METHOD OF PRODUCING CLEANING MEMBER

- UNICHARM CORPORATION

To provide a novel production method and a novel production system that are suitable for producing a cleaning member having an excellent cleaning performance and that realize efficient production. The present invention is a method of producing a cleaning member obtained from a multi-layer web comprising at least a fiber bundle and a belt-shaped nonwoven fabric, wherein the method comprises at least the step of connecting the ends of the at least two the fiber bundles by melt-bonding.

Skip to: Description  ·  Claims  · Patent History  ·  Patent History
Description
TECHNICAL FIELD

The present invention relates to a method of producing a cleaning member, and a system of producing a cleaning member.

BACKGROUND ART

Various types of cleaning members capable of trapping dust, trash, etc., are conventionally known, and methods for producing the various types have been examined from a variety of viewpoints.

For example, Patent Document 1 proposes a method of producing a cleaning member comprising the steps of:

    • stacking a belt-shaped inner fibrous layer consisting of continuous fiber bundles and a belt-shaped sheet member, both being partially joined to form a first continuous body, followed by the formation of a second continuous body in a similar manner, and, after the first and the second continuous bodies are stacked and partially fixed, stacking and fixing a belt-shaped outer fibrous layer consisting of continuous fiber bundles on each of the inner fibrous layer side of the first and the second continuous bodies;
    • cutting the laminate obtained in the preceding step into a predetermined length; and
    • applying a compressed air to the fibrous layer part of the cut laminate to open the fiber bundles;
    • wherein the belt-shaped inner fibrous layer and outer fibrous layer are each composed of fiber bundles consisting of curled fibers bent in a zig-zag form, a vertical height between the alternating peaks and troughs of the above curled fiber is 0.1 to 0.7 mm, and, during the step of opening the above fiber bundles, the fiber bundles in the cut laminate are teased so that the entire periphery of the cleaning member is covered with brush tips consisting of the fiber of the fiber bundles.

Also, Patent Document 2, for example, proposes a method of producing a cleaning member, wherein

    • a first continuous body having a first fibrous layer consisting of continuous fiber bundles and a first belt-shaped member, in which both longitudinal ends of the first belt-shaped member are folded to be stacked and fixed, and the first fibrous layer is stacked on and fixed to the outer face side of the first belt-shaped member, and a second continuous body having a second fibrous layer consisting of continuous fiber bundles and a second belt-shaped member, in which both longitudinal ends of the second belt-shaped member are folded to be stacked and fixed, and the second fibrous layer is stacked and fixed onto the outer face side of the second belt-shaped member, are produced, and after the first continuous body and the second continuous body thus produced are stacked and joined to each other, a third fibrous layer and a fourth fibrous layer, each consisting of continuous fibrous bundles, are stacked on the first fibrous layer and the second fibrous layer, respectively, and fixed to form a laminate, then the laminate thus formed is cut to obtain individual cleaning members,
    • characterized in that the method comprises the steps of:
    • intermittently forming broken guide lines spanning the entire lateral area of each of the first belt-shaped member and the second belt-shaped member in the first belt-shaped member and the second belt-shaped member so that a central part sandwiched by a pair of broken guide lines and an external part provided consecutively in the central part via the broken guide lines are formed in each of the first belt-shaped member and the second belt-shaped member, respectively;
    • joining the first belt-shaped member and the second belt-shaped member, after forming the broken guide lines, to the first fibrous layer and the second fibrous layer with a central continuous seal line spanning the entire lateral area of each of the first fibrous layer and the second fibrous layer to produce the first continuous body and the second continuous body;
    • stacking the first continuous body and the second continuous body to join them with side noncontinuous seals spanning the entire lateral area of the first fibrous layer and the second fibrous layer;
    • further stacking and fixing a third fibrous layer and a fourth fibrous layer onto the first fibrous layer of the first continuous body and the second fibrous layer of the second continuous body to form the laminate;
    • excising the external part flanking the central part, leaving the central part sandwiched by the pair of broken guide lines, from each of the cut first belt-shaped member and the cut second belt-shaped member, after cutting the laminate; and
    • opening the cut first through fourth fibrous layers, so as to tease them randomly in three-dimensional directions, after cutting the laminate.

Furthermore, Patent Document 3, for example, proposes a method of producing a cleaning member comprising the steps of:

    • laminating a continuous body comprising a four-layered long fibrous layer in which fiber bundles are oriented in one direction, a continuous body comprising two long scraping sheets, and a continuous body comprising two long base sheet in the order of the continuous body comprising the fibrous layer, the continuous body comprising the scraping sheets, the continuous body comprising the fibrous layer, the continuous body comprising the two base sheets, the continuous body comprising the fibrous layer, the continuous body comprising the scraping sheets, and the continuous body comprising the fibrous layer,
    • joining the continuous bodies with one another at a predetermined distance in the lateral direction to prepare a cleaning member continuous body, and then
    • cutting, in the lateral direction, the cleaning member continuous body at the junctions between the continuous body of the fibrous layer and the continuous body of the base sheet and the continuous body of the scraping sheet to obtain a plurality of the cleaning member.

CITATION LIST Patent Literature

  • [PTL 1] U.S. Pat. No. 4,878,988
  • [PTL 2] U.S. Pat. No. 4,738,311
  • [PTL 3] U.S. Pat. No. 4,675,218

SUMMARY OF INVENTION Technical Problem

However, there is currently a need for a novel production method and a production system of producing cleaning members capable of trapping dust, trash, etc., in a more efficient manner. Considering the above circumstance, the present invention was found by the present inventors as a result of intensive and extensive investigation.

