WO2011128397A1

WO2011128397A1 - Method for attaching strips to a moving web

Info

Publication number: WO2011128397A1
Application number: PCT/EP2011/055880
Authority: WO
Inventors: Christoph Schmitz
Original assignee: Concepts For Success (C4S)
Priority date: 2010-04-15
Filing date: 2011-04-14
Publication date: 2011-10-20
Also published as: GB201006302D0; GB2479576A

Abstract

The present invention is a method and an equipment for applying a strip (e.g. a tape strip) of material to a web material whilst this is moving. The strip is applied to a separation line essentially cross-directionally oriented relative to the machine direction of the moving web. The present invention is particularly useful in the manufacturing of disposable absorbent articles, such as diapers, in particular when the orientation of the article is cross-directionally to the machine direction.

Description

Method for attaching strips to a moving web

Field of the invention

The present invention is a method for attaching a strip to a web material whilst the web is moving along its machine direction and the strip is attached to a cross-directionally oriented margin of the web. Such a method can suitably be applied in the manufacturing of disposable articles, such as diapers.

Background

The application of strips of material to a web is a widely used technique and in particular in the manufacturing of disposable absorbent articles a lot of effort has been spent on how to attach tape strips, see e.g. US5516567 (Roessler; K-C; 1996) or US3848594 (Buell, P&G). These conventional approaches have in common, that the longitudinal direction of the article is aligned with the machine direction of the web. The tapes are applied such that they extend laterally outwardly of the longitudinally extending margins of the article. They are essentially aligned with the longitudinally extending margins after a subsequent tape folding or tucking step has been completed, which also brings areas of the tape in contact with the respective opposite surface of the web.

At present, no solution is known to the applicant for attaching strips, such as tapes, to a web, such as a pre-form of a diaper, in particular at high production speed and when the strips are supposed to be affixed to a line which is not parallel to the manufacturing machine direction.

Summary

The present invention is a method for attaching a strip of material to a web moving along its machine direction, thereby defining a longitudinal direction of the web. The method comprises the steps of:

a) Providing a web, which may be a composite material, and moving the web on a web support means along its machine direction, the web exhibiting a longitudinal centreline and a first and a second longitudinally extending side margin, a major first web surface, and a major opposite web surface, which is oriented towards the web support means. Optionally, the web may have undergone a folding step, whereby one or more of the longitudinal side margins of the unfolded precursor web have been overfolded, so as to form new longitudinally extending side margins of the (folded) web.

b) Applying a separation line to the web, which intersects at least the first longitudinally extending side margin and which is predominantly CD-oriented.

c) Severing the web along the separation line from the first longitudinally extending side margin towards a severing endpoint whilst leaving the web essentially continuous.

d) Up folding a forward and/or a rearward folding region of said web away from the web support means, the folding region(s) having an essentially triangular shape delimited by the longitudinally extending side margins, the separation line portion extending from the longitudinally extending side margins up to the severing endpoint, and a resulting folding line.

e) Moving a folding means along the separation line, optionally concurrently severing the web according to step c), up to the severing end point, thereby overfolding the folding region(s).

f) Providing at least one strip of material, which may be a composite material, having a first and a second strip surface and comprising a first and a second strip portion positioned adjacently along the width direction of the strip, which may exhibit varying attachment properties, and which may comprise adhesive and/or mechanical fastening elements.

g) Positioning the strip such that the strip width is oriented essentially parallel to the separation line, and such that the first strip portion overlays the overfolded web region and is attached with its first surface to the major opposite surface, whilst the second strip portion protrudes over the overfolded web region whilst remaining essentially unattached to the major first web surface.

The method may further comprise the steps of

h) attaching the second strip portion to the major first web surface, and/ or

i) backfolding the overfolded web region with the strip by back-moving the folding means along the separation line, thereby changing the orientation of the strip, and / or j) overfolding the strip such that the second strip portion is folded onto the major first web surface, and optionally attaching the second strip portion to the major first web surface.

