JP6448307B2 - Method for producing water-degradable chemical liquid impregnated sheet - Google Patents

Description

The present invention relates to a method for producing a water-decomposable chemical solution-impregnated sheet used as a wiping cloth or a flush toilet cleaning sheet.

  Chemical solution impregnated sheets are used as wipes and cleaning tools. This chemical-impregnated sheet is broadly classified into non-woven fabric type and paper type depending on the material, but is generally gentle to the skin, soft enough not to scratch the object to be wiped, wiping property free from dirt wiping, and containment In addition to the strength at which the chemical solution impregnated sheet does not break when it is taken out from the container or bag, it is required to have water disintegrability that allows it to flow into a toilet or the like depending on the mode of use.

  Non-woven fabric type fabrics generally use synthetic fibers that are difficult to shorten, so that the fibers can be easily entangled with each other, but the strength is expressed, but the fibers are closely entangled with each other, and the fibers are difficult to unwind and have poor water disintegrability. Therefore, it is not suitable for applications where water disintegration is required. In contrast, paper type paper is generally made of short fiber pulp, and when hydrogen is impregnated with chemicals impregnated with water between the fibers, the hydrogen bonds are easily broken, and the fibers are easy to unwind and have excellent water disintegration. Suitable for applications that require water-disintegration.

  Therefore, a paper type is used for the application of the water-decomposable chemical solution impregnated sheet, but in particular, the wet wipes are required to be soft to touch human skin. As a method of obtaining this softness, a method of imparting softness to a sheet by creping is known. The crepe treatment includes a dry crepe in which a crepe treatment is performed after the wet sheet is dried, and a wet crepe in which a crepe treatment is performed before the wet sheet is dried.

  The conventional example shown in FIG. 8 shows an example of a dry creping process in which a dry crepe is applied by a Yankee dryer 101 to produce a dry sheet 102. This dry crepe has a problem that when it is in a wet state, it swells and the surface irregularities become smooth, making it unsuitable for wiping.

  On the other hand, the dry sheet after the wet crepe treatment is less likely to swell even when wet, and the crepe is retained, so that the wiping property is improved compared to the dry sheet after the dry crepe treatment, but excellent wiping property In order to obtain sufficient wiping properties, for example, a separate process called embossing was required.

  As a technique for embossing a sheet, for example, a technique disclosed in Patent Document 1 is known. In this technique, as shown in FIG. 9, a dry sheet 201 provided with a dry crepe is impregnated with a chemical solution, embossed with an embossing roll 202, and then dried. However, this technique requires two drying steps, a drying process at the time of dry sheet manufacturing and a drying process after embossing, and is economical in terms of low energy efficiency, equipment costs, and running costs. There was a problem that the heavy burden was large.

  As described above, a paper type is suitable for the water-decomposable chemical solution-impregnated sheet, but the paper type has a property that it is low in strength and easily broken because there is no entanglement between fibers. In particular, there was a problem that the sheet was torn when taken out from the slit of the container or bag in a wet state impregnated with a chemical solution.

  On the other hand, in order to give strength to the paper type sheet, mainly from the viewpoint of (1) increasing the basis weight, (2) adding a wet strength improver, or (3) improving the beating degree. Has been developed.

  As a technique from the viewpoint of (1), in addition to a technique for increasing the basis weight with a single layer structure, a technique for increasing the basis weight by using a multilayer structure is known. For example, as shown in FIG. 8, two sheets are stacked, and then dry crepe (creep processing is performed after the wet sheet is dried) is applied with a Yankee dryer 101, thereby increasing the weight of the high-strength dry cloth. Sheet 102 can be manufactured. However, in any case, although the strength is improved, there is a problem that the raw material cost is increased by increasing the basis weight, and there is a problem that the paper quality is stiff, and in addition, the drying property is deteriorated and the energy efficiency is increased. There was a problem in terms of running costs.

  From the viewpoint of (2), for example, the technique disclosed in Patent Document 2 is known. Patent Document 2 describes that a water-soluble polymer is externally added as a wet strength improver to a sheet immediately after being transferred onto a Yankee dryer. According to this technique, although the wet strength of the wet strength improver is improved, there is a problem that when the added amount of the wet strength improver is increased, the water disintegrability is deteriorated and the paper quality is hardened.