Thus, it is an object of the present invention to provide a novel production method and a novel production system that are suitable for producing a cleaning member having excellent cleaning performance and that realize efficient production.

Solution to Problem

In order to obtain the above objective, the present invention provides a method of producing a cleaning member obtained from a multi-layer web comprising at least a fiber bundle and a belt-shaped nonwoven fabric, wherein the method of producing the cleaning member comprises at least the step of connecting the ends of at least two the fiber bundles.

Effects of Invention

In accordance with the present invention, a novel production method and a novel production system that are suitable for producing a cleaning member having an excellent cleaning performance and that realize efficient production is provided.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a cleaning member produced by an embodiment of the production method and/or production system of the present invention and a holding tool that is fixed to the cleaning member.

FIG. 2 is a sectional view of FIG. 1 along a X-X line.

FIG. 3 is a plan view of the cleaning member shown in FIG. 1.

FIG. 4 is a schematic view for explaining a method and/or a system of producing the cleaning member shown in FIG. 1.

FIG. 5 is a view that illustrates an embodiment of the production method and/or the production system of the present invention.

FIG. 6 is a view that schematically illustrates a state in which the ends of two fiber bundles are connected.

FIG. 7 is a view that illustrates an embodiment of a step in which a phototube is used for detection and/or a device in which a phototube is used for detection.

DESCRIPTION OF EMBODIMENTS Method of Producing a Cleaning Member

The method of producing the cleaning member of the present invention will now be explained in detail below.

The method of producing a cleaning member according to the present invention is a method of producing a cleaning member obtained from a multi-layer web comprising at least a fiber bundle and a belt-shaped nonwoven fabric,

    • wherein the method comprises at least the step of connecting the ends of at least two fiber bundles by melt-bonding (aspect 1).

The method of producing a cleaning member according to the present invention is a novel production method that is suitable for producing a cleaning member having excellent cleaning performance and that realizes efficient production. The method of producing a cleaning member according to the present invention can continuously supply fiber bundles and thus excels in high-speed production and further in continuous production.

In aspect 1, as a step after the step of connecting the ends of at least two fiber bundles, it may be preferable to further comprise the step of opening the at least two fiber bundles (aspect 2). According to aspect 2, after connecting the ends of at least two fiber bundles, at least two fiber bundles are opened, which makes it easy to detect the connected ends without opening them with a phototube.

In aspect 1 or 2, it may be preferable to further comprise a detection step in which the ends of the above connected at least two fiber bundles are detected by a detecting part (aspect 3). The detecting part may preferably be disposed before the step of forming a multi-layer web by stacking fiber bundles described below and the above belt-shaped nonwoven fabric. As the detecting part, for example, a phototube, a camera etc. may be mentioned. In a phototube, a light-emitting part and a light-receiving part are disposed at a predetermined lateral position sandwiching a fiber bundle and a non-contacting fiber bundle, and a detecting means integrated with the light-emitting/light-receiving part is disposed at a predetermined lateral position of a fiber bundle and a non-contacting fiber bundle. The camera detects the position of the ends of fiber bundles by binarizing an image input by the camera using predetermined parameters.

In aspect 3, it may be preferable to further comprise a step of forming a multi-layer web by stacking the above at least two fiber bundles comprising the ends of the above connected at least two fiber bundles, the ends being detected by the above detecting part, and the above belt-shaped nonwoven fabric, and a step of fixing the multi-layer web (aspect 4).

In aspect 4, the step of fixing the multi-layer web may preferably be a melt-bonding step (aspect 5). In another embodiment, the fixing step is a step of fixing by hot-melt.

In aspect 4 or 5, it may be preferable to further comprise a step of cutting the fusion-bonded multi-layer web in the lateral direction, and a step of ejecting the multi-layer web comprising the above ends of the above cut at least two fiber bundles (aspect 6).

In the method of producing a cleaning member according to the present invention, two or more of aspects 1 through 6 can be combined.

(System of Producing a Cleaning Member)

The system of producing a cleaning member according to the present invention will now be explained in detail below.

The system of producing a cleaning member according to the present invention is a system of producing a cleaning member that is obtained from a multi-layer web containing a fiber bundle and a belt-shaped nonwoven fabric, the system being at least equipped with a device for connecting the ends of at least two fiber bundles by melt-bonding (aspect 7).

The system of producing a cleaning member according to the present invention is a novel production system that is suitable for producing a cleaning member having an excellent cleaning performance and that realizes efficient production. The system of producing a cleaning member according to the present invention can continuously supply fiber bundles, and thus excels in high-speed production and further in continuous production.

In aspect 7, it may be preferable to be further equipped with a device for opening at least two fiber bundles after connecting the ends of the at least two fiber bundles (aspect 8). According to aspect 8, the at least two fiber bundles are opened after the ends of the at least two fiber bundles were connected, and thus it becomes easier to detect the connected ends without opening the bundles with a phototube, etc.

