.

Sandbags are used as a first aid to prevent the invasion of water and earth and sand in the event of floods and water disasters, but in recent years they have been replaced by sandbags consisting of bags filled with earth and sand, and water swelling due to ease of handling and storage Sandbags are used especially in urban areas where water-absorbent water-absorbing resins are packed in water-permeable bags and gelled and swollen by water supply during use. As such, for example, there is a sandbag in which a water-swellable water-absorbent resin is sandwiched between two or more felts and a sheet that is fastened with a needle punch is put in a water-resistant bag (for example, Patent Documents) 1).

JP-A-8-134865

However, there are cases where sandbags are swelled and swollen and then several layers of sandbags are piled up or thrown out. In such a case, the felt and the water-permeable bag may be broken by impact or pressure, and the gel of the water-absorbing resin may protrude. There is a problem that it cannot be used as a sandbag, or it is difficult to handle the gel of the protruding water-absorbent resin. In addition, it is necessary to use a large sheet in which a water-absorbing resin is put in a sandbag, and there is a problem that the operation is troublesome and expensive.
There is a demand for a sandbag that can be formed by a simple method in which a water-absorbent resin is directly placed in a sandbag bag, and that is easy to handle without being broken even when an impact is applied.
An object of the present invention is to provide a packaging material in which a water-swellable water-absorbing resin is put in a bag and swollen by water supply, and then the gel in the gel does not easily protrude even by impact or pressure, and a sandbag and a sandbag using the same. That is.

In view of the above-mentioned problems, the present inventors have conducted intensive research, and as a packaging material for containing a water-swellable water-absorbing resin, the nonwoven fabric is laminated on the fabric or film, and fixed and integrated by needle punching and / or sewing. The present inventors have found that the above-mentioned problems can be solved by using a material, and have reached the present invention.
That is, the invention of claim 1 is a water-swellable water-absorbent resin packaging material in which a nonwoven fabric is laminated on a fabric or a film and fixed and integrated by needle punching and / or sewing.

According to the first aspect of the present invention, a water-swellable water-absorbing resin (hereinafter sometimes simply referred to as a water-absorbing resin) obtained by superimposing a non-woven fabric on a fabric or film and fixing and integrating by needle punching and / or sewing. The packaging material does not pass through the water-absorbent resin gel in the bag made of the packaging material, so the tensile strength is high, so the bag does not tear even under impact or pressure, and the water-absorbent resin gel does not protrude. .

If the nonwoven fabric has a large basis weight, the web of the nonwoven fabric and the gel of the water absorbent resin (hereinafter sometimes simply referred to as gel) are entangled, and it is difficult to pass the gel of the water absorbent resin even under pressure, but the nonwoven fabric has low tensile strength. Pulling or applying an impact may cause the web to slip, creating a gap and producing a gel. On the other hand, the fabric has a relatively high tensile strength. However, when an impact or tension is applied to the fabric, the space between the fibers may spread and the gel in the middle may protrude. A non-woven bag containing a water-absorbent resin put in a sandbag bag made of fabric is a two-layer bag, but when impact or tension is applied, each bag may be torn individually, and the web or fiber Gel may protrude from the gap. However, when needle punching and / or sewing is performed with these two layers overlapped, the nonwoven web is entangled with the fibers of the fabric, or the web or sewing thread penetrates the fabric. Then, since the nonwoven fabric and the fabric are fixed and integrated, the fibers do not shift, and the web of the nonwoven fabric hardly shifts accordingly and the gap does not widen.
That is, the tensile strength of the packaging material of the present invention is substantially increased. Accordingly, the gel in the bag does not break out even under impact or under pressure.

On the other hand, when a nonwoven fabric is piled up using a film instead of a fabric and needle punching and / or sewing is applied, the web or sewing thread of the nonwoven fabric is fixed through the film, so that even if an impact is applied, the web is displaced. The gel in the bag does not stick out. The film does not pass water unless it is perforated, but when the needle punch or the needle of the sewing machine penetrates, the water passes through the gap. As the number of needles per unit area increases, the water absorption tends to increase. That is, even if the film itself does not have water permeability, it has water permeability.
Therefore, the bag of the present invention created using a film instead of the fabric is filled with a water-absorbent resin, and then the bag is brought into contact with water to pass water and the water-absorbent resin swells to contain the gel. Become. The gel containing the gel does not protrude even under impact or pressure.

