JP6982515B2 - Liquid coating method and manufacturing method of absorbent articles - Google Patents

Description

The present invention relates to a method of applying a liquid to the surface of an article constituent material used for producing an absorbent article.

Absorbent articles such as disposable diapers and sanitary napkins are typically placed with a surface sheet relatively close to the wearer's skin and relatively far from the wearer's skin. It is composed of a back surface sheet and an absorber interposed between the two sheets. Various liquids such as printing inks for printing patterns, agents for controlling hydrophilicity, skin care agents, antibacterial agents, and fragrances may be applied to the constituent members of such absorbent articles. ..

Patent Document 1 describes a method using flexographic printing as a method for printing a pattern on a base material constituting an absorbent article, for example, a front surface sheet or a back surface sheet. Specifically, it is provided with a central impression cylinder that rotates in the circumferential direction, and a plurality of standard or variable pattern printing stations that are adjacent to the outer peripheral surface of the central impression cylinder and are intermittently arranged in the circumferential direction of the central impression cylinder. It is a method of supplying and transporting a base material on the outer peripheral surface of the central impression cylinder that rotates in the circumferential direction by using an apparatus, and printing a design on the base material by each symbol printing station during the transport. The printing station includes a printing cylinder in which a flexible printing plate is arranged on the outer peripheral surface, and ink supplied from the ink supply unit is deposited on the printing plate via an Anilox roller and transferred to a substrate being transported. It is made to be done. According to the printing method described in Patent Document 1, the print quality and the print speed are improved. Regarding the base material to be printed in the printing method described in Patent Document 1, in [0017] of Patent Document 1, "it is two-dimensional, and its thickness is relatively small (that is, its length and width). It is defined as "material" (1/10 or less), and from this definition and the entire description of Patent Document 1, it is understood that the base material is a sheet-like material having a uniform thickness and a relatively thin thickness.

Patent Documents 2 and 3 describe a compression-deformable porous body containing continuous pores as a method of repeatedly applying a liquid in a predetermined shape pattern having a fixed period to a web continuously conveyed in the production of an absorbent article. Using an application roll in which at least one porous body block formed by the above is arranged discontinuously in the circumferential direction on the outer peripheral surface, the porous body block is impregnated with a liquid, and the porous body block is being conveyed. A method of applying the liquid to the web is described. This porous block is a so-called sponge made of a urethane resin material, and when pressed against the web, it is pushed inward in the radial direction of the application roll and is compressed and deformed. According to the methods described in Patent Documents 2 and 3, it is said that the applied liquid is suppressed from passing through the web, and the degree of impregnation of the liquid in the thickness direction of the web can be controlled.

Special Table 2012-506331A Japanese Unexamined Patent Publication No. 2014-76155 Japanese Unexamined Patent Publication No. 2014-94266

Some of the constituent members of the absorbent article are rich in cushioning properties, those having irregularities on the surface, those having a partially different basis weight, and the like. When a liquid is applied by a so-called contact-type coating method in which the coating device and the object to be coated (constituent members) come into contact with each other as described in Documents 1 to 3, the coating amount should be uniform but non-uniform. In some cases, the surface to be coated with the liquid may be blurred or uneven. For example, even if the surface is a flat surface with no unevenness, when a liquid is applied to the surface of the object to be coated having a partially different basis weight by a contact coating method, the portions having different basis weights are applied to each other. The liquid is not sufficiently applied at the boundary position of the surface, causing blurring and unevenness, and the coating quality deteriorates.

Therefore, an object of the present invention is to provide a liquid coating method and a method for producing an absorbent article, in which the surface to be coated is less likely to be scratched or uneven and good coating quality can be obtained.

In the present invention, a liquid is applied by using a pair of coating rolls in which outer peripheral surfaces are arranged to face each other at predetermined intervals on the surface of an article constituent material used for producing an absorbent article. In the coating method, the article constituent material is supplied between the pair of coating rolls in a state where the liquid is adhered to a coating plate forming one outer peripheral surface of the pair of coating rolls. The coating plate has a coating step of transferring the liquid of the coating plate to the surface of the article constituent material, and the coating plate is non-impregnated with respect to the liquid, and the coating is applied. In the construction process, the article constituent material being conveyed between the pair of coating rolls is temporarily pressed by the pair of coating rolls to be compressed, and the surface of the compressed portion is coated with the coating material. A liquid coating method in which the liquid adhering to the working plate is brought into contact with the article component, and the thickness of the article constituent material after the pressing is released is larger than the thickness at the time of compression by the pressing by the pair of coating rolls. Is.

Further, the present invention is a method for manufacturing an absorbent article having a front surface sheet, a back surface sheet, and an absorber arranged between both sheets, wherein the front surface sheet and the absorber are laminated and laminated. The liquid adheres to the laminating compression step of compressing the laminated body in the thickness direction and the coating plate forming one outer peripheral surface of a pair of coating rolls in which the outer peripheral surfaces are arranged facing each other at a predetermined interval from each other. It has a coating step of transferring the liquid of the coating plate to the surface of the laminate by supplying and transporting the laminate between the pair of coating rolls in the state of being made to be. The coating plate is non-impregnated with respect to the liquid, and in the coating process, the laminated body being conveyed between the pair of coating rolls is temporarily transferred by the pair of coating rolls. While pressing and compressing, the liquid adhering to the coating plate is brought into contact with the surface of the compressed portion, and the laminate is formed from the thickness at the time of compression by pressing by the pair of coating rolls. This is a method for manufacturing an absorbent article, which has a larger thickness after the pressing is released.

According to the present invention, there is provided a liquid coating method and a method for producing an absorbent article, in which the surface to be coated is less likely to be scratched or uneven and good coating quality can be obtained.

FIG. 1 is a perspective view showing a schematic configuration of an embodiment of a liquid coating apparatus that can be used to carry out the liquid coating method of the present invention. FIG. 2 is a diagram showing a main part of the liquid coating apparatus shown in FIG. 1, and is a schematic cross-sectional view taken along the machine direction (transportation direction of the object to be coated) of the main part. FIG. 3 is a schematic front view of the main part of the liquid coating apparatus shown in FIG. 1 when viewed from the machine direction. FIG. 4 is a diagram corresponding to FIG. 3 of another embodiment of the liquid coating apparatus that can be used to carry out the liquid coating method of the present invention. FIG. 5 is a diagram corresponding to FIG. 3 of still another embodiment of the liquid coating apparatus that can be used to carry out the liquid coating method of the present invention. FIG. 6 is a diagram corresponding to FIG. 3 of still another embodiment of the liquid coating apparatus that can be used to carry out the liquid coating method of the present invention.

Hereinafter, the liquid coating method of the present invention will be described with reference to the drawings based on the preferred embodiment thereof. 1 to 3 show a liquid coating device 1 which is an embodiment of a liquid coating device that can be used to carry out the liquid coating method of the present invention. The liquid coating device 1 is a device that applies a liquid (coating liquid) 11 to the surface of an object to be coated 10, and is a pair of coating rolls in which outer peripheral surfaces are arranged facing each other at predetermined intervals. It is composed of a few.

More specifically, the liquid coating apparatus 1 is a coating apparatus adopting a roll transfer method, and as shown in FIGS. 1 to 3, the liquid coating apparatus 1 is arranged in a transport path of the object to be coated 10 and its surface thereof. The coating roll 2 that transfers the liquid 11 to the coating roll 2, the backup roll 3 that is arranged to face the coating roll 2, and the outer peripheral surface (coating plate 21) of the coating roll 2 are arranged in close proximity to the outer peripheral surface. It is configured to include a liquid supply unit 4 for supplying the liquid 11.