In aspect 7 or 8, it may be preferable to be further equipped with a device for detecting the ends of the connected at least two fiber bundles by the detecting part (aspect 9). The detecting part may preferably be disposed before the step of forming a multi-layer web by stacking fiber bundles described below and the above belt-shaped nonwoven fabric. As the detecting part, for example, a phototube, a camera etc. may be mentioned. In a phototube, a light-emitting part and a light-receiving part are disposed at a predetermined lateral position sandwiching a fiber bundle and a non-contacting fiber bundle, and a detecting means integrated with the light-emitting/light-receiving part is disposed at a predetermined lateral position of a fiber bundle and a non-contacting fiber bundle. The camera detects the position of the ends of fiber bundles by binarizing an image input by the camera using predetermined parameters.

In aspect 9, it may be preferable to be further equipped with a device for forming a multi-layer web by stacking the above at least two fiber bundles comprising the ends of the above connected at least two fiber bundles, the ends being detected by the above detecting part, and the above belt-shaped nonwoven fabric, and a device of melt-bonding the multi-layer web (aspect 10).

In aspect 10, it may be preferable to be further equipped with a device for cutting the fusion-bonded multi-layer web in the lateral direction, and a device for ejecting the multi-layer web comprising the above ends of the above cut at least two fiber bundles (aspect 11).

In the system of producing a cleaning member according to the present invention, two or more of aspects 7 through 11 can be combined.

Embodiments of the method and the system of producing a cleaning member according to the present invention are explained in more detail with reference to FIG. 1 through FIG. 7. The method and the system of producing a cleaning member according to the present invention are not limited to the embodiments of the present invention represented by FIG. 1 through FIG. 7 in a range without departing from the scope and spirit of the present invention.

First, a cleaning member 1 will be explained with reference to FIG. 1 through FIG. 3.

FIG. 1 is a perspective view of a holding tool that is fixed to the cleaning member 1, FIG. 2 is a sectional view of FIG. 1 along the X-X line, and FIG. 3 is a plan view of the cleaning member 1 shown in FIG. 1. In the explanation below, while “top” may be referred to as an upper side and “bottom” as a downside in FIG. 2, “top” and “bottom” in FIG. 2 are only used for the sake of explanation, and do not intend to limit the actual upper or lower direction of the cleaning member 1.

As shown in FIG. 1 through FIG. 3, the cleaning member 1 is equipped with a brush sheet 2, a base sheet 12 stacked on the upper side of the brush sheet 2, and a holding sheet 13 stacked on the upper side of the base sheet 12.

As shown in FIG. 1 through FIG. 3, in the cleaning member 1, a receiving part 14 into which the insertion part 16 of a holding tool 15 is to be inserted has been formed in between the base sheet 12 and the holding sheet 13. As shown in FIG. 1 through FIG. 3, in the cleaning member 1, two receiving parts 14 have been formed so as to receive the insertion part 16 that was divided into two. While the number of the receiving parts 14 in this embodiment is two, the number of the receiving parts can be changed as appropriate depending on the number of divisions of the insertion part 16. In another embodiment, there may be mentioned an embodiment in which the number of the insertion parts 14 is three or more.

As shown in FIG. 2, the brush sheet 2 has a fibrous member of a four-layer structure comprising a first fibrous member 3, a second fibrous member 4 stacked at the downside of the first fibrous member 3, a third fibrous member 5 stacked at the downside of the second fibrous member 4, and a fourth fibrous member 6 stacked at the downside of the third fibrous member 5, and a sheet with slits 7 stacked at the downside of the four-layer structured fibrous member (at the downside of the fourth fibrous member 6). The fibrous member of the brush sheet 2 according to the present embodiment has a four-layer structure, but the layer structure of the fibrous member can be changed as appropriate. In another embodiment, there may be mentioned an embodiment in which the fibrous member has a one-layer structure, a two-layer structure or a three-layer structure, and in still another embodiment, the fibrous member has a structure of five-layer or more. Also, while the brush sheet 2 in the present embodiment has a sheet with slits 7, the presence or absence of the sheet with slits 7 may be selected as appropriate. In another embodiment, the sheet with slits 7 has been omitted.

The first through fourth fibrous members 3 through 6 are fiber bundles to which an oil solution is attached, and thus is a dust adhering agent (for example, an oil solution comprising liquid paraffin as an active ingredient) having an effect of promoting the adherence of dust, trash, etc.

A fiber bundle is, for example, a tow, preferably an opened tow. As described in JIS L 0204-3:1998, 3.1.24, “tow” indicates a bundle of an extremely large number of filaments.

A fiber bundle may be a bundle of slit fibers (fibers made by cutting a film into reed-shaped part and then stretching them), split fiber (fibers made by subdividing reed-shaped parts of film into a network structure), etc.

As fiber bundles, there can be mentioned, for example, fiber bundles consisting of or comprising thermoplastic fibers, etc. As raw materials constituting fiber bundles, there can be mentioned, for example, polyethylene, polypropylene, polyethylene terephthalate, nylon, rayon, etc., and the type of fibers constituting fiber bundles include, for example, single fibers, composite fibers (for example, core-in-sheath composite fibers, side-by-side composite fibers), etc. From the viewpoint of thermal bondability, composite fibers may preferably be core-sheath type composite fibers, and more preferably core-sheath type composite fibers in which the melting point of the core is higher than that of the sheath.

As a preferred core-in-sheath composite fiber, there can be mentioned core-sheath type composite fibers in which the core consists of polypropylene or polyethylene terephthalate and the sheath consists of polyethylene, and more preferably core-sheath type composite fibers in which the core consists of polyethylene terephthalate and the sheath consists of polyethylene.