Of the needle punch and sewing, the needle punch is preferable. Needle punches are economical because they do not require new materials, and there is no risk of thread breakage as in sewing. Further, when the needle punch is applied, the nonwoven web penetrates the fabric and the film and comes out on the opposite side, and becomes crisp, which has an anti-slip effect. For example, when stacked like a sandbag, even if a sandbag bag is created with the fabric surface facing outward and stacked, there is an effect that it is difficult to slip due to injuries. The combination of needle punching and sewing is particularly preferable because the packaging material is more firmly fixed and integrated.
The packaging material of the present invention means a material that wraps the water-absorbent resin, but includes a material that is used as a film or layer that is in contact with the gel of the water-absorbent resin and does not pass through the gel even under impact or pressure.

The invention according to claim 2 is the packaging material according to claim 1, wherein the nonwoven fabric is felt.

According to the invention of claim 2, since the felt is rich in web, it is difficult for the gel to pass through, and the web or sewing thread easily penetrates the fabric or film by needle punching and / or sewing, and the fabric or film It becomes a packaging material in which the nonwoven fabric is firmly integrated.

The invention according to claim 3 is the packaging material according to claim 1 or 2, wherein the fabric or film is formed of a polyolefin-based resin.

According to the invention of claim 3, since the polyolefin resin has heat-fusibility, the nonwoven fabric web and sewing thread are bonded to the polyolefin resin by needle punch and high-speed industrial sewing thread. It becomes an integrated packaging material. Further, since the polyolefin resin is inexpensive, an economical packaging material can be designed.

The invention of claim 4 is a sandbag bag made of the packaging material according to any one of claims 1 to 3.

According to the invention of claim 4, the packaging material in which the nonwoven fabric is firmly bonded to the fabric or film by needle punching or sewing can absorb water and swell the water-absorbing resin therein, and even under pressure and impact. Since the water-absorbent resin gel does not protrude, it can be used for sandbag bags.

The invention according to claim 5 is a sandbag comprising the sandbag bag according to claim 4 and a water-swellable water-absorbent resin.

According to the invention of claim 5, the sandbag bag manufactured using the packaging material in which the nonwoven fabric is firmly bonded to the cloth or film absorbs water when contacted with water and swells the water-absorbing resin therein to form a gel. In addition, the gel of the water-absorbent resin does not protrude even under pressure or impact.

The water-swellable water absorbent resin packaging material of the present invention has the following effects.
(1) After the gel is put in the bag, the gel of the water-absorbent resin does not protrude because it is hard to break even when pressure or impact is applied.
(2) When brought into contact with water, it can absorb water and swell the water-absorbent resin therein.
(3) When used in sandbags, it is lightweight and compact before use and easy to transport and manage. In addition, sandbags in which sandbag bags are made with the fabric or film surface facing outside are not slippery even when stacked.

The perspective view of the packaging material for water-swellable water-absorbent resin of one Embodiment of this invention at the time of applying a needle punch is shown. Sectional drawing in the XY axis | shaft cut surface of the packaging material for water-swellable water absorbing resins in FIG. 1 is shown.

The fabric or film used in the present invention is not limited as long as it has the flexibility to swell in response to the swelling of the water-absorbent resin and can retain the gel. Preferably, it is a water-permeable fabric.
Fabrics include synthetic fibers (polyester, acrylic, polypropylene, polyethylene, polyamide, polyarylate fibers, etc.), semi-synthetic fibers (acetates, rayon, etc.), natural fibers (cotton, silk, wool, etc.), and mixtures of these (blends) All fiber materials can be applied. A woven fabric, a knitted fabric, or a composite fabric knitted with these filament yarns, short fiber spun yarns, and tape yarns composed of them can be used.

