Linerless Labels

Abstract

The present invention relates to a method for manufacturing a continuous linerless label web (100). The continuous linerless label web (100) comprises a face (110) having a first side (111) and a second side (112) and an alternating adhesive coating on the second side (112), wherein the method comprises providing the face (110) with a release coating disposed on the first side (111), providing an alternating continuous adhesive strip (121) on the second side (112) of the web (100), wherein the predetermined properties of the alternating continuous adhesive strip (121) are selected such that the number of strips in each customer roll (300) is one or more, the width of each strip is less than the width of each customer roll (300), and the position frequency is selected such that one oscillation cycle covers 0.1-10 machine roll (570) circumference lengths, and 1-100 customer roll (300) circumference lengths, the circumference length being defined as the length of the circumference of a complete roll. The present invention also relates to linerless label webs and linerless customer rolls.

Description

Technical Field

[0001] The present description relates to a method of making a linerless label web comprising a pressure sensitive adhesive. The present description also relates to a linerless label web comprising a pressure sensitive adhesive. Background Art

[0002] In industry, a wide variety of linerless labels are manufactured. Linerless labels can be used for a variety of purposes, such as printing on demand. However, conventional linerless labels are known to cause some problems. These problems may be due to the pressure sensitive adhesive being exposed without a protective release liner, resulting in tacky adhesive contamination, for example, onto the internal mechanisms of a printing press. In addition, applying the adhesive at high web speeds presents some manufacturing challenges.

[0003] Therefore, there is a need for improved linerless label products and improved methods for making label products. Successful production of linerless labels requires the successful and rapid production of larger machine rolls that can then be unrolled and slit into narrower and smaller customer rolls for use with a variety of linerless label printing equipment. Summary of the invention

[0004] One object of the present description is to provide a method of making a linerless label comprising a pressure sensitive adhesive. In addition, one object of the present description is to provide a linerless label comprising a pressure sensitive adhesive.

[0005] The various aspects of the invention are characterized by what is stated in the independent claims. Preferred embodiments are disclosed in the dependent claims. These and other embodiments are disclosed in the description and the drawings.

[0006] The linerless label includes a face having a first side and a second side. The first side of the face may be a top side of the face, and the second side of the face may be a bottom side of the face.

[0007] Furthermore, the first side of the linerless label may be a top side of the linerless label and the second side of the linerless label may be a bottom side of the linerless label.

[0008] The second side may include a pressure sensitive adhesive coating. The first side may include, for example, a release coating. The first side may have a printable surface. In one example, the linerless label includes a directly thermally printable coating on the first side.

[0009] The linerless label web may include or consist of:

[0010] -noodle,

[0011] - a release coating on a first side of the surface, and

[0012] A pressure-sensitive adhesive coating comprising at least one adhesive stripe of alternating position.

[0013] The linerless label web may be in the form of a machine roll. The machine roll may be unrolled and slit into smaller customer rolls. The linerless label web may also be referred to as a continuous linerless label web.

[0014] The linerless label web can be configured to be self-wound into a linerless machine roll, which can then be configured to be unwound and longitudinally slit and cut into narrower customer web lengths having a predetermined length and width. The customer web length can further be configured to be self-wound into a plurality of linerless customer rolls. The linerless label web includes an alternatingly positioned adhesive coating on the second side.

[0015] Thanks to the novel technical solution, a linerless label web is obtained which comprises, on the second side of the face, a pressure-sensitive adhesive coating comprising one or more adhesive strips and non-adhesive areas which are positioned alternately in a predetermined manner. This allows the linerless label web to be self-wound into larger machine rolls without suffering from telescoping effects which would cause significant complications or even prevent subsequent unwinding and longitudinal slitting into narrower customer rolls. The invention also provides significant benefits for smaller customer rolls.

[0016] The linerless label web may comprise at least one adhesive stripe of alternating position per customer roll.Thus, for each customer roll to be obtained from a machine roll, the machine roll may comprise at least one adhesive stripe of alternating position.

[0017] A method of making a continuous linerless label web may include the following steps:

[0018] - providing the face with a release coating arranged on a first side,

[0019] - providing a continuous adhesive stripe alternating in position on the second side of the web and having

[0020] - a predetermined number of strips (A) in the cross direction of the web,

[0021] - a predetermined width of the strip in the cross direction of the web (B),

[0022] - the frequency of the predetermined positions of the stripes in the longitudinal direction of the web (C), and

[0023] - The predetermined position amplitude (D) of the strips in the cross direction of the web.

[0024] The predetermined characteristics (A, B, C, D) of the alternating continuous adhesive strips may be selected such that

[0025] - the number of stripes in each client volume is one or more,

[0026] - The width of each strip is less than the width of a single customer volume, and

[0027] - The position frequency is chosen so that one oscillation period covers 0.1-10 circumference lengths of a machine roll and 1-100 circumference lengths of a customer roll, the circumference length being defined as the length of the circumference of a complete roll.

[0028] Due to this novel approach, telescoping issues that may pose challenges to the manufacturing method and reduce the productivity of the manufacturing process may be avoided.

[0029] The number of the adhesive strips of position alternation in the customer's roll is 1 or more than one, preferably equal to or more than 2, more preferably equal to or more than 4, most preferably equal to or more than 6. The number of adhesive strips is used to regulate the overall viscosity of the label and reduce the adhesive contamination in the linerless printing press in the customer's roll. In addition, the adhesive strips of more number provide the removability of the label and the ability to stick on uneven surfaces. In addition, preferably, the number of the adhesive strips of position alternation in the customer's roll is equal to or less than 15, more preferably equal to or less than 12, most preferably equal to or less than 10. The bars of more number do not provide any further benefit usually, but make the manufacture of the label web more complicated. Therefore, by the adhesive strips of appropriate number, the telescoping problem can also be avoided, and the customer's roll is obtained good characteristics simultaneously.

[0030] To avoid telescoping problems with the machine roll, the position frequency of the adhesive strips can be selected so that one oscillation cycle covers 0.1-10 perimeter lengths of the machine roll, the perimeter length being defined as the length of the perimeter of a complete roll. Furthermore, to avoid telescoping problems and improve the performance of the customer roll, the position frequency of the adhesive strips can be selected so that one oscillation cycle covers 1-100 perimeter lengths of the customer roll, the perimeter length being defined as the length of the perimeter of a complete roll.

[0031] Therefore, the position frequency of the adhesive strip can be selected so that one oscillation cycle covers equal to or greater than 0.1 perimeter lengths of the machine roll, more preferably covers equal to or greater than 0.4 perimeter lengths of the machine roll, and most preferably covers equal to or greater than 0.8 perimeter lengths of the machine roll, and the perimeter length is defined as the length of the periphery of the complete machine roll. In addition, preferably, the position frequency of the adhesive strip can be selected so that one oscillation cycle covers equal to or less than 10 perimeter lengths of the machine roll, more preferably covers equal to or less than 6 perimeter lengths of the machine roll, and most preferably covers equal to or less than 3 perimeter lengths of the machine roll, and the perimeter length is defined as the length of the periphery of the complete machine roll. Therefore, the telescoping problem of the machine roll can be avoided. In addition, the simplicity of the manufacturing process with such a position frequency can be improved.

[0032] In addition, the position frequency of adhesive strips can be selected so that one oscillation cycle covers 1 peripheral length equal to or greater than, more preferably covers 10 peripheral lengths equal to or greater than, most preferably covers 30 peripheral lengths equal to or greater than, and described peripheral length is defined as the length of the periphery of complete client's roll. In addition, the position frequency of adhesive strips can be selected so that one oscillation cycle covers 100 peripheral lengths equal to or less than, more preferably covers 80 peripheral lengths equal to or less than, most preferably covers 60 peripheral lengths equal to or less than, and described peripheral length is defined as the length of the periphery of complete client's roll. Therefore, the telescoping problem of client's roll can be avoided. In addition, some characteristics of client's roll can be improved.

[0033] When providing one or more position-alternating adhesive strips, the driving speed of the web can be in the range of 100m / min to 600m / min. Therefore, the speed of the web can approximately correspond to 1-10m / s. The speed can improve the simplicity of the coating process of the position-alternating adhesive strips.

[0034] The step of providing one or more alternating adhesive stripes may include the following steps:

[0035] - applying the adhesive to the face and then thermally drying the adhesive to form a pressure sensitive adhesive on the face, or

[0036] - applying the adhesive to the carrier material, thermally drying the adhesive to form a pressure-sensitive adhesive on the carrier material, and transferring the pressure-sensitive adhesive coating to the face.

[0037] The step of providing one or more alternating adhesive stripes may include the following steps:

[0038] - applying at least one continuous adhesive layer,

[0039] - removing at least 50% of the applied adhesive coating prior to drying by using an oscillating actuator in an oscillating manner to provide one or more alternating positions of adhesive stripes and adhesive-free areas.

[0040] The oscillating actuator may include a blade that may be used to remove at least some of the applied adhesive.

[0041] Therefore, the non-bonded area may contain 0.5-5.0 g / m 2 In some embodiments, the adhesive coating may be removed from the substrate and the adhesive coating may have a residual amount of adhesive coating within a range of 0.1 to 5%. Additionally or alternatively, the dry weight content of the adhesive coating after removal from the substrate may be 0.1-5% lower than the dry weight content of the adhesive coating applied to the substrate. Additionally or alternatively, the residence time between applying the adhesive coating and removing the adhesive coating may be 0.05 to 3 seconds.

[0042] In one embodiment, the step of providing one or more alternating adhesive stripes comprises:

[0043] - Local application of the adhesive coating by using an oscillating actuator to provide one or more alternating position adhesive stripes.

[0044] In this embodiment, the oscillating actuator preferably comprises a nozzle for applying the adhesive.

[0045] The alternating position adhesive stripes have a predetermined stripe width, a predetermined position amplitude, and a predetermined position frequency. The predetermined position frequency defines the wavelength of the stripes.

[0046] The width of each strip is less than the width of each customer roll. The width of each strip can be less than 0.5 times the width of each customer roll. The width of the strip can be equal to or less than the width of the adjacent non-adhesive area. Further, the width of each strip is preferably less than the width of the smallest single customer roll obtained from the machine roll. Therefore, the telescoping problem of the linerless label roll can be avoided while providing a good adhesion level for the pressure-sensitive label. The typical width of the linerless customer roll can be about 2 inches, for example 58 millimeters. In this case, the adhesive strip can have a width of 5 mm, separated by a 5 mm area without adhesive. As further explained below, the position amplitude of the strip can be, for example, 15 mm to 25 mm.

[0047] In addition, one or more position-alternating adhesive strips have a position amplitude. The position amplitude is determined in the cross-direction CD of the linerless label web. The position amplitude refers to the height of a wave (from the bottom of the strip to the top of the strip) determined in the cross-direction CD of the linerless label web. When measuring the position amplitude, each position of the position-alternating adhesive strip is determined from the middle of the adhesive strip.

[0048] The position amplitude can be selected so that it is within the range of 0.1 times to 1 times the width of each customer roll. The position amplitude is preferably equal to or greater than 0.1 times the width of each customer roll, more preferably equal to or greater than 0.2 times the width of each customer roll, and most preferably equal to or greater than 0.3 times the width of each customer roll. In addition, the position amplitude is preferably equal to or less than 1 times the width of each customer roll, more preferably equal to or less than 0.8 times the width of each customer roll, and most preferably equal to or less than 0.7 times the width of each customer roll, for example, within the range of 0.3 times to 0.7 times the width of the customer roll. Therefore, each customer roll has an adhesive coating over the entire length of the web, that is, the entire length of a customer roll has an adhesive coating on its surface. In addition, the position amplitude can help prevent the problem of telescoping by preventing the edges of the adhesive strips from "piling up" at the same position on the successive layers of the customer rolls. An additional technical advantage is that in a linerless printing press, the accumulation of adhesive residues (which may be more obvious at the edges of the adhesive strips) is distributed over a wider lateral area. Since the non-adhesive strips also have a high affinity for the adhesive (to obtain good adhesive anchoring), these areas also tend to clean up any loose adhesive residue inside the press.

[0049] Advantageously, the pressure sensitive adhesive comprises a water-based acrylic adhesive.

[0050] The total coverage of the adhesive coating may be equal to or less than 50% based on the total area of ​​the second side of the face. In addition, the total coverage of the pressure-sensitive adhesive coating may be equal to or greater than 10%, more preferably equal to or greater than 30%, and most preferably equal to or greater than 40%, based on the total area of ​​the second side of the face. Therefore, by using the total area of ​​adhesive and the alternating positions of the adhesive strips, the problem of telescoping of the linerless label roll can be avoided.

[0051] Thanks to the novel technical solution, a linerless label web is obtained, which comprises a pressure-sensitive adhesive coating on the second side of the face, the adhesive coating comprising one or more adhesive strips and non-adhesive areas, the positions of which are alternating in a predetermined manner. This allows the linerless label web to be self-wound into larger machine rolls without suffering from telescoping effects which would cause significant complications or even prevent subsequent unwinding and longitudinal slitting into narrower customer rolls. Preventing machine roll telescoping may be the main purpose of the invention. However, the invention may also provide significant benefits for smaller customer rolls, from avoiding telescoping to causing less adhesive contamination in linerless printing presses.

[0052] "Predetermined" should be understood as the adhesive strips of alternating positions being designed to provide benefits in both larger machine rolls as well as smaller customer rolls. Thus, the position alternation is specifically designed to provide benefits in both machine rolls and customer rolls.

[0053] "Position alternation" is further divided into two main parts here: the position frequency at which the adhesive stripe changes its position in the down-web direction and the position amplitude of the stripe in the cross-web direction. Together, these parameters define how fast and how much the adhesive stripe changes its position along the length of the web.