The purity of a fiber constituting fiber bundles may preferably be 1-500 dtex, more preferably 2-10 dtex. Fiber bundles may comprise a plurality of fibers having the same purity, or a single fiber or a plurality of fibers having a different purity.

In the present embodiment, each fiber constituting fiber bundles is composed of curled fibers. By allowing each fiber to be composed of curled fibers, fiber bundles can be made bulky and can be made a structure that permits easy trapping of dust etc. at the curled parts. In another embodiment, there can be mentioned an embodiment in which each fiber constituting fiber bundles is composed of noncurled fibers.

Similarly to the base sheet 12 and the holding sheet 13, as described below, the sheet with slits 7 is composed of a nonwoven fabric consisting of a thermoplastic fiber (a thermally fusion-bondable fiber) or a nonwoven fabric comprising a thermoplastic fiber, and is formed in a rectangular shape of the same width and the same length as those of the base sheet 12. In the sheet with slits 7, saw-edged cuts (not shown) are made at a given distance along the entire sheet with slits 7, and with the cuts, saw-edged reed-shaped parts (not shown) are formed over the entire length along both lateral ends of the sheet with slits 7.

As shown in FIG. 1 through FIG. 3, a base sheet 12 and a holding sheet 13 are stacked sequentially on the upper side of the first fibrous member 3 of the brush sheet 2, and a receiving part 14 into which the insertion part 16 of the holding tool 15 is to be inserted is formed in between the base sheet 12 and the holding sheet 13.

As shown in FIG. 3, the base sheet 12 and the holding sheet 13 have a rectangular form, and the lateral dimension (the direction of left to right in FIG. 3) of both sheets is set to be the same, and the longitudinal dimension (the vertical direction in FIG. 3) is set to be longer in the base sheet 12 so that both longitudinal ends of the base sheet 12 protrudes by a predetermined length from both longitudinal ends of the holding sheet 13, with the holding sheet 13 being stacked on the upper side of the base sheet 12.

The base sheet 12 and the holding sheet 13 are made of a nonwoven fabric consisting of a thermoplastic fiber (thermally fusion-bondable fiber) or a nonwoven fabric comprising a thermoplastic fiber. As thermoplastic fibers, for example, a polyethylene fiber, a polypropylene fiber, a polyethylene terephthalate fiber, a composite fiber of polyethylene and polyethylene terephthalate, and a composite fiber of polyethylene and polypropylene, such as core-sheath type composite fibers in which the core is composed of polyethylene terephthalate and the sheath is composed of polyethylene can be mentioned. As the type of nonwoven fabric, for example, a thermal bond nonwoven fabric, a spunbonded nonwoven fabric, a spunlace nonwoven fabric and the like can be mentioned.

In another embodiment, there can be mentioned an embodiment in which the base sheet and the holding sheet are made of a thermoplastic resin film such as a polyethylene film and a polypropylene film, and in still another embodiment, the base sheet and the holding sheet are made of a laminate sheet comprising a nonwoven fabric and a resin film.

The base sheet 12 and the holding sheet 13 are integrally fusion-bonded to all the layers (the first fibrous member 3, the second fibrous member 4, the third fibrous member 5, the fourth fibrous member 6, and the sheet with slits 7) of the brush sheet 2 through a first melt bonded part forming device 158 described below, and in the cleaning member 1, a first melt-bonding part 8 longitudinally extending in the central part is formed as shown in FIG. 1 through FIG. 3. Furthermore, at both ends (lateral ends in FIG. 2) of the first melt-bonding part 8, the base sheet 12 and the holding sheet 13 are integrally bonded to one layer (the first fibrous member 3) of the brush sheet 2 through a second melt bonded part forming device 134 described below, and in the cleaning member 1, two second melt-bonding parts 11 are longitudinally formed. Each of the two second melt-bonding parts 11 is intermittently formed. Since the first fibrous member 3 is fusion-bonded to the base sheet 12 and the holding sheet 13, the first fibrous member 3 follows the movement of these sheets 12 and 13, and thus the brush sheet 2 tends to further expand during use, resulting in an improved cleaning efficiency.

The base sheet 12 and the holding sheet 13 are fusion-bonded to all the layers (the first fibrous member 3, the second fibrous member 4, the third fibrous member 5, the fourth fibrous member 6, and the sheet with slits 7) of the brush sheet 2 in the first melt-bonding part 8, and are fusion-bonded to the first fibrous member 3 of the brush sheet 2 in two second melt-bonding parts 11. This results in the formation of a pair of receiving parts 14, which extends in the longitudinal direction of the base sheet 12 and the holding sheet 13 and which is a saclike space opening on both longitudinal ends, compartmentalized by the first melt-bonding part 8 and two second melt-bonding parts 11, thereby enabling the insertion part 16 of the holding tool 15 to be inserted into the receiving part 14.

The base sheet 12 and the holding sheet 13 are fusion-bonded to the first fibrous member 3 of the brush sheet 2 at the central part thereof through a second melt bonded part forming device 134 described below, and in the cleaning member 1, a pair of melt-bonding lines 18 are formed at a predetermined distance in the lateral direction of the base sheet 12 and the holding sheet 13, as shown in FIG. 3, with a first melt-bonding part 8 being formed in between the pair of melt-bonding lines 18. The pair of melt-bonding lines 18 are a landmark for monitoring the position of the first melt-bonding part 8 during the production step, and by monitoring whether the first melt-bonding part 8 is disposed in between the pair of the thermal melt-bonding lines 18 with a sensor etc., good items and defective items can be sorted out.