  From the viewpoint of (3), the fibers are fluffed by beating and the hydrogen bonds between the fibers are not easily broken, so that the strength is increased. However, it is necessary to provide a refiner facility, and there is a problem that the cost is increased and the paper density is increased. Since it becomes high, there is a problem that the paper quality becomes stiff and the paper quality becomes hard.

  That is, the water-decomposable chemical solution impregnated sheet has softness, wiping property in a wet state, and a high strength in a take-out direction (specific direction) in which a strong force is applied so as not to break even when the sheet is taken out from a container. However, from the viewpoints (1) to (3) described above, it was not possible to satisfy all of the demands.

JP 2009-178572 A JP 2010-150731 A

The present invention has been made in view of such circumstances, and its main purpose is water disintegration, high strength in a specific direction even in a wet state impregnated with a chemical solution, and soft wiping property. It is to provide a method for producing a water-decomposable chemical solution-impregnated sheet excellent in water.

Means for Solving the Problems and Effects of the Invention

  According to the method for producing a water-decomposable chemical solution-impregnated sheet according to the first aspect of the present invention, the wet sheet is formed by laminating raw fibers in a circular net system to form a wet sheet, and the wet sheet forming step. A crepe forming step of forming a crepe on a wet sheet; and a wet sheet on which the crepe is formed by the crepe forming step, sandwiched between a dryer and a touch roll with a canvas interposed between the touch roll and the dryer. A pattern applying step of applying the canvas pattern by pressing, a drying step of drying the wet sheet provided with the pattern by the pattern applying step on the surface of the dryer to form a dry sheet, and the dry sheet A chemical solution impregnation step for impregnating the chemical solution Kill. With the above configuration, when one end of the raw fiber adheres to the circular mesh, the raw fiber adheres to the surface of the circular mesh while being pulled in the rotational direction as the cylinder rotates, so that it is easy to follow the rotational direction (hereinafter referred to as the longitudinal direction). . For this reason, by using a circular mesh system, it is possible to manufacture a water-decomposable chemical solution-impregnated sheet in which raw fibers are oriented in the longitudinal direction. Since more force is required to break the fibers themselves than to separate the fibers, the tensile strength in the longitudinal direction is higher than the tensile strength in the axial direction of the cylinder (hereinafter referred to as the transverse direction). When the wet sheet manufactured as described above is taken out from the container or bag, the wet sheet can be made difficult to break by matching the vertical direction of the wet sheet with the take-out direction. On the other hand, in the wet sheet produced as described above, the raw material fibers oriented in the vertical direction are hydrogen-bonded in the horizontal direction, and water easily enters the gaps between the fibers arranged in the horizontal direction. On the other hand, it is easy to loosen from the lateral direction and can exhibit excellent water disintegration.

  Also, the wet sheet is subjected to a wet crepe process and a canvas pattern imparting process, and then dried with a dryer to form a dry sheet.In contrast to a dry crepe that absorbs moisture and swells, Even if impregnated with a chemical solution, it is difficult to swell and the crepe and canvas pattern are retained, so that the wiping property is excellent.

  Furthermore, because the canvas is structurally water-resistant to the bulky wire that does not have water retention, it can retain a part of the water squeezed by the pressure of the touch roll and the dryer, and dewater the wet sheet. In order to help, it is easy to dry with a dryer and is economical.

  Furthermore, since there is no need for embossing equipment after the dry sheet is formed, two drying steps, ie, the drying process during dry sheet manufacturing and the drying process after embossing, are unnecessary, resulting in high energy efficiency and equipment costs. And it is economical in terms of running costs.

  Furthermore, since the chemical solution is impregnated, a water-decomposable chemical solution-impregnated sheet that can be used for, for example, cleaning of a flush toilet or a wet wipe can be manufactured.

  Moreover, according to the method for producing a water-decomposable chemical solution-impregnated sheet according to the second aspect of the present invention, in the wet sheet forming step, the ratio of the vertical and horizontal tensile strengths (length / width) of the water-decomposable chemical solution-impregnated sheet is 2 It can be configured to control the filtration speed of the raw fiber and the peripheral speed of the circular net in the circular net system so as to be 10 to 10. With the above-described configuration, since the filtration of the raw material through the mesh surface of the circular mesh and the fiber drag effect in the raw material by the rotation of the mesh can be controlled, the ratio of the longitudinal and transverse tensile strengths (vertical / horizontal) is 2 to 10. A water-decomposable chemical solution impregnated sheet can be produced. Therefore, according to the present invention, when the basis weight is the same, it is possible to manufacture a water-decomposable chemical solution-impregnated sheet that is less likely to break in the direction of taking out from a container or bag as compared with the case of making paper by a long net method.