The up folding step d) may further comprise one or more of the following steps:

(m) varying the air suction or blowing adjacent to the web fold lines;

(n) inducing upfolding mechanically by positioning an elevated fold support plate on the web support means such that the web fold regions overlay the elevated fold support plate, whereby the margins of the plate correspond to the web fold lines;

(0) varying electrostatic forces adjacent to the web fold lines.

The method is particularly suitable in the manufacturing of an article such as a garment for being worn on the lower torso of a human wearer comprising a front, mid and rear portion corresponding to a front waist, crotch, and rear waist orientation during use, hereby defining a length orientation of the article, and wherein the length orientation of the article is essentially perpendicular (cross-directionally) to the web machine direction. In a further aspect, the present invention relates to an apparatus for applying a strip to a moving web, which comprises

a) web supply means;

b) web support means for moving the web along its machine direction;

c) a folding means which may comprise guide means such as plates, which may optionally having anti-adhesion surfaces;

d) a web separation means for an incomplete separation of web regions along a separation line which has essentially a CD-orientation;

e) a severing means, optionally integral or unitary with the web separation means; f) a web region upfolding means;

g) a web region overfolding means for folding regions of the web adjacent to the separation line;

h) a strip supply means;

i) a strip application means;

j) a web regions backfolding means for folding the web region back;

k) a strip overfolding means.

The separation means d) may be integral with one or more of the following:

(1) strip support means;

(ii) strip overfolding means.

Brief description of the Figures

Fig. 1 A-C show schematically a simple tape construction such as for disposable diapers. Fig. 2 A-C show schematically a so-called "Y-bond" such as being useful for disposable diapers.

Fig. 3 schematically depicts equipment elements according to the present invention. Fig. 4 schematically depicts a snapshot of the process according to the present invention. Fig. 5 schematically shows various stages relating to folding. Detailed description

The present invention relates to the attachment of strips to a moving web, whereby the strip is applied adjacent to a predominantly CD oriented separation line, such as a cut or a slit in the web. This separation line is at an angled orientation to the longitudinally extending side margins or centre line of the web, and the applied strip is at an angled, typically right angled orientation to this separation line and may optionally be folded around this separation line. The present invention may be applied in a wide array of converting webs, such as in the manufacturing of individual articles, such as when pouches or sachets are equipped with adhesive closure strips, optionally as re-closeable strips. The present invention is particularly suitable in the manufacturing of disposable articles, such as diapers.

Generally, the term "web" relates to any material which is essentially endless or continuous in one direction (generally denoted as "x-direction" or "machine direction"). Webs are often, but not necessarily, stored, supplied or used in roll form and thusly also sometimes denoted "roll goods". Whilst these are then not "endless" in the strict sense of the word, their extension in this x-direction is significantly larger than in any other direction. By combining consecutive rolls or other batches, ("splicing") such webs can be considered "endless" for all practical purposes. Webs may be transported in a "batch" form, such as when a roll thereof is shipped, or they may follow a "web path", such as when the webs are unwound from rolls, as described hereinafter.

Webs may have an essentially uniform thickness (herein denoted as "z-direction", and also constant width (herein denoted as "y-direction") along the x-directional length. Webs may be of essentially uniform composition, they can be mixtures of materials, they can be composites of materials such as being layered (different materials arranged in a juxtaposed position in the z-direction) and/or can comprise stripes of different materials or materials having different or varying properties (i.e. arranged in a juxtaposed position in the y-direction). Typical examples for webs are - without implying any limitation - plastic films or foils, textiles, non-wovens, nets, scrims, paper, or cartons.

Webs may be non-uniform in any direction. Typical examples for such webs are disposable articles, such as diapers, during their manufacturing. Such articles may be composed of a number of other materials, including other precursor webs, such as non- wovens or films, or cut pieces of such webs, or including separated items, such as absorbent cores which may comprise particulate material. During the manufacturing, various such elements may already be combined to form pre-forms of the article, which are still connected to each other, i.e. still forming a web of an essentially continuous series of pre-forms.

During the converting of the webs, these travel along a manufacturing machine direction with a web speed. The web speed may vary significantly depending on the particular situation, but even for relative complex articles like disposable absorbent articles the web speed may be over 100 m/min or even over 1000 m/min.