As shown in FIG. 1 through FIG. 3, two second melt-bonding parts 11 are intermittently provided at several places in the longitudinal direction of the base sheet 12 and the holding sheet 13, and by engaging an arc-like protrusion 16a at each insertion part 16 of the holding tool 15 with the non-fusion-bonded part of the two second melt-bonding parts 11, each insertion part 16 of the holding tool 15 is prevented from coming off each receiving part 14.

As shown in FIG. 1, saw-edged slits 20a are provided at each given distance along the longitudinal direction in both lateral ends (the external parts of two second melt-bonding parts 11) of the base sheet 12 and the holding sheet 13, and with the slits 20a, a plurality of reed-shaped parts 20, both ends of which are saw-edged, are provided. In another embodiment, there can be mentioned an embodiment in which no saw-edged slits 20a are provided in the base sheet 12 and the holding sheet 13, and thus reed-shaped parts 20 are not provided.

As shown in FIG. 1, the holding tool 15 has a pair of rectangular plate-shaped insertion parts 16 disposed in parallel to each other, a pair of arc-like protrusions 16a protruding from the outer face of both longitudinal ends of each insertion part 16, and a holder part 17 provided integrally on one end of the insertion part 16, and is made, for example, of plastic etc.

By inserting both insertion parts 16 of the holding tool 15 into both insertion parts 14 of the cleaning member 1, and engaging the protrusions 16a with two second melt-bonding parts 11, the cleaning member 1 can be mounted to the holding tool 15. By holding the holder part 17 of the holding tool 15, and allowing the brush sheet 2 to come into contact with a target cleaning site to move it in the desired direction, dust, etc., at the target cleaning site are trapped by the brush sheet 2, resulting in the cleaning of the target cleaning site.

The cleaning member shown in FIG. 1 through FIG. 3 is an example of a cleaning member that can be produced by the method and system of producing a cleaning member according to the present invention. The method of producing a cleaning member and the system of producing a cleaning member according to the present invention can be used in producing cleaning members as described in, for example, Japanese Unexamined Patent Publication Nos. 2000-296083, 2003-265390, 2003-268663, 2004-223692, 2005-046645, 2005-095665, 2005-111284, 2005-137929, 2005-137930, 2005-137931, 2005-144198, 2005-169148, 2005-199077, 2005-230573, 2005-237975, 2006-015164, 2006-034990, 2006-141483, 2007-135774, 2007-209460 and 2007-209461, 2007-029136, 2007-111297, 2007-135666, 2007-136156, 2007-159612, 2007-236690, 2008-006260, 2008-119171, and 2007-029135, the entire disclosures of which are incorporated herein by reference. The method of producing a cleaning member and the system of producing a cleaning member according to the present invention can be used to produce a cleaning member as described in, for example, U.S. Pat. No. 6,554,937B, US2002/148061A, US2003/0000934A, US2004/0149095A, US2005/0005381A, US2005/039285A, US2005/097695A, US2005/097696A, US2005/132521A, US2005/177967A, US2005/188490A, US2005/193513A, US2005/193514A, US2005/198760A, US2006/016035A, US2006/016036A, US2006/101601A, US2009/165230A and US2009/172904A, as well as US2009/049633A, US2009/255078A and US2010/154156A, the entire disclosures of which are incorporated herein by reference.

Next, an embodiment of a method and a device for producing a cleaning member 1 will be explained with reference to FIG. 4.

FIG. 4 is a schematic view for explaining a method and the device for producing a cleaning member 1, and in the present embodiment, the method of producing the cleaning member 1 is carried out using a device 100 shown in FIG. 4 to produce the cleaning member 1.

In the present embodiment, the method of producing the cleaning member 1 comprises the following step 1 and step 2.

[Step 1] A step of opening a fiber bundle—a step of conveying it.

[Step 2] A step of producing a multi-layer web using fiber bundles and excising (cutting out) the cleaning member 1 from the multi-layer web.

<Step 1>

Hereinbelow, step 1 will be explained.

In the present embodiment, step 1 comprises the following step 1a and step 1b.

[Step 1a] A step of opening a first fiber bundle F1 through a fourth fiber bundle F4.

[Step 1b] A step of conveying the first fiber bundle F1 through the fourth fiber bundle F4.

According to the present embodiment, while step 1 comprises step 1a, the presence or absence of step 1a can be selected as appropriate depending on the type etc. of the fiber bundle used. In another embodiment, an embodiment in which step 1a is omitted can be mentioned. For example, when fiber bundles are composed of a noncurled fiber, step 1a can be omitted.

[Step 1a]

Hereinbelow, step 1a will be explained with reference to a step of opening the first fiber bundle F1 by way of example, and steps of opening other fiber bundles can be carried out in a similar manner.

The first fiber bundle F1 composed of a curled fiber is continuously extracted from a housing container (not shown), and conveyed to first nip rolls 102a and 102b revolving at a constant peripheral velocity V1. The first fiber bundle F1 that passed through the first nip rolls 102a and 102b passes through a plurality of tension rolls 104, and is conveyed to second nip rolls 106a and 106b revolving at a peripheral velocity V2.