  Furthermore, according to the method for producing a water-decomposable chemical liquid impregnated sheet according to the third aspect of the present invention, in the crepe forming step, the crepe can be formed so that the crepe rate is 3 to 20%. By the said structure, not only wiping off property but a soft and gentle skin-friendly hydrolysable chemical | medical solution impregnation sheet | seat can be manufactured. Here, if the crepe rate is less than 3%, it is not preferable from the viewpoint of softness, surface roughness, wiping properties, and ease of loosening. If the crepe rate exceeds 20%, the tensile strength decreases, so the crepe rate is 3 It is desirable to form the crepe to be ~ 20%.

  Furthermore, according to the method for producing a water-decomposable chemical solution-impregnated sheet according to the fourth aspect of the present invention, in the pattern applying step, the touch pressure of the touch roll is 1.0 to 4.0 kg / cm. it can. With the above configuration, when the touch pressure is less than 1.0 kg / cm, it becomes difficult to apply the canvas pattern to the wet sheet. When the touch pressure exceeds 4.0 kg / cm, the pattern can be applied, but the crepe of the wet sheet can be applied. Since the touch pressure is set to 1.0 to 4.0 kg / cm, a water-decomposable chemical solution-impregnated sheet having both excellent softness and wiping property can be produced.

  Furthermore, according to the method for producing a water-decomposable chemical solution-impregnated sheet according to the fifth aspect of the present invention, in the pattern applying step, the hardness defined by JIS K 6394 of the touch roll is set to 30 ° to 60 °. It can be configured as follows. By the said structure, the hardness of a touch roll shall be 30 degrees-60 degrees, and the water-decomposable chemical | medical solution impregnation sheet | seat which has the outstanding softness and wiping off can be manufactured. Here, although the canvas pattern can be imparted when the hardness of the touch roll exceeds 60 °, the unevenness of the wet crepe is crushed, so that the wiping property by the wet crepe is lowered and the canvas is prematurely deteriorated. . On the other hand, when the hardness of the touch roll is less than 30 °, the deterioration of the canvas is improved, but the canvas pattern cannot be clearly applied and the wiping property is lowered, which is not preferable.

  Furthermore, according to the method for producing a water-decomposable chemical solution impregnated sheet according to the sixth aspect of the present invention, in the chemical solution impregnation step, the chemical solution can contain 5 to 50 wt% of propylene glycol or polyethylene glycol. . With the above configuration, propylene glycol or polyethylene glycol has a cleaning effect, but is not as volatile as ethanol, so a water-degradable chemical liquid-impregnated sheet that is gentle to the skin and excellent in the cleaning effect can be produced. In addition, in the manufacturing process, loss of the chemical solution due to volatilization can be prevented, so that the economy is excellent in terms of running cost. Here, when the content of propylene glycol or polyethylene glycol in the chemical solution is less than 5 wt%, the proportion of water in the chemical solution increases, and therefore mechanical properties such as strength of the water-decomposable chemical solution impregnated sheet decrease. However, even if it exceeds 50 wt%, it is not preferable because water-soluble stains are difficult to wipe off.

  Furthermore, according to the method for producing a water-decomposable chemical solution impregnated sheet according to the seventh aspect of the present invention, in the chemical solution impregnation step, the content of the chemical solution with respect to the dry sheet can be configured to be 100 to 300 wt%. . With the above-described configuration, it is possible to manufacture a water-decomposable chemical solution-impregnated sheet that is soft and excellent in wiping property while maintaining a wet state appropriately so that excessive chemical solution does not drip from the water-degradable chemical solution-impregnated sheet. Here, the raw material fibers vary depending on the type and the degree of beating, but by setting the chemical solution to a content of 300 wt% or less, it is possible to perform a wiping operation without dripping excess chemical solution from the chemical solution impregnated sheet. On the other hand, when the content of the chemical solution is less than 100 wt%, the wettability of the surface of the water-decomposable chemical solution-impregnated sheet is lowered and hardened, and the wiping property is lowered, which is not preferable.

  Furthermore, according to the method for producing a water-decomposable chemical solution-impregnated sheet according to the eighth aspect of the present invention, in the pattern imparting step, the canvas includes a weft and a warp, a plain weave, a double weave, a triple weave, a twill weave. And satin weaving. Due to the above structure, the wet crepe is not crushed between the touch roll and the dryer because of its cushioning properties compared to cotton fiber-based felt. In this respect, a water-decomposable chemical solution impregnated sheet can be produced.

