FI128908B

FI128908B - Tyre label

Info

Publication number: FI128908B
Application number: FI20195316A
Authority: FI
Inventors: Tom Saxberg; Martti Vähälä
Original assignee: Upm Raflatac Oy
Priority date: 2019-04-18
Filing date: 2019-04-18
Publication date: 2021-02-26
Also published as: FI20195316A1

Abstract

The specification relates to a tyre label and to a method for producing a converted label web comprising the tyre labels. In the method a substrate is arranged as the release liner (310, 410, 610) or a face stock (101, 201, 501). The substrate is coated with a pressure sensitive adhesive. Longitudinal adhesive-free stripes in a machine direction of the substrate are arranged to provide incross machine direction alternating longitudinal adhesive stripes and adhesive-free stripes. A coating thickness profile variation B in cross machine direction of the adhesive stripes is arranged to be smaller than +/- 15 %. A distance C between an upper and a lower edge of a transition area between the adhesive stripe and the adhesive-free stripe is arranged to have a maximum width of 2 mm in the cross machine direction. The release liner (310, 410, 610) is laminated together with the face stock (101, 201, 501) in such a way that the pressure sensitive adhesive is arranged in between the face stock (101, 201, 501) and the release liner( 310, 410, 610) to form a label laminate web. The label laminate web is die-cut to form a converted label web, wherein the converted label web comprises the release liner (310, 410, 610) with tyre labels (100, 200, 300, 500, 600) attached onto it. A face (101, 201, 501) of a tyre label has a first section (201a), the first section comprising an adhesive area (204). The face (101, 201, 501) further comprises a second section (201b) contiguous to the first section (201a), the second section (201b) including an adhesive-free finger tab (203, 503), and a turn between the first section (201a) and the second section (201b) is arcuate.

Description

Tyre label Technical field This specification relates to a tyre label and to a method for producing a converted label web comprising the tyre labels. Background Labels disclosing information on for example tyre products, logistics or performance and/or environmental properties of the tyres can be applied on tread surfaces of tyres in different phases of the tyre manufacturing or logistic processes. Occasionally, the labels have to be removed during the manufacturing process or at some later phase, for example when providing studs onto the tread surface. After studding, the tyre must again be labelled. Finally, upon installing a tyre onto a vehicle, the labels need to be removed. It is preferable that the tyre label is easily removable, and it should preferably not leave any adhesive residues onto the tread surface of the tyre.

US 2003039786 A1 discloses a pressure sensitive adhesive, an adhesive label having a non-adhesive portion and a process for configuring said labels for use in a food safety labelling system. US 2005194090 A1 discloses adhesive labels for use in food safety labelling systems. EP 0514625 A2 discloses a method of producing a label with adhesive-free lifting portion. US 6238760 B1 discloses pull tab labels for match mounting a tyre with a rim.

N Summary

N S It is an aim of this application to provide a fast, efficient and inexpensive 3 30 method for producing a converted label web comprising tyre labels as well as I the tyre label containing an adhesive-free finger tab allowing an easy, residual- o free removal of the tyre label from the tread surface of the tyre.

2 O According to an embodiment, a method for producing a converted label web N 35 comprising a release liner with tyre labels attached onto it is provided. The method comprises the steps of:

- arranging a substrate as the release liner or a face stock and coating the substrate with a pressure sensitive adhesive, - providing longitudinal adhesive-free stripes in a machine direction of the substrate to provide in cross machine direction alternating longitudinal adhesive stripes and adhesive-free stripes, - arranging a coating thickness profile variation B in cross machine direction of the adhesive stripes to be smaller than +/- 15 %, - arranging a distance C between an upper and a lower edge of a transition area between the adhesive stripe and the adhesive-free stripe to have a maximum width of 2 mm in the cross machine direction, - laminating the release liner together with the face stock in such a way that the pressure sensitive adhesive is arranged in between the face stock and the release liner to form a label laminate web, - die-cutting the label laminate web to form a converted label web, wherein the converted label web comprises the release liner with tyre labels attached onto it, wherein o a face of a tyre label has a first section, the first section comprising an adhesive area, o the face further comprises a second section contiguous to the first section, the second section including an adhesive-free finger tab, o a turn between the first section and the second section is arcuate, o the first section further comprises at least one adhesive-free area along length of at least one edge of the tyre label, and N o the adhesive-free finger tab is arranged as an extension of the N at least one adhesive-free area.

S S 30 According to another embodiment, a tyre label comprising a face and an I adhesive layer adjoined to the face is provided. The adhesive layer comprises o pressure sensitive adhesive. The face has a first section, the first section mn comprising an adhesive area. The face further comprises a second section 3 contiguous to the first section, the second section including an adhesive-free finger tab. A coating thickness profile variation B of the adhesive area is smaller than +/- 15 %. A distance C between an upper and a lower edge of a transition area between the adhesive area and the adhesive-free finger tab has a maximum width of 2 mm, and a turn between the first section and the second section is arcuate. The first section further comprises at least one adhesive- free area along length of at least one edge of the tyre label, and the adhesive- free finger tab is arranged as an extension of the at least one adhesive-free area. Further embodiments are presented in the dependent claims. Brief description of the drawings Fig. 1 illustrates, by way of an example, a side view in the Sx,Sz-plane of a tyre label 100 according to an embodiment, Fig. 2a illustrates, by way of an example, a top side view in the Sx,Sy- plane of a tyre label 200 according to an embodiment, Fig. 2b illustrates, by way of an example, an underside view in the Sx,Sy- plane of a tyre label 200 according to an embodiment, Fig. 3a illustrates, by way of an example, a top side view in the Sx,Sy- plane of a converted label web according to an embodiment, Fig. 3b illustrates, by way of an example, a top side view in the Sx,Sy- plane of a converted label web according to an embodiment, Fig. 4 illustrates, by way of an example, a side view in the Sx, Sz-plane N of a release liner coated with adhesive according to an N embodiment,

S S 30 Fig. 5 illustrates, by way of an example a top side view in the Sx,Sy- x plane of a tyre label 500 according to an embodiment, and

O n Fig. 6 illustrates, by way of an example, a top side view in the Sx,Sy- 3 plane a converted label web according to an embodiment. & 35 The figures are schematic. The figures are not in any particular scale.