The peripheral velocity V2 of the second nip rolls 106a and 106b is faster than the peripheral velocity V1 of the first nip rolls 102a and 102b. Due to the difference in the rim speed, tension is imparted to the first fiber bundle F1 between the first nip rolls 102a and 102b and the second nip rolls 106a and 106b, resulting in the opening of the first fiber bundle F1.

Each tension roll 104 is formed, for example, of a solid steel, and the weight has been adjusted to require a significant degree of force for revolving. Thus, during the movement of the first fiber bundle F1, while rotating each tension roll 104, from the first nip rolls 102a and 102b toward the second nip rolls 106a and 106b, the moving speed of the first fiber bundle F1 has been adjusted not to increase abruptly.

In order to attain the gradual opening of the first fiber bundle F1, each tension roll 104 has been disposed so as to lengthen the distance between the first nip rolls 102a and 102b and the second nip rolls 106a and 106b.

The first fiber bundle F1 that passed through the second nip rolls 106a and 106b passes through an air supplier 108 and is conveyed to third nip rolls 112a and 112b. The peripheral velocity V3 of the third nip rolls 112a and 112b is slower than the peripheral velocity V2 of the second nip rolls 106a and 106b. Due to the difference in the rim speed, tension of the first fiber bundle F1 is relieved between the second nip rolls 106a and 106b and the third nip rolls 112a and 112b, resulting in the opening of the first fiber bundle F1 as well as the widening of the width of the first fiber bundle F1.

On the first fiber bundle F1 that is conveyed from the second nip rolls 106a and 106b to the third nip rolls 112a and 112b, air is blown from the air supplier 108, resulting in the further opening of the first fiber bundle F1.

According to the present embodiment, while the first fiber bundle F1 is opened using the application and release of tension and air blowing, the method of opening can be changed as appropriate. In another embodiment, there can be mentioned an embodiment in which either of the application and release of tension or air blowing is used, and in still another embodiment, there can be mentioned an embodiment in which another method of opening is used in addition to the application and release of tension and air blowing. Also in the present embodiment, while the first through third nip rolls are used in the application and release of tension, the number of nip rolls can be changed as appropriate. In another embodiment, there can be mentioned an embodiment in which additional nip rolls are used for the application and release of tension in addition to the first through third nip rolls.

An oil solution is contained in an oil solution tank 114. In the present embodiment, the oil solution contained in the oil solution tank 114 is a dust-adhering oil solution (such as an oil solution comprising liquid paraffin as an active ingredient) having an effect of promoting the adsorption of dust etc.

[Step 1b]

Hereinbelow, step 1b will be explained with reference to a step of conveying the first fiber bundle F1 by way of example, and a step of conveying other fiber bundles can be carried out in a similar manner.

After passing through the third nip rolls 112a and 112b, the first fiber bundle F1 passes through a first phototube 181, and proceeds to a merging part 132. Similarly, the second through the fourth fiber bundles F2 through F4, after passing through the third nip rolls (not shown), pass through a second phototube 182, a third phototube 183 and a fourth phototube 184, and proceeds to merging parts 136, 138 and 140, respectively.

<Step 2>

Hereinbelow, step 2 will be explained.

In the present embodiment, step 2 comprises the following step 2a through step 2c.

[Step 2a] A step of stacking a fiber bundle that underwent through step 1b and another member (a belt-shaped nonwoven fabric in the present embodiment) to form a multi-layer web.

[Step 2b] A step of fixing the fiber bundle and another member contained in the multi-layer web.

[Step 2c] A step of excising individual cleaning members 1 from the multi-layer web.

[Step 2a]

Hereinbelow, step 2a will be explained.

In the present embodiment, the other members that are stacked with the fiber bundles that underwent the step 1b are belt-shaped nonwoven fabrics 121, 123 and 151. In another embodiment, one or two of these belt-shaped nonwoven fabrics are stacked with the fiber bundles that underwent the step 1b, and in still another embodiment, another belt-shaped nonwoven fabric, in addition to these belt-shaped nonwoven fabrics, is stacked with the fiber bundles that underwent the step 1b. In any of the embodiments, the order of stacking is not limited, but preferably stacking may be carried out so that the belt-shaped nonwoven fabric is positioned at the outermost layer.

The belt-shaped nonwoven fabrics 121 and 123 correspond to the base sheet 12 and the holding sheet 13, respectively, of the cleaning member 1. The belt-shaped nonwoven fabric 121 is continuously curled out from an nonwoven fabric roll 120, and is conveyed intermittently by passing through a dancer roll 124 comprising a plurality of rolls provided in two vertical stages wherein a roll located at the lower stage fluctuates vertically. Similarly, the belt-shaped nonwoven fabric 123 is continuously curled out from an nonwoven fabric roll 122, and is conveyed intermittently by passing through a dancer roll 126 comprising a plurality of rolls provided in two vertical stages wherein a roll located at the lower stage fluctuates vertically. As used herein “is conveyed intermittently” means that the belt-shaped nonwoven fabrics 121 and 123 are conveyed by repeating the steps of proceeding by a given distance (for example, roughly the lateral length of the cleaning member 1) and then stopping conveying for a certain period of time. Thus, by the intermittent conveyance of the belt-shaped nonwoven fabrics 121 and 123, the time required to fusion-bond the constituent elements of the multi-layer web described below can be secured.