During converting the webs run over web support means, such as belt systems, drums, rolls, turrets and the like, all well known to a person skilled in the art. The webs may run over a series of web support means, and may be partly unsupported there between, and may also, at least partially, be turned upside down. However, within the context of the present description, it is assumed, that the web is supported by web support means and that during the converting step according to the present invention the orientation of the major areas respectively surfaces of the web is maintained. A skilled person will, however, readily apply the teaching of the present invention also to a situation, wherein the orientation of the surfaces is changed.

Web orientation refers to the movement direction of the web, but also to the orientation of the surfaces of the web. Within the present description the web overlays a web support means such that its first surface is oriented away from the web support means, whilst its opposite surface is oriented towards the web support means and may be in direct contact therewith. The web may lay over the web support means along the direction of gravity, but the skilled person will readily recognize, that also in an "upside down" process the first surface will be oriented away from the web support means, even if it were now below it in terms of up and down along the direction of gravity. Similarly, if the web support means would be a rotating drum or turret, as also well known in the art, the first surface would be oriented away from this turret, even if during the rotation the upward and downward orientation may change relative to gravity.

The web overlays the web support means with a major surface. When a flat, unfolded web overlays a web support means such as a belt, this major surface corresponds to the full opposite surface. Even if - as may be often the case during the manufacturing - a longitudinal wrinkle or fold is formed such as due to web tensions, the major opposite surface of the web is still oriented towards the web support means, even if not all areas of this surface are in contact therewith.

A web may also be purposely folded such as along a longitudinal fold line. For example, a region along the longitudinal side margins of the web may be folded by 180° inwardly, i.e. towards the longitudinal centre line of the web. When looking towards the web support means, the unfolded regions would show the first surface, whilst in the overfolded regions, the opposite surface faces upwardly. Nonetheless, the web would still exhibit its major first surface oriented away from the web support means.

A web may also be completely folded along a longitudinal fold line, e.g. when a longitudinal side margin of a precursor web is folded over along a longitudinally extending fold line. If such a web would be subjected to the step of applying a strip according to the present invention, the definition of the first and opposite web surface is considered to be made just prior to the execution of the presently described process. This may be exemplified when considering a disposable article such as a diaper. Such an article is typically described as having a topsheet surface, which is intended to be oriented towards a wearer during use, and an opposite backsheet surface, which is intended to be oriented towards the clothing of a wearer during use. Such an article exhibits a longitudinal orientation on the wearer, i.e. a front and rear waist portion connected by a mid or crotch portion.

If such an article is produced in a so called "CD-process", these portions are positioned cross-directionally relative to each other on the manufacturing line. During the manufacturing, webs such as topsheet and backsheet are typically combined flat, such that the pre-form of the article is also essentially flat, and thus the backsheet may overlay the web support means and the topsheet may face away from the web support means. When such a flat pre-form of an article is folded along a longitudinal centre line of the machine, which corresponds to a cross-directional centre line of the article, the topsheet will be folded onto itself, and the total outer surface will be backsheet.

The process according to the present invention may be executed both to the unfolded web and to the folded web. In the first instance, the "first surface" as used in the present description, would be made up of the topsheet, and the opposite surface of the backsheet. In the second instance, i.e. after the longitudinal folding, both the first surface and the opposite surface would be made up of the backsheet.

Within the present description, the term "folding" is used context-dependently, as is further described in Fig. 5. The general meaning of "folding" refers to the bending of a material along a fold line 1060 around a folding angle. For a flat, unfolded web material 1000 the folding angle 1061 is considered to be 180°. For a material 1000', which has been "upfolded", the angle 106 is less than 180°, here shown as 90°. A material 1000" is "overfolded", when its folding angle 1061 " is very low, i.e. approaching 0°, and the material is in an essentially layered arrangement. "Backfolding" refers to the step of opening an overfolded or an upfolded material by increasing the folding angle, as indicated by the backfolding direction 1063, optionally towards an unfolded, i.e. flat, arrangement.

The present invention relates to applying a strip of material to a moving web whereby not all areas of the strip may be in contact with the same surface of the web.