Detailed description The solution is described in the following in more detail with reference to some embodiments, which shall not be regarded as limiting.

In this description and claims, the percentage values relating to an amount of a material are percentages by weight (wt.%) unless otherwise indicated. Term “comprising” may be used as an open term, but it also comprises the closed term “consisting of”. Unit of thickness expressed as microns corresponds to um. Unit of temperature expressed as degrees C corresponds to °C. The following reference numbers and denotations are used in this application: Sx, Sy, Sz 3D coordinates MD machine direction CD cross (machine) direction PSA pressure sensitive adhesive A center area B coating thickness profile variation C distance phr parts per hundred rubber/resin 100 tyre label 101 face, face stock 102 adhesive layer 200 tyre label 201 face, face stock = 201a first section N 201b second section N 203 adhesive-free finger tab 2 30 204 adhesive area I 205 adhesive-free area + 300 tyre label = 310 release liner S 402 adhesive layer > 35 410 release liner 500 tyre label 501 face, face stock

503 adhesive-free finger tab 600 tyre label 610 release liner 5 A label is a piece of material to be applied onto articles of different shapes and materials.

A label comprises at least a face material also referred to as a face stock or a face.

A typical way to adhere the label onto an article is by use of adhesive.

The label comprising an adhesive layer is referred to as an adhesive label.

The adhesive may comprise pressure sensitive adhesive.

A label comprising pressure sensitive adhesive may be referred to as a pressure sensitive adhesive (PSA) label.

Pressure sensitive adhesive labels may also be referred to as self-adhesive labels.

The labelled article may be for example a tyre.

The surface to be labelled may be a tread surface of a tyre.

Term “face” refers to a top substrate of the label, also called as a face stock or a face material.

In case of a plastic face material it may also be called a face film.

The face may have a monolayer or multilayer structure comprising at least two layers.

A multilayer structure may have been composed by laminating several pre-formed layers together or by coating one or more layers onto a base material.

In case of a plastic material the multilayer filmic structure may also be formed by co-extrusion.

The face is the layer that is adhered to the surface of an article during labelling through an adhesive layer.

A combination comprising a face and adhesive may be referred to as an adhesive label.

The face may comprise e.g. printing in order to provide information and or visual N effect.

The face may be printed in two phases.

Further, the label may contain N additional layers, for example top coatings or overlaminates to protect the top S surface and/or print of the label against rubbing or other external stress.

S 30 I Term “release liner” refers to a structure comprising a substrate and a release c layer on a surface of the substrate contacting the adhesive in a label laminate. mn The substrate may also be called a backing material.

The release liner may 3 comprise a release agent.

The release agent is a chemical having low surface tension.

The release agent may be used in order to prevent other materials from bonding to it and to provide a release effect.

Release liners of the label laminates may serve one or more useful functions: they may be used as a carrier sheet onto which the adhesive is coated; they may protect the adhesive layer during storage and transportation; they may provide a support for labels during die-cutting and printing, and ultimately they may provide the release substrate carrying the labels for dispensing onto the items to be labelled.

Term “label laminate”, also referred to as an adhesive label laminate refers to a product comprising a face, adhesive and a release liner. In the label laminate the face is laminated together with the release liner having the adhesive in between. The label laminate may be a continuous structure from which the individual labels may be die-cut. The release liner of the label laminate is typically removed prior to labelling i.e. attaching the label onto the surface of an item to be labelled. Individual labels may be cut from the label laminate structure. After cutting, the labels may remain to be attached to a common release liner (the release liner remains uncut). Thus, a plurality of labels may remain to be attached to a common continuous release liner. This may be called a converted label web. Alternatively, the labels may be completely separate (i.e. also the release liner may be cut). A label, including a face and adhesive, may be separated from the release liner e.g. by pulling the release liner in the direction -S7 with respect to the label. Thus, a surface of the adhesive layer is exposed so that said surface can be attached to an article. Term “web” refers to a continuous sheet of material. The web is generally processed by moving over rollers. Between processing stages, webs may be stored and transported as rolls.

N N Term “machine direction” refers to manufacturing direction of a web. Machine S direction may also refer to a circumferential direction of a roll. Term “cross 3 30 machine direction” or “cross direction” refers to a direction that is transversal x to the machine direction.

O mn Term “laminate web” refers to a structure comprising two or more continuous 3 sheets of material attached together into a web format. Typically, the laminate web comprises a face material attached (laminated) onto a release liner via a pressure sensitive adhesive.

