JP2019017948A - Cleaning sponge - Google Patents

Abstract

To provide a cleaning sponge having proper shape followability.SOLUTION: A cleaning sponge 10 comprises a first layer 12 that is made of a flexible polyurethane foam having cells communicating with one another and in which Asker F hardness is set to be in the range of 40-85 degrees, and a second layer 14 that is made of a porous material having pores communicating with one another and set more flexible than the first layer 12. In the first layer 12, the number of the cells existing on a second surface 12b along a lamination direction of the first and second layers 12 and 14 is set larger than that of the cells existing on a first surface 12a orthogonal to the lamination direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cleaning sponge used for cleaning tableware and cooking utensils.

  As a cleaning sponge used for cleaning tableware and cooking utensils, a multi-layer structure composed of a flexible polyurethane foam and a nonwoven fabric layer attached to one surface of the flexible polyurethane foam has been proposed (for example, patents). Reference 1). In the cleaning sponge, detergent is foamed with a soft polyurethane foam having fine cells, and dishes are washed with a soft flexible polyurethane foam. Further, the cleaning sponge is configured to scrape off dirt stuck to cooking utensils such as a frying pan and a pan with a non-woven fabric layer harder than the flexible polyurethane foam.

JP 2008-99916 A

  In the above-described cleaning sponge, if the nonwoven fabric layer is set so as to be able to scrape hard dirt such as scorch adhered to a frying pan and the like, and the fibers are not hard, the nonwoven fabric layer is difficult to deform. For this reason, the cleaning sponge having a non-woven fabric layer has a difficulty in that it is difficult to squeeze water or the shape following property to a cleaning object such as a frying pan deteriorates.

  The present invention has been proposed in view of the above-described problems related to the prior art, and has been proposed to suitably solve these problems. The cleaning sponge has a layer that is relatively hard and easy to squeeze and has good shape followability. The purpose is to provide.

In order to overcome the above-mentioned problems and achieve the intended purpose, the cleaning sponge of the invention according to claim 1 of the present application comprises:
A first layer made of a flexible polyurethane foam having cells communicating with each other and having an Asker F hardness set in a range of 40 degrees to 85 degrees;
Comprising a porous body having pores communicating with each other, and comprising a second layer set softer than the first layer,
In the first layer, the number of cells existing on the surface along the stacking direction is larger than the number of cells existing on the surface orthogonal to the stacking direction of the first layer and the second layer. This is the gist.
According to the first aspect of the invention, the first layer made of flexible polyurethane foam can be set relatively hard, and even if the first layer is hardened, bending deformation of the first layer is allowed. The shape following property to the object to be cleaned can be improved.

The gist of the invention according to claim 2 is that the first layer is made of a flexible polyurethane foam having a structure in which the cells are removed and the cells communicate with each other.
According to the second aspect of the present invention, the first layer is made of a flexible polyurethane foam having a structure in which the cells are removed and the cells communicate with each other, thereby facilitating drainage of water from the first layer and improving water drainage. Can do.

The gist of the invention according to claim 3 is that the first layer has a number of cells existing in a plane orthogonal to the stacking direction in a range of 7/25 mm to 40/25 mm.
According to the invention which concerns on Claim 3, drainage can be improved by the cell opened comparatively large in a scraping layer.

The gist of the invention according to claim 4 is that the number of cells existing on the surface along the stacking direction of the first layer is in the range of 14 cells / 25 mm to 160 cells / 25 mm.
According to the fourth aspect of the present invention, when the scraping layer is pressed against the object to be cleaned, the scraping layer is difficult to compress and has an appropriate hardness, so that the dirt can be scraped off suitably.

In the invention according to claim 5, wherein the first layer density is summarized in that in the range of ^{60kg / m 3 ~120kg / m 3} .
According to the invention which concerns on Claim 5, it becomes easy to adjust various physical properties, such as the hardness in a 1st layer, water drainage, and the shape followability to a washing | cleaning target object, so that it may become an appropriate balance.

The gist of the invention according to claim 6 is that the first layer is a compression-processed molded product of flexible polyurethane foam, and is arranged so that the compression direction of the compression-processed molded product is the lamination direction. .
According to the sixth aspect of the invention, when the scraping layer is pressed against the object to be cleaned, the scraping layer is difficult to compress and has an appropriate hardness, so that the dirt can be scraped off suitably.