  Furthermore, because of the above configuration, a canvas woven with any one of single weaving, double weaving, triple weaving, twill weaving, or satin weaving is used, so air permeability is better than when felt is used. Therefore, the wet sheet can be easily dried with a dryer, and the manufacturing efficiency and economy are excellent.

  Furthermore, according to the manufacturing method of the water-decomposable chemical solution impregnated sheet according to the ninth aspect of the present invention, a single-tube heating roll can be used as the dryer in the pattern applying step and the drying step. With the above configuration, the thermal efficiency is good and the space of the paper machine can be reduced as compared with the multi-cylinder type.

Furthermore, according to the water-decomposable chemical solution-impregnated sheet according to the tenth aspect of the present invention, the basis weight is 35 to 80 g / m ² , and the looseness as defined in JIS P 4501-1993 is within 100 seconds. Can be configured to With the above-described configuration, a water-decomposable chemical solution-impregnated sheet that is water-degradable, has a high strength in a specific direction even in a wet state impregnated with a chemical solution, and has excellent wiping properties can be provided. Therefore, the water-decomposable chemical solution-impregnated sheet can be taken out from the container or bag without breaking, and the water-decomposable chemical solution-impregnated sheet can be poured into a toilet or the like after wiping work.

  Also, with the above configuration, the water-decomposable chemical solution impregnated sheet can be made into a single layer with a high basis weight, so a low basis weight dry sheet can be laminated in multiple layers with an adhesive or a ply machine prior to chemical solution impregnation. The process of weighting becomes unnecessary, the equipment space can be reduced, and the manufacturing cost can be reduced.

It is the schematic of the circular net papermaking equipment which manufactures a water-decomposable sheet. It is the schematic of the chemical | medical solution impregnation equipment which makes a water-degradable sheet impregnate a chemical | medical solution and manufactures the water-decomposable chemical | medical solution impregnated sheet which concerns on this invention. It is a flowchart which shows the procedure of the manufacturing method of the water-degradable chemical | medical solution impregnation sheet | seat which concerns on this invention. It is a schematic diagram which shows the interwoven structure of the canvas in a circular net papermaking facility. It is a table | surface which shows the manufacturing conditions and paper quality (performance test result) of the water-degradable chemical | medical solution impregnation sheet | seat which concerns on 1st Example-4th Example of this invention, and 1st comparative example-4th comparative example. It is a table | surface which shows the aspect ratio and aspect ratio of the Example of the water-degradable chemical | medical solution impregnation sheet | seat which concerns on one Embodiment of this invention. FIG. 7A is a schematic view when a water-decomposable chemical solution-impregnated sheet is taken out from a box-shaped container, and FIG. 7B is a water-degradable chemical solution-impregnated from a bag-like container. It is a schematic diagram in the case of taking out a sheet. It is a prior art example, and is a schematic diagram of a papermaking facility for producing a water-decomposable sheet having a multilayer structure. It is the prior art, Comprising: It is the schematic of the chemical | medical solution impregnation equipment which manufactures a water-degradable chemical | medical solution impregnation sheet | seat by making a water-degradable sheet impregnate a chemical | medical solution.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below is an example for embodying the technical idea of the present invention, and the present invention is not limited to the following. Further, the present specification by no means specifies the members shown in the claims to the members of the embodiments. In particular, the basis weight, crepe rate, touch pressure, density, softness, surface roughness, wiping rate, ease of loosening, etc. described in the embodiments are within the scope of the present invention unless otherwise specified. It is not intended to limit only to that, but merely an illustrative example. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and symbol indicate the same or the same members, and detailed description thereof will be omitted as appropriate.

(Method for producing water-decomposable chemical solution impregnated sheet)
FIG. 1 and FIG. 2 are schematic views of equipment preferable for carrying out the method for producing a water-decomposable chemical solution-impregnated sheet according to the present invention, and FIG. 1 is an outline of the circular net papermaking equipment X for producing the water-decomposable sheet. FIG. 2 is a schematic view of a chemical liquid impregnation equipment Y for manufacturing a water-degradable chemical liquid-impregnated sheet by impregnating a water-degradable sheet wound in a roll shape with a chemical liquid. Hereinafter, the procedure in the method for producing a water-decomposable chemical solution impregnated sheet according to the present invention will be described based on the flowchart of FIG.