Typically a label laminate web is manufactured as a continuous web with the original width of the label laminate web corresponding to the width of the manufacturing/laminating machine. This manufacturing width may be, for example, 0.3-3 meters and corresponds therefore to the width of the so-called machine rolls that are created in the end of the lamination process. Then, the machine rolls are slit, i.e. cut lengthwise to so-called customer rolls with smaller widths ranging from a few centimeters typically to some tens of centimeters depending on the end use. The slitting involves typically unwinding the machine roll, then slitting the web and again winding the narrower webs into individual customer rolls. Alternatively, the slitting into customer rolls may be performed as a part of the label lamination process as an in-line process, or it may be even performed as a part of the label laminate converting process, where the label laminate is further die-cut (kiss cut) to form individual labels carried by continuous release liner. Printing and other converting steps may be performed on suitable process phases, as known in the art. The current disclosure involves a step, wherein a label laminate web is arranged to comprise longitudinal adhesive stripes and adhesive-free stripes in machine direction, i.e. in the manufacturing direction of the web. The adhesive-free stripe is a continuous area arranged in machine direction of the label laminate web. This adhesive-free stripe is important for providing an adhesive-free finger tab of a tyre label according to the disclosure. Further, the end use places demands on the positional accuracy of the adhesive-free stripe, which demands arise partly from the following converting steps of the label laminate web where, for example, the die-cutting needs to be accurately positioned and aligned with respect to the adhesive-free stripe which has been N arranged into the laminate during previous manufacturing steps.

N S The longitudinal adhesive-free stripes of the label laminate web are obtained 3 30 by pattern gumming. As a result, a pattern gummed label laminate web is I obtained. Pattern gumming refers to a manufacturing technique, wherein o before lamination of the label laminate web the adhesive is only locally coated e onto a substrate, the substrate being the release liner or the face stock, or 3 alternatively the adhesive is locally removed from certain areas of the substrate before lamination with the face material or the release liner thereafter.

One option for providing adhesion-free stripes would be to treat the adhesive layer locally to lose its tack, for example by varnishing the adhesive layer locally or by using some other appropriate chemical treatment. However, this would require an extra step in the manufacturing process. Further, treating the adhesive locally to lose its tack might increase the risk of bleeding of the adhesive and/or cause problems in the slitting because of the lack of an area at the edge of the web without adhesive. Thus, within context of this disclosure, the adhesive-free stripes are provided by coating the adhesive only locally or by removing the adhesive before lamination.

The adhesive may be coated in any manner known in the art. However, it must be ensured that a transition in the cross machine direction from the adhesive- free stripes to the adhesive stripes is as sharp and stepwise as possible and that the adhesive stripes have an even thickness profile in cross machine direction. It would be possible to coat the adhesive by printing methods. However, such methods are often slow, complex and require special equipment. Within context of this disclosure, a fast, efficient and inexpensive method that enables a production from a roll to roll is desired.

The adhesive may be coated using a slot die coating method. For pattern gumming, the slot die coating method may be modified in such a way, that the slot die nozzle comprises external adhesive flow blocking units to provide pattern gumming capability. The blocking units are designed to correspond to the predetermined adhesive-free stripe widths and shaped to provide an adhesive flow that ensures even adhesive coating profile at adhesive coated stripes. The modified slot die including the blocking units may be designed by N taking into account the speed of the web and the fluidic properties of the N adhesive to be coated. As an alternative to the modified slot die including the S blocking units, the adhesive may be applied on the entire width of the release 3 30 liner or the face stock by a slot die, and then locally removed from the areas I intended to be adhesive-free (i.e. adhesive-free stripes). The adhesive may be o removed by a doctor blade (wiping blade).

2 O Alternatively, the adhesive may be coated using a roll or bar coater, wherein N 35 the adhesive is applied on the entire width of the release liner or the face stock. After that, the adhesive is locally removed from the areas intended to be adhesive-free (i.e. adhesive-free stripes). The adhesive may be removed by a doctor blade (wiping blade).

Yet alternatively, the adhesive may be coated using a curtain coater, wherein the adhesive is applied as a curtain of fluid falling onto the release liner or the face stock. After producing an even coat on the entire width of the release liner or the face stock, the adhesive is locally removed from the areas intended to be adhesive-free (i.e. adhesive-free stripes). Again, the adhesive may be removed by a doctor blade (wiping blade).

Typically, the adhesive is coated onto the substrate in liquid phase and afterwards “solidified” into pressure sensitive adhesive layer. This “solidification” may be performed by heat treating the adhesive layer to remove water in case of water based adhesives, or by removing solvents in case of solvent based adhesives. Further, the solidification may include chemical cross-linking reactions to cure the adhesive layer into pressure sensitive adhesive. In case of hot melt adhesives, the “solidification” takes place when the adhesive layer cools down.

In case of hot melt adhesive the adhesive is in principle 100% solid. No water/solvent is comprised in the hot melt adhesive. During the manufacturing process of the label laminate web the hot melt adhesive is melted and pumped in its molten state to a coating head or roll. From the coating head or roll the molten adhesive is transferred onto the release liner or the face stock to form the adhesive layer.

N The transition between adhesive-free and adhesive coated stripes in cross N machine direction is schematically shown in Fig. 4 together with the definition S of the thickness profile variation of the adhesive coated stripes compared to 3 30 the average thickness of the adhesive. These are described in more details x below with reference to Fig. 4.

O mn According to an embodiment, the thickness profile variation B in cross machine 3 direction of the adhesive coated stripes is smaller than +/- 15 %, preferably being no more than +/- 10 % or even less than +/- 5 % when compared to the average thickness of the stripe measured at a center area A of the adhesive stripe in cross machine direction. The average thickness may be defined, for example, averaging the thickness over an area corresponding to 20, 40, 60 or 80 % of the total width of the adhesive stripe in cross machine direction and centered onto the adhesive stripe width.