The gist of the invention according to claim 7 is that the first layer is a compression-molded product having a thickness of 1/2 to 1/4 of the original flexible polyurethane foam.
According to the invention which concerns on Claim 7, it becomes easy to adjust various physical properties, such as the hardness in the 1st layer, the water drainage property, and the shape following property to a washing | cleaning target, so that it may become a moderate balance.

The gist of the invention according to claim 8 is that the porous body forming the second layer is a non-compressed molded product of a flexible polyurethane foam having a structure in which the cells as the pores communicate with each other.
According to the invention which concerns on Claim 8, moderate softness which does not damage a washing | cleaning target object is obtained.

  According to the cleaning sponge according to the present invention, the shape followability to the object to be cleaned can be improved even if it has a relatively hard layer.

1 is a schematic perspective view showing a cleaning sponge according to a preferred embodiment of the present invention. It is explanatory drawing which shows the apparatus used for the abrasion resistance test of a scraping layer.

  Next, the cleaning sponge according to the present invention will be described below with reference to the accompanying drawings by way of preferred embodiments. The cleaning sponge according to the present invention can be used for cleaning various objects such as tableware, cooking utensils, washstands, bathrooms, and toilets.

  As shown in FIG. 1, the cleaning sponge 10 according to the embodiment is formed in a cubic shape composed of a rectangular surface. The cleaning sponge 10 is composed of a scraping layer (first layer) 12 made of a flexible polyurethane foam, and a cleaning layer (second layer) that is disposed on the scraping layer 12 and is set to be softer than the scraping layer 12. ) 14. The cleaning sponge 10 has one cleaning surface made up of the scraping layer 12 and the other cleaning surface on the opposite side made up of the cleaning layer 14, and is switched between the scraping layer 12 and the cleaning layer 14 by turning over. Is possible. In the cleaning sponge 10 of the example, the scraping layer 12 is set to be thinner than the cleaning layer 14. For example, when the overall thickness is about 3 cm, the thickness of the scraping layer 12 is about 5 mm. is there.

  The scraping layer 12 is composed of a flexible polyurethane foam having cells communicating with each other. In particular, among flexible polyurethane foams, those having a structure consisting only of a resin skeleton from which the cell membrane is removed by melting or the like to form cells are preferable. By configuring the scraping layer 12 with a soft polyurethane foam having a structure composed only of such a resin skeleton, there is an advantage that water drainage of the scraping layer 12 is improved.

  The scraping layer 12 has an Asker F hardness set in a range of 40 degrees to 85 degrees. If the scraping layer 12 has a hardness in the above range, the dirt attached to the object to be cleaned is scraped off suitably. be able to. If the Asker F hardness is less than 40 degrees, the scraping layer 12 may not be able to obtain a hardness capable of scraping off dirt adhered to the object to be cleaned. If the Asker F hardness is greater than 85 degrees, There is a risk of damaging the object to be cleaned due to its hardness. In addition, it is preferable that the scraping layer 12 sets Asker F hardness to 80 degrees or less. Some conventional sponges made of a nylon nonwoven fabric to which abrasive grains are bonded exceed the scale of Asker F hardness because the abrasive grains are hard. The cleaning sponge 10 of the present invention is set to have a lower hardness of the scraping layer 12 than the above-described conventional nylon nonwoven fabric, so that it is difficult to damage the surface treatment of fluororesin or the like, and the cooking utensil subjected to the surface treatment Suitable for

  The scraping layer 12 is a compression-molded product obtained by uniaxial compression of a flexible polyurethane foam obtained by a predetermined method such as slab foaming, and is harder than the original flexible polyurethane foam by compression molding. The scraping layer 12 is arranged so that the compression direction of the flexible polyurethane foam is the stacking direction of the scraping layer 12 and the cleaning layer 14 in the cleaning sponge 10 (hereinafter simply referred to as the stacking direction). In the scraping layer 12, the number of cells existing per unit length on the second surface 12b along the stacking direction is larger than the number of cells existing per unit length on the first surface 12a orthogonal to the stacking direction. It is increasing. The scraping layer 12 has the same number of cells on the first surface 12a as the original flexible polyurethane foam, whereas the number of cells on the second surface 12b depends on the degree of compression from the original flexible polyurethane foam. And more than the original. Further, the scraping layer 12 has a cell having a larger opening than the second surface 12b on the first surface 12a constituting one of the largest cleaning surfaces in the cleaning sponge 10, and in the cleaning sponge 10 The cell opens smaller than the first surface 12a in the second surface 12b constituting the side surface. In this way, the scraping layer 12 made of a flexible polyurethane foam can be set relatively hard by compression molding, and even if the scraping layer 12 is hard, bending deformation of the scraping layer 12 is allowed. The shape following property of the scraping layer 12 to the object to be cleaned can be improved.