  As shown in FIG. 1, the method for producing a water-decomposable chemical solution-impregnated sheet according to the present invention is prepared by pouring a pulp slurry 1 in which raw fibers and chemicals are dispersed in water into a papermaking tank X2, and dehydrating the pulp slurry 1 from the pulp slurry 1 by a circular net system. Then, step ST1 (corresponding to the wet sheet forming step in the claims) of laminating the raw material fibers on the cylindrical circular net X3 to form the wet sheet 4, and the surface of the circular net X3. Step ST2 of forming a crepe on the wet sheet 4 by picking it up and transferring it to the felt X5, pressurizing and pressing with the press rolls X6 and X7, and peeling off the wet sheet 4 transferred to the surface of the press roll X6 with the blade X8. (Corresponding to the crepe forming step in the claims), the wet roll 4 is transferred to the canvas X9, and the touch roll 10 and the surface of the dryer X11 are sandwiched between the wet sheet 4 on the canvas X9 and pressed by the touch roll X10 to attach the wet sheet 4 to the surface of the dryer X11 and to apply the pattern of the canvas X9 to the wet sheet 4 Step ST3 (corresponding to the pattern applying step in the claims), and step ST4 (drying in the claims) of drying the patterned wet sheet 4 on the surface of the dryer X11 to form the dry sheet 12 Corresponding to the process.) As a main part.

  And the manufacturing method of the water-disintegrating chemical | medical solution impregnation sheet | seat which concerns on this invention winds the dry sheet 12 in roll shape as shown in FIG. 1, forms a dry sheet roll 13, and as shown in FIG. The dry sheet 12 unimpregnated with the chemical solution fed out from the roll 13 is transversely cut for each predetermined length, and the rear part of the downstream cut sheet piece 18 that has already been cut, and the front part of the upstream cut sheet piece 18 And step ST5 (corresponding to the chemical solution impregnation step in the claims) for impregnation by spraying the chemical solution in a superposed state. FIG. 2 illustrates a state in which a mountain fold line and a valley fold line are formed on each cut sheet piece 18 and these cut sheet pieces 18 are sequentially stacked in a Z shape. Hereinafter, each process is explained in full detail.

(First Example)
In step ST1, as shown in FIG. 1, softwood chemical pulp and mercerized pulp are dispersed in water so that the weight ratio becomes softwood chemical pulp / mercelized pulp = 65/35, and then Serogen (registered trademark No. 1) is obtained. Ichi Kogyo Seiyaku Co., Ltd.) and Bindstar (Sanki Co., Ltd.) are each added to 3% of the pulp weight, and the prepared pulp slurry 1 is poured into the papermaking tank X2 of the circular net papermaking facility X.

  Further, in step ST1, the pulp slurry 1 is dehydrated on the surface of the circular net X3 while rotating the cylindrical circular net X3, and raw material fibers are stacked, and the wet sheet 4 is formed on the surface of the circular net X3.

  In step ST2, the wet sheet 4 is transferred from the surface of the circular mesh X3 to the felt X5 as shown in FIG.

  In step ST2, the wet sheet 4 transferred to the felt X5 is pressed and squeezed by the press rolls X6 and X7, and transferred to the surface of the press roll X6.

  Further, in step ST2, the wet sheet 4 transferred to the surface of the press roll X6 is peeled off by the blade X8 to form, for example, a crimped crepe on the wet sheet 4.

In step ST3, as shown in FIG. 1, the wet sheet 4 is moved to the upper part of a net-like canvas X9 (model number NPM60UP manufactured by Nippon Canvas Co., Ltd.). The canvas X9 has an interwoven structure in which wefts and warps made of synthetic resin are interwoven in a double weave so that the contact area ratio is about 10% . Union structure is not limited to the double weave, for example, a flat weave, Mieo, twill, or may be a satin weave.

In step ST3, the wet sheet 4 is pressed together with the canvas X9 by the touch roll X10 having a hardness of 40 ° and the dryer X11 at a touch pressure of 1.5 kg / cm ² . As a result, the wet sheet 4 can be attached to the surface of the dryer X11 and the net pattern of the canvas X9 can be applied to the wet sheet 4 without crushing the crepe.