An area between the adhesive stripe and the adhesive-free stripe is called a transition area. At an edge of the adhesive stripe, wherein the thickness of the adhesive stripe falls below 80 % of the average coating thickness, this is considered to indicate an upper edge of the transition area. A lower edge of the transition area is indicated wherein the adhesive thickness falls below 20 % of the average coating thickness. The stepwise transition area in cross machine direction calculated as the distance C between the upper and lower edges of the transition areas has maximum width of 2 mm in the cross machine direction. Preferably, the distance C is not wider than 1 mm. According to an embodiment, a width and/or positional accuracy of the adhesive-free stripe in cross machine direction is + 2.0 mm, preferably + 1.0 mm. This means that the width and/or position of the adhesive-free stripe along longitudinal length of the substrate when measured from distinct locations does not deviate more than + 1.0 mm, preferably not more than + 0.5 mm. Thus, an accuracy of the pattern gumming in cross machine direction is at least +2.0mm, preferably at least + 1.0 mm. As arule of thumb, the adhesive coating thickness is related to the coat weight of the adhesive in such a way, that generally coat weight of 1 g/m? corresponds N to coating thickness of ~ 1 um or slightly less.

N S According to an embodiment, the average coating thickness of the adhesive is 3 30 50 um. More specifically, the average coating thickness may be 52 um in case I of filmic face material, and 48 um in case of paper-based face material. The o adhesive may have a tack of from 12 to 25 N/25 mm on rubber, measured mn according to a modified FINAT FTM9 standard. The peel (90°, 3 min) value of 3 the adhesive on rubber may be of from 15 to 32 N/25 mm, when measured according to a modified FINAT FTM2 standard. The solution having a higher average coating thickness of the adhesive is preferred for labels to be dispensed manually.

According to another embodiment, the average coating thickness is 35 um. The adhesive may have a tack of from 10 to 20 N/25 mm on rubber, measured according to a modified FINAT FTM9 standard. The peel (90°, 3 min) value of the adhesive on rubber may be of from 12 to 25 N/25 mm, when measured according to a modified FINAT FTM2 standard. According to yet another embodiment, the average coating thickness is 27 um. Expression “modified” here in relation to FINAT FTM9 and FINAT FTM2 standards and tack and peel parameters therein is used to emphasize that a rubber test surface has been used instead of the standard float glass surface. Further, in FINAT FTM2 peel test interval of 3 minutes has been used instead of standard 20 minutes interval between adhering the adhesive strip on rubber test surface and testing.

The tack and peel (90*) values for adhesive within context of this disclosure have been measured using a rubber test surface having the following ingredients (unit = phr): PLF 1723 SBR 110.00 BUD 1207 BR 20.00 N299 Carbon Black 60.00 Zeosil 1165MP Silica 5.00 Naphthenic Oil 7.75 VANWAX H 3.80 Polystay 100 1.15 N Stearic Acid 2.00 N Zinc Oxide 1.75 S Sulfur 1.70 3 30 DURAX® 1.70 x DPG 0.25

O n Total 215.10 3 The solution having a lower average coating thickness of the adhesive is preferred for labels to be dispensed automatically. The high coating thickness may cause problems in automatic labelling especially at high temperatures because of bleeding of the adhesive. In a case the label is printed in a two- phase process, the printing in the second phase may be effected by bleeding of the adhesive, which may cause the adhesive to get in contact with thermal transfer ribbon, thus causing severe problems in the printing process.

Within context of this disclosure, the pressure sensitive adhesive is removable adhesive, i.e. it can be peeled manually after having been attached onto the surface to be labelled. For removable adhesive, it is characteristic that the peeling force does not grow to unacceptable levels even after longer period of having been adhered to a labelled surface. Further, the removable adhesive of this application should be such that it can be clean peeled, i.e. leaving minor or negligible residues on the surface having been labelled onto. The label laminate web according to this disclosure is configured to be converted before dispensing the individual labels. The conversion refers to processes such as printing, coating, die-cutting and slitting. During conversion the label laminate web is converted to an intermediate product, namely a converted label web. The converted label web refers to a product wherein individual labels remain to be attached onto a release liner, which is used as a carrier in later phases to help to carry and dispense the individual labels to their final use. The label laminate web as presented above is die-cut in order to obtain individual labels attached on a continuous release liner. In die-cutting the labels are cut into a desired shape. Die-cutting is arranged to cut the face stock and the pressure sensitive adhesive layer adjoined to it. Waste material (i.e. N waste matrix) that does not belong to the labels is removed.

N S For die-cutting, it is of importance to have proper thickness and viscoelastic 3 30 properties for the adhesive layer, such that no bleeding of the adhesive I happens during the die-cutting or afterwards when the web has been rolled o into a label web roll. Bleeding of the adhesive may cause unwanted adhesive mn residues either or both on the edges of the label and on the die-cutting tool. In 3 a converted label web roll the laminate structure within the labels will experience pressure due to the tightness of the roll and this may cause further adhesive bleeding effects. Adhesive residues on the edges of the label may cause labels to stick unwantedly or cause unwanted contamination of the machine parts becoming in contact with the web/label, which might cause for example expensive downtimes in dispensing processes and also affect the end use properties.

Tyre labelling presents challenges with respect to label properties. The roughness of the labelled substrate as well as the chemical composition of the tyre rubber represent the origin of the challenges. The contact area between the label and the tread surface of the tyre is rather small because of the uneven tyre profile, and thus very aggressive and immediate adhesion is required.

Once labelled, the storage and transporting conditions for tyres may vary from room temperature to warmer or colder conditions in warehouses or outdoors. Accordingly, the tyre label and its adhesive layer must maintain their properties in low and high (alternating) temperatures, and occasionally for long periods of time.