[0054] It should be noted that, in general, despite the position alternation, the coating thickness of the adhesive coating as well as the width of the adhesive stripe (and the adjacent adhesive or non-adhesive area) remain substantially constant over the length of the web. This makes it technically easier to implement the coating process and simplifies the curing / drying of the adhesive layer. For example, in a customer roll, a reduced and position-alternated adhesive coating can improve the functioning of an electric or manual cutter in a linerless printing press. Furthermore, in such an apparatus, a linerless label including an adhesive stripe may be more easily cut mechanically and leave less adhesive residue on the cutting blade or edge. In addition, using a water-based acrylic PSA may make it easier to achieve good anchoring on the substrate, in some cases even without using any additional primer.

[0055] Therefore, the novel technical solution may have one or more of the following advantages:

[0056] - the rolls in machine rolls or customer rolls have a smooth outer surface,

[0057] - No telescoping in the machine roll,

[0058] - No telescoping in the client volume,

[0059] - No adhesive bleeding / oozing, even if there is some adhesive at the edge of the customer's roll,

[0060] - reduced adhesive residues in any parts that come into contact with the web during manufacturing (coating, slitting) or end use (printing press),

[0061] - can slit any coil width without special adjustments, and

[0062] -Acrylic water-based adhesives can be environmentally friendly adhesives and can be used for example in food materials.

[0063] The waveforms produced by the predetermined selection of the position frequency and position amplitude of the bars can range from smoothly varying sinusoidal waveforms to more sharply varying almost step-changing waveforms. However, all can be characterized by having specific position dominant frequency and dominant amplitude properties.

[0064] The choice of the exact waveform is partly related to the technical practicality of applying the adhesive coating in a positional alternating manner. Applying a flowing liquid adhesive with tight coating thickness tolerances favors the choice of smoother waveforms, which are also technically easier to implement from the perspective of the required mechanical actuators. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In the following, the present invention will be described in more detail with reference to the accompanying drawings, in which:

[0066] Figure 1 The S of a linerless label (web) is shown by way of example. x , S y cross section,

[0067] Figures 2-3 show, by way of example, alternating adhesive stripes on the surface of a linerless label.

[0068] Figure 4a-4b By way of example, method steps according to an embodiment are shown.

[0069] Figure 5 Embodiments of the manufacturing method and apparatus are shown by way of example.

[0070] Figure 6 Details of a manufacturing method and apparatus according to one embodiment are shown by way of example.

[0071] Figure 7 Details of a manufacturing method and apparatus according to one embodiment are shown by way of example.

[0072] Figure 8 Details of a manufacturing method and apparatus according to one embodiment are shown by way of example.

[0073] Figure 9a -b shows photos of experimental tests,

[0074] Fig.10 One embodiment of the manufacturing method and apparatus is shown by way of example.

[0075] Fig.11 One embodiment of the manufacturing method and apparatus is shown by way of example, and

[0076] Fig.12a -b shows by example some of the guest volumes obtained from the machine volumes.

[0077] The accompanying drawings are schematic and are intended to illustrate the general principles of the disclosed technical solutions. Therefore, the illustrations in the accompanying drawings are not necessarily to scale or imply an exact layout of the system components. DETAILED DESCRIPTION

[0078] The technical solution is described in more detail below in conjunction with some implementation methods, but should not be construed as limiting.

[0079] In this specification, reference is made to the accompanying drawings in which the following reference numerals and symbols are used:

[0080] Sx,Sy,Sz 3D coordinates,

[0081] MD Machine Direction, First Direction,

[0082] CD Transverse, Secondary Direction,

[0083] Oscillating motion of AM actuator,

[0084] A1 position amplitude, that is, the height of a wave from the bottom to the peak,

[0085] P1 One cycle

[0086] WL wavelength, i.e. position wavelength,

[0087] WMR is the width of the machine roll,

[0088] WCR Width of the customer roll,

[0089] DMR machine roll diameter,

[0090] DCR diameter of the customer roll,

[0091] WA is the width of the adhesive in the adhesive strip,

[0092] 100 Linerless Label Web,

[0093] 110 noodles, noodle material,

[0094] 111 The first side, i.e. the top side,

[0095] 112 The second side, i.e. the bottom side,

[0096] 120 A pressure sensitive adhesive coating (PSA) comprising an adhesive strip,

[0097] 121 Adhesive coating,

[0098] 130 release coating, release coating layer,

[0099] 150 No bonding area,

[0100] 150a Non-adhesive area / strip on longitudinal edge,

[0101] 200 Linerless Labels, Labels (Products),

[0102] 300 Linerless Label Customer Roll,

[0103] 400 Oscillating Actuator,

[0104] 401 Set the surface material.

[0105] 402 Applying adhesive,

[0106] 402a applying adhesive to the surface,

[0107] 402b applying an adhesive to the carrier material,

[0108] 403 Set no-adhesive zone,

[0109] 404 Ensures the predetermined moisture level,

[0110] 405 Dry the adhesive,

[0111] 406 Transfer the adhesive to the surface,

[0112] 407 Winding the material into linerless rolls,

[0113] 560 Drying unit,

[0114] 561 Drying device,

[0115] 570 Linerless Label Machine Roll,

[0116] 580 coating unit for applying adhesive,

[0117] 580a Transfer roller of coating unit,

[0118] 580b Nozzle of coating unit,

[0119] 611,611a,611b Carrier material,

[0120] 611a belt,

[0121] 611b Tape Material,

[0122] 612 face uncoiler,

[0123] 650 Cooling cylinder,

[0124] 660 roller gap,

[0125] 690 Unit to remove adhesive,

[0126] 710 Carrier Unwinder,

[0127] 770 Linerless Label Web Winder,

[0128] 780 Carrier Rewinder, and

[0129] 870 Blocking gasket.

[0130] In this specification, the term "includes / comprising" may be used as an open term, but also includes the closed term "consisting of".

[0131] The temperature unit is expressed in degrees Celsius, equivalent to ℃.

[0132] Unless otherwise stated, percentage values ​​referring to the amount of material are percentages by weight (wt%). Unless expressly stated otherwise, all percentage values ​​refer to dry weight.

[0133] The term "web" refers to a continuous sheet of material. The web is typically processed by moving on rollers. Between processing stages, the web may be stored and / or transported in roll form.

[0134] In the present application, the term "linerless label web" refers to a continuous web including a face 110 and a pressure-sensitive adhesive 120, from which linerless labels 200, ie, individual labels, can be separated.

[0135] In this application, unless otherwise specified, the terms "label", "linerless label" and "adhesive label" refer to a single label product 200 separated from the linerless label web 100 to be applied to an article. The label 200 can be attached to the article by using an adhesive. Therefore, in this application, unless otherwise specified, the terms "label", "linerless label" and "adhesive label" refer to a product including a face 110 and a pressure-sensitive adhesive coating 120.

[0136] In this application, the term “linerless label (web)” refers to the label 200 and / or the linerless label web 100 .

[0137] The term "PSA" means pressure sensitive adhesive.

[0138] The term "machine direction" refers to the manufacturing direction MD of the web. The machine direction MD may also refer to the circumferential direction of the roll. In addition, the longitudinal and axial directions of the web are both referred to as the machine direction. In this application, the term "first direction" refers to the machine direction.

[0139] The terms "cross-machine direction", "cross-machine direction" and "cross direction" refer to a direction transverse to the machine direction. In the present application, the term "second direction" refers to the cross direction CD.

[0140] The term "face" refers to the base material of the label, also known as the face material or face material. If it is a plastic face material, it can also be called a face film.

[0141] In the present application, the term "adhesive layer" refers to a layer comprising alternating adhesive strips. Therefore, the adhesive layer comprises an area with adhesive and an area without adhesive. At least in the machine roll, the alternating adhesive strips can be continuous strips. The alternating adhesive strips have a predetermined width, a predetermined position frequency and a predetermined position amplitude. The adhesive layer can be composed of alternating adhesive strips.

[0142] The term "alternating position adhesive stripe" refers to a shaped adhesive stripe having a predetermined width, position frequency, and position amplitude.

[0143] The linerless label web has alternating positions of continuous adhesive strips having:

[0144] - a predetermined number of strips (A) in the transverse direction of the web 100,

[0145] - a predetermined width (B) of the strip in the transverse direction of the web 100,

[0146] - a frequency (C) of predetermined positions of the stripes in the longitudinal direction of the web 100, and

[0147] - the predetermined position amplitude (D) of the strips in the cross direction of the web 100 .

[0148] The predetermined number of strips in each customer roll 300 is preferably one or more. The predetermined width of each strip is preferably less than the width of each customer roll 300. The predetermined position frequency is preferably such that one oscillation cycle covers 0.1-10 circumference lengths of the machine roll and 1-100 circumference lengths of the customer roll 300, wherein the circumference length is defined as the length of the circumference of the complete roll. The predetermined position amplitude is preferably in the range of 0.1 to 1 times the width of the customer roll 300. By using all of these features, telescoping of the machine roll and the customer roll can be avoided. In addition, the ease of manufacturing process can be improved while avoiding telescoping problems. In addition, at least some characteristics of the customer roll 300 can be improved while avoiding telescoping problems.

[0149] The adhesive strips of the alternating positions are preferably in the form of sine waves, to increase the ease of manufacturing the linerless label web. Therefore, each adhesive strip of the alternating positions can have the shape of a sine wave. However, in one embodiment, the adhesive strips of the alternating positions can have other forms, such as square, triangle or some other forms. The adhesive strips of the alternating positions can have a waveform, wherein a single wave is repeated several times in the length direction (machine direction) of the linerless label web. This can improve the ease of production, and therefore can improve production efficiency.

[0150] Thus, "position alternation" means that the adhesive stripe changes its position in the longitudinal direction (ie, machine direction) of the web. The adhesive stripe is preferably a continuous stripe having a uniform or substantially uniform adhesive thickness and stripe width over the manufacturing length of the web.

[0151] The position alternation of the adhesive stripes of the web is predetermined. "Predetermined" in this context is to be understood as the position alternating adhesive stripes being designed to provide benefits both in larger machine rolls as well as in smaller customer rolls.

[0152] "Position alternation" is further defined using the following main components: "Position frequency" at which the adhesive stripe changes its position in the machine or longitudinal direction of the web and "Position amplitude" of the stripe in the cross-web direction. Together, these parameters define how quickly and to what extent the adhesive stripe changes its position along the length of the web.

[0153] The above-mentioned position alternation parameters are essentially predetermined and are derived from the physical dimensions of the machine roll and the customer roll and the parameters of the web manufacturing process. For the latter, one of the important parameters is the speed of the web during the adhesive coating process, in which the position alternating strips are also formed. These principles are explained below.

[0154] Typical machine roll diameters DMR in linerless web production are 500–1500 mm (0.5-1.5 m), although most rolls have a maximum diameter of about 1000 mm. This means that at the top of a full machine roll, there is a layer around the periphery of the roll that is about 1-5 meters long. A typical linerless customer roll 300 has a diameter DCR of 50–150 mm (0.05-0.15 m), making it about one-tenth smaller than the former, and reflecting a perimeter length of about 0.1-0.5 meters at the top of the roll layer. As will be appreciated, when looking at the perimeter length of an intermediate or nearly empty roll, these values ​​are close to those determined by the core size of the roll. These core diameters typically range from 50-200 mm for machine rolls and 5-20 mm for customer rolls.

[0155] During the adhesive coating process, the web may move at speeds of 100-600 meters per minute, translating to equivalent web speeds of approximately 1-10 m / s.

[0156] In the present invention, it has been noted that telescoping of the machine roll can be effectively avoided if the adhesive strips are applied with a predetermined position frequency and amplitude so that the adhesive strips have a certain position alternation along the length of the web and this alternation is derived from the dimensional characteristics of the machine roll and the customer roll.

[0157] According to the invention, the position frequency is chosen such that one oscillation period covers 0.1-10 circumference lengths of the machine roll and 1-100 circumference lengths of the customer roll 300, the circumference length being defined as the length of the circumference of a complete roll.

[0158] The above characteristics are derived from the fact that, when the adhesive coated web speed is in the range of 1-10 m / s, one oscillation cycle will be propagated to a suitable number of consecutive layers in the machine roll, which is low enough to prevent the machine roll from telescoping. If the machine roll periphery is about 1-5 meters long, then 0.1-10 periphery lengths of the roll correspond to an oscillation length of 0.1-50 meters. In addition, the frequency is low enough to be reflected on a customer roll with a diameter and periphery length about 10 times smaller.

[0159] The oscillation period according to the invention may be 0.1-10 circumference lengths, preferably 0.5-5 circumference lengths or even more preferably about 1 circumference length. Thus, as described above, telescoping of the machine roll can be prevented. A working embodiment comprises an oscillation period to cover a length of 3-4 meters on the machine roll.

[0160] The technical reason for expressing the oscillation period as roll circumference length rather than simply in meters is that the dimensions of the machine roll and the customer roll vary and both need to be considered when optimizing the position frequency. The position frequency further depends on the speed of the web during adhesive coating.

[0161] In addition, according to the present invention, the position amplitude is selected to be in the scope of 0.1-1 times of the width WCR of each customer roll 300. This can ensure that the entire length of a customer roll 300 has adhesive coating on its surface. In addition, at least one continuous adhesive strip can be matched in the width of a customer roll 300. According to one embodiment, the position amplitude is greater than the width of a single adhesive strip. This helps to further avoid in machine roll or customer roll 300, the edge of the adhesive strip in the continuous layer overlaps each other and forms a region where layer thickness has a significant gradient on a shorter lateral distance. Because internal pressure accumulates in the roll and causes telescoping, this gradient tends to promote the layers in sequence laterally.

[0162] The number of strips within a single customer roll 300 may preferably be 2-6, such as in the range of 3 to 4. This may help prevent telescoping while improving some properties of the customer roll 300. Increasing the number of strips in a single customer roll 300 beyond 10 does not provide any further significant benefit and only complicates manufacturing.

[0163] In the following, the different components of the linerless label web are described in more detail.