A strip of material is considered to be any material exhibiting a length and a width dimension which are typically much larger than its thickness dimension. Typically, such a strip will be smaller than the web to which it is attached. Often, though not necessarily, the strip is a cut piece of a further web material as described in the above. The strip may be a unitary material or may be a composite. For example, two or more webs may be combined in a layered arrangement. A strip may be a combination of materials, such as webs, in a side-by-side arrangement or partially overlapping. A strip useful for the present invention will be flexible, so as to run smoothly through the process. Typically, and in particular for the application in absorbent articles, the term "flexible" refers to materials that are compliant and that will readily conform to the general shape and contours of the human body.

The strip may have particular functional properties, such as adhesion properties, which may be different on the opposite surfaces of the strip, or which may vary across one surface of the strip.

A non-limiting example for a strip may be an adhesive closure tape, such as may be applied to bags or sachets. In such an application, the strip may be a tape with an adhesive coating on one of its surfaces, which may be applied and attached to the web forming the bag or sachet. Another example for a strip may be a closure tape for an absorbent article, such as a diaper. Such a closure tape may also have an adhesive coating on one surface, and the strip may be applied such that a first portion of the strip is firmly attached to one portion of the web, which may correspond to a rear portion of the diaper, whilst a second portion may optionally be attached during the manufacturing and may optionally be repositioned by a user such as to close the diaper for its use or to adjust fit. In this case, the two portions of the strip may have varying adhesion properties and may be composed of several layers. Alternatively, at least one of the portions may comprise so called mechanical fastening elements, as well known in the diaper art. In yet a further alternative, a strip may be applied to the web in a first step, and affixed by a separate step, which may be compressing the strip to the web, or which may be any other bonding, including permanent bonding like welding etc..

According to one execution of the present invention, the strip is applied to the web such that after having executed the present invention, a first portion of the strip will be applied to the first surface, and a second portion to the opposite surface, and the strip will be folded around a margin or edge of the web.

Thus in the example of a simple two layer web made up of a topsheet and a backsheet, one portion of the strip is applied to a first surface, say the topsheet, and another portion to an opposite surface, say the backsheet, which may also overlay a web support means. Such a construction is schematically shown in Fig 1. The strip is shown as a tape composite 1100, which may suitably be used as a tape in a diaper construction. It comprises a fastening tape 1110, which comprises an adhesive coating 1117 on one surface and a backing 1114. A first portionl 112 of the strip is uncovered, whilst a second portion 1118 is covered by a release tape 1120. The backing of the release tape 1127 is attached to the second portion whilst the adhesive of the release tape 1124 is shown uncovered. Such a tape may be cut from an essentially endless roll, such that Fig. 1A shows the cross-sectional view of the material. By using the process of the present invention, the composite can be applied to a web. The web 1000 as shown in Fig. IB has a first surface 1020 and an opposite surface 1030. The tape composite is applied to the web with its first portion 1112 to the opposite surface and folded around the web margin 1010 such that the second portion 1118 with the release tape 1120 is applied to the first surface 1020. As indicated in Fig. 1C, a user may separate second portion 1118 from the release tape 1120 and close the diaper.

A similar, and often preferred construction is schematically depicted in Fig. 2, showing a so called and also well known "Y-bond", also in a configuration as it may be supplied (Fig. 2A), as it may be applied such as by the process according to the present invention (Fig. 2B) and as may be used by a user (Fig. 2C). The "Y-bond" 1140 will distribute the pull forces to both surfaces of the web, or to both web components, if the receiving web were a layered laminate. The end fold tab 1130 or a glue free zone of the fastening tape in the same position will ease the opening by the user.

In the example of a two layer web material being longitudinally folded, one portion of the strip may be applied to the topsheet as first surface, and a second portion may be applied to the backsheet.

It is an important feature of the present invention, that the strip is applied to a predominantly cross-directionally extending margin of the web, whilst this is moving in its machine direction. Optionally, the strip may be folded around this margin.

When an article is produced such that the longitudinal orientation of the article or its preform forming the web is parallel to the machine direction of the web, tapes can be readily applied at the longitudinally extending side margins of the web by simple cutting, application and folding, such as by folding bars.