According to an embodiment and as illustrated in Figs. 1, 2a and 2b a tyre label 100, 200 is provided. The tyre label 100, 200 comprises a face 101, 201 and an adhesive layer 102 adjoined to the face 101, 201. The adhesive layer 102 comprises a pressure sensitive adhesive.

Fig. 2a illustrates a top side view in the Sx, Sy-plane of a tyre label 200 and Fig. 2b illustrates an underside view in the Sx,Sy-plane of a tyre label 200. As shown in Figs 2a and 2b the face 201 of the tyre label 200 has a first section 201a and a second section 201b. The first section 201a comprises an adhesive area

204. The first section 201a may further comprise at least one adhesive-free area 205 along length of at least one edge of the tyre label 200. The second N section 201b is integrated to the first section 201a of the face 201. Thus, the N second section 201b is contiguous to the first section 201a. The second S section 201b includes an adhesive-free finger tab 203. The adhesive-free 3 30 finger tab 203 may be rounded in shape. The adhesive-free finger tab 203 may I be arranged as an extension of the adhesive-free area 205, as illustrated in o Fig. 2b. A junction (i.e. turn) between the first section 201a and the second 3 section 201b is arcuate. > N 35 Correct design, placing/location and size of the adhesive-free finger tab 203 is important for the desired end use in tyre labelling. The design of the finger tab must allow a proper manual grab when removing the label. The design of the finger tab edges is preferably rounded in order to avoid sharp corners that might promote tearing when peeling the label from the surface of the tyre. For the same reason, especially the junction between the adhesive-free finger tab and the edge of the tyre label that extends to the finger tab is preferably rounded, such that an arcuate turn between the adhesive-free finger tab and the adhesive-free area is provided.

According to an embodiment, a minimum radius of curvature in the stem area (i.e. the arcuate turn) is larger than 1 millimeters, preferably larger than 2 millimeters. The minimum radius of curvature is dependent on the face material of the label. A higher radius of curvature is required for a face that is thinner and more susceptible to tearing, than for a face that is thicker and thus less susceptible to tearing.

Shape of the first section 201a of the face may be one of the following: a quadrangle, a round, a semicircle or an ellipse. In a case the shape is quadrangular, the adhesive-free finger tab 203 may be arranged on at least one corner of the quadrangular first section, such that a length of a release front of the label when peeling off the label is minimized. The adhesive-free finger tab 203 may be arranged slantwise on a corner of the first section 201a. In principle, the shape of the first section 201a may be freely selected, but in view of the effective usage of the label laminate area and die-cutting to minimize the amount of waste matrix material, and in order to provide maximum area for printed information, uncomplicated shapes may be preferred.

N Size of the adhesive-free finger tab 203 must be chosen such that a proper N grab is allowed. However, unnecessary large size of the tab should be avoided, S as the unattached, free-moving adhesive-free tab may effect usability of the 3 30 label. Length of the adhesive-free finger tab 203 is preferably smaller than the I length of the edge of the label to which the adhesive-free finger tab 203 is c contiguous to.

0 O Arranging the adhesive-free finger tab 203 as an extension of the adhesive- N 35 free area 205 provides the effect that when peeling the label away from the receiving surface, i.e. the tyre surface, the tear resistance of the label may be increased, as the surface to which the peeling force affects is increased.

Fig. 5 illustrates an exemplary view of a tyre label 500 according to an embodiment, wherein the adhesive-free finger tab has been arranged slantwise on a corner of the first section of the face 501. A direction of separation when peeling the tyre label 500 by grabbing the adhesive-free finger tab 503 is illustrated by the bolded arrow.

The dashed lines illustrate the line of separation when removing the label.

It is desired that in the beginning of removal of the label, i.e. when the label starts to become separated from the labelled item, the length of the line of separation is as short as possible.

The length of the line of separation then grows, until becomes constant at the final phase of the separation.

The length of the line of separation may be controlled by the tearing away direction.

The adhesive-free finger tab is configured to guide the user in order to obtain the optimal separation direction for the label.

As illustrated by Fig. 5, the label 500 may be provided with a cut corresponding to the adhesive-free finger tab of the successive label in machine direction of the converted label web.

In this manner, the usage of the materials may be optimized and thus waste of the materials minimized.

The first section 201a of the face 101, 201 may comprise two adhesive-free areas 205 along lengths of two opposing edges of the tyre label 100, 200, 300. In that case the adhesive area 204 is located between the two adhesive-free areas 205 along lengths of the two opposing edges.

This arrangement provides the effect that bleeding of the adhesive especially in die-cutting may be prevented and thus unwanted adhesive residues either or both on the edges of the label and on the die-cutting tool may be avoided.

Further, two N adhesive-free areas along lengths of two opposing edges of the tyre label also N have an effect on preventing bleeding of the adhesive of the converted label S web havina been rolled onto a customer roll.

Bleeding of the adhesive can 3 30 make opening of the customer roll, and thus dispensing of the tyre labels I difficult and time-consuming.

Further, the face 101, 201 may comprise two o adhesive-free finger tabs 203 arranged as extension of the adhesive-free e areas 205. 3 Wax or silicone-based chemicals used as mould release agents during the tyre manufacturing process are often present in the tyres to be labelled.

This provides special demands for the tyre label.

The face and the adhesive of the label must withstand the migration of chemical components from the tyre material. These components may for example cause the label to yellow if the labelling materials are not resistant to migration. The migrating components of the tyre material may also have an impact on the adhesive layer, for example weakening the adhesive anchorage or altering the clean peel properties. According to an embodiment, the face 101, 201, 501 of the tyre label 100, 200, 300, 500, 600 is configured to act as a barrier preventing migration of components of a tyre and/or the adhesive layer through the label. The face 101, 201, 501 may comprise paper-based material, polyester or polypropylene.