  In step ST4, as shown in FIG. 1, the wet sheet 4 provided with a pattern is dried on the surface of the dryer X11 to form a dry sheet 12. Here, in FIG. 1, the dry sheet 12 is wound into a roll shape to form a dry sheet roll 13. That is, by forming the dry sheet 12 on the dry sheet roll 13, it is possible to cope with a case where there is a difference in production speed between the circular net papermaking equipment X and the chemical liquid impregnation equipment Y. Note that the circular papermaking equipment X and the chemical liquid impregnation equipment Y may be continued without forming the dry sheet roll 13.

  In step ST5, as shown in FIG. 2, while the dry sheet 12 is fed out from the dry sheet roll 13, the dry sheet 12 is horizontally cut by the cutter roll Y16 every predetermined length.

  Further, in step ST5, water and propylene glycol (by chemical spray Y17 in a state where the downstream cut sheet piece 18 that has already been cut and the front part of the upstream cut sheet piece 18 are overlapped are overlapped. PG) and calcium chloride are mixed at a weight ratio of water / PG / calcium chloride = 57/40/3 and sprayed with the prepared chemical solution. The impregnation amount is 2.5 times the dry weight of the wet sheet 4. Here, in FIG. 2, for example, a fold line and a valley fold line are formed on each cut sheet piece 18 by the folding roll Y19, and these cut sheet pieces 18 are sequentially stacked in a Z shape. That is, by sequentially stacking in a Z shape, it is possible to form a handle for use.

  As described above, the water-decomposable chemical solution-impregnated sheet 14 according to the first embodiment can be manufactured by executing the steps ST1 to ST5.

(Water-decomposable chemical solution impregnated sheet)
In the following second to fourth embodiments, the touch conditions and the crepe rate are changed among the manufacturing conditions described above as the first embodiment, and the same procedure as the first embodiment is avoided in order to avoid duplication. The description of is omitted. As described in detail in the items of performance evaluation, the first to fourth examples have water decomposability, have high strength in a specific direction even in a wet state impregnated with a chemical solution, and have excellent wiping properties. It is an illustration of the water-decomposable chemical solution impregnated sheet 14 evaluated as follows and the manufacturing method thereof.

(Second embodiment)
The water-decomposable chemical solution impregnated sheet 14 according to the second example is obtained in the same manner as in the first example except that the touch pressure is increased at 3.0 kg / cm.

(Third embodiment)
Except for setting the crepe rate to 6.25%, the same procedure as in the first example is performed to obtain the water-decomposable chemical solution-impregnated sheet 14 according to the third example.

(Fourth embodiment)
The water-decomposable chemical solution impregnated sheet 14 according to the fourth embodiment is obtained in the same manner as in the third embodiment except that the touch pressure is increased at 3.0 kg / cm.

(First comparative example)
The following first comparative example to fourth comparative example show comparative examples that serve as the basis for determining that the water-decomposable chemical solution-impregnated sheet 14 of the first to fourth examples is suitable for performance evaluation.

  In the first comparative example, a water-decomposable chemical solution impregnated sheet 14 according to the first comparative example was obtained in the same manner as in the first example except that the crepe rate was 1.0%.

(Second comparative example)
In the second comparative example, a water-decomposable chemical solution-impregnated sheet 14 was obtained in the same manner as in the second example except that the crepe rate was 1.0%.

(Third comparative example)
In the third comparative example, instead of using the net-like canvas X9 at the time of drying, a papermaking felt (model number No. 66-00555ct04251 manufactured by Ichikawa Moori Co., Ltd.) used in a normal papermaking method is used. A water-decomposable chemical solution-impregnated sheet 14 was obtained in the same manner as in the first example except that the papermaking felt X5 was pressed with a touch roll X10 having a hardness of 40 ° and a dryer X11.

(Fourth comparative example)
In the fourth comparative example, a water-decomposable chemical solution impregnated sheet 14 was obtained in the same manner as in the third comparative example except that the touch pressure was increased at 3.0 kg / cm.

(performance test)
The performance test was performed by the method described below.

(Basis weight)
According to JIS P 8124, the weight per unit area of the sheet before adding the cleaning chemical was measured.

  Seal the plastic-added sheet in a plastic bag so that it does not dry, place it in an environment of 23 ° C. and 50% RH for 24 hours or more, then remove the sheet from the plastic bag and immediately test the physical properties other than the basis weight. Went.

(thickness)
The thickness of the sheet was measured using a compression tester (model number KES-65, manufactured by Kato Tech Co., Ltd.) at a pressure of 0.05 kPa.