  The scraping layer 12 is preferably set so that the number of cells (conforming to JIS K6400-1) existing on the first surface 12a is in a range of 7 cells / 25 mm to 40 cells / 25 mm. By setting the number of cells of the first surface 12a in the scraping layer 12 within the above range, drainage can be improved by the cells that are relatively open. Further, the scraping layer 12 is preferably set so that the number of cells (conforming to JIS K6400-1) existing on the second surface 12b is in a range of 14 cells / 25 mm to 160 cells / 25 mm. By setting the number of cells of the second surface 12b in the scraping layer 12 within the above range, the scraping layer 12 is compressed in the stacking direction when the first surface 12a serving as the cleaning surface is pressed against the object to be cleaned. Since it is difficult and has an appropriate hardness, dirt can be scraped off suitably. The number of cells does not define only the cells exposed on the surface of the scraping layer 12.

The scraping layer 12 is a compression-molded product having a thickness of 1/2 to 1/4 of the original flexible polyurethane foam, and its density (conforming to JIS K 7222) is 60 kg / m ^{3 to} 120 kg / m. A range of ³ is preferable. Thus, when the density of the scraping layer 12 is in the above range, it becomes easy to adjust various physical properties such as hardness, water drainage, and shape followability to the object to be cleaned so as to have an appropriate balance.

The cleaning layer 14 is made of a porous body having pores communicating with each other, and is set to be softer than the scraping layer 12. Here, as the porous body, an uncompressed molded product of a flexible polyurethane foam having a structure in which cells as pores communicate with each other is suitable. The cleaning layer 14 made of such a non-compressed processed product of flexible polyurethane foam can be provided with appropriate softness that does not damage the object to be cleaned. In the cleaning layer 14, the number of cells existing per unit length on the first surface orthogonal to the stacking direction is the same as the number of cells existing per unit length on the second surface along the stacking direction. The density is lower than that of the scraping layer 12. The cleaning layer 14, for example, the number of cells in the range of (JIS K6400-1 compliant) seven / 25Mm～40 pieces / 25 mm, a density (JIS K 7222-compliant) range of 30kg ^{/ m 3} ~100kg ^/ m 3 Can be used.

  The flexible polyurethane foam used for the scraping layer 12 and the cleaning layer 14 may be either ether-based or ester-based, but is preferably ether-based which has good water resistance and moist heat aging resistance.

  The cleaning sponge 10 can be manufactured as follows, for example. By removing the soft polyurethane foam obtained by slab foaming, etc., the cell membrane is removed, and a plate-like body of a predetermined thickness made of a flexible polyurethane foam having a structure in which the cells communicate with each other is used for the scraping layer. Prepare for each of the cleaning layer. The scraped layer 12 of the compression molded product is obtained by uniaxially compressing the scraped layer plate in the thickness direction while heating. Here, the scraping layer 12 having a compression ratio of 2 to 4 times is formed by compressing the plate-like body for the scraping layer to 1/2 to 1/4 of the original thickness. On the other hand, the plate-like body for the cleaning layer is an uncompressed processed product. By superposing the scraping layer 12 and the plate for cleaning layer so that the compression direction of the scraping layer 12 is the laminating direction, and pressing with a roll coater or the like, a reaction type polyurethane-based hot The cleaning sponge 10 is obtained by laminating with a melt adhesive.

  The cleaning sponge 10 may be provided with unevenness on the cleaning surface of the scraping layer 12 by press working or the like, and appropriate unevenness can be easily formed with a pattern and a pitch derived from such processing. Similarly, unevenness may be provided on the cleaning surface of the cleaning layer 14 by profile processing or the like. Note that the profile processing here refers to a known processing method, for example, a processing method disclosed in JP-A-2006-14819.