The paper-based material may comprise aluminium, the function of which is to provide the desired barrier properties to the face 101, 201, 501. The paper- based material comprising aluminium also has the desired stiffness and conformability that is needed for the tyre label 100, 200, 300, 500, 600. Conformability of the label is important when labelling an uneven surface of a tyre.

Choice of the face material is important for the end use in tyre labelling. The face has to have a good tear resistance. In end use, the tyre label may be dispensed either manually or automatically, and proper stiffness of the face material is important especially from the automatic dispensing point of view in order to ensure that face material can be easily and reliably separated from the backing material when the web is run over a dispensing tip. Also, low elongation in MD is a desired property of the face material helping both N dispensing and removal of the label and keeping the printed information in its N original dimensions. In a case the face material is plastic film, the face is S preferably biaxially oriented. The face is preferably configured to show no 3 30 deformation when removing the label from the labelled surface.

= c Also the pressure sensitive adhesive has to have certain properties in order to mn best serve the end use of the labels in tyre labelling. The adhesive has to have 3 a high tack. The tack of the adhesive on rubber may be from 10 to 25 N/25 mm, preferably from 10 to 20 N/25 mm or from 12 to 25 N/25 mm. Also, a high coat weight is desired. The coat weight of the adhesive may be from 20 to 60 g/m?, preferably from 25 to 35 g/m? or from 45 to 55 g/m?. The cohesion of the adhesive layer has to be sufficient in order to prevent cleavage of the adhesive layer when detaching the label from the tyre surface. Further, the anchorage of the adhesive to the face must be sufficient enough, such the adhesive layer remains with face when detaching the label, and no adhesive residues remain on the tyre surface. For the end use in tyre labelling, the adhesive has to show pressure sensitivity on a predetermined temperature range from -20 to 60 °C. For example in transporting the tyres may be exposed to alternating temperatures and it is of importance that also the tyre labels withstand those temperatures without losing for example the adherence properties. According to an embodiment, the face 101, 201, 501 of the tyre label 100, 200, 300, 500, 600 comprises two adhesive-free areas 205 along lengths of opposite edges of the tyre label 100, 200, and two adhesive-free finger tabs 203, 503 arranged as extension of the adhesive-free areas 205. In a case the shape of the first section 201a is quadrangular, the adhesive-free finger tabs 203, 503 may be arranged on transversal corners of the quadrangular first section. Again, the adhesive-free finger tabs 203, 503 may be arranged slantwise on the corners of the first section 201a. The tyre labels within context of this disclosure are obtainable by performing the die-cutting of the labels on exactly correct position with respect to the pattern gummed label laminate web. The adhesive-free finger tabs 203, 503 and optionally the adhesive-free areas 205 are to be located on the adhesive- free stripes of the label laminate web in die-cutting. The adhesive areas 204 N are to be located on the adhesive stripes of the label laminate web.

N S According to an embodiment, a method for producing a converted label web 2 30 comprising a release liner 310, 610 with tyre labels 100, 200, 300, 500, 600 I attached onto it, as illustrated in Figs. 3a, 3b and 6 is provided. Top side views o in the Sx, Sy-plane of a release liner 310, 610 with tyre labels 300, 600 attached 3 onto it is illustrated in Figs. 3a, 3b and 6. > N 35 In the method a substrate is arranged as a release liner 310, 610 or a face stock 101, 201, 501. The substrate is coated with a pressure sensitive adhesive. Longitudinal adhesive-free stripes in a machine direction of the substrate are provided. As a consequence, the release liner 310, 610 or the face stock 101, 201, 501 is provided with in cross machine direction alternating longitudinal adhesive stripes and adhesive-free stripes. A coating thickness profile variation B in cross machine direction of the adhesive stripes is arranged to be smaller than +/- 15 %. A distance C between an upper and a lower edge of a transition area between the adhesive stripe and the adhesive- free stripe is arranged to have a maximum width of 2 mm in the cross machine direction. The release liner 310, 610 is laminated together with the face stock 101, 201, 501 in such a way that the pressure sensitive adhesive is arranged in between the face stock 101, 201, 501 and the release liner 310, 610. Thus, a label laminate web is formed. The label laminate web is die-cut to form a converted label web, wherein the converted label web comprises the release liner 310, 610 with tyre labels 100, 200, 300, 500, 600 attached onto it. A face 101, 201, 501 of a tyre label has a first section 201a, the first section comprising an adhesive area 204. Optionally, the face 101, 201, 501 further comprises at least one adhesive-free area 205 along length of at least one edge of the tyre label 100, 200, 300, 500,

600. The face 101, 201, 501 further comprises a second section 201b contiguous to the first section 201a, the second section 201b including an adhesive-free finger tab 203. Optionally, the adhesive-free finger tab 203, 503 is arranged as an extension of the at least one adhesive-free area 205. The turn between the first section 201a and the second section 201b is arcuate. Die-cutting of the label laminate web may be performed in various ways. According to an embodiment illustrated in Fig. 3a the label laminate web may N be die-cut in such a way that the adjacent and successive labels in the machine N direction of the resulting converted label web are uniformly oriented. The S adhesive-free finger tabs of the labels may be arranged to be on a trailing 3 30 portion of the label in the machine direction of the web. In Fig. 3a this refers to I a situation, wherein the machine direction of the converted label web is the Sx- c direction. Alternatively, the adhesive-free finger tabs of the labels may be mn arranged to be on a leading portion of the label in the machine direction of the 3 web. In Fig. 3a this refers to a situation, wherein the machine direction of the converted label web is the -Sx-direction.