The coating roll 2 and the backup roll 3 as a pair of coating rolls each have a cylindrical metal rotating body rotatably supported around a rotation axis. Of the pair of coating rolls 2 and 3, the coating roll 2 is a drive roll that rotates by transmitting a driving force from the driving means to the rotating shaft, and the backup roll 3 is a coating roll 3. It is a roll that rotates with the rotation of the work roll 2.

The coating roll 2 includes a base roll 20 including the rotating body, and a coating plate 21 arranged on the outer peripheral surface of the base roll 20 and forming the outer peripheral surface of the coating roll 2. The liquid 11 supplied from the liquid supply unit 4 is attached to the coating plate 21. In the liquid coating apparatus 1, the coating plate 21 is detachably attached to the outer peripheral surface of the base roll 20. The coating plate 21 may cover the entire outer peripheral surface of the base roll 20 to form the entire outer peripheral surface of the coating roll 2, or may be one of the outer peripheral surfaces of the base roll 20 in the rotation axis direction. Only a part of the outer peripheral surface of the coating roll 2 may be formed by covering only the portion. Further, the coating plate 21 may be continuously extended over the entire length of the coating roll 2 (base roll 20) in the circumferential direction, or may be divided into a plurality of parts in the circumferential direction.

In the liquid coating apparatus 1, the protrusion 23 is partially formed on the surface (outer peripheral surface) of the coating plate 21, so that the surface is provided with irregularities. More specifically, as shown in FIGS. 1 to 3, the coating plate 21 has a standard portion 22 and a protruding portion 23 protruding outward in the radial direction of the coating roll 2 from the standard portion 22. On the surface of the coating plate 21, the protruding portion 23 is formed as a convex portion, and the standard portion 22 is formed as a concave portion (non-formed portion of the protruding portion 23). One protrusion 23 is arranged at the center of the coating roll 2 in the coating plate 21 in the rotation axis direction (CD direction in the drawing), and one protrusion 23 is sandwiched between the protrusions 23 on both sides in the rotation axis direction. The standard part 22 is arranged. On the other hand, the outer peripheral surface of the backup roll 3 is not provided with irregularities and is substantially (macroscopically) smooth.

The coating plate 21 (standard portion 22, projecting portion 23) is non-impregnated with respect to the liquid 11 to be applied to the object to be coated 10. That is, even if the liquid 11 is supplied to the surface of the coating plate 21, the supplied liquid 11 does not permeate the inside of the coating plate 21 and remains attached to the surface. Whether or not the coated plate 21 is non-impregnated is determined by the following method.

<Method of determining non-impregnation property of coated plate>
The surface of the judgment object of the coating plate 21, a liquid 11 to be applied to Hinurikobutsu 10, is deposited droplets using a pipette or the like. At this time, the drop weight (X) of the liquid 11 is 3 g. After 1 minute has passed from the drip, the liquid 11 drip on the surface of the coating plate 21 is removed by wiping with a cloth impregnated with an organic solvent such as ethanol, and the coating after the liquid is removed. The weight (Y1) of the plate 21 is measured, and the liquid residual ratio is calculated by the following formula. “Y0” in the following formula is the weight of the coated plate 21 before the liquid 11 is dropped, and the unit of Y0 is “g” (grams) like X and Y1. “Y1-Y0” in the following formula corresponds to the weight of the liquid 11 that has permeated the inside of the coating plate 21 within 1 minute from the drip.
Liquid residual rate (%) = {(Y1-Y0) / X} x 100
The liquid residual rate is calculated 5 times for each coated plate to be determined, and when the average value of the liquid residual rate for the 5 times is 5% or less, the coated plate is non-impregnated. Is determined.
The type of the organic solvent is determined in consideration of the affinity with the liquid 11 to be coated.

The material of the coating plate 21 is not particularly limited on the premise that it is non-impregnated with respect to the liquid 11, and is typically a metal or a synthetic resin. Further, in the liquid coating apparatus 1, the coating plate 21 has flexibility.

The liquid 11 to be applied to the object to be coated 10 may be any liquid that has fluidity at the temperature at the time of coating and has coating suitability, for example, an adhesive, an oil agent, a skin care effect and a moisturizing effect. Some functional agents and the like can be mentioned. Examples of the adhesive include styrene-based rubber such as styrene / butadiene / styrene block copolymer (SBS), styrene / ethylene / butylene / styrene block copolymer (SEBS), or amorphous poly α-olefin (APAO) and ethylene. Hot melt adhesives such as olefin polymers such as vinyl acetate copolymer (EVA); low density polyethylene, polyvinyl acetate, silicon resin, glue and the like can be mentioned.

The liquid 11 may have a viscosity. The viscosity of the liquid 11 is preferably 0.001 Pa · s or more, more preferably 0.01 Pa · s or more, and preferably 10 Pa · s or less, more preferably 8 Pa · s or less. The viscosity of the liquid 11, a digital viscometer (viscometer TVB-10M (manufactured by Toki Sangyo Co., Ltd.)), the rotor N o. 3, rotation speed: 30 rpm) can be determined using, for example, room temperature (25 ° C.), measured under the conditions of 1 atm.

Further, the object to be coated 10 to which the liquid 11 is applied is an article constituent material used for manufacturing an absorbent article. The term "absorbable article" broadly includes articles used for absorbing body fluids (urine, loose stool, menstrual blood, sweat, etc.) discharged from the human body, and includes, for example, disposable diapers, sanitary napkins, and sanitary napkins. Includes shorts, incontinence pads, etc. Further, the "article constituent material" includes one kind or a combination of two or more kinds of constituent members of the absorbent article, and a manufacturing intermediate of the absorbent article, and the "manufacturing intermediate of the absorbent article" includes the manufacturing intermediate of the absorbent article. , The same as the absorbent article as a finished product is included except that the liquid is not coated.

The object to be coated 10 as an article constituent is, for example, a sheet-like material made of a non-woven fabric, a woven fabric, a resin film, a knitted fabric, or a laminated body in which these sheet-like materials are laminated in two or more layers, or these. It may be an article obtained by laminating or sandwiching another member (for example, an absorber) on a sheet-like material or a laminated body, and specifically, for example, a laminated body including a surface sheet and an absorbent body. .. Further, the object to be coated 10 may be a strip-shaped body continuous in one direction, or may have a predetermined length and may be sequentially conveyed at a predetermined interval.

Further, the object to be coated 10, which is an article constituent material, has a compression recovery property. The "compression recovery" here is a property of trying to return to the original shape when compressed. That is, when an external force is applied to the object to be coated 10 to compress it in the thickness direction and then the external force is removed, the object to be coated 10 tries to return to the original state before compression. Since the object to be coated 10 has such compression recovery property, the features of the liquid coating method of the present invention, which will be described later, are utilized, and the predetermined effect of the present invention is exhibited. That is, in the coating process in the liquid coating method of the present invention described later, the material to be coated, which is an article constituent material, is released from the pressing due to the thickness at the time of compression by pressing by the pair of coating rolls 2 and 3. The thickness after the coating is larger, and the compressive recovery of the object to be coated 10 is one of the factors that influence the manifestation of the predetermined effect of the present invention.