(density)
From the measured thickness and basis weight, the following formula was used.

Density (g / cm ³ ) = basis weight (g / m ² ) / thickness (mm) × 1000

  Note that the smaller the density value, the larger the bulk.

(soft)
With reference to the method of JAPAN TAPPI No. 34, the following test was performed using a handle ohmmeter (model number No. 226, manufactured by Yasuda Seiki Seisakusho Co., Ltd.). A 10 cm × 10 cm sample sheet was placed on the center of a 20 cm × 20 cm film whose softness was measured in advance, and placed on a 6.35 mm wide slit of the measuring device. The resistance value when the sample was pushed into the slit with the pressure plate of the apparatus was read, and the longitudinal softness of the sheet was calculated by the following formula.

  Sheet softness (mN) = measured value (mN) −film softness (mN)

  In addition, it will become soft, so that a numerical value is small.

(Surface roughness)
The roughness average deviation value (SMD) of the sheet surface was measured using an automated surface tester (model number KESFB4-A-SE manufactured by Kato Tech Co., Ltd.). The contact was made by bending a steel wire having a diameter of 0.2 mm and having a contact length of 5 mm, and the applied pressure was 5 gf. Note that the larger the SMD value, the greater the surface irregularity.

(Wipeability)
In the wiping property test, lipstick stains were used, and evaluation was performed by comparing the wiping rates obtained by the following methods. Apply lipstick (Integrate Gracie (registered trademark) Shiseido Co., Ltd.) on a slide glass (2.5cm x 12.5cm), spread it to 1.3cm x 12cm with a paint brush, etc., and apply as evenly as possible . Overlay the wet sheet on the end of the slide glass coated with lipstick so that the long side of the wet sheet cut into a size of 2.5cm x 10cm and the long side of the slide glass are perpendicular to each other. Pressurization was performed at 2 kPa using a thickness measuring instrument (model number PG-14J, manufactured by Teclock Co., Ltd.).

  Thereafter, to prevent the wet tissue from moving, the part not overlaid on the slide glass was pressed by hand, and the lipstick was wiped out by pulling out the slide glass. The wiping rate was calculated from the following formula by measuring the weight of the applied lipstick and the residual weight of the lipstick after wiping.

  Wiping rate (%) = (1-residual weight of lipstick after wiping / weight of lipstick applied) × 100

  In addition, the wipeability will become high, so that the value of a wiping rate is large.

(Ease of loosening)
In accordance with JIS P 4501, a magnetic stirrer (manufactured by TTP ASONE Co., Ltd.) was used to measure the time for the sheet to loosen in water.

(Tensile strength)
According to JIS P 8113, the strength at which the sheet was broken at a width of 15 mm and an elongation rate of 20 mm / min was measured using a material testing machine (model number RTE1210 manufactured by A & D Corporation).

(Performance evaluation)
The result of the performance evaluation test of the water-decomposable chemical solution impregnated sheet 14 according to the first example to the fourth example and the first comparative example to the fourth comparative example is shown in FIGS.

  First, from FIG. 5, the water-decomposable chemical solution-impregnated sheet 14 according to the first example to the fourth example is (1) bulkier than the water-degradable chemical solution-impregnated sheet 14 according to the first comparative example to the fourth comparative example. , (2) soft, (3) large surface irregularities, and (4) good wiping properties.

  The water-decomposable chemical solution-impregnated sheet 14 according to the first comparative example and the second comparative example is manufactured for the purpose of confirming the effect of the canvas X9 alone, but is low in volume and hard unless creped to some extent in advance. And it was found that there was almost no unevenness.

  In addition, the third comparative example and the fourth comparative example were manufactured by a method using only the crepe in order to confirm the effect of the canvas X9. However, if the canvas X9 is not used, the effect of the crepe is almost lost and the bulk is increased. In addition to being low, hard and almost free of unevenness, it was found that the wiping property was also lowered.

  Further, from the results of the first embodiment, the second embodiment, the third embodiment, and the fourth embodiment, it was found that when the touch pressure is increased, the unevenness is reduced but becomes softer. From this, it was found that which of the wiping property and softness is emphasized can be controlled by the touch pressure.

  Finally, as shown in FIG. 6, it was confirmed that the ratio (vertical / horizontal) of the longitudinal and lateral tensile strengths of the water-decomposable chemical solution impregnated sheet 14 according to the first to fourth examples was 2 or more.