(Evaluation of scraped layer)
A scraping layer was prepared under various conditions shown in Table 1 and evaluated for Asker F hardness, frictional force, abrasion resistance, and wiping property. The trade name “CFH-13” of the material in the table indicates a filter foam having a structure in which cells are connected to each other by film removal treatment in an ether-based flexible polyurethane foam (manufactured by INOAC CORPORATION), The number “13” indicates the number of cells. The product name “EPH-20” etc. of the material indicates an ether-based soft polyurethane foam (made by INOAC Corporation) before film removal of the product name “CFH”, and the number “20” after the English letter indicates the number of cells. Show. Comparative Example 1 shown in Table 2 is a scraping layer made of an abrasive-containing nonwoven fabric. Comparative Example 1 is composed of two types of nylon fibers with fineness 22 dtex and single filament fineness 16 dtex, and a material of the nonwoven fiber assembly of fibers basis weight 460 g / m ² (random web). In Comparative Example 1, aluminum hydroxide having an average particle size of 11 μm as an abrasive was adhered to a nonwoven fabric so that the dry solid content would be 800 g / m ² , and the thickness was 32 mm.

  The scraping layer made of the flexible polyurethane foam is obtained by compressing the plate-like body of the flexible polyurethane foam by hot pressing in the thickness direction and compressing it at the compression ratio shown in Table 1. Here, the first surface of the scraping layer is a surface that is orthogonal to the laminating direction with the cleaning layer, and is orthogonal to the compression direction of the flexible polyurethane foam. Moreover, the 2nd surface of a scraping layer is a surface which follows a lamination direction with a washing | cleaning layer, and follows the compression direction of a flexible polyurethane foam. The number of cells and density of the material are standard values of the material manufacturer, and the number of cells on the second surface of the scraping layer and the density of the scraping layer can be calculated from the standard value of the material based on the compression ratio.

  The scraping layer made of the flexible polyurethane foam is subjected to hot pressing using a press plate having a predetermined pattern of holes provided on the first surface serving as the cleaning surface of the cleaning sponge, whereby the pattern derived from the holes Concavities and convexities are formed at a pitch. The “round hole” shown in Table 1 is a press plate (No. 30 manufactured by Taiyo Wire Mesh Co., Ltd., hole diameter 3.0 mm, arranged so that the center of three adjacent round holes (3φ) is an equilateral triangle. The flexible polyurethane foam was hot-pressed using a pitch of 4.0 mm and a perforation ratio of 51.0%, and irregularities with a predetermined pattern were formed on the first surface of the scraped layer obtained. “Square hole” shown in Table 1 is a press plate (No. 188 manufactured by Taiyo Wire Mesh Co., Ltd., hole diameter 3.0 mm, pitch 5.0 mm, hole ratio of 3 mm square holes arranged in a grid pattern at a pitch of 5 mm. 45.0%), the flexible polyurethane foam is hot-pressed to form irregularities with a predetermined pattern on the first surface of the resulting scraping layer. The “round hole + cross hole” shown in Table 1 is a press plate (No. made by Taiyo Wire Mesh Co., Ltd., with a cross hole arranged in the center of four adjacent round holes (3φ) whose centers are arranged in a regular square. 115 and a hole opening ratio of 34.2%), a flexible polyurethane foam is hot-pressed to form a predetermined pattern of irregularities on the first surface of the resulting scraping layer. The “pentagonal hole” shown in Table 1 is a hot press of a flexible polyurethane foam using a press plate arranged so that the center of three adjacent pentagonal holes (size inscribed in a circle of 8 mm) is an equilateral triangle. And the unevenness | corrugation of a predetermined pattern is formed in the 1st surface of the scraping layer obtained.

(Hardness of scraping layer)
For the scraping layer obtained by compressing the material to the thickness shown in Table 1, the hardness of the scraping layer alone was measured. Moreover, also about the scraping layer of the comparative example shown in Table 2, the hardness of the scraping layer alone was measured. As the hardness, Asker F hardness was measured for each scraping layer shown in Table 1 and Comparative Example 1 using an Asker rubber hardness meter F type (manufactured by Kobunshi Keiki Co., Ltd.). Table 2 shows the measurement results of the hardness of each scraping layer.