Examples of the object to be coated 10 having compression recovery include those having a “structure having a space inside”, and specifically, for example, a fiber aggregate having voids between fibers, urethane foam, and the like. Sponge can be mentioned. As the fiber aggregate having voids between the fibers, non-woven fabric by various manufacturing methods (air-through non-woven fabric, needle punch non-woven fabric, etc.), non-woven fabric web (web formed by using a card machine), and defibrated hydrophilic material are used. Examples thereof include a laminated fiber body of sex fibers. The entire object to be coated 10 may be a structure having a space inside, or only a part of the object to be coated 10 is the structure, and the rest is another structure such as a resin film. May be good.

From the viewpoint that the object to be coated 10 has an appropriate compression recovery property, the thickness of the object to be coated 10 under no load (the minimum thickness when the thickness is not uniform) is preferably 0.1 mm or more, more preferably 0.1 mm or more. It is 1.0 mm or more, preferably 20 mm or less, and more preferably 10 mm or less. The thickness of the object to be coated 10 is measured by a conventional method using a thickness measuring device (for example, a laser displacement meter manufactured by OMRON Corporation), and is measured at any 10 points of the measurement target site, and the average value thereof is measured. Is the thickness of the object to be coated 10.

From the viewpoint of exerting the predetermined effect of the present invention, the object to be coated 10 preferably has a compression recovery rate of 20% or more, more preferably 30% or more by the KES compression tester. The upper limit is 100%. The compression recovery rate of the object to be coated 10 is specifically measured by the following method according to the KES compression tester.

<Measurement method of compression recovery rate by KES compression tester for the object to be coated>
The object to be coated 10, that is, the article component to be supplied to the liquid coating apparatus 1, is used as a measurement sample, and is attached to a test table on a smooth metal flat surface so that the liquid coating surface side of the measurement sample is the measurement surface. Using a handy compression tester (KES-G5) manufactured by Kato Tech Co., Ltd. as a measuring device, the amount of compression work when the ^{measurement sample is compressed to a maximum load of 6 kgf / cm 2 at a compression rate of 0.02 mm / sec.} The compression recovery rate (%) is calculated by the following formula (1) from (a) and the recovery work amount (b) when the pressure is subsequently removed at the same speed and the load becomes 0.
Compression recovery rate = (b / a) x 100 (%) ... (1)

In order to have the above-mentioned compression recovery rate, the object to be coated 10 as an article constituent material is preferably a surface sheet whose bulk has been restored by heat treatment, or a laminated body containing a surface sheet and an absorber. Preferred embodiments of this laminate will be described in detail later.

As shown in FIG. 1, the object to be coated 10 (article constituent material) of the present embodiment is an absorbent article continuum in which a plurality of absorbent articles such as disposable diapers are connected in one direction, and is an absorbent article. It is composed of a front surface sheet forming a skin facing surface, a back surface sheet forming a non-skin facing surface of an absorbent article, and an absorber interposed between the two sheets. Contains a laminate containing. Here, the "skin facing surface" is a surface of the absorbent article or its constituent members (for example, a surface sheet) that is directed toward the wearer's skin side when the absorbent article is worn, that is, relatively close to the wearer's skin. The "non-skin facing surface" is the surface of the absorbent article or its constituent members that is directed to the side opposite to the skin side (clothing side) when the absorbent article is worn, that is, the wearer's skin relatively. It is on the far side from. In the present embodiment, the liquid 11 is applied to the skin-facing surface, that is, the surface sheet of the object to be coated 10, which is an absorbent article continuum.

Further, as shown in FIGS. 1 and 2, the object to be coated 10 (article constituent material) of the present embodiment has irregularities formed on the surface to be coated of the liquid 11. More specifically, the absorber included in the workpiece 10 of the present embodiment has a standard absorbing portion and a protruding portion having a larger basis weight than the standard absorbing portion, and the protruding portion has a larger basis weight. When the standard absorbing portion protrudes from the skin-facing surface to the surface sheet side (the skin side of the wearer of the absorbent article), the formation position of the protruding portion on the coated surface of the object to be coated 10 is relative. The convex portion 10A having a large basis weight and the thickness, and the other portion on the surface to be coated are concave portions having a relatively small basis weight and the thickness. The convex portion 10A of the object to be coated 10 is also called a so-called middle and high portion, and is located in the inseam portion arranged in the crotch portion of the wearer when worn in the absorbent article, and has a fit of the absorbent article and the like. Contribute to improvement.

When the liquid 11 is applied to the surface of the object to be coated 10 (article constituent material having compression recovery property) having such a configuration by using the liquid coating device 1, as shown in FIGS. 1 to 3. The liquid 11 is supplied from the liquid supply unit 4 to the outer peripheral surface of the coating roll 2 that rotates around the rotation axis, and the liquid 11 adheres to the tip of the protruding portion 23 of the coating plate 21 that forms the outer peripheral surface. In that state, the object to be coated 10 is supplied and conveyed between the pair of coating rolls 2 and 3, and the projecting portion 23 is brought into contact with the object to be coated 10 to bring the liquid in the projecting portion 23 into contact with the liquid. 11 is transferred to the surface of the object to be coated 10 (coating step). In this way, the liquid 11 is coated on the surface of the object to be coated 10, specifically, the surface sheet forming the outermost surface of the laminate including the surface sheet and the absorber. In the figure, the reference numeral MD (Machine Direction) is the machine direction, that is, the transport direction of the object to be coated 10, the reference numeral CD (Cross machine Direction) is the direction orthogonal to the MD, and the CD is each of the rolls 2 and 3. It matches the direction of rotation axis.

However, in such a contact-type coating method, the coating amount of the liquid 11 should be uniform, but the coating amount becomes non-uniform, and the surface to be coated of the liquid 11 in the object to be coated 10 may be blurred or uneven. I am concerned. In particular, in the object to be coated 10 of the present embodiment, as described above, the convex portion 10A is formed on a part of the surface to be coated of the liquid 11, the surface to be coated has unevenness, and the basis weight and the basis weight are The so-called zero-touch coating (coating plate) used in the conventional contact coating method is applied to the object to be coated 10 having a non-uniform basis weight or thickness where the thickness is partially different. When the distance between the object to be coated and the object to be coated is zero, that is, the object to be coated is not pressed by the coating plate and the two are in contact with each other), the tsubo in the object to be coated 10 is tsubo. The liquid 11 may not be sufficiently coated at the boundary portion where the amount or thickness changes, the concave portion of the surface to be coated, or the like, and the surface to be coated may be blurred or uneven.

On the other hand, in the liquid coating method of the present invention, in the coating process, the object to be coated 10 (article constituent material) being conveyed between the pair of coating rolls 2 and 3 is used for the pair of coatings. Since the liquid 11 adhering to the coating plate 21 is brought into contact with the surface of the compressed portion while being temporarily pressed and compressed by the rolls 2 and 3, the object to be coated 10 has compression recovery property. That is, on the premise that "the thickness after the pressing is released is larger than the thickness at the time of compression by the pressing by the pair of coating rolls 2 and 3," there is no unevenness on the surface to be coated. Not only when it is flat and has a uniform basis weight, but also when the basis weight or thickness is not uniform as shown in the figure, the surface to be coated including the recesses is less likely to be scratched or uneven, which is good. Coating quality is obtained.