[0164] noodle

[0165] The surface 110 may have a single layer structure, or it may have a multilayer structure including two or more layers. The surface 110 is a layer adhered to the surface of the article by an adhesive coating. The surface 110 includes a first side 111 and a second side 112. The second side 112 is an adhesive side, and the first side 111 may be a printed side. The surface 110 may include, for example, a printed matter that provides information and / or a visual effect.

[0166] In addition, the linerless label (web) 100, 200 may include additional layers, such as a top coating or cover laminate to protect the top surface of the label and / or the printed matter from friction or other external stresses. In addition, the primer can enhance the compatibility of adjacent layers or portions of the label, such as enhancing adhesion between layers. The face 110 may include one or more barrier layers to prevent chemical substances from migrating through the surface of the first side 111 of the face or the surface of the second side 112 of the face, or other interfaces of the linerless label (web) 100, 200.

[0167] The linerless label (web) 100, 200 comprising the face 110, the print layer and the pressure sensitive adhesive coating 120 may be referred to as a printed label. In one embodiment, the first side 111 of the linerless label (web) may be printed by using heat.

[0168] The surface 110 may include paper containing natural fibers as its main raw material. Natural fibers refer to any plant material that does not contain cellulose. The natural fibers can be wood-based. The wood-based natural fibers can come from softwood trees, such as spruce, pine, fir, larch, Douglas fir or hemlock, and / or from hardwood trees, such as birch, aspen, poplar, alder, eucalyptus or acacia, or from a mixture of softwood and hardwood. The surface 110 may include cellulose fibers from hardwood and softwood. A mixture of hardwood and softwood can be used to increase the internal bonding strength of the surface 110.

[0169] Paper suitable for the surface 110 is usually so-called wood-free paper. Wood-free refers to chemical pulp, such as Kraft pulp. According to one embodiment, due to the high quality requirements of the surface, the pulp used to make the surface does not contain any kind of mechanical pulp. Therefore, the surface 110 can be a wood-free paper containing fibers (e.g., fibers from softwood and / or hardwood).

[0170] The face 110 may include, for example, at least one filler selected from the group consisting of clay, calcined clay, kaolin, natural heavy calcium carbonate, precipitated calcium carbonate, talc, calcium sulfate, and titanium dioxide. Based on the total weight of the face 110, the total amount of filler in the face 110 is preferably less than 10% by weight, more preferably less than 5% by weight, and most preferably less than 3% by weight, such as between 0.5% by weight and 5% by weight, or between 0% by weight and 3% by weight. Fillers can reduce the cost of manufactured products. However, mineral fillers may also reduce the strength characteristics of the face 110. In addition, if the face contains too much mineral filler, some characteristics of the face 110 may be impaired. Therefore, in one example, the face 110 does not contain the mineral filler.

[0171] Side 110 may include paper coated with one or more coatings. For coated paper, 1 to 12 g / m2 per side (on one or both sides) may be used. 2The coating may contain at least one pigment selected from the group consisting of clay, calcined clay, kaolin, natural heavy calcium carbonate, precipitated calcium carbonate, talc, calcium sulfate and titanium dioxide. In addition, the coating may contain a binder, such as starch and / or polyvinyl alcohol. The surface may also contain one or more additives.

[0172] The side 110 comprising paper may be calendered using a calender or supercalender to obtain a high density surface.

[0173] In addition to paper, or as a substitute for paper, surface 110 can include a film material, such as polyethylene (PE), polypropylene (PP) or biaxially oriented polypropylene (BOPP). In addition, other suitable materials, such as different types of polyesters, such as polyethylene terephthalate (PET) or polyethylene are also feasible.

[0174] The grammage of the surface 110 is preferably at least 50 g / m 2 , more preferably at least 60 g / m 2 In addition, the surface weight is preferably less than 85g / m 2 , more preferably equal to or less than 80g / m 2 For example, the weight can be 50g / m 2 Up to 82g / m 2 In the range of or 70g / m 2 Up to 80g / m 2 The gram weight can be measured according to standard ISO536.

[0175] In one embodiment, the linerless label is thermally printable, and the static sensitivity of face 110 may be less than 90°C, preferably in the range of 75°C to 90°C. Thus, if the linerless label is thermally printable, the static sensitivity may be high enough so that the product does not darken before printing (e.g., during shipping). However, the static sensitivity level is sensitive enough to allow thermal printing. In another embodiment, the linerless label is not thermally printable and may not have the static sensitivity described.

[0176] The optical density of surface 110 can be lower than 25 mJ / mm 2 , preferably less than 20mJ / mm 2 , more preferably less than 15mJ / mm 2 , for example at 10mJ / mm 2 Up to 15mJ / mm 2 In between. Too high an optical density may create challenges with the product. Also, a low optical density can speed up the linerless label press. Also, with a low enough optical density, linerless labels may not place too many demands on the press.

[0177] The face 110 may have a thickness (caliper) in the range of 60 μm to 85 μm measured according to ISO 534. If the face is too thin, the linerless label (web) 100, 200 may be difficult to handle. For example, if the face is very thin, the stiffness of the linerless label may be too low, resulting in the linerless label being too loose. Therefore, the linerless label (web) may be difficult to manufacture and / or may cause problems when used with a printing press.

[0178] The top side of the linerless label may have a smoothness of at least in the range of 350 to 550 seconds (Beck), measured according to standard ISO 5627. For example, for use with a face comprising paper, if the paper is too rough, the life of the print head (if labels are to be printed) may be too much shortened.

[0179] The face may include a release layer, such as a silicon layer on top of the face. The release layer will make the linerless label (web) smooth, so the product may be more suitable for a printing press. Therefore, the face 110 can be pre-coated and the pre-coating layer can have the effect of providing smoothness to the substrate, i.e. the top surface of the face 110. The smoothness of the face 110 including paper has a positive effect on printing, such as by providing better resolution. The pre-coating layer may have a positive effect on the print quality. In one embodiment, the first side of the linerless label may have a smoothness equal to or greater than 1000 seconds (Beck), measured according to standard ISO5627.

[0180] The brightness of a linerless label (web) can be higher than 85% (R457) when measured according to standard ISO 2469. Therefore, a linerless label may look good. In addition, the high brightness may create contrast between symbols / letters. Therefore, if the lettering includes some machine-readable letters, these letters can be easily read due to the brightness.

[0181] The opacity of the linerless label may be higher than 80%, for example in the range of 80 to 90, when measured according to standard ISO 2471. Due to the opacity, the surface of the linerless label may not be too transparent to be readable by a machine or human eye.

[0182] When measured according to standard ISO1924 / 2, the tensile strength of the surface 110 and / or the linerless label (web) in the machine direction (i.e., the first direction) can be higher than 40 N / 15 mm, preferably higher than 45 N / 15 mm. Thus, the dimensional stability of the linerless label (web) can be improved, which can have a positive impact on the manufacturing process and printing process of the linerless label web.

[0183] When measured according to standard ISO1924 / 2, the tensile strength of the face 110 and / or the linerless label (web) in the transverse direction (i.e. the second direction) can be higher than 10N / 15mm. Due to said strength, the dimensional stability of the linerless label can be improved, which affects the manufacturing process and the printing process.

[0184] Surface 110 may have a FSC TM The paper substrate is made of a pulp of certified (mixed credit). Therefore, the facestock may include or consist of an environmentally friendly material. Therefore, the new linerless label (web) may be more environmentally friendly than some other types of facestock.

[0185] Adhesives

[0186] The label 200 and linerless label web 100 disclosed herein include adhesive coatings 120, 121, which include at least one adhesive strip of alternating positions. Pressure-sensitive adhesive coatings may also be referred to as self-adhesive coatings. Adhesive coatings 120, 121 including at least one adhesive strip of alternating positions include areas with adhesive and areas without adhesive. Adhesive areas include adhesive strips of alternating positions. Advantageously, the adhesive coating includes or is composed of adhesive strips of alternating positions, and the adhesive strips of alternating positions have no adhesive areas between adjacent adhesive strips. The adhesive coating may include one or more adhesive strips of alternating sinusoidal shapes, and therefore, the adhesive coating may include or be composed of at least one adhesive strip of alternating sinusoidal shapes.

[0187] Pressure sensitive adhesives may be permanent adhesives, or may be removable or repositionable, or even ultra-removable. In addition, pressure sensitive adhesives may have an operating temperature from ambient to freezing temperatures.

[0188] The maximum tack value of the pressure sensitive adhesive 120 measured on glass according to FINAT test method FTM9 may be equal to or greater than 3 N, more preferably equal to or greater than 4 N. Said value may be a suitable performance value for the pressure sensitive adhesive coating 120 of the linerless label (web) 100 , 200 .

[0189] The pressure-sensitive adhesive can be used for permanent linerless labels (webs) or removable linerless labels (webs). For removable linerless labels (webs), the maximum tack value measured on glass according to FINAT test method FTM9 is preferably between 3N and 6N. For permanent linerless labels (webs), the maximum tack value measured on glass according to FINAT test method FTM9 is preferably equal to or greater than 8N, more preferably equal to or greater than 10N, and most preferably equal to or greater than 17N.

[0190] In one embodiment, the maximum tack value of the pressure-sensitive adhesive 120 measured on glass according to FINAT test method FTM9 is equal to or less than 12 N, more preferably equal to or less than 6 N, and most preferably between 3 N and 6 N. Said value may be a particularly suitable performance value for the pressure-sensitive adhesive coating 120 of the linerless labels (webs) 100, 200 for fast food restaurants.

[0191] In another embodiment, the maximum tack value of the pressure sensitive adhesive 120 measured on glass according to FINAT test method FTM9 is equal to or greater than 8 N, more preferably equal to or greater than 10 N. Such values ​​may be particularly suitable performance values ​​for the pressure sensitive adhesive coating 120 of the linerless labels (webs) 100, 200 for industrial food or retail labeling.

[0192] In another embodiment, the maximum tack value of the pressure-sensitive adhesive 120 measured on glass according to FINAT test method FTM9 may be equal to or greater than 15 N, more preferably equal to or greater than 17 N. The value may be a particularly suitable performance value for the pressure-sensitive adhesive coating 120 of the linerless labels (webs) 100, 200 for logistics and warehouses.

[0193] The properties and characteristics of the PSAs used herein may vary depending on the end use of the label in question. Some properties are shown in Table 1 which shows some preferred values ​​and factors for adhesives for different end uses.

[0194] Table 1.

[0195]

[0196] In the context of this specification, the pressure sensitive adhesive is preferably a water-based PSA. Water-based adhesives may offer better sustainability, involving fewer fossil raw materials and fewer volatiles during manufacturing and end-use.

[0197] Furthermore, it may be easier to achieve a good level of anchoring on the face 110 disclosed herein with a water-based PSA even without using any additional primer. Thus, in one embodiment, the water-based pressure sensitive adhesive 120 is in direct contact with the face 110 without any other coating between the PSA and the face. Thus, in one embodiment, the adhesive exhibits sufficient anchoring to the face 110 and resistance to penetration of the face material, such that no primer is required. A flat adhesion profile over an extended dwell time and / or sufficient cohesion to resist flapping on a curved surface may be preferred. However, in one embodiment, the linerless label (web) includes the primer.

[0198] Going one step further, water-based adhesives can be designed to be approved for direct or indirect food contact (food safe), which is a requirement for certain food-related labeling end-use areas.

[0199] Pressure sensitive adhesives are suitable for high coating speeds. Preferably, the adhesive is applied at 10-30 g / m 2 A coating weight of 100% (dry coating weight) provides a coating without a reticulated structure.

[0200] Preferably, the water-based PSA is acrylic-based, that is, the adhesive is most preferably a water-based acrylic adhesive. Water-based acrylic PSA may have many advantages relative to other types of PSA. Water-based acrylic PSA can be environmentally friendly. In addition, due to the water-based acrylic adhesive, the viscosity of the product can be improved. In addition, compared with water-based acrylic adhesives, hot melt adhesives may be more likely to accumulate, such as accumulating in a cutting machine. Moreover, acrylic adhesives may have a longer open time, so if necessary, the linerless label (web) containing the water-based acrylic PSA can be removed after a few seconds or minutes. On the contrary, hot melt adhesives cannot be removed from the surface usually, even if attached to the wrong surface, it is also usually not removed therefrom. Therefore, the removability of water-based acrylic adhesives may be better than the removability of hot melt adhesives. In addition, the peeling value of acrylic adhesives is usually different from the peeling value of hot melt adhesives. Further, water-based acrylic adhesives may be the most preferred adhesive for the new technology solution.

[0201] Thus, the adhesive coating may include a water-based acrylic adhesive coating. The water-based acrylic adhesive coating may include, for example:

[0202] -butyl acrylate (BA), or

[0203] -2-hydroxyethyl acrylate (2EHA), or

[0204] -Butyl acrylate (BA) and 2-hydroxyethyl acrylate (2EHA).

[0205] The total content of butyl acrylate and / or 2-hydroxyethyl acrylate can be, for example, at least 20%, preferably at least 45%, or at least 58%, calculated on the dry weight of the water-based acrylic adhesive. A water-based acrylic adhesive containing butyl acrylate can be a permanent adhesive, while an adhesive containing 2-hydroxyethyl acrylate but not butyl acrylate can be a removable adhesive.

[0206] The water-based acrylic adhesive may be a tackified acrylic adhesive. Tackified acrylic adhesives can be used to provide a strong bond to a surface.

[0207] The adhesive coatings 120, 121 may be free of plasticizers. Adhesives free of plasticizers may be used, for example, on thermal papers (including economy grades) without problems with premature image development or image fading. This may have several advantages, as plasticizers may migrate into the product and cause problems. For example, food safety may be compromised.

[0208] The adhesive coating may comprise at least one surfactant.A surfactant is generally a compound that reduces the surface tension (or interfacial tension) between two liquids, between a gas and a liquid, or between a liquid and a solid.

[0209] In one embodiment, the adhesive coating may include at least one surfactant. The adhesive coating may include, for example, two different surfactants, such as an emulsifier and a wetting agent.