(Usage method of water-decomposable chemical solution impregnated sheet)
In use, as shown in FIGS. 7A and 7B, the user pulls out the water-decomposable chemical solution impregnated sheet 14 stored in the box-shaped container Z15A or the bag-shaped container Z15B from the opening. Since the water-decomposable chemical solution-impregnated sheet 14 has high tensile strength in the vertical direction, the direction in which the water-decomposable chemical solution-impregnated sheet 14 is taken out and the vertical direction of the water-decomposable chemical solution-impregnated sheet 14 are stored so as to match the user. However, when the water-decomposable chemical solution-impregnated sheet 14 is pulled out, the water-decomposable chemical solution-impregnated sheet 14 is not broken. The user disposes in a flush toilet after use.

  As described above, according to the present invention, a water-decomposable chemical solution-impregnated sheet and a water-degradable chemical solution-impregnated sheet that are water-degradable, have a high strength in a specific direction even in a wet state impregnated with a chemical solution, and have excellent wiping properties. A sheet manufacturing method can be provided.

  It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

X ... Circular papermaking equipment X2 ... Papermaking tank X3 ... Circular net X5 ... Felt X6, 7 ... Press roll X8 ... Blade X9 ... Canvas X10 ... Touch roll X11 ... Dryer Y ... Chemical liquid impregnation equipment Y16 ... Cutter roll Y17 ... Chemical liquid spray Y19 ... folding roll 1 ... pulp slurry 4 ... wet sheet 12 ... dry sheet 13 ... dry sheet roll 14 ... hydrolyzable chemical solution impregnated sheet 18 ... cut sheet piece Z15A ... box-shaped container Z15B ... bag-shaped container 101 ... dryers 102, 201 ... Dry sheet 202 ... Embossing roll

Claims (6)

A wet sheet forming step of laminating raw fibers in a circular net system to form a wet sheet;
A crepe forming step of forming a crepe on the wet sheet formed by the wet sheet forming step;
A pattern that imparts a canvas pattern to a wet sheet on which the crepe has been formed by the crepe forming step, sandwiched between a dryer and a touch roll through a canvas, and pressed by the touch roll and the dryer. Granting process;
A drying step of drying the wet sheet provided with the pattern by the pattern applying step on the surface of the dryer to form a dry sheet;
A chemical solution impregnation step of impregnating the dry sheet with the chemical solution,
In the wet sheet forming step, the filtration rate of the raw fiber and the circumferential speed of the circular mesh are set so that the ratio of the vertical and horizontal tensile strengths (vertical / horizontal) of the hydrolyzable chemical solution impregnated sheet is 2 to 10. Control
In the crepe forming step, the crepe is formed so that the crepe rate is 3 to 20%,
In the patterning step, the touch roll, the touch pressure and 1.0~4.0kg / cm, prior Symbol canvas, the weft and warp, a plain weave, a double weave, Mieo, twill and satin A method for producing a water-decomposable chemical solution-impregnated sheet, wherein the sheet is interwoven with any one of the weaving methods. A method for producing a water-decomposable chemical liquid-impregnated sheet according to claim 1,
In the pattern imparting step, the canvas has a weft yarn and a warp yarn interwoven with a double weaving method, and a contact area ratio with the wet sheet on which the crepe is formed in the crepe forming step is 10 %. A method for producing a water-decomposable chemical solution-impregnated sheet. A method for producing the water-decomposable chemical liquid-impregnated sheet according to claim 1 or 2,
The method for producing a water-decomposable chemical solution-impregnated sheet, wherein the water-decomposable chemical solution-impregnated sheet is loaded into a package so as to be pulled out along a longitudinal direction of the water-decomposable chemical solution-impregnated sheet, which is a circular mesh flow direction. . A method for producing a water-decomposable chemical liquid-impregnated sheet according to any one of claims 1 to 3,
In the chemical solution impregnation step, the chemical solution contains 5 to 50 wt% of propylene glycol or polyethylene glycol. A method for producing a water-decomposable chemical liquid-impregnated sheet according to any one of claims 1 to 4,
In the chemical liquid impregnation step, the content ratio of the chemical liquid relative to the dry sheet is 100 to 300 wt%. A method for producing a water-decomposable chemical liquid-impregnated sheet according to any one of claims 1 to 5,
In the said pattern provision process and the said drying process, a single cylinder heating roll is used as said dryer, The manufacturing method of the water-decomposable chemical | medical solution impregnation sheet | seat characterized by the above-mentioned.

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