That is, by temporarily pressing and compressing the object to be coated 10 with the pair of coating rolls 2 and 3, the compressed portion (to the nip portion of both rolls 2 and 3 in the object to be coated 10). Where the (positioned part) is densified and hardened, the reaction force against the pressing force of the pair of coating rolls 2 and 3 acts on the hardened part sufficiently, so that the object to be coated The adhesion between the surface to be coated 10 and the coating plate 21 which is the outer peripheral surface of the coating roll 2 is improved, and the liquid 11 adhering to the coating plate 21 is transferred to the surface to be coated 10. Not only that, it can penetrate into the inside of the object to be coated 10, and as a result, the surface to be coated is less likely to be scratched or uneven, and good coating quality can be obtained. Further, even if the object to be coated 10 has compression recovery property even if it is temporarily compressed by the pair of coating rolls 2 and 3, it passes through the pair of coating rolls 2 and 3. After that, it substantially returns to the original state before compression, and the harmful effects of such temporary compression are unlikely to occur. Further, the liquid coating method of the present invention provides good coating quality by a simple operation of temporarily pressing and compressing the object to be coated 10 with a pair of coating rolls 2 and 3 in the coating process. Therefore, it can be carried out using the existing coating device without causing inconveniences such as complicatedness and large size of the coating device, and the manufacturing efficiency is also excellent.

In addition to the method of temporarily compressing the object to be coated 10 as in the present invention, as a method of preventing the inconvenience that the liquid 11 is faint or uneven on the surface to be coated of the object to be coated 10 is used. A method of adjusting the supply amount of the liquid 11 from the liquid supply unit 4 to the coating plate 21 can be considered. Specifically, for example, by relatively increasing the supply amount of the liquid 11 to the coating plate 21, the amount of the liquid 11 actually applied to the surface to be coated, that is, the coating amount increases, so that the surface to be coated is to be coated. It may be difficult for the work surface to be blurred. However, if the supply amount of the liquid 11 to the coating plate 21 is increased, the variation in the coating amount of the liquid 11 becomes large, so that there is a concern that uneven coating may occur frequently. Further, if the supply amount of the liquid 11 to the coating plate 21 is relatively small in order to suppress the variation in the coating amount of the liquid 11, there is a concern that the surface to be coated may be blurred.

In this respect, in the liquid coating method of the present invention, as described above, the coated plate 21 and the surface to be coated are formed by temporarily compressing the object to be coated 10 from the surface to be coated by the coating plate 21. Since the adhesion of the liquid 11 is improved, even if the amount of the liquid 11 supplied to the coating plate 21 is relatively small, the surface to be coated is less likely to be blurred. Therefore, in implementing the liquid coating method of the present invention, by relatively reducing the supply amount of the liquid 11 to the coating plate 21, the variation in the coating amount of the liquid 11 is further suppressed, and further, the variation in the coating amount of the liquid 11 is further suppressed. The change in the coating amount of the liquid 11 with respect to the change in the interval (clearance) between the pair of coating rolls 2 and 3 can be reduced, and good coating quality can be obtained more stably.

The object to be coated 10 (article constituent material having compression recovery property) to which the liquid coating method of the present invention is particularly useful includes, for example, a laminate of a surface sheet and an absorber, and is applied to a liquid to be coated surface. Those having irregularities, having partially different basis weights, or satisfying both of them can be mentioned. The surface to be coated with the liquid 11 in this case is the surface facing the skin of the surface sheet. The surface sheet may be flat without forming irregularities on the surface facing the skin, or may have irregularities. In the surface sheet having irregularities formed on the surface facing the skin, the convex portions constituting the irregularities may be solid or hollow. Further, as the absorber having a partially different basis weight, in addition to the absorber having a medium-high structure having a convex portion 10A as a so-called middle-high portion as shown in the figure, for example, a skin-facing surface and / or a non-skin facing surface. A block-structured absorber having a groove-like space extending in a plane direction can be mentioned. In the absorber structure of the block structure, for example, a groove-like space is formed in a planar visual grid pattern on the skin facing surface and / or the non-skin facing surface of the absorber, and a plurality of regions partitioned by the grid-like space are formed. , The basis weight is higher than the position where the groove-shaped space is formed. The absorber is composed of a liquid-retaining absorbent core mainly composed of an absorbent material such as pulp fiber or a water-absorbent polymer, and a core wrap sheet that covers the outer surface of the absorbent core. Also, in that case, the basis weight of the absorbent core is usually partially different.

From the viewpoint of ensuring that the action and effect of the temporary compression of the object to be coated 10 by the pair of coating rolls 2 and 3 can be more reliably exerted, the object to be coated 10 is used in the coating process. It is preferable to temporarily compress 60% or more, particularly 65% or more, of the thickness of the object to be coated 10 before pressing. That is, the temporary compression degree of the object to be coated 10 by the pair of coating rolls 2 and 3 in the coating process is preferably 60% or more, more preferably 65% or more.

Further, the compression of the object to be coated 10 by the pair of coating rolls 2 and 3 is temporary for improving the coating quality of the liquid 11, and the influence of such compression on the final product is as much as possible. Less is preferred, ideally zero. From such a viewpoint, the thickness of the object to be coated 10 after the pressing by the pair of coating rolls 2 and 3 is released exceeds 85% of the thickness of the object to be coated 10 before the pressing. It is preferable to compress the coating material 10. In other words, the rate of change in the thickness of the object to be coated 10 due to the pressing of the pair of coating rolls 2 and 3 [= {(thickness of the object to be coated 10 before pressing-of the object to be coated 10 after pressing Thickness) / Thickness of the object to be coated 10 before pressing} × 100] is preferably within 15%, and the object to be coated 10 is preferably compressed.

The degree of compression of the object to be coated 10 by the pair of rolls 2 and 3 for coating can be adjusted by adjusting the distance (clearance) between the rolls 2 and 3 to which the object to be coated 10 is supplied and conveyed. Is. As described above, from the viewpoint of temporarily compressing the workpiece 10 to be coated by 60% or more of its thickness, and making the thickness of the workpiece 10 after compression exceeding 85% of that before compression. The spacing between the pair of coating rolls 2 and 3 is preferably 10% or more, more preferably 15% or more, and preferably 40% or less, more preferably, with respect to the maximum thickness of the object to be coated 10. Is 35% or less. The distance between the pair of coating rolls 2 and 3 is preferably 0.5 mm or more, more preferably 1.0 mm or more, and preferably 5.0 mm or less, more preferably 4.0 mm or less.

Further, the degree of compression of the object to be coated 10 by the pair of coating rolls 2 and 3 is determined by adjusting the distance between the two rolls 2 and 3 as well as the protruding portion of the coating roll 2 in the coating plate 21. It can also be adjusted by devising the pattern of 23. 4 to 6 show coating rolls 2A, 2B, and 2C in which the pattern of the protrusion 23 is devised so that the thickness of the object to be coated 10 after coating can exceed 85% of that before coating. It is shown. Regarding the embodiments shown in FIGS. 4 to 6, components different from the above-described embodiments shown in FIGS. 1 to 3 will be mainly described, and similar components will be designated by the same reference numerals and description thereof will be omitted. The description of the embodiment is appropriately applied to the components not particularly described.