[0210] In one embodiment, the adhesive coating comprises a wetting agent. A wetting agent can be added to the adhesive coating to improve the coating process of the adhesive coating. The wetting agent can increase spreading and penetration properties by reducing surface tension. Wetting agents are known to those skilled in the art.

[0211] In one embodiment, the adhesive coating comprises silicone. The silicone in the adhesive coatings 120, 121 can improve the ease of cutting the label material, especially for on-demand linerless label printers. In addition, the silicone in the adhesive coatings 120, 121 can improve the self-winding properties of the linerless label web 100. Thus, due to the silicone in the adhesive coatings 120, 121, the linerless label web 100 can easily self-wind around itself without any tendency for adjacent layers of the linerless label web 100 to get in the way of each other. Thus, in one embodiment, the adhesive comprises:

[0212] - silicone components, such as silicone oil (polydimethylsiloxane), and

[0213] - emulsifiers, and

[0214] - Optionally, a wetting agent.

[0215] However, silicone is only an optional feature and the adhesive coating need not necessarily comprise said silicone.

[0216] In embodiments where the adhesive coating comprises the silicone, the pressure sensitive adhesive coating may comprise:

[0217] - an adhesive, wherein the amount of the adhesive may be in the range of 90 wt % to 99 wt %, calculated on the total dry weight of the pressure-sensitive adhesive coating, and

[0218] - Silicone additives, the amount of silicone additives being in the range of 1 wt. % to 6 wt. %, preferably in the range of 2 wt. % to 4 wt. %, calculated on the total dry weight of the pressure-sensitive adhesive coating.

[0219] Alternating adhesive strips

[0220] When label 200 is used, face 110 is adhered to another surface via adhesive coating 120. Thus, when label 200 is used, adhesive coating 120 adheres label 200 to the surface of the article. In this specification, adhesive coating includes one or more alternating adhesive stripes and adhesive-free areas.

[0221] refer to Figure 2a and 3a , the linerless labels (webs) 100, 200 may include adhesive strips of alternating positions and adhesive-free areas between the adhesive strips. For example, the adhesive-free areas 150, 150a in the adhesive layer may be used to prevent a linerless label printer from accumulating adhesive coatings onto the blades and rollers of the linerless label printer. The accumulation of the adhesive may result in a shortened service cycle of the printer. In addition, the adhesive-free areas may be environmentally friendly. Further, the adhesive-free areas may reduce the production cost of the linerless labels (webs).

[0222] However, adhesive strips pose some problems, such as Figure 9a Due to the telescoping, it is difficult to use adhesive strips on the linerless label web 100. However, due to the new technical solution with adhesive strips with alternating positions, the telescoping problem can be avoided while still obtaining the advantages of adhesive strips.

[0223] The pressure-sensitive adhesive layer 120 including the adhesive strips may have a thickness of 10 to 30 g / m 2 In addition, the target coating weight of the adhesive layer 120 including the adhesive strips may be 15 g / m 2 Up to 25g / m 2 In the range of (dry coating weight), most preferably in the range of 16g / m 2 Up to 21g / m 2 Preferably, in order to obtain a sufficiently good adhesive layer to adhere the linerless label to the surface of the article without being too expensive, the adhesive is an acrylic-based water-based PSA.

[0224] It should be noted that a certain coating thickness (coating weight) is required to obtain a water-based PSA as a uniform, defect-free layer on the face 110. The adhesive strip of the produced linerless label (web) 100, 200 can have a thickness of at least 10 μm, preferably at least 12 μm or at least 14 μm, most preferably equal to or greater than 16 μm. The coating weight of PSA needs to be high enough to fill the pores on the surface. Therefore, the thickness of PSA can depend on the surface to be coated. In addition, the amount of PSA needs to be high enough to adhere the label to the surface of the object. Advantageously, the thickness of the adhesive strip is equal to or less than 40 μm, preferably equal to or less than 30 μm, more preferably equal to or less than 25 μm, most preferably equal to or less than 20 μm. The thickness of the adhesive strip can be, for example, between 16 and 20 microns. Preferably, the thickness of the adhesive strip is kept constant in the machine direction and transverse direction of the strip, but due to manufacturing tolerances, there may be some small deviations from the target thickness value. Thus, an adhesive layer comprising an adhesive stripe which is good enough to adhere a linerless label to the surface of an article can be obtained without incurring much expense.

[0225] The pressure sensitive adhesive coating 120 may include one or more adhesive layers. If the PSA coating 120 includes more than one layer of adhesive, the adhesive coating may have improved smoothness. For example, if the first adhesive coating includes any pores, these pores may be filled with the second adhesive coating. This embodiment is particularly advantageous if the positionally alternating adhesive strips are obtained by removing some adhesive from a continuous adhesive layer in an oscillating manner.

[0226] If the adhesive stripe is formed by applying the adhesive in an oscillating manner, the manufacturing process may be more easily controlled if the adhesive coating comprises only one layer of adhesive. Thus, in this embodiment, the adhesive stripe comprises only one layer of adhesive.

[0227] As discussed, the use of adhesive strips brings new challenges to the manufacturing process of linerless labels (webs). The adhesive strips can cause telescoping problems between the machine roll and the customer roll. Telescoping may cause several problems at different stages of the process. Telescoping problems of the machine roll can cause problems with the slitter. In the slitter, the machine roll is slit into customer rolls. Due to the telescoping problem, the machine roll may be uneven, which may cause several problems with the slitter. Generally, the faster the start, the more severe the telescoping problem on the slitter. Due to the telescoping, the driving of the slitter may be more challenging and the driving speed of the slitter may be reduced. In addition, due to the telescoping problem, a considerable area of ​​the edge of the machine roll may not be used. In addition, if the driving speed of the slitter is reduced, the production efficiency of the slitter may be reduced. Therefore, the telescoping problem should be prevented instead of reducing the driving speed of the slitter.

[0228] Furthermore, for customer rolls, especially for large customer rolls having a great length, adhesive strips may also cause the telescoping problem. Therefore, conventionally, the use of adhesive strips has brought many challenges to the manufacturing process of linerless label rolls, which may hinder the use of adhesive strips.

[0229] The inventors of the present invention have surprisingly found a novel solution in which the telescoping problems caused by adhesive strips can be avoided by using adhesive strips with alternating positions.The novel solution can avoid at least some of the problems caused by adhesive strips.

[0230] The novel technical solution may include adhesive strips with alternating positions, which include adhesive-free areas between the adhesive strips. Thus, the adhesive strips 120, 121 may be in the form of adhesive strips with alternating positions. Figure 2a -b and 3a-b.

[0231] The position-alternating adhesive stripes may have a position amplitude A1 of the adhesive stripes in the cross direction of the linerless label (web) 100, 200. The position-alternating adhesive stripes may further have a position frequency (forming a position wavelength WL) in the machine direction of the linerless label (web) 100, 200. Thus, the position-alternating adhesive stripes may include a position wavelength WL and a position amplitude A1.

[0232] The position wavelength WL is the distance that one position wave of the adhesive stripe travels across the web to produce one complete cycle. A complete wave has a position amplitude A1.

[0233] In this application, one wavelength (i.e., from the bottom of the adhesive strip to the top of the adhesive strip, e.g. Figure 2b and 3b The maximum distance (measured in the cross direction CD) within the adhesive stripe is called the amplitude A1. Therefore, the amplitude A1 is the height of the wave measured in the cross direction CD. The position amplitude A1 of the wave of the adhesive stripe can be, for example, in the range of 15 mm to 25 mm.

[0234] Typically, the adhesive strips increase the internal pressure of the machine roll. Too high an internal pressure of the roll may cause telescoping problems. Due to the novel technical solution comprising the adhesive strips with alternating positions, the position of the adhesive can have a controlled variation, thereby reducing the internal pressure of the machine roll. Therefore, telescoping problems can be prevented.

[0235] In order to avoid the problem of telescoping, it may be necessary to move the position of the adhesive strip in a predetermined manner in the transverse direction so that the amplitude of the adhesive strip movement during one wavelength is greater than the width of the adhesive strip. Therefore, advantageously, the width of the adhesive-free area between two adjacent adhesive strips is equal to or greater than the width of the adhesive strip.

[0236] Advantageously, at least 50% of the adhesive coating 120, 121, preferably at least 70% of the adhesive coating 120, 121, more preferably at least 90% of the adhesive coating, and most preferably 100% of the adhesive coating is in the form of alternating adhesive stripes, based on the total area of ​​adhesive on the linerless label (web) 100, 200. Therefore, most advantageously, the adhesive coating 120, 121 consists of alternating adhesive stripes.

[0237] To avoid telescoping problems, each adhesive stripe may need to move in the lateral direction during one wavelength (ie one oscillation period) by an amplitude equal to or greater than the width of the adhesive stripe. Thus, the amplitude A1 of the wave is preferably greater than the width of the adhesive stripe.

[0238] Advantageously, the width of the adhesive-free zone between two adjacent adhesive stripes (determined in the transverse direction) is equal to or greater than the width of each of said adhesive stripes, and the amplitude A1 of the wave is preferably greater than said width of an adhesive stripe.

[0239] In the new solution, the areas with adhesive and without adhesive can vary within a circle around the linerless label roll. In addition, the areas with adhesive and without adhesive can vary at the edge of the roll, that is, the position of the adhesive strips can vary at the edge of the roll. Therefore, the "slit line" can cut through the adhesive strips that change position instead of just between the adhesive strips. Therefore, the new solution can improve the production efficiency of linerless labels (webs) 100, 200. In addition, due to the new solution, some adhesive can be at the edge of the roll without causing too many problems, such as for printing presses. In the customer roll, the varying adhesive area at the edge of the roll also reduces the internal pressure in the roll and provides additional areas for the adhesive to "spread" inside the roll due to the accumulation of internal pressure between the continuous layers of the roll. This helps to avoid or minimize adhesive oozing, that is, adhesive is squeezed out from the edge of the roll, contaminating the side of the roll and causing problems in the final use. Adhesive oozing or oozing can be avoided by choosing a "harder" adhesive, but this usually results in a compromise of reducing other performance parameters of the adhesive. Due to the present invention, the adhesive properties can be selected more freely and the customer roll still has no adhesive oozing / oozing.

[0240] Due to the new technical solution, a smooth machine roll as well as a smooth customer roll can be provided without telescoping problems. The new technical solution may have various technical effects and advantages, such as at least some of the following:

[0241] - Smooth outer surface of linerless label rolls,

[0242] - No telescoping in the machine roll,

[0243] - No telescoping in the client volume,

[0244] - No adhesive bleeding / oozing out, even though there was some adhesive on the edge of the customer's roll,

[0245] - adhesive residues in any parts that come into contact with the web during manufacturing (coating, slitting) or end use (printing press) can be reduced, and

[0246] - This technical solution allows slitting any coil width without specific adjustments.

[0247] If the position of the adhesive strip changes in some other way, the roll may still have a telescoping problem. By setting the adhesive coating 120, 121 to a continuous adhesive strip of alternating position and the adhesive strip having a wavelength (i.e., oscillation period) in the longitudinal direction (i.e., the first direction) of the label web 100 and a position amplitude in the transverse direction (i.e., the second direction) of the label web, the performance of the manufacturing stage and, for example, the performance in a press on demand, and the manual handling of the label after printing may all be significantly improved. Due to the telescoping problem of the linerless label roll, the continuous adhesive strip of alternating position can significantly improve the performance of the manufacturing stage. This can be further improved by using a sinusoidal waveform to the adhesive strip of alternating position.

[0248] The pressure sensitive adhesive coating may be provided on the second side 112 as a continuous adhesive stripe alternating in position in the first direction (i.e., machine direction) of the web, having a minimum area of ​​10%, preferably 25%, more preferably 35%, and more preferably 45% of the total width of the label web. In addition, the pressure sensitive adhesive coating may be provided on the second side 112 as a continuous adhesive stripe alternating in position in the first direction (i.e., machine direction) of the web, having a maximum area of ​​50%, more preferably equal to or less than 48%, and most preferably equal to or less than 45% of the total width of the label web.

[0249] In addition, based on the total surface area of ​​the second side, the total coverage of the pressure-sensitive adhesive coating may be equal to or greater than 10%, more preferably equal to or greater than 30%, more preferably equal to or greater than 40%, and most preferably equal to or greater than 45%. In addition, based on the total surface area of ​​the second side, the total coverage of the pressure-sensitive adhesive coating may be equal to or less than 50%, more preferably equal to or less than 48%, and most preferably equal to or less than 45%.

[0250] refer to Figure 3aFor some end uses, it may be necessary to leave continuous non-adhesive areas / strips 150a near the longitudinal edges of the label web 100. These non-adhesive areas / strips 150, 150a near or on the longitudinal edges may correspond to a minimum of 10%, or 20% or even more than 30% of the total width of the label web 100. The rather wide non-adhesive areas on the outer edges of the labels prevent any seepage of the adhesive in the label roll and help the printing press mechanism to remain clean. Thus, it may simplify the movement of the labels in the printing press and / or help to be able to grip the labels with fingers without contacting the sticky PSA. However, due to the new technical solution including the adhesive strips with alternating positions, continuous non-adhesive areas near the longitudinal edges may not be needed at all.

[0251] The alternating adhesive strips in the linerless labels (webs) 100, 200 provide a good balance between tackiness and manual handling. The non-adhesive areas 150, 150a between the alternating adhesive strips prevent any oozing of adhesive from the label roll and help keep the press mechanism clean. However, the total PSA area is wide enough to provide good enough traction in the press rollers to pull the labels through the press.

[0252] In one embodiment, both the no-bond area 150 and the alternating adhesive strips 120, 121 adjacent to the no-bond area 150 may have a width in the range of 3 mm to 8 mm. In addition, the width of the alternating adhesive strips may be equal to or less than the width of the no-bond area 150. This may provide good properties for the linerless label web and reduce or prevent telescoping problems of the linerless label roll.