However, when the longitudinal orientation of articles is essentially perpendicular to the machine direction of the web, this simple tape application is not possible. Presently, the pre-forms of the articles are typically cut into the individual articles and rotated such that the tapes can be applied as described above.

The present invention allows applying strips like such tapes without the need for this additional rotating step. To this end, a separation line is applied to the web, which may be readily visible or a thought line. The separation line starts at a first longitudinally oriented side margin of the web, and runs away there from, in the direction towards the longitudinal centre line. The separation line will be predominantly CD oriented, i.e. will run at an angle of 90° +/- less than 45° relative to the longitudinal centerline. Often, a 90° angle is preferred. In many executions, a straight separation line will be preferred for ease of application, although it may also be in a curved configuration, whereby the orientation is then determined by connecting the intersection with the side margin and the endpoint of the line. The web will be severed along the separation line up to a severing end point. In a first embodiment, the severing is executed concurrently with the application of the separation line. In a particular execution, the separation line may be a cross-directionally oriented straight cut line. The separation line may terminate, i.e. it will be not separate the web completely, such that the web is still continuous after the separation line is applied and severed. In another embodiment, the separation line may also be applied as an incomplete severing line, such as by a sequence of smaller cuts or perforations. The uncut sections may then be completely severed or opened at a later step by a separation means, such as when the folding means is moving along the separation line, as described herein below. Alternatively, the severing and the separation may be performed concurrently with the moving of the folding means.

For the purpose of the present description, the regions adjacent to the separation line are referred to as forward (front) or rearward (rear) folding region. The folding region(s) having an essentially triangular shape delimited by the longitudinally extending side margins, the separation line portion extending from the longitudinally extending side margins up to the severing endpoint, and a resulting folding line. Often, the folding lines will have an orientation of between 40° and 50° relative to the longitudinal centre line of the web.

When the separation line is cross-directionally oriented, and the front and rearward web regions are folded around fold lines with an orientation of about 45° angled relative to the web machine direction before receiving the tape strips, the orientation of these strips will undergo an about 90° turn relative to the machine direction of the web when the front and rearward regions are folded back to their original position.

In a particular embodiment, the separation line is cut into the web by a separation or cutting means, such as a rotating knife, which may be positioned relatively stationary to the web. This can be achieved by affixing the rotating knife to the web support means. Alternatively, the separation means may have its own frame and drive mechanism and it may move with a translatory speed adjusted to the web speed.

In one embodiment, just one strip may be applied to either the front or the rear regions adjacent to one separation line. In a further, often preferred embodiment, each one strip will be applied to the front and the rear region respectively. Such an application will be particularly suitable, when an article to be worn on the lower torso of a wearer, such as a diaper, shall be equipped with one strip on each of its lateral sides. Similarly, two separation lines may be provided starting from each of the laterally extending side margins, which would - in the case of diapers - provide two tape strips at each lateral side, either in the front, or in the back region.

The method according to the present invention employs a folding means. An exemplary execution of such a folding means is schematically depicted in a top view in Fig. 3. Such a folding means 2000 comprises one or more guide means 2020. As shown the guide means 2020 are executed as guide plates, which make it suitable for applying each one strip to the front and rear folding regions of one separation line. The surfaces of the guide plates that face away from the web support means 3000 are preferably adapted so as to allow any adhesive of the strip, if present, not to adhere thereto. This can be reached by conventional means, such as - without any limitation - ceramic, silicon, or Teflon® coatings. The guide plates may be dimensioned to allow at least a part of the second portion of the strip to be positioned thereon so as to prevent sticking of this portion to the web. The plates have a front edge 2042 and are connected via a frame 2030 to a drive means connection 2050 and a drive means (not shown). The drive means allows a movement along a folding means axis 2010 at a controlled and variable speed.

The folding means may comprise a further drive means or a connection to the web support means, such that the folding means can remain registered with the web, in particular to the separation line respectively the front and rear folding regions.