In the coating roll 2A shown in FIG. 4, the protruding portion 23 of the coating plate 21 has a single coating roll 2 (see FIG. 3) in that the coating plate 21 has a plurality of projecting portions 23. different. More specifically, as shown in FIG. 4, in the coating roll 2A, the circumferential direction of the roll 2A (circumferential direction of the coating plate 21) is located at the center of the rotation axis direction (CD) of the coating plate 21. A plurality of (five in this embodiment) annular protrusions 23 that are continuous to each other are intermittently arranged, and in the central portion, the standard portion 22 (concave portion) and the protrusion 23 (convex portion) are arranged in the rotation axis direction. It is arranged alternately on (CD). When the pattern of the protrusions 23 in the coating plate 21 is a pattern in which such a plurality of protrusions 23 are intermittently arranged in the rotation axis direction (CD), a single protrusion 23 is arranged as shown in FIG. Since the compression of the object to be coated 10 is local compared to the non-intermittent arrangement pattern, the thickness of the object to be coated 10 before and after the compression of the object to be coated 10 by the coating plate 21 The change is reduced, and it is possible to minimize the influence of the temporary compression of the object to be coated 10 at the time of coating on the final product.

In the coating roll 2A, the width of each of the plurality of protrusions 23 (the length of the roll 2A in the rotation axis direction) is preferably 0.01 mm or more, more preferably 0.1 mm or more, and preferably 10 mm or less. More preferably, it is 5 mm or less.
In the coating roll 2A, the distance between the protrusions 23 adjacent to each other in the rotation axis direction of the roll 2A is preferably 0.01 mm or more, more preferably 0.1 mm or more, and preferably 15 mm or less, more preferably 5 mm or less. Is.
In the coating roll 2A, the number of protrusions 23 is preferably 3 or more, more preferably 5 or more, and preferably 50 or less, more preferably 30 or less.
Further, "a portion where the liquid 11 is coated by the projecting portion 23 with respect to the entire area of the surface facing the coating roll 2A in the object to be coated 10 (contact with the projecting portion 23 on the surface facing the coating roll 2A). The ratio of the area of the portion) ”, that is, the coating area ratio of the object to be coated 10 is preferably 5% or more, more preferably 10% or more, preferably 50% or less, and more preferably 25% or less.

In the coating roll 2B shown in FIG. 5, the protrusions 23 are formed in a grid pattern on the coating plate 21, and the mesh portion of the grid, that is, the protrusions 23 (convex portions) in a straight line in a plan view forming the grid. The portion surrounded by is a standard portion 22 (recessed portion). The plurality of linear protrusions 23 forming the grid extend in a direction that intersects the rotation axis direction (CD) of the coating plate 21 without being orthogonal to each other. Further, in the coating roll 2C shown in FIG. 6, the coating plate 21 is formed with a plurality of projecting portions 23 having a circular shape in a plan view, and the non-forming portions of the projecting portions 23 are standard portions 22 (recessed portions). ). The coating rolls 2B and 2C also have the same effect as the coating roll 2A. The dimensions and the like of each part of the coating rolls 2B and 2C can be set in the same manner as the coating roll 2A.

Further, in the coating step, it is preferable to heat the liquid 11 and then attach it to the coating plate 21 because the subsequent transfer of the liquid 11 to the object to be coated 10 becomes smooth. The heating of the liquid 11 can be carried out, for example, by heating the liquid 11 with a heating means such as a heater in the liquid supply unit 4. The degree of heating may be appropriately adjusted according to the type of the liquid 11 and the like. Even if the liquid 11 is solid or semi-solid at room temperature (difficult to coat at room temperature), it becomes a liquid by heating and can be transferred to the object to be coated 10. Just do it.

As a preferred embodiment of the object to be coated 10 (composition material having compression recovery property), a laminated body of a surface sheet and an absorber is included, and the surface sheet is subjected to a bulk recovery treatment by heating (a bulk recovery treatment by heating). Hereinafter, a “specific object to be coated”) can be exemplified. The method for manufacturing the specified object to be coated is typically a bulk recovery step in which a surface sheet is heated to perform a bulk recovery treatment, and the surface sheet and the absorber to which the bulk recovery treatment is performed are superposed. It has a stacking compression step of laminating and compressing the laminated body in the thickness direction.

The surface sheet, which is the raw material of the specified object to be coated, is typically a non-woven fabric, and when not in use, it is a raw material wound in the form of a roll. In many cases, the bulkiness of the fabric has been reduced. Therefore, in the method for manufacturing the specified object to be coated, when the bulk recovery step is introduced before the laminated compression step and the surface sheet (nonwoven fabric) is unwound from the roll-shaped raw fabric and used, the surface is used. The reduced bulk is restored by heating the sheet by blowing hot air or steam on the sheet by an air-through method or the like. As the hot air blown to the surface sheet in the bulk recovery step, hot air having a temperature at or near the melting point is usually used with reference to the melting point of the resin component contained in the constituent fibers of the surface sheet. Further, when the bulk of the surface sheet is restored by blowing the hot air of the air-through method, the hot air may be blown from the contact surface side with the absorber in the surface sheet or from the non-contact surface side. As a method for recovering the bulk of the surface sheet (nonwoven fabric) in the bulk recovery step, for example, JP-A-2004-137655, JP-A-2007-177364 and JP-A-2008-231609 according to the previous application of the present applicant. Etc. can be used.

In a typical aspect of the method for manufacturing the specified object to be coated, the surface sheet that has been unwound from the roll-shaped raw fabric and is being conveyed in one direction is subjected to bulk recovery treatment by heating by an air-through method or the like ( Bulk recovery step), the absorbent body is merged with the surface sheet and laminated, and the laminated body of the surface sheet and the absorbent body is compressed in the thickness direction to obtain the specific object to be coated (laminated compression step). By compressing the laminate in this stacking compression step, the laminated state of the surface sheet and the absorber can be stabilized, and typically, the laminate is supplied between a pair of compression rolls and conveyed or laminated. It is carried out by winding the body around a roll while applying tension to the transport direction and transporting the body. The degree of compression of the laminated body in the laminated compression step is a pair of in the coating step, which is carried out on the laminated body (the specific object to be coated) as the object to be coated 10 after the laminated compression step. It is preferably equal to or less than the degree of compression by the coating rolls 2 and 3. That is, the degree of compression performed on the laminated body as the object to be coated 10 (the specific object to be coated) before the coating process is determined by the pair of coating rolls 2 and 2 in the coating process. It is preferably less than or equal to the degree of compression performed on the laminate according to 3. By doing so, the compression recoverability of the object to be coated 10 (the specific object to be coated) is maintained more stably when the object to be coated 10 is subjected to the coating process. Therefore, since the numerical value of the compression recovery rate of the object to be coated 10 by the KES compression tester is high, the above-mentioned "coating during compression by pressing with a pair of coating rolls 2 and 3 in the coating process" is described above. The magnitude relationship of "the thickness of the workpiece 10 to be coated after the pressing is released is larger than the thickness of the workpiece 10" is more reliably realized, and the predetermined effect of the present invention is more reliably achieved. become.

In order to establish the magnitude relationship of "the degree of compression of the laminated body as the object to be coated 10 (the specific object to be coated) in the laminated compression step ≤ the degree of compression of the laminated body in the coating process". In addition, the clearance between the rolls when the laminated body (the laminated body of the surface sheet and the absorber) is supplied and conveyed between the pair of compression rolls in the laminated compression step is the coating performed thereafter. It is preferable that the clearance between the pair of coating rolls 2 and 3 in the construction process is equal to or larger than that. Specifically, the clearance C1 between the pair of compression rolls to which the laminated body to be coated 10 is transported and supplied in the laminated compression step and the coated object 10 to be transported and supplied in the coating process. The ratio of the clearance between the pair of coating rolls 2 and 3 to C2 is preferably 10 or more, more preferably 20 or more, and preferably 90 or less, more preferably C1 / C2, assuming C1 ≧ C2. Is 80 or less.