[0253] In one embodiment, the linerless label (web) 100, 200 includes a non-adhesive area 150a between two adjacent adhesive strips of alternating positions, and the width of the non-adhesive area is in the range of 1mm to 25mm, more preferably in the range of 2mm to 15mm, and most preferably in the range of 4mm to 8mm. In addition, the width of each of the adhesive strips of alternating positions can be equal to or less than the width of the non-adhesive area 150.

[0254] Thanks to the new technical solution, linerless labels (webs) 100, 200 can be obtained in a cost-effective manner, which can have improved properties for the manufacturing process, so that telescoping of the linerless label roll can be avoided. Furthermore, improved properties can be obtained, for example, for printing presses and for labeling purposes.

[0255] Thus, as discussed, the novel linerless labels (webs) 100, 200 may have several advantages, such as avoiding telescoping issues of machine rolls and customer rolls during the manufacture of linerless labels and increasing the production efficiency of linerless label webs while maintaining good (or even improved) properties for the end user.

[0256] Release coating

[0257] like Figure 1 As shown, the thermally printable face 110 may have a release coating 130 on a first side 111 of the face 110 , ie, the top of the face 110 .

[0258] According to one embodiment, a release coating 130 is applied and cured on the top of the face 110 prior to direct coating and drying of the adhesive coatings 120, 121 on the bottom of the face 110, or prior to transferring the separately dried adhesive coatings 120, 121 to the bottom of the face 110. In other words, preferably, an easily releasable coated face 110 is provided to the process of adding adhesive coatings 120, 121 on the opposite side of the face 110. The benefit of these embodiments is that the release coating 130 can be provided as a completely separate step and possibly in a completely separate facility.

[0259] Thus, a method of manufacturing a linerless label web may include the following steps:

[0260] - Providing a face 110 comprising a release coating.

[0261] According to another embodiment, a release coating 130 is subsequently added on the opposite side of face 110. This embodiment has the benefit that the release coating 130 has not been subjected to any previous processing steps, helping to avoid release agent contamination during these steps. On the other hand, it may be desirable to add the release coating 130 in the same process, because otherwise the adhesive-coated web may not be able to be self-wound into a roll.

[0262] Preferably, the surface 110 is pre-coated with a release coating 130 .

[0263] A separate release coating 130 can be used to improve the self-winding properties of the linerless label. A linerless label web 100 having a pressure sensitive adhesive 120 on one side (bottom side) thereof and a release coating 130 on the other side (top side) thereof can self-wind around itself without the tendency of adjacent layers of the label web 100 to obstruct each other.

[0264] The release coating 130 may be a silicone-based or non-silicone-based release coating. Preferably, the release coating comprises or consists of a silicone-based release coating. The PA silicone-based release coating 130 may include a UV-curable silicone, such as a UV free radical silicone or a cationic UV silicone. The release coating 130 may include one or more layers of the release coating 130.

[0265] Non-heat-curable release coatings are preferred, such as UV-curable silicones, because these layers can be cured without heating the substrate.

[0266] Another function of the release coating 130 may be that it may provide a lower level of friction to the print head and / or other mechanical parts of the printer, thereby minimizing wear of these parts and minimizing the accumulation of adhesive residues. Thus, in one example, a release layer 130 is used to reduce friction to the print head of the printer.

[0267] In one embodiment, the adhesive coatings 120, 121 are coated directly on top of the release coating 130 and dried, or alternatively, a separate dried adhesive coating 120, 121 is transferred on top of the release coating 130. In these embodiments, when the web is wound up into a roll, the pressure sensitive adhesive coating 120 is anchored on the bottom side of the face 110, which is now free of the release coating. When the roll is unwound, the adhesive coating 120 of this linerless web now remains on the bottom of the face 110, while the release coating 130 remains on the top of the face 110.

[0268] Linerless Labels

[0269] The label 200 (also called a linerless label or label product) is a piece of material to be applied to an article. Articles of different shapes and materials can be used with the label 200. The article can be a package. The characteristics and requirements of the label 200 may vary depending on the end use in question, as described in Table 1.

[0270] The label 200 comprises at least a face 110 and an adhesive layer, the adhesive layer comprising or consisting of adhesive strips of alternating positions. The typical way of adhering the label 200 to the article is to use a PSA coating 120. Therefore, the adhesive coating 120 comprises a pressure sensitive adhesive (PSA). The label 200 comprising a pressure sensitive adhesive may be referred to as a pressure sensitive adhesive label. A pressure sensitive adhesive label may also be referred to as a self-adhesive label.

[0271] The label 200 comprising a PSA can be adhered to most surfaces through an adhesive layer without the use of adjuvants such as solvents or the use of heat to strengthen the bond. In that case, the adhesive itself is pressure sensitive. Alternatively, the adhesive can be activatable so as to be pressure sensitive. When pressure is applied to the label at ambient temperature (e.g., between 15°C and 35°C) or even at freezing temperatures below 0°C for cold applications, the PSA forms a bond, adhering the label to the item to be labeled. Examples of pressure-sensitive adhesives include water-based (aqueous) PSAs, solvent-based PSAs, and hot-melt PSAs. As an alternative or in addition, the label can contain other adhesives.

[0272] In the present application, the pressure sensitive adhesive is inherently pressure sensitive and does not require separate activation before it can be dispensed onto the item to be labeled.

[0273] There are different kinds of labels on the market. The label may be a so-called linerless label 200. The linerless label comprises a face 110 and an adhesive on the face 110. Alternatively, the label may be a so-called shrink label, in which a heat-shrinkable polymer face material is sewn and wrapped or sleeved on the item to which the label is attached and shrinks around the item. Shrinkable labels may additionally contain some pressure-sensitive adhesive, or may be produced without a pressure-sensitive adhesive at all or even without a seam adhesive. Furthermore, the label may be an activatable linerless label, in which the adhesive may be activated to be pressure-sensitive, for example using additional heat, moisture or other activation means.

[0274] In the present application, the label is a linerless label. The linerless label can be adhered to the labeled item mainly by a pressure-sensitive adhesive that partially covers the bottom side of the label. The linerless label (web) of the present invention is also tape-type, in other words, it can be self-wound on itself in the form of a roll without an additional release liner.

[0275] Labels can be used in a variety of labeling applications and end-use areas, such as labeling of food, home and personal care products, industrial products, pharmaceutical and healthcare products, beverage and wine bottles, other consumables, etc. Labels are able to provide information about the labeled product, such as product specifications. The information, such as the printing of the label, can include human-readable information, such as images, logos, text, and / or machine-readable information, such as barcodes, QR (Quick Response) codes. A subcategory of labels is the so-called variable information printed (VIP) labels. These labels are at least partially printed before they are assigned to the items to be labeled and carry product-specific information on the individual items to be labeled. For example, VIP labels are used on retail weighing scales for fruits, vegetables, meat and other items sold by weight. Other labels that are printed separately as needed are different types of logistics labels - containing transport or product-specific information, bus or train tickets or other tickets, etc.

[0276] Advantageously, the linerless label (web) 100, 200 comprises a face and alternatingly positioned adhesive strips on a second side of the face. Thus, an improved linerless label may be formed which may have improved properties.

[0277] In one advantageous example, the linerless label (web) consists of the following layers:

[0278] -noodle,

[0279] - a release coating on a first side of the surface, and

[0280] - One or more alternating adhesive stripes on the second side of the face.

[0281] Linerless Label Web

[0282] Figure 1 By way of example, a cross section Sx, Sy of a linerless label (web) 100 , 200 is shown, which may be a linerless label web 100 or a single label 200 .

[0283] The linerless label web 100 refers to a structure including a so-called continuous face 110 and an adhesive 120 disposed on one side of the face 110. The linerless label web 100 is usually processed by moving on a roll. Between processing stages, the label web 100 can be stored and transported as a roll. From the linerless label web 100, individual labels 200 can be cut. In the manufacturing process of customer rolls, the linerless label web 100 is wound into a machine roll, and the machine roll is unwound and slit into smaller customer rolls.

[0284] Machine rolls and customer rolls

[0285] The linerless label roll can be a so-called machine roll 570 or a customer roll 300. In the manufacturing process of linerless labels, linerless labels are usually rolled into machine rolls. The width of the machine roll (i.e., the linerless label web before being cut into customer rolls) is usually several times the width of the final customer roll 300. The width of the machine can be, for example, 1 to 3 meters.

[0286] A single machine roll can be arranged with alternating positions of continuous adhesive strips at different transverse positions (adhesive strip positions) and thus be used to produce different types of customer rolls. In some cases, a slitting process can be used to provide different adhesive strip positions.

[0287] Typical machine reel diameters DMR are 500 mm to 1500 mm, most typically 500 mm to 1000 mm. Thus, the top layer of a complete machine reel may have a length of, for example, 1 m to 5 m.

[0288] The diameter DCR of the customer roll 300 may be, for example, between 50 mm and 150 mm. Thus, the customer roll 300 may be smaller than about one tenth of the machine roll. Thus, the top layer of a complete customer roll may have a length of, for example, 0.1 m to 0.5 m.

[0289] The linerless label web 100 may be referred to as a (linerless label) customer product roll, customer roll, or product roll after being rolled into a customer roll 300. Depending on the diameter of the label roll and the thickness of the linerless label material, a single roll may contain, for example, 10-100 meters of label material (i.e., linerless label web 100).

[0290] A typical linerless label web 100 customer roll 300 consisting of a single label width may have a width of approximately 10 to 100 mm. Very common widths can be found in the middle of the above range, i.e. between 40-60 mm.

[0291] The face 110 may be provided with a plurality of alternating adhesive strips. Later, the wider web width of the machine roll produced in the manufacturing process may be slit to the correct width of the customer roll 300. The customer roll 300 may have one or more alternating adhesive strips, for example, several alternating adhesive strips.

[0292] The total PSA coverage of the label web 100 of the customer roll 300 in the transverse or second direction may be less than 50%, preferably equal to or less than 48%, and most preferably equal to or less than 45%. The PSA may be provided in one or more alternating continuous adhesive strips, leaving one or more no-bond areas 150 between the strips. Thus, the width of the no-bond area between two alternating adhesive strips is advantageously equal to or greater than the width of each adhesive strip adjacent to the no-bond area.

[0293] Furthermore, according to one embodiment and with reference to Figure 2a and 3a The linerless labels (webs) may include one or more areas along the longitudinal (machine direction) edges that are free of adhesive to further prevent adhesive from seeping out the sides of the label roll and / or to facilitate manual grabbing of the labels from the edges without contacting the sticky adhesive. The non-adhesive areas 150, 150a of the linerless labels (webs) 100, 200 may also help minimize adhesive residue accumulation inside the printer or cutter mechanism.

[0294] The linerless label (web) 100, 200 may include one or more characteristics selected from the group consisting of:

[0295] - The coating weight of the adhesive layer 120 can be 15-20 g / m 2range (dry coating weight) to ensure both: good anchorage and good adhesion to different types of surfaces.

[0296] - The adhesive layers 120, 121 are preferably water-based adhesive layers. In addition, acrylic-based adhesives are more environmentally friendly and also provide a more suitable final tack build-up over time, helping to reduce contamination of the printing press.

[0297] - The adhesive layers 120, 121 are arranged in alternating adhesive strips in the longitudinal direction. This ensures suitable label properties for each given end use and also helps to reduce contamination of the printing press. Furthermore, this can prevent telescoping problems of machine roll and customer roll. The alternating adhesive strips can have the shape of a sine wave.

[0298] - Optionally, there is no special primer between the thermal paper and the PSA to enhance the adhesive anchoring of the adhesive on the thermal paper. Sufficiently high anchoring can be achieved by using a sufficiently high adhesive coating weight and allowing the adhesive to dry completely. This simplifies the manufacturing process, saves an additional processing stage and helps to reduce costs.

[0299] Water-based acrylic adhesives have a lower initial tack, which means that after being unwound from the label roll, the PSA is less immediately tacky when guided through the printing press than, for example, hot melt PSAs. This, together with other features of the label, helps to minimize the build-up of adhesive residues inside the printing press. The final tack is only developed after the label has been dispensed and remains on the labeled item for a long time. The label may even be removable for a period of time (minutes) before a more permanent tack type is established. The specific properties of the PSA naturally depend on the exact formulation of the adhesive and the surface material to be labeled.

[0300] In order to provide cost-effective, efficient and trouble-free operation in a user-friendly and sustainable manner, several requirements are placed on linerless label products.

[0301] The adhesive-free area can reduce manufacturing costs, is good for the environment, and prevents the adhesive coating 120 from accumulating on the blades and rollers of the linerless label printer. However, during the manufacturing process of the linerless labels, the adhesive strips may cause telescoping problems. The linerless labels (webs) according to the present specification can reduce the manufacturing problems caused by the adhesive strips on the surface of the face. Due to this new technical solution, telescoping of the linerless labels (webs) can be prevented while still providing the advantages obtained by using the adhesive strips.

[0302] Preparation method

[0303] For example, the alternating position adhesive stripes may be produced by using at least some of the method steps and / or elements described in this specification.

[0304] Figures 4a to 8 and Figures 10 to 11 Some exemplary steps and elements for manufacturing a linerless label (web) are shown.

[0305] The adhesive strips 120, 121 of alternating positions can be applied and dried directly on the face 110. Alternatively, the adhesive strips 120, 121 of alternating positions can be applied and dried on a separate carrier first and then transferred to the face 110. The former method has the advantage of having fewer manufacturing steps, but on the other hand, requires those settings not to overheat the face material in the case of heat-sensitive face materials. The latter has the benefit of being able to perform the drying phase more freely, but on the other hand requires additional processing steps to transfer the dried adhesive to the face 110.

[0306] During the manufacturing process of the linerless labels (webs) 100, 200, the adhesive coating 121 comprising or consisting of the alternating adhesive stripes is dried into the pressure sensitive adhesive coating 120. Advantageously, the alternating adhesive stripes comprise a water-based acrylic adhesive.