It is preferable that the cloth has water permeability so that water can come into contact with the water-absorbent resin. When the bag is formed, it is preferable that it has water absorption. By applying sewing, a nonwoven web or sewing thread penetrates the fabric to form a gap, or a fine hole is generated by a needle. Water permeability comes out by the gaps and holes. However, since the water absorption rate of the fabric increases when the fabric has water permeability, a fabric made of fibers having water absorption and hydrophilicity is preferable. And it is more preferable that the water-absorbent resin is a material having wet strength and flexibility in a wet state so as not to be broken even when the water-absorbing resin swells with water.

Examples of the film used in the present invention include polyester film, nylon film, polyolefin film (polyethylene film, ethylene / α-olefin copolymer film, ethylene / vinyl acetate copolymer film, ethylene / acrylic acid copolymer film, ethylene / acrylic acid ester copolymer film). Synthetic resin films such as polypropylene film; laminated laminate films thereof; metal films such as aluminum foil; and multilayer laminate films of synthetic resin films and metal films. A synthetic resin film and a laminated laminate film thereof are preferable from the viewpoint of flexibility. The thickness is not particularly limited. The film usually does not have water permeability, but it can be used because water permeability comes out when a needle punch is applied. However, a film having fine holes, such as a mesh film (or sheet), is preferable as the film because it has water permeability from the beginning. The size of the hole is 0.1 to 2 mm, more preferably 0.1 to 1 mm. Preferably, the thickness of the film is 30 μm or more because the tensile strength is large and the swelling water-absorbent resin gel can be retained. More preferably, it is 50 μm or more.

In particular, when a polyolefin resin is used as the material of the fabric or film, since the polyolefin resin has heat-sealability, it is more strongly bonded to the nonwoven fabric by needle punching and / or sewing of a high-speed industrial sewing machine and more strongly integrated. A wrapping material can be made. In addition, since the polyolefin resin is inexpensive, an economical packaging material can be designed by using the polyolefin resin.

  As the nonwoven fabric used in the present invention, industrially used nonwoven fabrics can be used. Non-woven fiber materials include synthetic fibers (polyester, polyamide, acrylic, polyolefin fibers, etc.), semi-synthetic fibers (acetate, rayon, etc.), natural fibers (cotton, silk, wool, etc.), carbon fibers, and mixtures thereof. Fiber materials such as blended products can be applied. A nonwoven fabric formed of water-absorbing and hydrophilic fibers is preferable because the packaging material has good water permeability and promotes swelling of the water-absorbing resin inside.

The nonwoven fabric can be used by any method of a dry method and a wet method, and can be produced by any method such as a spunlace method, a thermal bond method, a spunbond method, and a needle punch method. Basis weight of the nonwoven fabric is not particularly limited preferably 30g~800g / m ^2. When it is 30 g / m ² or more, the water-absorbent resin or the gel thereof is entangled with the nonwoven fabric and is difficult to pass. If it is 800 g / m ² or less, the nonwoven fabric does not become too hard and can swell in accordance with the swelling of the water absorbent resin.

Further, a felt obtained by collecting and compressing short fibers or long fibers of the above material in a non-woven fabric is preferable because it has abundant web and is firmly bonded to the fabric or film. Felts are generally called felts such as woven felts, press felts, needle punch felts, etc., and are described in, for example, “Industrial Textile Handbook” (Japan Textile Machinery Society, pages 362 to 381). Can be used.
Basis weight of the felt is not particularly limited, but preferably 30g~500g / m ^2, especially 80~300g / m ² preferred. When it is 30 g / m ² or more, the water-absorbent resin or the gel thereof is entangled with the nonwoven fabric and is difficult to pass. If it is 500 g / m ² or less, the nonwoven fabric does not become too hard and can swell in accordance with the swelling of the water absorbent resin.