The present invention includes a method for producing an absorbent article, including a method for producing the specified object to be coated. The method for producing an absorbent article of the present invention includes a process for manufacturing an object to be coated using a surface sheet and an absorber, and a liquid coating step for applying a liquid to the surface of the object to be coated.
In the manufacturing process of the object to be coated, the bulk recovery step of heating the surface sheet to perform the bulk recovery treatment, and the surface sheet subjected to the bulk recovery treatment and the absorber are laminated and laminated. It has a laminate compression step of supplying and transporting a laminate between a pair of compression rolls to compress the laminate in the thickness direction to obtain the object to be coated.
In the liquid coating step, a pair of coating rolls (for example, rolls 2 and 3 in FIG. 1) in which outer peripheral surfaces are arranged facing each other at predetermined intervals are used, and one of the pair of coating rolls is used. (For example, in a state where the liquid is adhered to the coating plate forming the outer peripheral surface of the coating roll 2 in FIG. 1, the object to be coated is supplied and conveyed between the pair of coating rolls. It has a coating step of transferring the liquid of the coating plate to the surface of the object to be coated. The coated plate is non-impregnated with respect to the liquid. In the coating step, the object to be coated being conveyed between the pair of coating rolls is temporarily pressed by the pair of coating rolls to be compressed while being pressed onto the surface of the compressed portion. , The liquid adhering to the coating plate is brought into contact with the liquid.
The thickness of the object to be coated is larger than the thickness at the time of compression by pressing with a pair of coating rolls in the liquid coating process after the pressing is released.
The clearance between the pair of compression rolls is preferably the same as or greater than the clearance between the pair of coating rolls.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and can be appropriately modified. For example, in the liquid coating apparatus 1, the liquid supply unit 4 may have a roll shape in which the liquid is supplied to the coating roll 2 by a transfer method. Further, the following additional notes will be disclosed with respect to the above-described embodiment of the present invention.

<1> A liquid is used by using a pair of coating rolls in which the outer peripheral surfaces are arranged to face each other at predetermined intervals on the surface of the article constituent material (material to be coated) used for manufacturing the absorbent article. It is a liquid coating method that coats
By supplying and transporting the article constituent material between the pair of coating rolls in a state where the liquid is adhered to the coating plate forming one outer peripheral surface of the pair of coating rolls. It has a coating step of transferring the liquid of the coating plate to the surface of the article constituent.
The coated plate is non-impregnated with respect to the liquid and is non-impregnated.
In the coating step, the article constituent material being conveyed between the pair of coating rolls is temporarily pressed by the pair of coating rolls to compress the surface of the compressed portion. The liquid adhering to the coating plate is brought into contact with the liquid.
A liquid coating method in which the thickness of the article constituent material after the pressing is released is larger than the thickness at the time of compression by the pressing by the pair of coating rolls.

<2> The liquid coating method according to <1>, wherein unevenness is formed on the surface to be coated with the liquid in the article constituent material.
<3> The liquid coating method according to <1> or <2>, wherein the article constituent material has a partially different basis weight.
<4> The liquid coating method according to any one of <1> to <3>, wherein in the coating step, the article constituent material is temporarily compressed by 60% or more of the thickness.
<5> The article constituent material is compressed so that the thickness of the article constituent material after the pressing by the pair of coating rolls is released exceeds 85% of the thickness of the article constituent material before the pressing. The liquid coating method according to any one of <1> to <4>.
<6> The liquid coating method according to any one of <1> to <5>, wherein the liquid is heated and then adhered to the coating plate.

<7> The liquid according to any one of <1> to <6>, wherein a protrusion is partially formed on the surface of the coating plate, and the liquid adheres to the tip of the protrusion. Coating method.
<8> The liquid coating method according to <7>, wherein a plurality of protrusions are formed on the surface of the coating plate.
<9> The liquid coating method according to <8>, wherein a plurality of annular protrusions continuous in the circumferential direction of the coating plate are intermittently arranged on the surface of the coating plate.
<10> The width of each of the plurality of protrusions (the length of the coating roll including the coating plate in the rotation axis direction) is preferably 0.01 mm or more, more preferably 0.1 mm or more, and The liquid coating method according to <9>, wherein the liquid coating method is preferably 10 mm or less, more preferably 5 mm or less.
<11> The distance between the protrusions adjacent to each other in the rotation axis direction of the coating roll including the coating plate is preferably 0.01 mm or more, more preferably 0.1 mm or more, and preferably 15 mm or less. The liquid coating method according to <9> or <10>, wherein the liquid coating method is more preferably 5 mm or less.
<12> Any of the above <9> to <11>, wherein the number of the protrusions is preferably 3 or more, more preferably 5 or more, and preferably 50 or less, more preferably 30 or less. The liquid coating method according to item 1.
<13> A portion of the article component to which the liquid is coated by the protrusion (the surface facing the coating roll) with respect to the total area of the surface facing the coating roll including the coating plate in the article constituent material. The ratio of the area of the contact portion with the protrusion), that is, the coating area ratio of the article constituent material (workpiece) is preferably 5% or more, more preferably 10% or more, and preferably 50. The liquid coating method according to any one of <7> to <12> above, which is% or less, more preferably 25% or less.

<14> The viscosity of the liquid is preferably 0.001 Pa · s or more, more preferably 0.01 Pa · s or more, and preferably 10 Pa · s or less, more preferably 8 Pa · s or less. The liquid coating method according to any one of <13>.
<15> The liquid coating method according to any one of <1> to <14>, wherein the article constituent material has compression recovery property.
<16> The thickness of the article constituent material under no load (minimum thickness when the thickness is not uniform) is preferably 0.1 mm or more, more preferably 1.0 mm or more, and preferably 20 mm or less, more preferably. The liquid coating method according to any one of <1> to <15>, wherein is 10 mm or less.
<17> The liquid coating method according to any one of <1> to <16>, wherein the compression recovery rate of the article constituent material is preferably 20% or more, more preferably 30% or more.
<18> In the coating step, the article constituent material is temporarily compressed by preferably 60% or more, more preferably 65% or more of the thickness of the article constituent material, any one of the above <1> to <17>. The liquid coating method according to item 1.
<19> The distance between the pair of coating rolls is preferably 10% or more, more preferably 15% or more, and preferably 40% or less, more preferably 40% or less, based on the maximum thickness of the article constituent. The liquid coating method according to any one of <1> to <18>, which is 35% or less.
<20> The distance between the pair of coating rolls is preferably 0.5 mm or more, more preferably 1.0 mm or more, and preferably 5.0 mm or less, more preferably 4.0 mm or less. 1> The liquid coating method according to any one of <19>.

<21> A method for manufacturing an absorbent article having a front surface sheet, a back surface sheet, and an absorber arranged between both sheets.
A stacking compression step of laminating the surface sheet and the absorber in an overlapping manner and compressing the laminated body (work piece) in the thickness direction.
The laminated body is coated with the pair of coatings in a state where the liquid is adhered to the coating plate forming one outer peripheral surface of the pair of coating rolls in which the outer peripheral surfaces are arranged so as to face each other at a predetermined distance from each other. It has a coating step of transferring the liquid of the coating plate to the surface of the laminate by supplying and transporting the liquid between the rolls.
The coated plate is non-impregnated with respect to the liquid and is non-impregnated.
In the coating step, the laminated body being conveyed between the pair of coating rolls is temporarily pressed by the pair of coating rolls to be compressed, and the surface of the compressed portion is pressed. The liquid adhering to the coating plate is brought into contact with the liquid.
A method for producing an absorbent article, wherein the laminate has a thickness after the pressing is released is larger than the thickness at the time of compression by the pressing by the pair of coating rolls.