[0307] The manufacturing process of the linerless label (web) 100, 200 may include an actuator that can oscillate to form adhesive strips with alternating positions. While forming the adhesive strips with alternating positions, the actuator can be moved at least in the cross direction CD of the web. By continuously moving the actuator in an oscillating manner, the position of the adhesive strips in the machine roll can be controlled, and therefore, the machine roll can have a smooth roll profile.

[0308] The actuator may oscillate while the linerless label web is running, whereby the actuator may cause a predetermined pattern of adhesive stripes of alternating positions.The actuator preferably performs at least a lateral movement.

[0309] The oscillation frequency of the oscillating actuator and the speed of the substrate may be optimized to obtain a predetermined position amplitude and position frequency of the adhesive stripe.

[0310] One complete oscillation of the actuator may form one oscillation cycle of the adhesive stripe with alternating positions.The actuator may have a specific oscillation frequency and amplitude to prevent telescoping of the machine roll as well as telescoping of the customer roll.

[0311] Frequency refers to the number of oscillations in one unit of time. In the present application, frequency refers to the number of oscillations in one second. Thus, frequency refers to the number of oscillations produced by the actuator per second during the manufacturing step of the adhesive strip.

[0312] The frequency of the actuator during the manufacturing step of the adhesive strip of position alternation can be in the scope of for example 0.1-10Hz, for example 0.5-1.5Hz.Frequency is selected based on the speed of web material, but there is an available upper limit, because fluid adhesive can not be reliably coated in the mode of position alternation under any frequency and can not reproduce.For the given fluid characteristic (for example viscosity) of adhesive to be coated, the preferred frequency that actuator moves is about 1Hz, for example 0.5-1.5Hz.If move faster, adhesive may experience for example ploughing effect (ploughing effect), wherein the edge of adhesive strip begins to accumulate the thickness increased, because the speed that actuator pushes adhesive sideways exceeds the speed allowed by the viscosity of adhesive.These are either reflected in the quality of adhesive coating (the thickness of adhesive strip is uneven), or also may cause web material braking.

[0313] If the actuator moves too fast, the manufacturing process can be very challenging due to the aforementioned fluid properties of the adhesive, especially in the case of water-based acrylic adhesives. However, fast-moving mechanical items in close proximity or contact with the fast-moving web can also cause other mechanical issues, such as vibration, which can also cause web braking.

[0314] In an advantageous example, the web moves 0.5 to 10 meters in one oscillation cycle, preferably 2 to 7 meters in one oscillation cycle, and most preferably 3 to 5 meters. Therefore, advantageously, the position-alternating adhesive strips have a wavelength in the range of 0.5m to 10m, preferably in the range of 2m to 7m, and most preferably in the range of 3m to 5m. The position wavelength WL refers to one oscillation cycle of the position-alternating adhesive strips.

[0315] In one embodiment, the movement of the substrate during one oscillation cycle of the actuator is in the range of 3m to 5m. Thus, in one embodiment, the position-alternating adhesive stripes have a wavelength in the range of 3m to 5m.

[0316] The characteristic time required for the actuator to complete one oscillation cycle can be called the oscillation period P1. When the substrate (surface or carrier material) moves, in a time equal to one oscillation cycle of the actuator, the substrate has moved along a distance equal to the wavelength WL. Therefore, the wavelength obtained can depend on both the speed of the substrate and the frequency of the actuator.

[0317] The actuator can be:

[0318] - a pneumatic actuator, ie an actuator using compressed air. A pneumatic actuator can be moved forwards and backwards at least in a transverse direction. A pneumatic actuator can be particularly suitable for forming an adhesive strip having a sinusoidal wave shape.

[0319] - Hydraulic actuators. Hydraulic actuators can move forward and backward at least in the transverse direction. The speed and direction of the movement can be controlled. Hydraulic actuators can be used to form different kinds of shapes.

[0320] -Electronic actuators. Electronic actuators can move forward and backward at least in the transverse direction. The speed and direction of the movement can be controlled. Electronic actuators can be used to form different kinds of shapes.

[0321] Thus, all actuators can move at least forward and backward. In addition, for example, hydraulic and electronic actuators can move in any direction. In an advantageous example, the speed and movement of the actuator can be controlled. In one embodiment, the actuator can move in any direction.

[0322] The actuator can be based, for example, on a screw that rotates with a motor, on which a nut travels and in concert to move the coating device in the transverse direction of the web. In its simplest form, the motor's rotation speed is adjusted to affect the position frequency, and the screw is equipped with a limiter that changes the direction of rotation and moves the nut back and forth a given distance. Adjusting this distance changes the position amplitude.

[0323] Instead of a basic mechanical actuator, any hydraulic or electronic linear drive or other system can be used to generate the lateral movement required to move the coating device relative to the running web. In principle, even special gravure rollers can be used for the coating process, but this coating method is not easy to adjust to achieve a predetermined position-alternating coating as required.

[0324] The waveforms produced by the predetermined selection of the position frequency and position amplitude of the bars can range from smoothly varying sinusoidal waveforms to more sharply varying almost step-changing waveforms. However, all can be characterized by having a specific position dominant frequency and dominant amplitude behavior.

[0325] Actuators can be “mechanically controlled,” such as adjusting the speed and travel of a screw as mentioned above, or varying the flow of pneumatic or hydraulic fluid and the position of a limit valve in a pneumatic or hydraulic cylinder. On the other hand, any waveform can be achieved by a “computer or electronically controlled” system, which might vary the speed of a motor, the flow of hydraulic fluid, or the drive settings of an electric linear actuator.

[0326] For cost reasons, the actuator is preferably a pneumatic actuator that can move fast enough and can be "mechanically controlled" and adjusted. Most preferably, the actuator is a pneumatic actuator that can move forward and backward so that the amplitude and frequency of the actuator can be controlled.

[0327] The machine speed of the adhesive coating process can be, for example, 100-600 m / min. Thus, when the oscillating actuator forms the alternating adhesive stripes by applying adhesive to form the alternating adhesive stripes or by removing adhesive to form the alternating adhesive stripes, the speed of the substrate (e.g., surface) can be in the range of 100 m / min to 600 m / min.

[0328] The oscillating actuator can apply the adhesive coating. In this embodiment, the oscillating actuator can include a nozzle. In addition, the oscillating actuator can include a blocking gasket 870 (such as Figure 8 ), forming adhesive strips with alternating positions and non-adhesive areas between the adhesive strips.

[0329] Alternatively, the oscillating actuator can remove at least some adhesive coatings.Therefore, the oscillating actuator can comprise a blade, and this blade removes at least a portion of adhesive coatings to form an adhesive strip of position alternation on the surface of the face.According to the predetermined position and the optimization result of the adhesive strip, the blade can move with different frequencies in the horizontal direction.In the present embodiment, removing the adhesive coating can for example be realized by wiping the blade, and wherein the blade can be arranged to be 75-85 degree with respect to the wiping angle of the substrate surface.

[0330] As discussed, adhesive coatings 120, 121 include alternating adhesive stripes and adhesive-free areas between the adhesive stripes. Advantageously, adhesive covers 10% to 50% of the total area of ​​face 110, and more advantageously, adhesive covers 30% to 50% of the total area of ​​the second side of the linerless label.

[0331] The adhesive may be provided as "oscillating" strips along the longitudinal direction (ie, first direction) of the label web 100. Thus, in the transverse direction (ie, second direction) of the label web 100, the face 110 may include alternating areas with and without adhesive.

[0332] Providing adhesive-free strips / areas 150, 150a along the label web 100 can facilitate manual handling and / or dispensing of the labels. Figure 2a and 3a As shown, providing adhesive-free strips / areas along the longitudinal edges of the label web 100 may be advantageous from a printer's perspective. Thus, at least contamination of the printer's components with adhesive may be reduced. Finally, from an economic and environmental perspective, it may be advantageous to provide the label 200 / label web 100 with adhesive only on the portion of the label that is necessary to provide the desired adhesion.

[0333] according to Figure 4aThe embodiment shown provides a method for manufacturing a linerless label web 100 including an alternating adhesive strip. The method includes setting a face (step 401), applying an alternating adhesive strip 121 to the face (steps 402, 403), optionally ensuring that the non-adhesive area 150 has a predetermined level of moisture (step 404), and heat drying the alternating adhesive strip to form a pressure-sensitive adhesive 120 (step 405). Steps 402-404 of the method can be performed simultaneously or stepwise. The alternating adhesive strip can be provided in the following manner: directly applying adhesive in the form of an alternating adhesive strip, or applying a continuous adhesive layer and then removing part of the adhesive to form an adhesive strip.

[0334] Figure 5 1 shows an apparatus according to an embodiment. The apparatus comprises a coating unit 580 for applying an adhesive coating 121 onto a face 110. Downstream of the coating unit 580, the apparatus may comprise a unit 400 for removing adhesive. The unit 400 for removing adhesive may be an oscillating actuator. Downstream of the unit 400, the apparatus comprises at least one drying unit 400 for drying the position-alternating adhesive strips 121. The drying unit comprises at least one drying device 561. After the drying unit, the linerless label web 100 thus formed is arranged to be rolled onto a linerless label web roll 570.

[0335] In one embodiment, the alternating adhesive stripes are provided by first applying an adhesive coating 121 to 100% of the area of ​​the face 110 using a coating unit 580. Afterwards, an oscillating actuator can remove some of the adhesive coating 121 from the face 110, thereby providing the face 110 with adhesive areas and non-adhesive areas 150 alternating in the transverse direction of the face 110, thereby forming alternating adhesive stripes. The adhesive removal is performed before drying the adhesive in at least one drying unit 560. The adhesive removal can be performed by the unit 400, which in this embodiment can be an oscillating actuator.

[0336] Therefore, the method may include the following steps:

[0337] - providing one or more adhesive stripes of alternating position by removing at least some of the adhesive coating with an oscillating actuator before the adhesive coating dries to form a pressure sensitive adhesive coating.

[0338] Specifically, the method may include the following steps:

[0339] - applying an adhesive coating to a substrate, which may be a surface or a carrier material,

[0340] - removing at least 50% of the adhesive coating from an area of ​​the substrate by using an oscillating actuator to provide a non-adhesive area and one or more alternating adhesive stripes.

[0341] In this embodiment, the oscillating actuator may include a wiping blade, wherein the blade is preferably disposed at a wiping angle of 75-85 degrees relative to the surface of the substrate.

[0342] Applying adhesive coating 121 to 100% of the area of ​​face 110 provides the effect that the areas from which adhesive is subsequently removed will also be wetted by the water contained in the adhesive. This may be particularly advantageous because, due to the alternating adhesive strips, it may be difficult to apply moisture only to the areas between the adhesive strips. When adhesive coating 121 is applied to the entire area of ​​face 110, water is absorbed into face 110 and after forming the alternating continuous adhesive strips, a small amount of adhesive remains on face 110, also on the areas from which adhesive has been removed.

[0343] The residual amount of adhesive on the non-adhesive area may be about 0-5.0 g / m 2 , for example 0.5g / m 2 Up to 2g / m 2 , or 2.0g / m 2 Up to 5.0g / m 2 In one embodiment, the non-bonded area may contain 0 to 0.5 g / m 2 In another embodiment, the non-adhesive area may contain 0.5 g / m 2 Up to 5g / m 2 In a preferred embodiment, the non-adhesive area may include a residual amount of adhesive coating within a range of 0 g / m 2 Up to 1g / m 2 In the range of 0.1g / m 2 Up to 1g / m 2 The residual amount of adhesive coating within the range. However, the residual amount of adhesive is so small that it cannot provide significant adhesive properties after drying, so it is called no adhesion.

[0344] Thus, advantageously, the non-adhesive areas may contain some moisture because some of the adhesive has been removed and the areas from which the adhesive was removed are wetted by water from the adhesive coating.

[0345] Thus, in one embodiment, the adhesive coating is applied to a substrate as a carrier material and then thermally dried to form a pressure-sensitive adhesive coating on the carrier material, after which the pressure-sensitive adhesive is transferred from the carrier material to the face.

[0346] Thus, the adhesive coating may be applied to the second side of the face, or the pressure-sensitive adhesive coating may be transferred from a carrier material to the second side of the face.

[0347] In one embodiment, the adhesive coating is first applied to the face and then thermally dried to form a pressure sensitive adhesive coating on the face. The adhesive coating 121 may be applied to the face 110 using a contact coating method such as roller coating.

[0348] In one embodiment, the adhesive coating 121 is applied by direct gravure coating. In direct gravure coating, the adhesive is transferred directly to the substrate, such as face 110, from a gravure roll.

[0349] Part of the adhesive can be removed from the face by using an oscillating actuator, which includes, for example, a blade, such as a nylon blade. The blade can be called a scraper. The blade can refer to any device suitable for removing adhesive from the web. The blade has the following effect: when removing the adhesive, the blade simultaneously provides pressure to the face 110, thereby pushing moisture, i.e., water contained in the adhesive, into the face 110. In addition, the oscillating motion of the actuator provides an adhesive strip with alternating positions, and each oscillation cycle of the adhesive strip with alternating positions has an amplitude and a wavelength.

[0350] The dry weight content of the adhesive coating 121 removed from the web (i.e., the face 110) may be different from the dry weight content of the adhesive coating 121 applied to the face 110. The dry weight content of the adhesive coating 121 removed from the web may be, for example, 0.1% to 5.0% lower than the dry weight content of the adhesive coating 121 applied to the web. In one example, the dry weight content of the adhesive coating 121 removed from the web is 0.5% to 1.0% lower than the dry weight content of the adhesive coating 121 applied to the web. The residual amount of the adhesive coating 121 on the non-bonded area 150 and the moisture transferred from the adhesive coating 121 to the face 110 have the effect of preventing the substrate temperature from rising, which is particularly advantageous when the face includes a direct thermal coating.