The wrapping material of the present invention is obtained by stacking a nonwoven fabric on the above fabric or film and fixing it by needle punching and / or sewing.
The strength of the needle punch is such that the number of needles is preferably 10 / cm ² or more and 200 / cm ² or less, more preferably 30 / cm ² or more and 100 / cm ² or less. If it is 10 / cm ² or more, even if impact or pressure is applied, the bonding of the fabric or film of the packaging material and the nonwoven fabric will not be peeled or broken, and the gel in the bag will not protrude. When the number is 200 / cm ² or less, the packaging material has sufficient flexibility and can swell corresponding to the swelling of the gel. The swelling force of the gel is lost to the force of pressing the needle punch, and water absorption does not occur much.
Sewing is preferably performed with a normal household or industrial sewing machine, and particularly with a high-speed industrial sewing machine. As the sewing thread, cotton, silk or synthetic fibers (polyester, nylon, acrylic, polypropylene, etc.) can be used. The thickness of the sewing thread is changed depending on the application, but the number of threads may be the same as the number of threads in the case of the needle punch.

FIG. 1: shows the perspective view of the packaging material for water-swellable water-absorbent resin of one Embodiment of this invention at the time of applying a needle punch. FIG. 2 shows a cross-sectional view of the water-swellable water-absorbent resin packaging material in FIG. Since the needle punch is applied, the web 3 penetrates the fabric 2 and comes out to the opposite side to form a kava 4, and it can be seen that the nonwoven fabric 1 is fixed to the fabric 2.

The overlap of the fabric or film and the nonwoven fabric may be alternately overlapped and fixed by needle punching and / or sewing, and is preferably 1: 1 to 1: 2. Particularly preferred is 1: 1. When the ratio is 1: 1, the packaging material is thin.
The web itself used for the non-woven fabric is a non-woven fabric itself obtained by applying a needle punch to the fabric or film, and the gel of the water-absorbent resin may protrude under pressure under impact, and is not the packaging material of the present invention. In the present invention, the web itself is not overlapped and subjected to needle punching, but what is once made into a nonwoven fabric is overlapped on a fabric or film and subjected to needle punching and / or sewing. Further, the nonwoven fabric may be stacked in layers and fixed by needle punching and / or sewing. The nonwoven fabric layer is preferably 1 to 3 layers, and more preferably 1 layer from the economical aspect.

The water-swellable water-absorbent resin wrapping material manufactured in this way is substantially more rigid than a single wrapping material in which the fabric or film and the nonwoven fabric are firmly fixed and integrated by needle punching and / or sewing. In addition, the tensile strength is improved and it is difficult to break, and the gel of the water-absorbent resin in the bag does not protrude even under an impact under pressure.

The packaging material of the present invention can be applied to the use of a bag packaging material that is swollen after the water-absorbing resin is added, or the use of a packaging material for a bag into which a pre-swelled gel is placed. It is particularly suitable for applications that require impact resistance and applications that are used under pressure. Examples of uses include sandbag bags, water-stopping material bags, and evaporative cooler bags for neck towels. Moreover, even if it is not a bag, it can be used also as a film | membrane or layer which does not let the gel of a water absorbing resin pass, and what is used for such a use is also included in the range of the packaging material of this invention.

The water-swellable water-absorbing resin used in the packaging material of the present invention is not particularly limited as long as it is insoluble in water and absorbs water and swells, but is inexpensive, safe and durable. It is preferable to have excellent water absorption characteristics such as properties, water absorption magnification and water absorption speed, and no risk of spoilage. As the water-absorbent resin, known resins can be used, such as a polyacrylic acid partially neutralized cross-linked product, a starch-acrylic acid graft polymer neutralized product, a starch-acrylonitrile graft polymer hydrolyzate, and vinyl acetate. -Saponified product of acrylic ester copolymer, isobutylene-maleic anhydride copolymer cross-linked product, hydrolyzate of acrylonitrile copolymer or acrylamide copolymer or cross-linked product thereof, acrylate-acrylamide copolymer cross-linked product, Polyvinyl alcohol cross-linked product, modified polyethylene oxide cross-linked product, acrylamide-2-methylpropane sulfonate copolymer cross-linked product, (meth) acryloylalkane sulfonate copolymer cross-linked product, cross-linked carboxymethyl cellulose salt, cross-linked polymer of cationic monomer Etc. Among these, a crosslinked polyacrylic acid partial neutralized product and a neutralized product of a starch-acrylic acid graft polymer are particularly preferable because they have good water absorption swelling properties, safety and economy.