<22> It has a bulk recovery step of heating the surface sheet to perform a bulk recovery treatment.
The method for producing an absorbent article according to <21>, wherein in the stacking compression step, the surface sheet subjected to the bulk recovery treatment and the absorber are laminated in layers.
<23> The method for producing an absorbent article according to <22>, wherein in the bulk recovery step, hot air is blown onto the laminate to perform the bulk recovery treatment.
<24> The degree of compression of the laminated body in the laminated compression step is equal to or smaller than the degree of compression by the pair of coating rolls in the coating step, <21> to <23>. The method for producing an absorbent article according to any one of the above items.
<25> In the laminated compression step, the laminated body is supplied between a pair of compression rolls and conveyed to be compressed in the thickness direction.
The absorption according to <24>, wherein the clearance between the pair of compression rolls is the same as or larger than the clearance between the pair of coating rolls to which the laminate is conveyed and supplied in the coating step. Manufacturing method of sex goods.
<26> The method for producing an absorbent article according to any one of <21> to <25>, wherein the surface sheet is made of a non-woven fabric.
<27> Clearance C1 between a pair of compression rolls to which the laminated body is transported and supplied in the laminated compression step, and clearance C2 between a pair of coating rolls to which the laminated body is transported and supplied in the coating process. Assuming that C1 ≧ C2, the ratio of C1 / C2 is preferably 10 or more, more preferably 20 or more, and preferably 90 or less, more preferably 80 or less. > The method for producing an absorbent article according to any one of.

<28> The method for producing an absorbent article according to any one of <21> to <27>, wherein unevenness is formed on the surface to be coated with the liquid in the laminated body.
<29> The method for producing an absorbent article according to any one of <21> to <28>, wherein the laminated body has a partially different basis weight.
<30> The liquid coating method according to any one of <21> to <29>, wherein the laminate is temporarily compressed by 60% or more of the thickness in the coating step.
<31> The laminate is compressed so that the thickness of the laminate after the pressing by the pair of coating rolls is released exceeds 85% of the thickness of the laminate before the pressing. 21> The method for producing an absorbent article according to any one of <30>.
<32> The method for producing an absorbent article according to any one of <21> to <31>, wherein the liquid is heated and then adhered to the coating plate.

<33> The absorption according to any one of <21> to <32>, wherein a protrusion is partially formed on the surface of the coating plate, and the liquid is adhered to the tip of the protrusion. Manufacturing method of sex goods.
<34> The method for producing an absorbent article according to <33>, wherein a plurality of the protrusions are formed on the surface of the coating plate.
<35> The method for producing an absorbent article according to <34>, wherein a plurality of annular protrusions continuous in the circumferential direction of the coating plate are intermittently arranged on the surface of the coating plate.
<36> The width of each of the plurality of protrusions (the length of the coating roll including the coating plate in the rotation axis direction) is preferably 0.01 mm or more, more preferably 0.1 mm or more, and The method for producing an absorbent article according to the above <35>, preferably 10 mm or less, more preferably 5 mm or less.
<37> The distance between the protrusions adjacent to each other in the rotation axis direction of the coating roll including the coating plate is preferably 0.01 mm or more, more preferably 0.1 mm or more, and preferably 15 mm or less. The method for producing an absorbent article according to <35> or <36>, which is more preferably 5 mm or less.
<38> Any of the above <35> to <37>, wherein the number of the protrusions is preferably 3 or more, more preferably 5 or more, and preferably 50 or less, more preferably 30 or less. The method for producing an absorbent article according to item 1.
<39> A portion of the laminated body to which the liquid is coated by the protruding portion with respect to the total area of the surface facing the coating roll including the coating plate (on the surface facing the coating roll). The ratio of the area of the contact portion with the protrusion, that is, the coating area ratio of the laminated body (work piece) is preferably 5% or more, more preferably 10% or more, and preferably 50% or less. The method for producing an absorbent article according to any one of <33> to <38>, which is more preferably 25% or less.

<40> The viscosity of the liquid is preferably 0.001 Pa · s or more, more preferably 0.01 Pa · s or more, and preferably 10 Pa · s or less, more preferably 8 Pa · s or less. > To the method for producing an absorbent article according to any one of <39>.
<41> The method for producing an absorbent article according to any one of <21> to <40>, wherein the laminated body has compression recovery property.
<42> The thickness of the laminate under no load (minimum thickness when the thickness is not uniform) is preferably 0.1 mm or more, more preferably 1.0 mm or more, and preferably 20 mm or less, more preferably. The method for producing an absorbent article according to any one of <21> to <41>, which is 10 mm or less.
<43> The method for producing an absorbent article according to any one of <21> to <42>, wherein the compression recovery rate of the laminate is preferably 20% or more, more preferably 30% or more.
<44> In the coating step, the laminate is temporarily compressed by preferably 60% or more, more preferably 65% or more of the thickness of the laminate, any one of the above <21> to <43>. The method for producing an absorbent article according to the section.
<45> The distance between the pair of coating rolls is preferably 10% or more, more preferably 15% or more, and preferably 40% or less, more preferably 35, with respect to the maximum thickness of the laminate. % Or less, the method for producing an absorbent article according to any one of <21> to <44>.
<46> The distance between the pair of coating rolls is preferably 0.5 mm or more, more preferably 1.0 mm or more, and preferably 5.0 mm or less, more preferably 4.0 mm or less. The method for producing an absorbent article according to any one of <21> to <45>.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to such Examples.

[Example 1]
The liquid 11 was applied to the object to be coated 10 by using the liquid coating apparatus 1 shown in FIGS. 1 to 3. In the coating process of the liquid 11, the object to be coated 10 being conveyed between the pair of coating rolls 2 and 3 is temporarily pressed by the pair of coating rolls 2 and 3 to compress the liquid 11. The liquid 11 adhering to the coating plate 21 was brought into contact with the surface of the compressed portion. Further, in the coating process, the temporary compression degree of the object to be coated 10 is appropriately changed by appropriately changing the interval between the pair of coating rolls 2 and 3. As shown in FIG. 3, in the coating plate 21 used in the first embodiment, the entire area of the contact portion with the object to be coated 10 is a protruding portion 23, and the object to be coated obtained by using this is a protrusion 23. The coating area ratio of 10 was 100%.

In Example 1, a laminate of a surface sheet and an absorber (an article constituent material used for manufacturing an absorbent article) was used as the object to be coated 10. As the surface sheet, a non-woven fabric having a basis weight of 74 g / m ^{2 was used.} As the absorber, an absorbent core having a total basis weight of 470 g / m ² composed of a uniform mixture of fluff pulp 400 g / m ² and a water-absorbent polymer 70 g / m ² and a basis weight 16 g covering the outer surface of the absorbent core. An absorber with a core wrap sheet made of / m ^{2 paper was used.} The workpiece 10 used in Example 1 had a thickness of 5.5 mm under no load and a compression recovery rate of 95% by the KES compression tester. Further, in Example 1, epoxy-modified dimethyl silicone (KF-101, manufactured by Shin-Etsu Chemical Co., Ltd.) was used as the liquid 11 to be coated on the object to be coated 10, and the viscosity of the liquid 11 measured by the above method was measured. It was 0.15 Pa · s.