[0351] In embodiments where the face is thermally printable, it can be ensured that a certain target level of moisture is present on all portions / areas of the linerless label web 100 before the web enters the drying stage. During the drying stage, evaporation of moisture maintains the web temperature below the activation temperature of the thermal coating in areas without adhesive / bonds as well as in areas with water-based adhesive / bonds.

[0352] Figure 6A detailed view of the method and apparatus according to an embodiment is provided. The adhesive coating 121 is applied to 100% of the area of ​​the face 110 by the coating unit 580. Thereafter, some of the adhesive coating 121 is removed from the face 110 by using the oscillating actuator 400, 690 so that the face 110 has alternating adhesive strips and non-adhesive areas 150. Figure 6 The unit 690 in the embodiment may be an oscillating actuator 400, which may be configured to remove the adhesive coating 121, Figure 6 The dashed line magnification is visualized as a black block 121. The dashed line magnification shows the face having the adhesive coating thereon in the Sx, Sz plane. Figure 6 The gray droplets of 400 show the adhesive coating removed from the face 110 by the oscillating actuator 400. The adhesive removed from the face 110 may be collected and returned to the coating unit, as shown by the curved arrows between the units 400, 690 and the coating unit 580.

[0353] According to one embodiment, the oscillating actuator includes a blade arranged at an angle of almost 90° relative to the web (i.e., the face 110). For example, the blade can be arranged at a wiping angle of 75° to 85°, such as 80°, relative to the web. The blade can be arranged in a forward direction relative to the web. The web tension can be, for example, 100-250 N / m. The web tension can be, for example, 150 N / m. Higher web tension and / or higher wiping blade angles can provide pressure to the face 110, thereby pushing more water contained in the adhesive coating 121 into the face 110 while removing the adhesive. The web tension and blade angle also have an effect on the amount of adhesive removed from the face 110. Higher web tension and / or blade angles may be the cause of a greater amount of adhesive removed from the face 110. Moisture may be particularly useful if the linerless label (web) 100, 200 is thermally printable.

[0354] The distance between applying the adhesive coating 121 and removing the adhesive coating 121 can be, for example, 20 cm to 1 m. The residence time between applying the adhesive coating 121 and removing the adhesive coating 121 can be, for example, 0.05 to 3 seconds. In an advantageous example, the machine speed of the process is in the range of 150 m / min to 250 m / min, and the distance between applying the adhesive coating 121 and removing the adhesive coating 121 is in the range of 30 cm to 90 cm. Therefore, the residence time between applying the adhesive coating 121 and removing the adhesive coating 121 is preferably between 0.1 seconds and 0.5 seconds. The longer the distance between applying the adhesive coating 121 and removing the adhesive coating 121, that is, the distance and / or residence time between the coating unit 580 and the oscillation actuator 400, 690, the longer the time that the adhesive contacts the surface 110, and therefore the higher the moisture content transferred from the adhesive coating 121 to the surface 110.

[0355] In one embodiment, if Figure 7-8 As shown, it is possible to provide an adhesive strip with alternating positions, and the adhesive coating 121 is only partially applied to the surface 110, thereby providing the surface 110 with alternating adhesive areas 121 and non-adhesive areas 150 in the transverse direction of the surface 110. The figures only illustrate the principle of the method, and the shape of the adhesive strip is not shown in these figures. In this embodiment, the coating unit 580 is an oscillating actuator 400. Therefore, the surface 110 will obtain an adhesive strip 121 with alternating positions. The adhesive area is Figure 7 Shown as black blocks.

[0356] refer to Figure 7-8 , the alternating adhesive strips 121 can be applied directly to the substrate. The substrate can be the first side of the face or the second side of the face. Alternatively, the substrate can be a carrier material, and the pressure sensitive adhesive coating can be transferred from the carrier material to the first side or the second side of the face. After the linerless label web is wound into a roll, the PSA coating will be anchored on the second side (i.e., the bottom side) of the face material, regardless of whether the adhesive coating is applied or transferred to the first side or the second side of the face.

[0357] like Figure 7 As shown in the enlarged view of the dotted line in FIG. 1 , the adhesive coating 121 can be applied to the face 110 in continuous parallel strips extending in the machine direction of the label web 100. In addition, due to the oscillating actuator, the parallel strips can have a position alternating form, such as Figure 2a and 3a shown.

[0358] In one embodiment, the adhesive may be applied by using a contact coating method, such as roller coating, wherein the adhesive is applied to a transfer roller using a nozzle. The nozzle may be provided with a barrier pad (in Figure 7 10 is a block filled with oblique lines in the figure), so that the adhesive coating 121 is only delivered to certain lateral positions on the transfer roller. Therefore, the adhesive coating 121 on the face 110 is also alternated in position. The width of the adhesive can be changed as needed by adjusting or changing the blocking pad in the nozzle. In this embodiment, the oscillating actuator includes the nozzle that forms the adhesive strip of alternating position.

[0359] In one embodiment, if Figure 8As shown, the transfer roller 580a of the coating unit 580 can be coated with adhesive 120 using a coating nozzle 580b. The adhesive 120 from the surface of the transfer roller 580a is picked up on the carrier web 611 to form the carrier 611 coated with adhesive. The nozzle can oscillate to form an adhesive strip with alternating positions. The coating nozzle 580b can be arranged with a blocking pad 870 so that the adhesive is only delivered to certain lateral positions of the transfer roller 580a. Therefore, the adhesive coating 121 on the carrier 611 also alternates in position. Due to the oscillating motion of the nozzle, the adhesive coating is in the form of an adhesive strip with alternating positions. By adjusting or changing the blocking pad 870 in the nozzle 580b and / or by adjusting the oscillation frequency of the nozzle, the position of the adhesive can be changed as required.

[0360] Drying Steps Example

[0361] The alternating adhesive stripes 121 can be dried on the face 110 or on the carrier 611. The result of drying is a pressure-sensitive adhesive 120. Preferably, the alternating adhesive stripes are dried on the face 110. This can increase the ease of the manufacturing process and, at least in some cases, further increase the productivity of the manufacturing process.

[0362] Drying includes heating. The choice of heating method will affect the balance between radiant heat transfer and convective heat transfer. The adhesive 121 can be dried into a PSA by using at least one of the following: infrared energy, microwave energy or air blowing. Preferably, the adhesive 121 is dried by air drying or by air drying together with another type of drying. This ensures an appropriate preheating level of the adhesive to begin evaporating moisture from the adhesive, but prevents crusting on the top surface of the adhesive, which would prevent moisture from escaping deeper into the adhesive layer. The drying stage of the machine including the drying unit may have a total length of 20 to 30 meters. The adhesive coating 121 may be dried in at least one drying unit 560.

[0363] After the adhesive has dried, the linerless label web 100 having the pressure sensitive adhesive side 110 thereon is wound onto a machine roll 570 .

[0364] The adhesive applied to the face 110 comprising paper may penetrate into the face 110 and soften the face 110 or weaken the hydrogen bonds therein. As a result, the paper face 110 may lose its quality, which in turn prevents further steps of label processing, such as printing or die-cutting. In the case of a plastic face 110, drying a water-based adhesive applied to the face 110 is not possible or has caused problems. For example, polypropylene or polyethylene are not suitable materials for a label face 110 with a water-based adhesive because high temperatures are required for the drying part, which may cause these film materials to melt or deform. The challenges faced by thinner plastic film thicknesses are more severe, but thinner plastic film thicknesses are a trend to save materials and improve sustainability by reducing the use of plastic materials.

[0365] According to one embodiment, the adhesive for the linerless label web is dried separately on the carrier material 611 before the adhesive is adhered to the face of the label. This avoids problems caused by heat sensitivity and enables the use of environmentally friendly water-based adhesives in such linerless labels. This approach allows a wider range of substrate materials to be selected for the label, including substrate or coating materials, even if they have lower physical or chemical properties, but are still fully suitable for on-demand linerless printing and short-term label applications.

[0366] Figure 4b A method according to an embodiment is illustrated. The method allows for applying a PSA on a sensitive linerless face and forming a linerless label web 100 without exposing the face 110 to high temperatures. Steps 402-407 may also be referred to as stages or phases.

[0367] It should also be understood that the adhesive coating method and drying method explained earlier in this specification are also applicable to the following embodiments.

[0368] A water-based adhesive is preferably used in the following embodiments. For the reasons discussed in this specification, the adhesive is preferably a water-based acrylic adhesive.

[0369] In the following, reference is made to Fig.10 and 11 Two alternative methods of manufacturing are described in more detail. The main difference between the two methods is how the carrier material 611 for the dry adhesive coating is arranged. Fig.10 In the embodiment schematically described in , the carrier material is arranged as an endless belt. Fig.11 In another embodiment schematically depicted in FIG. 1 , the carrier material is provided as a reusable batch of tape material.

[0370] In a first step 402b, an adhesive coating 121 is applied to a carrier material 611 by using an oscillating actuator, such as an oscillating nozzle. Then, in a second step 405, the adhesive coating 121 is dried / cured into a PSA 120 on the carrier material 611 by conveying the carrier through a dryer. In a third step 406, the dried water-based adhesive 120 is transferred to the face 110 of the label web 100. Finally, in a fourth step 407, the face with the pressure-sensitive adhesive is wound into a roll of linerless label web 100. In this embodiment, the drying / curing of the adhesive coating 121 occurs on a separate carrier material 611, so that this face is not exposed to temperatures exceeding the activation temperature of the heat-sensitive coating.

[0371] The carrier material 611 can be a tape 611a, such as a silicone tape, a plastic tape, such as a nylon tape, or a metal tape, such as a steel tape. Alternatively, the carrier material 611 can be a batch of roll tape materials 611a, wherein the carrier materials 611, 611b can be film roll tape materials, preferably polyethylene terephthalate (PET) roll tape materials or other film materials that withstand drying temperatures. The tape can include a closed surface. According to PPS 10 of ISO 8791, the outer surface of the tape can include a roughness of 0.2-3.0 μm, preferably 0.4-1.0 μm.

[0372] The alternating adhesive strips may be in contact with the tape for at least 1 second, or 1.5 seconds, preferably at least 1.8 seconds, or at least 2.0 seconds, preferably not longer than 10-20 seconds, and most preferably not longer than 8 seconds, to ensure an efficient manufacturing process. The thickness of the metal tape may be, for example, 0.2-4.0 mm, preferably 1-2 mm. The density of the metal tape at a temperature of 20° C. may be 7500-8500 kg / m 2 , preferably 7700-8050kg / m 2 , thereby ensuring a sufficiently high heat capacity for effective heat transfer and heating. The roughness of the belt coating according to PPS10 of ISO 8791 can be 0.2-3.0 pm, preferably 0.4-1.0 pm. The thermal conductivity of the metal belt at a temperature of 20 degrees Celsius can be, for example, 13-21 W / mK, or 14-15 W / mK. The thermal conductivity of the metal belt at a temperature of 100 degrees Celsius can be, for example, 14-22 W / mK, or 15-16 W / mK.

[0373] For the purpose of this specification, hereinafter, the terms "carrier" and "carrier material" may refer to an endless tape or a batch of tape materials. The carrier 611 may include at least one release coating.

[0374] The adhesive coating 121 may be dried on one or both sides of the carrier, ie above and / or below the carrier. The adhesive coating 121 may be dried directly and / or indirectly. Drying may be performed indirectly by heating the carrier.

[0375] Fig.10 An apparatus according to one embodiment is shown. The apparatus comprises a carrier material 611 in the form of a strip 611a. Adhesive 121 is applied to the strip 611a by a coating unit 580, which may be an oscillating actuator 400, preferably comprising a nozzle. The coating unit 580 is arranged to apply adhesive 121 to the strip. Drying may be performed by one or more drying devices 560, 561.

[0376] Fig.10 The equipment in the embodiment includes an unwinder 612 for the face 110. The face 110 may be in the form of a web wound into a roll. After drying, the adhesive 120 may be adhered to the face 110. The unrolled face 110 on the belt 611 and the dried water-based adhesive may be attached in the roller gap 660 to form the linerless label web 100. The formed linerless label web 100 is wound into a roll 570. The label web roll 570 may be stored and / or transported for later processing. The label web roll 570 may be further processed at other locations. Fig.10 The apparatus may further include a cooling cylinder 650 .

[0377] The length, speed and / or temperature of the belt may affect the drying process of the water-based adhesive on the belt. The length of the belt may be at least 10 m and not more than 50 m. The speed of the belt may be 200-1200 m / min. The drying temperature of the water-based adhesive on the belt may be 80-85 degrees Celsius or even higher. Preferably, the drying temperature is at least 75 degrees Celsius to ensure that the water-based adhesive becomes completely dry and provides maximum adhesive properties, such as adhesion.

[0378] Fig.11 An alternative manufacturing method is schematically shown, where, as an alternative to an endless belt, the carrier 611 is provided as a reusable batch of web material 611b. This allows for production of batches of predetermined lengths and multiple reuse of the carrier material. Benefits of this method include, but are not limited to, the ability to use existing backing materials, such as siliconeized PET backing materials, as a carrier.

[0379] exist Fig.11, the carrier 611, 611b is unwound at the carrier unwinder 710 and directed to the adhesive coating station 580. The carrier is preferably a pre-siliconized carrier. The carrier 611b is forwarded through a dryer or a series of dryers 560, 561. The face 110 is unwound at the face unwinder 612 so as to meet the carrier 611 in the roller gap arrangement 660, in which the PSA120 from the carrier 611 is transferred to the face 110. After this transfer, the face 110 is rewound onto the machine roll together with the PSA120 using a linerless winder 770. The used carrier material 611, 611b from which the PSA 120 has been removed is directed to the carrier rewinder 780. The material is reusable and can be conveyed back to the unwinder 710 for reuse. Fig.11 The apparatus may further include a cooling cylinder 650. The cooling cylinder may be located before the location where the dry water-based adhesive (PSA) is adhered to the surface 110.