The belt-shaped nonwoven fabrics 121 and 123 form a multi-layer web S1 at a merging part 128, and the multi-layer web S1 passes through a gather cutter 130 in which saw-edged blades (not shown) are intermittently formed on the surface thereof in a circumferential direction. This results in the formation of cuts corresponding to cuts 20a (see FIG. 1) in the base sheet 12 and the holding sheet 13. And the multi-layer web S1 proceeds to a merging part 132.

At the merging part 132, the multi-layer web S1 merges with the first fiber bundle F1 that underwent the step 1, and the first fiber bundle F1 is stacked on the multi-layer web S1 to form a multi-layer web S2. The first fiber bundle F1 is configured to become loosened slightly in between the third nip rolls 112a and 112b and the merging part 132, and thus fulfills the same function as a dancer roll provided between them would do.

At merging parts 136, 138 and 140, the multi-layer web S2 merges sequentially with the second fiber bundle F2 through the fourth fiber bundle F4 that underwent the step 1, and the second fiber bundle F2 through the fourth fiber bundle F4 are stacked sequentially on the multi-layer web S2 to form a multi-layer web S3.

A belt-shaped nonwoven fabric 151 corresponds to the sheet with slits 7 of the cleaning member 1. The belt-shaped nonwoven fabric 151 is continuously curled out from the nonwoven fabric roll 150, and is intermittently conveyed by passing through a dancer roll 152, and then passes through a gather roll 154. The gather roll 154 has saw-edged blades (not shown) continuously formed on the surface of the roll in a circumferential direction, which results in the formation of saw-edged cuts (not shown) on the belt-shaped nonwoven fabric 151 that passed through the gather roll 154.

The belt-shaped nonwoven fabric 151 merges with the multi-layer web S3 at a merging part 156, and the belt-shaped nonwoven fabric 151 is stacked on the multi-layer web S3 to form a multi-layer web S4.

[Step 2b]

Hereinbelow, step 2b will be explained.

Before merging with the second fiber bundle F2 through the fourth fiber bundle F4, the multi-layer web S2 passes through a second melt bonded part forming device 134. The second melt bonded part forming device 134 fusion-bonds belt-shaped nonwoven fabrics 121 and 123 contained in the multi-layer web S2 to the first fiber bundle F1 to form two second melt-bonding parts 11 (see FIG. 3). This results in the melt-bonding of the multi-layer web S2 in the direction of the thickness thereof. In the present embodiment, while a heat sealing device is used as the second melt bonded part forming device 134, another heat sealing device (such as an ultrasonic sealing device) may be used.

The multi-layer web S4 passes through a first melt bonded part forming device 158. The first melt bonded part forming device 158 fusion-bonds the entire hole multi-layer web S4 to form a first melt-bonding part 8 (see FIG. 3) on the multi-layer web S4. This results in the melt-bonding of the multi-layer web S4 in the direction of the thickness thereof. In the present embodiment, while a heat sealing device is used as the first melt bonded part forming device 154, the heat sealing device can be changed as appropriate. In another embodiment, an ultrasonic sealing device is used.

[Step 2c]

Hereinbelow, step 2c will be explained. The multi-layer web S4 that passed through the first melt bonded part forming device 158 is cut by a cutting device 160, so that individual cleaning members 1 are excised. As described above, also, the multi-layer web S4 comprising the ends of the above connected at least two unopened fiber bundles, the ends being detected by the four phototubes (181 through 184), is ejected by an ejecting device 190. Since the distance from the detection point to the ejection point is constant, the number (N) of products present in the distance can be calculated by distance÷length of the product. When a shortage in the width is detected by the detecting part, a detection signal for width shortage is input into a programmable logic controller (PLC), in which the counting part of the PLC starts to add the number of sheets. When the number reaches a predetermined number, the ejecting device of the ejecting part is started to eject products having defective width. If a product having a Nth product number is only ejected, no defective product will enter into the finished products. In order to carry out secure ejection, products having a product number in the range of N±2 (N−2, N−1, N, N+1, N+2), or products having a product number in the range of N±1 (N−1, N, N+1) can be ejected.

The cleaning member 1 produced according to the present embodiment contains the sheet with slits 7, whereas a cleaning member produced by another embodiment does not contain the sheet with slits 7. In the cleaning member 1 produced by the present embodiment, the receiving part 14 is disposed on the face of the cleaning member 1, whereas in a cleaning member produced by another embodiment, the receiving part 14 is disposed in between any of adjacent fibrous members 3 through 6 by changing the order of stacking the base sheet 12 and the holding sheet 13 and the fibrous members 3 through 6. This makes it possible to use both faces of the cleaning member 1 in cleaning. At this time, in order to facilitate the insertion of the insertion part 16 into the receiving part 14, the longitudinal dimension (vertical dimension in FIG. 3) of the base sheet 12 and the holding sheet 13 may preferably be made longer than that of the fibrous members 3 through 6, and these dimensions can be arbitrarily determined. Also, at this time, the sheet with slits 7 may or may not be used, and the sheet with slits 7 may be disposed on both faces of the cleaning member 1.

FIG. 5 is a drawing that schematically illustrates that the first fiber bundle F1 in which ends b (the terminal end part of the one first fiber bundle F1 and the starting end part of the other first fiber bundle F1) of the first fiber bundle F1, each being housed in two housing containers, is discharged. It can be recognized that by fixing the ends b by melt-bonding such as heat sealing and adhesion, continuous production can be realized.

FIG. 6 is a drawing that schematically illustrates the enlargement of the ends b of two first fiber bundles F1. It can be recognized that the fixing part (the heat sealing part in FIG. 6) of the ends b is not opened even by undergoing the opening step.