[Example 2]
The liquid 11 was applied to the object to be coated 10 in the same manner as in Example 1 except that the coating roll 2A (see FIG. 4) was used instead of the coating roll 2 (see FIG. 3). As shown in FIG. 4, the coating plate 21 used in the second embodiment has a protrusion 23 formed in a striped shape in a part of the contact portion with the object to be coated 10, and is obtained by using this. The coated area ratio of the object to be coated 10 was 25%.

[Example 3]
The liquid 11 was applied to the object to be coated 10 in the same manner as in Example 1 except that the coating roll 2C (see FIG. 6) was used instead of the coating roll 2 (see FIG. 3). As shown in FIG. 6, in the coating plate 21 used in Example 3, the protrusions 23 are formed in a scattered spot shape in a part of the contact portion with the object to be coated 10, and the coating plate 21 can be obtained by using this. The coated area ratio of the coated object 10 was 25%.

[Comparative example]
Examples except that the so-called zero-touch coating was performed in the coating process of the liquid 11, that is, the liquid 11 was applied in a state where the object to be coated 10 was not pressed by the coating plate 21 and both were in contact with each other. In the same manner as in 1, the liquid 11 was applied to the object to be coated 10.

For each Example and Comparative Example, the thickness of the object to be coated 10 immediately after the application of the liquid 11 (covered with a pair of coating rolls 2 and 3) with respect to the thickness of the object 10 to be coated before the application of the liquid 11. When the coated object 10 is temporarily pressed and compressed, the ratio (hereinafter, also referred to as "thickness ratio after liquid coating") of the object to be coated 10 immediately after the pressing is released is calculated. did. The thickness of the object to be coated 10 before and immediately after the application of the liquid 11 was measured by the following method.

<Thickness measurement method>
Place the object to be measured (the object to be coated before or immediately after applying the liquid) on a horizontal place without wrinkles or bending, and measure the thickness under a load of 5 ^{cN / cm 2.} A thickness gauge PEACOCK DIAL UPRIGHT GAUGES R5-C (manufactured by OZAKI MFG.CO.LTD.) Was used to measure this thickness. At this time, a circular or square plate (acrylic plate with a thickness of about 5 mm) is arranged between the tip of the thickness gauge and the measurement portion of the object to be measured, and the load is 5 cN / cm ² . The size of the plate was adjusted so as to be.

[Evaluation test of coating quality]
In each of the examples and comparative examples, the liquid 11 is applied to 100 sheets of the object to be coated 10, and the surface to be coated of the object 10 to be coated after the coating is visually observed, and the liquid 11 is faint. The case where no unevenness was observed was regarded as a pass, and the pass rate [= {passed number / 100} × 100)] was calculated. The results are shown in Table 1 below.

As shown in Table 1, in the comparative example in which the so-called zero-touch coating was performed, the coating quality at the passing level could not be obtained, whereas in each embodiment, the temporary compression degree of the object to be coated in the coating process was determined. Not zero, but a pair of coating rolls, including a coating roll, temporarily presses and compresses the object to be coated while bringing the liquid into contact with the surface of the compressed portion, resulting in an extremely high pass. It became a rate.

1 Liquid coating equipment 2,2A, 2B, 2C coating roll (coating roll)
20 Base roll 21 Coating plate 22 Standard part 23 Protruding part 3 Backup roll (coating roll)
4 Liquid supply unit 10 Work piece to be coated (article constituent material)
10A convex part (middle and high part)
11 Liquid (coating liquid)

Claims (10)

A liquid coating method in which a liquid is applied to the surface of an article constituent material used for manufacturing an absorbent article by using a pair of coating rolls in which outer peripheral surfaces are arranged facing each other at predetermined intervals. There,
By supplying and transporting the article constituent material between the pair of coating rolls in a state where the liquid is adhered to the coating plate forming one outer peripheral surface of the pair of coating rolls. It has a coating step of transferring the liquid of the coating plate to the surface of the article constituent.
The coated plate is non-impregnated with respect to the liquid and is non-impregnated.
The thickness of the article constituent material after the pressing is released is larger than the thickness at the time of compression by the pressing by the pair of coating rolls.
Unevenness is formed on the surface to be coated with the liquid in the article constituent material.
The concave portion of the surface to be coated is a portion having a relatively small basis weight and thickness in the article constituent material, and the convex portion of the object to be coated is a portion having a relatively small basis weight and thickness in the article constituent material. Both are large parts,
In the coating step, the article constituent material being conveyed between the pair of coating rolls is temporarily pressed by the pair of coating rolls to compress the surface of the compressed portion. A liquid coating method in which the liquid adhering to the coating plate is brought into contact with the liquid, and the liquid is applied to the concave portions and convex portions constituting the unevenness of the surface to be coated. The liquid coating method according to claim 1, wherein the article constituent material has a partially different basis weight. The liquid coating method according to claim 1 or 2 , wherein in the coating step, the article constituent material is temporarily compressed by 60% or more of the thickness. Claim 1 to compress the article constituent material so that the thickness of the article constituent material after the pressing by the pair of coating rolls is released exceeds 85% of the thickness of the article constituent material before the pressing. The liquid coating method according to any one of 3 to 3. The liquid coating method according to any one of claims 1 to 4 , wherein a protrusion is partially formed on the surface of the coating plate, and the liquid is adhered to the tip of the protrusion. The liquid coating method according to any one of claims 1 to 5 , wherein the liquid is heated and then adhered to the coating plate. A method of manufacturing an absorbent article comprising a laminate of the topsheet and the intake absorbent body,
A stacking compression step in which the surface sheet and the absorber are laminated and laminated, and the laminate is compressed in the thickness direction.
The laminated body is coated with the pair of coatings in a state where the liquid is adhered to the coating plate forming one outer peripheral surface of the pair of coating rolls in which the outer peripheral surfaces are arranged so as to face each other at a predetermined distance from each other. It has a coating step of transferring the liquid of the coating plate to the surface of the laminate by supplying and transporting the liquid between the rolls.
The coated plate is non-impregnated with respect to the liquid and is non-impregnated.
The thickness of the laminated body after the pressing is released is larger than the thickness at the time of compression by the pressing by the pair of coating rolls.
Unevenness is formed on the surface to be coated with the liquid in the laminated body.
The concave portion of the surface to be coated is a portion having a relatively small basis weight and thickness in the laminated body, and the convex portion of the surface to be coated has a relatively small basis weight and thickness in the laminated body. It ’s a big part,
In the coating step, the laminated body being conveyed between the pair of coating rolls is temporarily pressed by the pair of coating rolls to be compressed, and the surface of the compressed portion is pressed. A method for producing an absorbent article, in which the liquid adhering to the coating plate is brought into contact with the liquid, and the liquid is applied to the concave portions and convex portions constituting the unevenness of the surface to be coated. It has a bulk recovery step of heating the surface sheet to perform a bulk recovery treatment.
The method for producing an absorbent article according to claim 7 , wherein in the stacking compression step, the surface sheet subjected to the bulk recovery treatment and the absorber are laminated in layers. The absorbent article according to claim 7 or 8 , wherein the degree of compression of the laminated body in the laminated compression step is equal to or less than the degree of compression by the pair of coating rolls in the coating step. Manufacturing method. In the laminated compression step, the laminated body is supplied between a pair of compression rolls and conveyed to be compressed in the thickness direction.
The absorbability according to claim 9 , wherein the clearance between the pair of compression rolls is the same as or larger than the clearance between the pair of coating rolls to which the laminate is transported and supplied in the coating step. Manufacturing method of goods.

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