(Abrasion resistance of scraping layer)
The abrasion resistance of each scraping layer was measured using a Gakushin abrasion tester (manufactured by Daiei Kagaku Seisakusho, trade name: RT-300) 20 as shown in FIG. Specifically, the scraping layer 12 is affixed to the movable base 22 of the Gakushin abrasion tester 20 with a double-sided tape, and the scraping layer 12 is installed on the movable base 22. A sandpaper (product name: LACS-360, AA (aluminum oxide) abrasive grain) 26 as a friction object is pasted to the tip of the pressing rod 24 of the Gakushin abrasion tester 20 with a double-sided tape. Then, the sandpaper 26 is placed in contact with the scraping layer 12 installed on the movable table 22. While applying a constant load (500 g) from the pressing rod 24, the movable table 22 is reciprocated in the horizontal direction at a moving distance of 100 mm and a speed of 30 times / minute until the number of frictions reaches 100 times. Scraped with paper 26. The pre-test weight and post-test weight of the scraping layer were measured, and the wear rate (%) was calculated from the weight change before and after the test. It can be said that the smaller the wear rate of the scraping layer, the better the wear resistance. Table 2 shows the measurement results of the wear resistance of each scraping layer.

(Friction force of scraping layer)
The frictional force of the scraping layer is a kinetic frictional force. Based on the plastic-film and sheet friction coefficient test method specified in JIS K7125, the load cell is 100 N, the specimen size is about 80 × 200 mm, and the sliding piece The contact area was 40 cm ² (length of one side: 63 mm). Table 2 shows the measurement results of the frictional force of each scraping layer.

(Wipeability of scraping layer-flat surface)
The planar wiping property of each scraping layer was evaluated as follows. A polyol (Sanyo Kasei Kogyo Co., Ltd .: GP-3000NS) colored with a blue pigment (phthalocyanine blue pigment) was dropped on an acrylic plastic plate (plate size: 1830 mm × 915 mm) with a commercially available dropoid. Move the scraping layer 800 mm along the plastic plate's plate surface while applying a certain force to the tester in order to clean the tableware such as the cutting board by placing the scraping layer on the polyol dropped onto the plastic plate. The polyol was wiped from the plate surface. The surface wiping property was visually evaluated on the basis of the range and darkness of the polyol streaks remaining on the surface of the plastic plate. Here, on the basis of the scraped layer made of the nonwoven fabric of Comparative Example 1, when the polyol remaining on the plate surface is less than that of Comparative Example 1, it is evaluated as “◯”, and in particular, when the residual polyol is small, it is evaluated as “「 ”. did. Table 2 shows the results of the surface wiping property of each scraping layer.

(Wipeability of scraping layer-curved surface)
The curved surface wiping property of each scraping layer was evaluated as follows. A polyol (Sanyo Kasei Kogyo Co., Ltd.) colored with a blue pigment (blue pigment copper compound phthalate-di-normal butyl dispersion) on a stainless hemispherical ladle (size: diameter φ95 × handle length 280 mm, capacity: 200 cc) (Manufactured by GP-3000NS) was dropped with 30 drops of a commercially available spoid. The above-mentioned scraping layer was brought into contact with the polyol dripped onto the ladle, and the tester of the monitor rotated the scraping layer by 180 ° along the inner surface of the ladle in the manner of normal dishwashing to wipe off the polyol from the ladle. . From the weight difference between before and after wiping off the scraping layer, the wiping amount of polyol is calculated, and based on the scraping layer made of the nonwoven fabric of Comparative Example 1, if the wiping amount is larger than that of Comparative Example 1, “O” In particular, the case where the amount of polyol wiped off was large was evaluated as “評 価”. Table 2 shows the results of the curved surface wiping property of each scraping layer.

  A scraping layer was prepared under various conditions shown in Table 3, and the Asker F hardness, frictional force, wear resistance, and wiping property were evaluated in the same manner as the test described above. The results are shown in Table 3.

  As shown in Tables 2 and 3, the soft polyurethane is compressed in the range of 2 to 4 times the compression ratio, so that a scraping layer having an appropriate hardness that can fit the Asker F hardness in the range of 40 degrees to 85 degrees is obtained. It turns out that it is obtained. Moreover, as shown in Table 1 and Table 3, the scraping layer set to an appropriate hardness by compression molding has the same number of cells on the first surface as the number of cells on the first surface, but the number of cells on the second surface. It can be seen that there are more than the first surface depending on the compression ratio. It can also be seen that the scraping layer set to an appropriate hardness by compression molding has a higher density than the material depending on the compression ratio.