The water absorption capacity of the water absorbent resin with respect to pure water is preferably 50 to 1,000 ml / g, more preferably 100 to 1,000 ml / g. The shape is not particularly limited, but is preferably powdery or granular. The particle size is preferably 50 to 1500 μm from the viewpoint of water-absorbing swellability, economy, and handleability, and particularly preferably 100 to 850 μm. The water absorption capacity can be measured by a measurement method (gravimetric method) usually used for water absorbent resins.

The amount of the water-absorbing resin in the packaging material is not particularly limited, and the above-described effect of the packaging material can be exhibited if there is a certain amount. The amount of the gel is preferably 1% by weight or more, more preferably 10% by weight or more, particularly preferably 30% by weight or more, and most preferably 50% by weight or more of the content. The larger the amount, the easier it is to confirm the effect of the packaging material. However, if the amount is 1% by weight or more, the above effect of the packaging material can be confirmed.

In addition, when these water-absorbing resins are put in a bag, powdered and / or granular water-absorbing resins may be directly put, but a water-disintegrating or water-soluble sachet (hereinafter referred to as a gelling bag). The bag containing the water-absorbing resin may be put in a gelled material). Water that has entered due to water absorption collapses or dissolves the packaging material of the gelling bag, swells the water-absorbent resin in the gelling bag, breaks the gelling bag, and gels the outer bag. Can be charged with. In this case, if the gelling bag is evenly fixed in the outer bag with a double-sided tape or the like, the water-absorbing resin is not biased even if the outer bag is moved.
The amount of the water-absorbing resin in the gelling bag varies depending on the application, but for example, in the case of sandbag, it is preferably 30 to 70 g / bag.

A sandbag will be described as an example in which the packaging material of the present invention is suitably used.
A sandbag bag is prepared using the packaging material of the present invention, and the production method and usage of the sandbag bag can be performed in the same manner as before.
The sandbag in the present invention is formed by sealing the water-absorbent resin or the gelling material in the sandbag bag as described above. The size of the sandbag is not particularly limited, but when a gelling material is added, there is no particular limitation as long as the size of the bag is equal to or larger than the gelling material, but preferably 20 to 50 cm × 40 to 80 cm, More preferably, it is 25-30 cm x 40-70 cm. The shape of the bag is not limited, but a rectangular shape is preferable from the economical aspect.

The bag can be fixed around the wrapping material of the present invention by a method such as sewing, heat sealing or adhesive. The sandbag bag can be manufactured by forming a bag whose one end is opened and then closing the bag after putting a water-absorbing resin therein. Since the bag needs to be unbreakable even after being swollen with water, one end of the bag is closed by sewing, bonding, or the like, but before closing, a powder or gelling material (preferably 1 -10)). In the case of using a gelling material, it is preferable that the double-sided tape is evenly placed and fixed in the sandbag because the gel fills the sandbag without being biased.

The amount of the water-absorbent resin contained in the sandbag is preferably 0.1 to 5.0% by volume, particularly 0.2 to 2.0%, based on the volume of the sandbag, although it depends on the water absorption capacity. It is more preferable to make the percentage from the relationship between the amount of retained water after the water-absorbing gelation and the shape retention force.

Moreover, you may use another substance together in the range which does not prevent the water absorption ability of a water absorbing resin. Examples of this substance include organic fibers such as pulp, inorganic fibers such as asbestos and pearlite for the purpose of accelerating the water absorption rate, and inorganic substances such as silica sand and stone for the purpose of increasing the specific gravity of the sandbag. Furthermore, you may add a fungicide, a ultraviolet absorber, etc. as needed.

A sandbag made of sandbags with the fabric or film surface facing outside has a feature that it is not slippery even when stacked. This is because the non-woven web penetrates into the fabric or film side by needle punching to form a fluffy shape, and has an anti-slip effect. In addition, sandbags made with the nonwoven fabric side outside have a non-slip effect when stacked from a nonwoven fabric web regardless of needle punching or sewing.
Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited thereto.