Fig. 3 further shows a separation means 2100, which may also be connected to the web support means or its frame or which may be translatorily moveable so as to stay in registry with the web. The separation means is shown as a rotating knife 2110 connected to a rotating drive means 2120. In a particular embodiment the separation means can be integral with a downfolding means such as when the separation is achieved by preparing an incomplete separation, such as by a perforation, which is then opened by the folding means movement, or whe the separatin is executed concurrently with the movement of the folding means.

Fig. 3 shows further a particular execution for an edge upfolding means. As will be described in more detail herein below, the front and rear folding regions of the web will first be up folded out of the plane of the major first web surface to then be overfolded by the folding means to lay over the first major surface. The upfolding may be eased by an upfolding means 2200, here shown as triangular upfolding regions 2210 corresponding to the front and rear folding regions of the web and delimited by an upfolding demarcation line 2250. The upfolding region may be an elevated plate such that when in the lower adjacent region of the web support means the web is pulled down e.g. by vacuum suction 2230, the web in the front and rear folding regions will fold upwardly due to geometric constraints of the elevated plate 2210. Alternatively or in addition, the upfolding region may be equipped with other mechanical or pneumatic means, e.g. air blow nozzles 2220, also upfolding the web to a certain extent.

It should be noted, that this upfolding does not need to be complete, as the folding means will perfom the further folding. The upfolding is just to help, support or initiate the further folding through the folding means.

The front and rear upfolding regions may be separated by a slit 2215, e.g. to allow the rotating knife to pass through.

After having described the key elements used in the description of the process, the following addresses the individual process steps, some of which not necessarily have to be executed in the described order or may be executed concurrently with others.

a) As a first step, a web material as described in the above is provided and transported on a web support means along its machine direction at a web speed. The web material has a longitudinal centreline, a first and a second longitudinally extending side margin, a major first web surface and a major second, opposite web surface, which is oriented towards the web support means.

b) Whilst the web is moving, one or more separation lines are applied to this web, intersecting at least the first longitudinally extending side margin, and being predominantly CD-oriented. A separation line may be a straight cut line extending away from a longitudinally extending side margin in the direction towards the longitudinal web centreline.

c) Concurrently to step b) or thereafter, the web is being severed along the separation line from the first longitudinally extending side margin towards a severing endpoint whilst leaving the web essentially continuous. The separation line defines a front and a rear folding region extending forwardly respectively rearwardly of the separation line towards the folding line.

d) As the next step, the front and rear folding regions are upfolded away from the web support means along a front and/or a rear folding line. The folding region(s) have an essentially triangular shape delimited by the longitudinally extending side margins, the separation line portion extending from the longitudinally extending side margins up to the severing endpoint, and a resulting folding line. The upfolding may be achieved by using the upfolding means as described above. Thus the upfolding can be performed pneumatically by varying air suction or blowing in the front and rear web regions compared to the surrounding regions, or geometric-mechanically by inducing upfolding, e.g. by positioning an elevated fold support plate on the web support means such that the web fold regions overlay the elevated fold support plate. The upfolding may also be induced by other means such as electrostatic means, or by a combination of various means. In a particular embodiment, the upfolding is performed along folding lines positioned at an angle of about 45° relative to the longitudinal centre line.

e) Once the front and rear web regions are at least slightly upfolded, the folding means is moved translatorily parallel to the separation line such that the front edges 2042 overfolds the front and rear folding regions to lay flat on the adjacent unfolded web regions. The folding means is moved further along its axis, such that a part of the overfolded edge is not covered by the folding means.

f) The strip which is to be applied to the web is provided. The strip may be irregularly shaped, and may be provided as individual pieces. Preferably, the strip is provided by cutting strip pieces from an essentially endless strip web, such as provided on a roll. In a preferred execution, the strip has a rectangular shape. In a particular execution, the strip is provided as a cut piece of a strip web, whereby the MD-direction of the strip web corresponds to the MD direction of the web material to which the strip is applied. In this execution, the properties may be readily varied across the width of the strip web, and hence of the strip.