FIG. 7 is a drawing that schematically illustrates a state in which the phototube 181 passes through the first fiber bundle F1 during the step of conveying the first fiber bundle F1.

The present application claims the benefit of the following patent applications, the entire disclosures of which are incorporated herein by reference:

    • (1) JP Patent Application No. 2012-289181 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (2) JP Patent Application No. 2012-289182 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (3) JP Patent Application No. 2012-289174 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (4) JP Patent Application No. 2012-289189 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application)
    • (5) JP Patent Application No. 2012-289175 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (6) JP Patent Application No. 2012-289188 filed on Dec. 29, 2012,
    • (7) JP Patent Application No. 2012-289179 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (8) JP Patent Application No. 2012-289177 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (9) JP Patent Application No. 2012-289184 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (10) JP Patent Application No. 2012-289178 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (11) JP Patent Application No. 2012-289176 filed on Dec. 29, 2012, and US patent application claiming priority thereof (filed on the same day as the present application),
    • (12) JP Patent Application No. 2013-002855 filed on Jan. 10, 2013, and US patent application claiming priority thereof (filed on the same day as the present application), as well as
    • (13) JP Patent Application No. 2013-002857 filed on Jan. 10, 2013, and US patent application claiming priority thereof (filed on the same day as the present application).

REFERENCE SIGNS LIST

1: cleaning member; 2: brush sheet (shaggy brush sheet); 3: first fibrous member; 4: second fibrous member; 5: third fibrous member; 6: fourth fibrous member; 7: sheet with slits; 8: first melt-bonding part; 11: second melt-bonding part; 12: base sheet; 13: holding sheet; 14: receiving part; 15: holding tool; 16: insertion part; 16a: protrusion; 17: holder part; 18: melt-bonding line; 20: reed-shaped part; 20a: slit; 100: cleaning member-producing device; 102a and b: first nip rolls; 104: tension roll; 106a and b: second nip rolls; 108: air supplier; 110: transcription roll; 112a and b: third nip rolls; 113: blade member; 114: oil solution tank; 120, 122 and 150: nonwoven fabric rolls; 121, 123 and 151: belt-shaped nonwoven fabrics; 124, 126 and 152: dancer rolls; 128, 132, 136, 138, 140 and 156: merging parts; 130: gather cutter; 134: second melt bonded part forming device; 154: gather roll; 158: first melt bonded part forming device; 160: cutting device; 181: first phototube; 182: second phototube; 183: third phototube; 184: fourth phototube; 190: ejecting device; 201: housing container; 202: housing container 2; 301: first non-revolving bar; 202: second non-revolving bar; 401: fiber bundle-holding roll.

Claims

1. A method of producing a cleaning member obtained from a multi-layer web comprising at least a fiber bundle and a belt-shaped nonwoven fabric, said method comprising the steps of:

connecting the ends of at least two fiber bundles by melt-bonding;
opening said at least two fiber bundles;
detecting the ends of said connected at least two fiber bundles by a detecting part;
forming a multi-layer web by stacking; said at least two fiber bundles including the ends of the connected at least two fiber bundles, the ends being detected by the detecting part, and the belt-shaped nonwoven fabric;
fixing the multi-layer web;
cutting the multi-layer web in a lateral direction; and
ejecting the multi-layer web comprising the ends of the cut at least two fiber bundles.

2. (canceled)

3. (canceled)

4. (canceled)

5. The method according to claim 1, wherein the step of fixing the multi-layer web is a melt-bonding step.

6. (canceled)

7. A system of producing a cleaning member obtained from a multi-layer web containing at least a fiber bundle and a belt-shaped nonwoven fabric,

the system being at least equipped with a device for connecting the ends of at least two fiber bundles by melt-bonding.

8. The system according to claim 7, further equipped with a device for opening the at least two fiber bundles after connecting the ends of the at least two fiber bundles.

9. The system according to claim 7, further equipped with a device for detecting the ends of the connected at least two fiber bundles by the detecting part.

10. The system according to claim 9, further equipped with

a device for forming a multi-layer web by stacking the at least two fiber bundles comprising the ends of the connected at least two fiber bundles, the ends being detected by the detecting part, and the belt-shaped nonwoven fabric, and
a device for fixing the multi-layer web.

11. The system according to claim 10, further equipped with

a device for cutting the fusion-bonded multi-layer web in the lateral direction, and
a device for ejecting the multi-layer web comprising the ends of the cut at least two fiber bundles.

12. The method according to claim 1, wherein said step of connecting comprises joining the end of one of said at least two fiber bundles on an outer surface of the end of the other of said at least two fiber bundles.

13. The method according to claim 1, wherein said ends of said connected at least two fiber bundles are not opened at said step of detecting by the detecting part.

14. The method according to claim 1, wherein the detecting part is located within a width of the at least two fiber bundles.

Patent History
Publication number: 20140182767
Type: Application
Filed: Jan 25, 2013
Publication Date: Jul 3, 2014
Applicant: UNICHARM CORPORATION (Shikokuchuo-shi)
Inventors: Hiroaki GOTO (Kanonji-shi), Takayuki MATSUMOTO (Kanonji-shi), Shigetomo TAKAHASHI (Kanonji-shi), Yuji YAMASHITA (Kanonji-shi)
Application Number: 13/749,722