Production Example 1 (Creation of gelled material)
10 sheets (a) obtained by laminating a 30 μm-thick poval (PVA) film (Kuraray, CP-1220T10, saponification degree: 87 to 89%) on “Havix JS45HD-W” (manufactured by Habics, dry pulp nonwoven fabric) A bag having a size of 15 cm in size was cut and placed on the PVA film side, and the three ends (sides) were heat-sealed to produce a bag. 50 g of “Sunfresh ST-500D” (acrylic acid-based water-absorbing resin, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was placed therein, and then the opening was heat-sealed (sealed) to produce a gelled material.

Example 1 (Creation of packaging material)
First, a felt was formed into a plate shape with a needle punch such that a nylon / acrylic (7/3) mixed hair had a basis weight of 120 g / m ² and a needle number of 200 / m ² . Next, the above felt is overlapped on a polypropylene plain fabric base fabric (tape fiber: length 14 / inch, width 11 / inch, basis weight: 93 g / m ² ) so that the number of needles is 45 / m ^2. Then, it was fixed with a needle punch to produce a water-swellable water-absorbent resin packaging material A of the present invention.

Example 2 (Creation of packaging material)
The polyester / acrylic (7/3)混毛instead nylon / acrylic (7/3)混毛used in Example 1, the basis weight of the polypropylene plain weave fabric base and 80 g / ^{m 2,} a needle number of the needle punching 45 except that instead of the present / m ² to stitch numbers 90 present / m ² in the same manner as in example 1 to prepare a packaging material B for the water-swellable water-absorbent resin present invention.

Example 3 (Creation of packaging material)
In Example 1, the packaging material C for water-swellable water-absorbent resin of the present invention was used in the same manner as in Example 1 except that a nylon mesh sheet (opening: 200 μm, thickness: 380 μm) was used instead of the polypropylene woven fabric. Created.

Example 4 (Creation of packaging material)
A packaging material D for water-swellable water-absorbent resin according to the present invention was prepared in the same manner as in Example 1 except for the number of needles except that the needle punch was used instead of sewing. Cotton thread was used as the sewing thread.

Examples 5-8, comparative example 1 (creation of sandbags)
A rectangular sandbag having a size of 40 cm × 60 cm was prepared using the water-swellable water-absorbent resin packaging materials A to D of the present invention. First, except for one end, the periphery was sewn and closed tightly, and two gelling materials obtained in Production Example 1 were put from one end and closed by sewing to prepare sandbags A to D of the present invention.
Moreover, a rectangular bag having a size of 40 cm × 60 cm is made of the nylon / acrylic (7/3) mixed non-woven fabric used in Example 1, and two gelling materials obtained in Production Example 1 are put therein. Then, a non-woven cloth sandbag closed by sewing was prepared, and a rectangular outer bag having a size of 40 cm × 60 cm was formed using the polypropylene plain woven base fabric used in Example 1, and the non-woven cloth sand bag was formed. A sandbag E for comparison of double bags was made.
The above sandbags A to D were subjected to a drop test and a gelation test. The results are shown in Table 1.

(1) Swelling test At a temperature of 20 ° C., when 30 L of tap water was filled, the sandbag was put in, and the time until the weight of the sandbag reached 20 kg was measured after water absorption and swelling.
(2) Drop test The sandbag that absorbed 20 kg of water was immediately dropped onto a concrete floor immediately from a height of 1.5 m, and the state of rupture of the bag was observed.

The packaging material of the present invention is suitable for a bag, a film, or a layer that is in contact with the gel of the water-absorbent resin and does not pass the gel even under pressure or impact.

DESCRIPTION OF SYMBOLS 1 Nonwoven fabric 2 Fabric 3 Nonwoven web 4 Keva

Claims (5)

A packaging material for water-swellable water-absorbent resin, wherein a nonwoven fabric is laminated on a fabric or film and fixed by needle punching and / or sewing and integrated. The packaging material according to claim 1, wherein the nonwoven fabric is felt. The packaging material according to claim 1 or 2, wherein the fabric or film is formed of a polyolefin resin. A sandbag bag made of the packaging material according to any one of claims 1 to 3. A sandbag comprising the sandbag bag according to claim 4 and a water-swellable water-absorbent resin.

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