Across the width of the strip as applied it has a first and a second portion. Further portions may be laterally outside of or between the first and second portion. Typically, the portions have different properties, such as different adhesion or release properties. The strip exhibits a major first and a major second, opposite surface, for the purpose of the description the first surface having adhesive properties and the second opposite non- adhesive, e.g. adapted such that a wound up roll of strip web is not blocking, i.e. two adjacent layers on the roll can be readily separated. The term "major" denotes, that for example the side margins of the strip may be folded over so as to create end tabs 1130 as shown in Fig. 2.

g) The strip is further positioned relative to the web and applied thereto, such that the first strip portion overlays with its first surface the overfolded web fold region and is attached thereto such that its second surface is oriented towards the same direction as the major first surface of the web. The second strip portion extends outwardly, such as by overlaying the guide plate of the folding means. Due to the non-adhesive properties of the plate surface the second strip portion is not attached thereto but loosely lays on it.

This stage of the process is schematically exhibited in Fig. 4, showing the same equipment as Fig. 3, and additionally web 1000 and strip 1100. The major first websurface 1020 is oriented towards the viewer, the opposite major surface towards the web support means. A part of this opposite surface 1030 (here shown hatched) can be seen in the overfolded front and rear folding regions next to the fold line 1060. A first portion of the strip 1112 overlays the overfolded region. It may be attached merely by the adhesive properties of the strip, though this attachment may be strengthened such as by pressing it by appropriate means to the web. A second portion of the strip 1118 may either be attached to the first major surface, or it may overlay the guide means plate 2020 without adhering thereto.

Optionally, the up folding step d) may comprise one or more of the following sub-steps:

(m) varying the air suction or blowing adjacent to the web fold lines;

(n) inducing upfolding mechanically by positioning an elevated fold support plate on the web support means such that the web fold regions overlay the elevated fold support plate, whereby the margins of the plate correspond to the web fold lines; and

(n) varying electrostatic forces adjacent to the web fold lines.

For certain applications, the strip may remain as such, and the process may be finished by repositioning the folding means so as to enable the repetition of the process.

h) Optionally, the second strip portion may be permanently or releasably attached to the major first web surface.

i) Optionally, and often preferably, the strip may be folded around the separation line. To this end, the folding means is retracted along its axis, whereby the overfolded front and rear folding regions of the web with the strip attached thereto are backfolded by the rear edges of the guide means 2048. By his backfolding, orientation of the strip is changed. If the separation line is oriented in CD, and the strip is applied parallel thereto, it will be oriented parallel to the MD of the web after the backfolding.

j) Whilst the front and rear folding regions of the web can be completely and readily backfolded with the first portion of the strip attached thereto, the second portion of the strip may be overfolded in the next step. After the backfolding of the front and rear folding regions with the first portions of the strip attached thereto, the second portions of the strip will essentially stand out of the plane of the web, either by the mere presence of an adjacent strip, alternatively (e.g. in the case of applying only one strip to the regions of a separation line) or additionally by a strip support means. Such a strip support means can be integral with - or even identical to - the separation means. If this separation means is executed as a rotating cut blade, which (according to step b) is moved through the slit 2215 it can be rotated to a position such that the strips abut against the blade.

Once the backfolding of the second portion is limited, this portion can be overfolded to overlay the first surface 1020 in the front or rear folding region. To this end, a strip overfold means can be applied. In a first execution, the separation blade may be executed such that it comprises hinged folding plates, which are activated to overfold the second strip portion. In a second alternative or additional execution, the separation means can further be modified to include such a strip overfold means, such as by comprising air blow holes, which at least initiate the folding. Optionally a further compression means can complete the overfolding.

After having executed these steps, the strip application is completed, and a tape strip, as shown in Fig. 1A and 2A has been applied to a web material and folded around a web material edge as shown in Fig. IB and 2B.

In a further aspect, the present invention is an apparatus for applying strips of material to a moving web, which comprises: a) web supply means;

b) web support means for moving the web along its machine direction;

g) a web region overfolding means for folding regions of the web adjacent to the separation line; h) a strip supply means;

i) a strip application means;

j) a web regions backfolding means for folding the web region back; k) a strip overfolding means.

The separation means d) may be integral with one or more of the following:

(i) strip support means;

(ii) strip overfolding means.