Alternatively, the label laminate web may be die-cut in a manner illustrated by Fig. 3b.

In that case, the adhesive-free finger tabs of two adjacent labels are arranged to extend to opposite directions in the cross machine direction of the converted label web.

In this way, the spacing of the labels is more efficient, and the consumption of materials may be decreased and generation of waste material minimized.

According to an embodiment, the labels 600 may be arranged to be die-cut as illustrated in Fig. 6. In that case, the adjacent longitudinal lines of the labels 600 on the release liner 610 in the machine direction are arranged in an interlocked manner.

This provides the effect that pressure affecting on die- cutting may be reduced, as the total length of the die-cutting line at a given moment of time is decreased, as shown in Fig. 6. The grey areas of Fig. 6 illustrate the locations wherein the die-cutting pressure at a given moment of time affects.

For comparison, the situation according to Fig. 3b is illustrated by dashed lines.

Face materials The face of the tyre label may comprise paper-based material, polyester or polypropylene.

In an example, the face is a white, biaxially oriented polypropylene film.

The face has a thickness of 92 um and a grammage of 90,1 g/m?. The face has a tensile strength in MD of 180 MN/m? and tensile strength in CD of 170 MN/m?, when measured according to ASTM D 882 standard.

The face has an N elongation at break in MD of 110 % and elongation at break in CD of 120 %, N when measured according to ASTM D 882 standard.

The face has a 1% S modulus in MD of 2000 MN/m? and 1% modulus in CD of 1900 MN/m?, when 3 30 measured according to ASTM D 882 standard. = c In an example, the face is a white, cavitated, biaxially oriented polypropylene n film.

The face has a thickness of 60 um and a grammage of 45,4 g/m?. The 3 face has a tensile strength in MD of 95 MPa and tensile strength in CD of 185 MPa.

The face has an elongation at break in MD of 170 % and elongation at break in CD of 55 %. The face has a 1% modulus in MD of 1600 MPa and in

CD of 2600 MPa. The face has a tensile strength at break in MD of 95 MPa and tensile strength at break in CD of 185 MPa.

Adhesive layer The adhesive layer of the tyre label comprises pressure sensitive adhesive. Within context of this disclosure, the pressure sensitive adhesive may be acrylic-based or rubber-based. Acrylic adhesives are based on acrylic polymers, which are a type of synthetic polymer which fall into the thermoplastic resin family. Rubber-based adhesives can be made of synthetic rubber or natural rubber. The adhesive may have a carrier that in water-based adhesives (dispersions) is water. In solvent-based adhesives the carrier is other solvent than water. As already mentioned above, hot melt adhesives are typically 100% solids, meaning that no solvents have been used in them. The pressure sensitive adhesive may be a rubber-based hot melt pressure sensitive adhesive. Alternatively, the pressure sensitive adhesive may be an acrylic-based UV hot melt adhesive. In that case the hot melt adhesive comprises a photoinitiator for crosslinking of the adhesive by UV light.

In an example, the hot melt pressure sensitive adhesive comprises thermoplastic elastomer. The thermoplastic elastomer may comprise a styrene block polymer. The styrene block polymer may be at least one of the following: styrene and styrene-butadiene copolymer (SBS, SBR), styrene-isoprene copolymer (SIS), styrene-ethylene/butylene copolymer (SEBS), styrene- ethylene/propylene-styrene copolymer (SEPS) or styrene-isoprene-butylene copolymer (SIBS). The amount of thermoplastic elastomer may be from 5 to N 50 wt.% of the hot melt pressure sensitive adhesive.

N S In an example, the hot melt pressure sensitive adhesive comprises at least 3 30 one tackifying resin as an additional component. The amount of the tackifying I resin may be from 20 to 70 wt. %, preferably from 30 to 60 wt.%. In particular c this concerns resins with a softening point from 70 to 130 °C, when measured 3 by a ring and ball method according to standard DIN 52011. The tackifying O resin may comprise hydrocarbon, rosin ester or terpene resin. The N 35 hydrocarbon resin may comprise at least one of the following: aromatic, aliphatic, petroleum or cycloaliphatic hydrocarbon resin, or modified or hydrogenated versions thereof.

In an example, the hot melt pressure sensitive adhesive comprises at least one plasticizer. The plasticizer may be used to adjust the viscosity, provide an improved processability and if needed increase the tack of the mixture. The viscosity of the plasticizer may be between 10 to 1500 mPas at 25 °C, in particular between 100 and 600 mPas (measured according to standard DIN 1342). The plasticizer may be comprised in the pressure sensitive hot melt adhesive in a concentration of 5 to 40 wt.%, preferably in a concentration of from 10 to 30 wt.%. Suitable plasticizers comprise medicinal white oils, naphthenic mineral oils, adipates, polypropylene oligomers, polybutene oligomers, polyisoprene oligomers, hydrogenated polyisoprene and/or polybutadiene oligomers, benzoate esters, vegetal or animal oils and their derivatives, sulfonic acid esters, mono or polyhydric alcohols, polyalkylene glycols having a molecular weight of from 200 to 6000 g/mol, such as polypropylene glycol or polybutylene glycol. In particular, oily plasticizer components may be added. The plasticizer component is preferably a liquid at room temperature. In an example, the hot melt pressure sensitive adhesive may comprise minor amount of a wax. The wax may be of natural or synthetic origin, and it may be chemically modified. The amount of the wax may be less than 10 wt.%. The amount of wax should be such that it does not negatively influence the adhesion. In an example, the hot melt pressure sensitive adhesive may comprise typical auxiliaries and/or additives. Examples of these are stabilizers, antioxidants N such as sterically hindered phenols, phosphites or thioesters, colorants such N as titanium dioxide, fillers such as talcum or clay, or coupling agents. Additives S and/or auxiliaries may be comprised by the hot melt pressure sensitive 3 30 adhesive in quantities up to 5 wt.%, preferably in quantities of about 3 wt. %. i © 3