  As shown in Table 2 and Table 3, the scraping layer set to an appropriate hardness by compression molding exhibits wear resistance equivalent to or superior to that of Comparative Example 1 made of a nonwoven fabric, It can be seen that it can withstand scraping applications. Here, it can be seen that the scraping layer tends to have improved hardness and wear resistance as the compression ratio increases.

  As shown in Tables 2 and 3, it can be seen that the scraping layer made of the flexible polyurethane foam has a frictional force twice or more that of Comparative Example 1 made of a nonwoven fabric. That is, according to the scraping layer made of the flexible polyurethane foam, the dirt can be scraped off with a weaker force than the nonwoven fabric, and the object to be cleaned can be prevented from being damaged.

  As shown in Tables 2 and 3, the scraping layer made of a flexible polyurethane foam is superior in the surface wiping property as compared with Comparative Example 1 made of a nonwoven fabric. That is, according to the scraping layer made of the flexible polyurethane foam, the dirt can be removed with a weaker force than the nonwoven fabric, and the dirt can be prevented from returning to the object to be cleaned.

  As shown in Tables 2 and 3, the scraping layer made of the flexible polyurethane foam has excellent curved surface wiping properties as compared with Comparative Example 1 made of a nonwoven fabric. This is because a scraping layer made of a flexible polyurethane foam is superior in shape followability to deform along a curved surface as compared with a nonwoven fabric. And even if the scraping layer made of flexible polyurethane foam is set to the same hardness as the non-woven fabric, it shows a higher surface wiping property than the non-woven fabric, so it is high even if it is hard enough to scrape off dirt. It can be seen that shape followability can be secured.

  According to the above results, the scraped layer made of a compression-molded product of flexible polyurethane foam has both moderate hardness and excellent shape followability to the object to be cleaned. It can be seen that the cleaning performance of the take-up layer is improved. Moreover, according to the scraping layer made of a compression-molded product of a flexible polyurethane foam, it is deformed even if it is hard, so that it is easy to squeeze and grip water.

(Change example)
The present invention is not limited to the configuration described above, and can be modified as follows, for example.
(1) In the embodiment, the cleaning layer has a single layer structure, but the cleaning layer may have a multilayer structure of two or more layers. For example, the intermediate layer that contacts the scraping layer in the cleaning layer may be set so that the detergent foams better in the intermediate layer by making the cells finer and softer than the layer constituting the cleaning surface in the cleaning layer. .
(2) The unevenness provided on the cleaning surface of the scraping layer is not essential, and the cleaning surface may be formed flat.

  12 Scraping layer (first layer), 14 Cleaning layer (second layer)

Claims (8)

A first layer made of a flexible polyurethane foam having cells communicating with each other and having an Asker F hardness set in a range of 40 degrees to 85 degrees;
Comprising a porous body having pores communicating with each other, and comprising a second layer set softer than the first layer,
In the first layer, the number of cells existing on the surface along the stacking direction is larger than the number of cells existing on the surface orthogonal to the stacking direction of the first layer and the second layer. A cleaning sponge characterized by that.   The cleaning sponge according to claim 1, wherein the first layer is made of a flexible polyurethane foam having a structure in which cells are removed and the cells communicate with each other.   The cleaning sponge according to claim 1 or 2, wherein the first layer has a number of cells existing on a plane orthogonal to the stacking direction in a range of 7 / 25mm to 40 / 25mm.   The cleaning sponge according to any one of claims 1 to 3, wherein the first layer has a number of cells existing on a surface along the stacking direction in a range of 14/25 mm to 160/25 mm. . The first layer, cleaning sponge according to any one of claims 1 to 4 having a density in the range of ^{60kg / m 3 ~120kg / m 3} .   The said 1st layer is a compression processing molded product of a flexible polyurethane foam, It arrange | positions so that the compression direction of this compression processing molded product may become the said lamination direction. Cleaning sponge.   The cleaning sponge according to any one of claims 1 to 6, wherein the first layer is a compression-molded product having a thickness of ½ to ¼ of a base flexible polyurethane foam.   The sponge for cleaning according to any one of claims 1 to 7, wherein the porous body forming the second layer is a non-compressed molded product of a flexible polyurethane foam having a structure in which cells as the pores communicate with each other.

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