Claims

1. A method for attaching a strip of material to a web, said web moving along its machine direction, thereby defining a longitudinal direction of the web, said method comprising the steps of

a) providing a web and moving said web on a web support means along its machine direction, said web exhibiting a longitudinal centreline and a first and a second longitudinally extending side margin, a major first web surface, and a major opposite web surface, which is oriented towards said web support means;

b) applying a separation line to said web

intersecting at least said first longitudinally extending side margin,

and being predominantly CD-oriented;

c) severing said web along said separation line from said first longitudinally extending side margin towards a severing endpoint whilst leaving the web essentially continuous; d) upfolding a forward and/or a rearward folding region from said web support means, said folding region(s) having an essentially triangular shape delimited by

said longitudinally extending side margins,

said separation line portion extending from said longitudinally extending side margins up to said severing endpoint, and

a resulting folding line;

e) moving a folding means along said separation line, optionally concurrently severing said web according to step c), towards said severing end point, thereby overfolding said folding region(s);

f) providing at least one strip of material having a first and a second strip surface and comprising a first and a second strip portion positioned adjacently along the width direction of said strip;

g) positioning said strip such that said strip width is oriented essentially parallel to said separation line, and such that said first strip portion overlays said overfolded web region and is attached with its first surface thereto, whilst said second strip portion protrudes over said overfolded web region whilst remaining essentially unattached to said major first web surface.

2. A method according to claim 1, further comprising the step of

h) attaching said second strip portion to said major first web surface.

3. A method according to claim 1, further comprising the step of i) backfolding said overfolded web region with said strip by back-moving said folding means along said separation line, thereby changing the orientation of said strip.

4. A method according to any of the preceding claims, further comprising the step of j) overfolding said strip such that said second strip portion is folded onto said major first web surface, and optionally attaching said second strip portion to said major first web surface.

5. A method according to any of the preceding claims, whereby said up folding step e) comprises one or more of the following steps:

(m) varying the air suction or blowing adjacent to the web fold lines;

(n) inducing upfolding mechanically by positioning an elevated fold support plate on said web support means such that the web fold regions overlay said elevated fold support plate, whereby the margins of said plate correspond to the web fold lines; (n) varying electrostatic forces adjacent to the web fold lines.

6. A method according to any of the preceding claims, wherein said folding lines are between 40° and 50° relative to said longitudinal centre line of said web.

7. A method according to any of the preceding claims, wherein said folding means comprises a pair of folding plates, optionally having anti-adhesion surfaces.

8. A method according to any of the preceding claims, wherein said web and/or said strip is a composite material.

9. A method according to any of the preceding claims, wherein said first and said second portion of said strip exhibit different attachment strength properties.

10. A method according to any of the preceding claims, wherein said strip comprises adhesive or mechanical fastening elements.

11. A method according to any of the preceding claims, wherein said longitudinally extending side margins of said web are formed by overfolding side portions of a wider precursor web along one or more longitudinally extending precursor web folding lines.

12. A method according to any of the preceding claims in the manufacturing of a garment for being worn on the lower torso of a human wearer comprising a front, mid and rear portion corresponding to a front waist, crotch, and rear waist orientation during use, hereby defining a length orientation of the article, and wherein said length orientation of said article is essentially perpendicular (cross-directionally) to said web machine direction.

13 A method according to claim 12 in the manufacturing of a garment selected from the group of disposable or non-disposable absorbent articles, diapers, pants, adult incontinence articles, and feminine hygiene articles.

14. An apparatus for applying a strip to a moving web, said apparatus comprising a) web supply means;

b) web support means for moving said web along its machine direction;

c) web separation means for an incomplete separation of web regions along a separation line which has essentially a CD-orientation;

d) web severing means;

d) web region upfolding means

e) web region overfolding means for folding regions of the web adjacent to said separation line;

e) strip supply means;

f) strip application means;

g) web regions backfolding means for folding said web region back;

h) strip overfolding means

15. An apparatus according to claim 1, wherein said separation means is integral with one or more of the following:

(i) strip support means;

(ii) strip overfolding means.