N

Claims

Claims:

1. A method for producing a converted label web comprising a release liner (310, 410, 610) with tyre labels (100, 200, 300, 500, 600) attached onto it, the method comprising the steps of: - arranging a substrate as the release liner (310, 410, 610) or a face stock (101, 201, 501) and coating the substrate with a pressure sensitive adhesive, - providing longitudinal adhesive-free stripes in a machine direction of the substrate to provide in cross machine direction alternating longitudinal adhesive stripes and adhesive-free stripes, - arranging a coating thickness profile variation B in cross machine direction of the adhesive stripes to be smaller than +/- 15 %, - arranging a distance C between an upper and a lower edge of a transition area between the adhesive stripe and the adhesive-free stripe to have a maximum width of 2 mm in the cross machine direction, - laminating the release liner (310, 410, 610) together with the face stock (101, 201, 501) in such a way that the pressure sensitive adhesive is arranged in between the face stock (101, 201, 501) and the release liner (310, 410, 610) to form a label laminate web, - die-cutting the label laminate web to form a converted label web, wherein the converted label web comprises the release liner (310, 410, 610) with tyre labels (100, 200, 300, 500, 600) attached onto it, wherein o aface (101, 201, 501) of a tyre label has a first section (201a), N the first section comprising an adhesive area (204), N o the face (101, 201, 501) further comprises a second section 3 (201b) contiguous to the first section (201a), the second S 30 section (201b) including an adhesive-free finger tab (203, 503), z o aturn between the first section (201a) and the second section c (2016) is arcuate, n o thefirst section (201a) further comprises at least one adhesive- 3 free area (205) along length of at least one edge of the tyre label (100, 200, 300, 500, 600), and o the adhesive-free finger tab (203, 503) is arranged as an extension of the at least one adhesive-free area (205).

2. The method according to claim 1, wherein the coating thickness profile variation B in cross machine direction of the adhesive stripes is arranged to be no more than +/- 10 %, preferably less than +/- 5 %.

3. The method according to claim 1 or 2, wherein the distance C between the upper and the lower edge of the transition area between the adhesive stripe and the adhesive-free stripe is arranged to have a maximum width of 1 mm in the cross machine direction.

4. The method according to any of the preceding claims, wherein the pressure sensitive adhesive is coated onto the substrate by at least one of the following: a slot die coater, a roll/bar coater or a curtain coater, and the pressure sensitive adhesive is locally removed by a doctor blade in order to form the adhesive-free stripes.

5. The method according to any of the claims 1-3, wherein the pressure sensitive adhesive is coated onto the substrate by a modified slot die nozzle comprising external adhesive flow blocking units in order to form the adhesive-free stripes.

6. The method according to any of the preceding claims, wherein - the first section (201a) of the face (101, 201, 501) is arranged to comprise two adhesive-free areas (205) along lengths of opposite edges of the tyre label (100, 200, 300, 500, 600).

S N 7. The method according to any of the preceding claims, wherein a shape 3 of the first section (201a) of the face is arranged to be one of the following: S 30 a guadrangle, a round, an ellipse, a semicircle. = c 8. The method according to any of the preceding claims, wherein the n pressure sensitive adhesive comprises hot melt pressure sensitive 3 adhesive. & 35

9. The method according to any of the preceding claims, wherein the label laminate web is die-cut in such a way that adjacent and successive tyre labels (100, 200, 300, 500, 600) in the machine direction of the resulting converted label web are uniformly oriented.

10. The method according to any of the preceding claims, wherein the label laminate web is die-cut in such a way that adhesive-free finger tabs (203) of two adjacent tyre labels (100, 200, 300, 500, 600) in cross machine direction are arranged to extend to opposite directions in cross machine direction of the converted label web.

11. The method according to any of the preceding claims, wherein the label laminate web is die-cut in such a way that adjacent longitudinal lines of the tyre labels (100, 200, 300, 500, 600) on the release liner (310, 410, 610) in the machine direction are arranged in an interlocked manner.

12. A tyre label (100, 200, 300, 500, 600) comprising a face (101, 201, 501) and an adhesive layer (102, 402) adjoined to the face (101, 201, 501), wherein - the adhesive layer (102, 402) comprises pressure sensitive adhesive, - the face has a first section (201a), the first section (201a) comprising an adhesive area (204), - the face (101, 201, 501) further comprises a second section (201b) contiguous to the first section (201a), the second section (201b) including an adhesive-free finger tab (203, 503), - a coating thickness profile variation B of the adhesive area (204) is smaller than +/- 15 %, - adistance C between an upper and a lower edge of a transition area N between the adhesive area (204) and the adhesive-free finger tab N (203, 503) has a maximum width of 2 mm, 3 - a turn between the first section (201a) and the second section (201b) N 30 is arcuate, z - the first section (201a) further comprises at least one adhesive-free c area (205) along length of at least one edge of the tyre label (100, n 200, 300, 500, 600), and 3 - the adhesive-free finger tab (203, 503) is arranged as an extension of the at least one adhesive-free area (205).