[0380] It should be understood that the earlier Fig.10 All heating / drying methods explained in the endless belt embodiment of the present invention also apply here, provided that they are applicable to the reusable batch carrier selected for use. It should also be understood that all adhesive coating methods previously explained in this specification also apply here. Preferred coating methods are explained in more detail in this specification.

[0381] Thus, as disclosed in the present application, the adhesive coating 121 is arranged in the shape of alternating adhesive stripes. This means that the adhesive coating can be applied to the carrier material 611, 611a, 611b in continuous, alternating, parallel strips, which extend in the machine direction, i.e. in the longitudinal direction of the carrier. The alternating adhesive stripes can be obtained, for example, by using any of the above-mentioned methods.

[0382] about Figure 5-8 , again refer to Figure 4a , steps 401-405 may occur in various orders. Figures 10 to 11 , again refer to Figure 4b , steps 402 to 407 may occur in various orders.

[0383] Thanks to the invention, a number of advantages can be obtained. In particular, telescoping problems of machine rolls can be prevented. Furthermore, telescoping problems of customer rolls can be prevented. Still further, the ease and controllability of the manufacturing process of linerless labels can be improved.

[0384] In addition to the above advantages, at least some of the following advantages can be further obtained:

[0385] 1) Reliable adhesion / tack can be achieved for all those different types of surfaces to which labels will be manually dispensed or applied, for example, during preparation of an order (e.g., in a kitchen) or when labeling various items for an order (e.g., cups, boxes, wraps, bags, or other packaging).

[0386] 2) Easy repositionability can be achieved, so that the label is first applied to a first surface and then repositioned to another surface. For example, the label may first be used as a note in the kitchen and then affixed to a finished dish.

[0387] 3) Easy removability can be achieved, for example for customers to remove labels used as package closures or seals.

[0388] 4) Permanent final tack of the label can be achieved in applications where a lower initial tack is advantageous to reduce adhesive build-up in the printing press, but a permanent type of tack of the label is preferred after dispensing onto the item to be labeled.

[0389] 5) Chemistry suitable for direct or indirect food contact can be obtained.

[0390] 6) Sustainability can be obtained to support the shorter life of such labels, i.e. their chemistry will not impose an undue burden on the environment or require any special waste management procedures compared to other wastes generated in the processes and activities in which such labels are used.

[0391] 7) Water-based acrylic PSAs can offer additional benefits, such as better sustainability, involving fewer fossil-based raw materials and fewer volatiles during manufacturing and end-use.

[0392] Experimental testing

[0393] Example 1

[0394] A reference machine roll comprising adhesive strips but continuous adhesive strips without position alternation was produced, as well as a novel roll comprising adhesive strips with position alternation.

[0395] The reference roll includes adhesive strips with adhesive-free areas between the adhesive strips. The width of the adhesive strips is substantially the same as the width of the adhesive-free areas.

[0396] The novel roll comprises an adhesive strip of alternating position, comprising an adhesive-free area of ​​the same width as the reference roll and an adhesive strip of the same width. The amplitude of the adhesive strip of alternating position is 25 mm. The frequency of the actuator during the manufacturing step of the adhesive strip of alternating position is 1 Hz. The driving speed of the web is approximately 200 meters / 60 seconds, so it moves several meters per second.

[0397] The machine rolls were slit by using a slitter. The width and length of each customer roll varied during the test.

[0398] The reference machine rolls had noticeable telescoping issues of several centimeters or more, affecting the slitting process. Telescoping was also visible in the customer rolls which were of great length.

[0399] The new machine rolls and the new customer rolls have a smooth outer surface. In addition, the slitting process is easy and does not require any specific adjustments.

[0400] Some photos of experimental tests are as follows Figure 9a -b, where Figure 9a An example of a reference roll with 5 mm width strips and no adhesive area is shown. Figure 9b An example of a novel roll is shown having strips of uniform width and adhesive-free areas but including continuous adhesive strips that alternate in position.

[0401] The invention is not limited to the examples presented in the drawings and the above description but may be modified within the scope of the appended claims.

Claims

1. A method of manufacturing a continuous linerless label web (100), the label web (100) being arranged to be self-wound into a linerless machine roll (570), the machine roll (570) being then arranged to be unwound and longitudinally slit into narrower customer web lengths having a predetermined length and width, the customer web lengths being subsequently arranged to be self-wound into a plurality of linerless customer rolls (300), the continuous linerless label web (100) comprising a face (110) having a first side (111) and a second side (112) and an alternatingly positioned adhesive coating on the second side (112), wherein: The method comprises: providing the surface (110) with a release coating disposed on a first side (111), A continuous adhesive strip (121) is provided on the second side (112) of the web (100) in alternating positions and having a predetermined number (A) of strips in the transverse direction of the web (100), a predetermined width (B) of the strip in the transverse direction of the web (100), a predetermined position frequency (C) of the stripes in the machine direction of the web (100), and the predetermined position width (D) of the strips in the transverse direction of the web (100), The predetermined properties (A, B, C, D) of the alternating continuous adhesive strips (121) are selected so that The number of strips in each client volume (300) is one or more, The width of each strip is less than the width of each customer volume (300), and The position frequency is chosen so that one oscillation period covers 0.1-10 machine roll (570) outer circumference length, and 5-90 customer rolls (300) outer circumference length, The circumference length is defined as the length of the circumference of a complete roll, Where each customer roll has a diameter of 50-150mm, defined as the diameter of the complete customer roll, and The position amplitude of the one or more alternating adhesive stripes is in the range of 0.3-0.7 times the width of the customer roll (300).

2. The method of claim 1, wherein: The step of providing one or more alternating adhesive strips comprises: Applying the adhesive to the surface by using an oscillating actuator, thermally drying the adhesive (121) to form a pressure sensitive adhesive (120) on the surface, or The adhesive is applied to the carrier material (611) by using an oscillating actuator, the adhesive (121) is thermally dried to form a pressure-sensitive adhesive (120) on the carrier material, and the pressure-sensitive adhesive is transferred to the face.

3. The method of claim 2, wherein: The oscillating actuator includes an oscillating nozzle.

4. The method of claim 1, wherein: The step of providing one or more alternating adhesive strips comprises: Applying a continuous layer of adhesive, At least 50% of the adhesive coating (121) is removed prior to drying by using an oscillating actuator (400) to obtain one or more alternating position adhesive stripes.

5. The method of claim 4, wherein: The oscillating actuator includes a blade.

6. The method of claim 1, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation period covers a length equal to or greater than 0.4 of the machine roll circumference, and One oscillation period covers equal to or less than 6 machine roll circumference lengths, the circumference length being defined as the length of the circumference of a complete machine roll.

7. The method of claim 1, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation cycle covers a length equal to or greater than 0.8 of the machine roll circumference, and One oscillation period covers equal to or less than 6 machine roll circumference lengths, the circumference length being defined as the length of the circumference of a complete machine roll.

8. The method of claim 1, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation period covers a length equal to or greater than 0.4 of the machine roll circumference, and One oscillation period covers equal to or less than 3 machine roll circumference lengths, the circumference length being defined as the length of the circumference of a complete machine roll.

9. The method of claim 1, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation cycle covers a length equal to or greater than 0.8 of the machine roll circumference, and One oscillation period covers equal to or less than 3 machine roll circumference lengths, the circumference length being defined as the length of the circumference of a complete machine roll.

10. The method according to any one of the preceding claims 1 to 9, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation cycle covers a length equal to or greater than the perimeter of 5 customer rolls (300), and One oscillation cycle covers equal to or less than 70 customer roll (300) perimeter lengths, where the perimeter length is defined as the length of the perimeter of a complete customer roll (300).

11. The method according to any one of claims 1 to 9, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation cycle covers a length equal to or greater than the perimeter of 10 customer rolls (300), and One oscillation cycle covers equal to or less than 90 customer roll (300) perimeter lengths, where the perimeter length is defined as the length of the perimeter of a complete customer roll (300).

12. The method according to any one of the preceding claims 1 to 9, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation cycle covers a length equal to or greater than the perimeter of 10 customer rolls (300), and One oscillation cycle covers equal to or less than 70 customer roll (300) perimeter lengths, where the perimeter length is defined as the length of the perimeter of a complete customer roll (300).

13. The method according to any one of the preceding claims 1 to 9, wherein: The position wavelength (WL) of the one or more alternating position adhesive stripes is in the range of 0.5 m to 10 m.

14. The method according to any one of the preceding claims 1 to 9, wherein: The position wavelength (WL) of the one or more alternating position adhesive stripes is in the range of 2 m to 7 m.

15. The method according to any one of the preceding claims 1 to 9, wherein: The width of at least one of the one or more adhesive stripes is less than the positional amplitude of the at least one adhesive stripe.

16. The method according to any one of the preceding claims 1 to 9, wherein: The pressure sensitive adhesive coating (120) comprises a water-based acrylic adhesive.

17. The method according to any one of the preceding claims 1 to 9, wherein: The linerless label web is composed of: Surface (110), One or more alternating adhesive strips on the second side of the surface, and A release coating (130) is provided on the first side of the surface.

18. The method according to any one of the preceding claims 1 to 9, wherein: The total coverage of the adhesive coating is equal to or less than 50% based on the total area of ​​the second side (112) of the face, and / or The total coverage of the adhesive coating is equal to or greater than 10% based on the total area of ​​the second side (112) of the face.

19. The method according to any one of claims 1 to 9, wherein: The total coverage of the adhesive coating is equal to or less than 50% based on the total area of ​​the second side (112) of the face, and / or The total coverage of the adhesive coating is equal to or greater than 30% calculated based on the total area of ​​the second side (112) of the face.

20. The method of any one of claims 1 to 9, wherein: The total coverage of the adhesive coating is equal to or less than 50% based on the total area of ​​the second side (112) of the face, and / or The total coverage of the adhesive coating is equal to or greater than 40% calculated based on the total area of ​​the second side (112) of the face.

21. A linerless label web (100) obtainable by the method as claimed in any one of the preceding claims 1 to 9.

22. A linerless customer roll (300) manufactured from a continuous linerless label web (100) which has been arranged to be self-wound into a linerless machine roll (570), which has then been arranged to be unwound and longitudinally slit into narrower customer web lengths of predetermined length and width, which have then been self-wound into a plurality of linerless customer rolls, in, The linerless customer roll (300) includes a relatively narrow customer web having a face (110) having a first side (111) and a second side (112) and a continuous adhesive strip (121) alternating in position on the second side (112) of the web and having a predetermined number of strips in the cross direction of the web (A), the predetermined width of the strip in the cross direction of the web (B), the frequency of predetermined positions of the stripes in the machine direction of the web (C), and the predetermined position width (D) of the strip in the cross direction of the web, The predetermined properties (A, B, C, D) of the alternating continuous adhesive strips (121) are selected so that The number of strips in the linerless customer roll (300) is one or more, and The width of the strip is less than the width of the linerless customer roll (300), wherein the position frequency is selected so that one oscillation period covers equal to or greater than 5 customer roll (300) perimeter lengths and equal to or less than 90 customer roll (300) perimeter lengths, the perimeter length being defined as the length of the perimeter of a complete customer roll (300), Where the diameter of the customer roll is 50-150mm, defined as the diameter of the complete customer roll, and The position amplitude of the one or more alternating adhesive stripes is in the range of 0.3-0.7 times the width of the customer roll (300).

23. The linerless customer roll of claim 22, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation cycle covers a length equal to or greater than the perimeter of 5 customer rolls (300), and One oscillation cycle covers equal to or less than 70 customer roll (300) perimeter lengths, where the perimeter length is defined as the length of the perimeter of a complete customer roll (300).

24. The linerless customer roll of claim 22, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation cycle covers a length equal to or greater than the perimeter of 10 customer rolls (300), and One oscillation cycle covers equal to or less than 90 customer roll (300) perimeter lengths, where the perimeter length is defined as the length of the perimeter of a complete customer roll (300).

25. The linerless customer roll of claim 22, wherein: The frequency of the positions of the adhesive strips is chosen so that One oscillation cycle covers a length equal to or greater than the perimeter of 10 customer rolls (300), and One oscillation cycle covers equal to or less than 70 customer roll (300) perimeter lengths, where the perimeter length is defined as the length of the perimeter of a complete customer roll (300).

26. The linerless customer roll of claim 22, wherein: The position wavelength (WL) of the one or more alternating position adhesive stripes is in the range of 0.5 m to 10 m.

27. The linerless customer roll of claim 22, wherein: The position wavelength (WL) of the one or more alternating position adhesive stripes is in the range of 2 m to 7 m.

28. A linerless customer roll as claimed in any one of claims 22 to 27, wherein: The width of at least one of the one or more adhesive stripes is less than the positional amplitude of the at least one adhesive stripe.

29. A linerless customer roll as claimed in any one of claims 22 to 27, wherein: The pressure sensitive adhesive coating (120) comprises a water-based acrylic adhesive.

30. A linerless customer roll as claimed in any one of claims 22 to 27, wherein: The linerless label web is composed of: Surface (110), One or more alternating adhesive strips on the second side of the surface, and A release coating (130) is provided on the first side of the surface.

31. A linerless customer roll as claimed in any one of claims 22 to 27, wherein: The total coverage of the adhesive coating is equal to or less than 50% based on the total area of ​​the second side (112) of the face, and / or The total coverage of the adhesive coating is equal to or greater than 10% based on the total area of ​​the second side (112) of the face.

32. A linerless customer roll as claimed in any one of claims 22 to 27, wherein: The total coverage of the adhesive coating is equal to or less than 50% based on the total area of ​​the second side (112) of the face, and / or The total coverage of the adhesive coating is equal to or greater than 30% calculated based on the total area of ​​the second side (112) of the face.

33. A linerless customer roll as claimed in any one of claims 22 to 27, wherein: The total coverage of the adhesive coating is equal to or less than 50% based on the total area of ​​the second side (112) of the face, and / or The total coverage of the adhesive coating is equal to or greater than 40% calculated based on the total area of ​​the second side (112) of the face.

Images