COMBINED ADHESIVE SYSTEM FOR FLYING SPLICE TAPE AND DOUBLE-SIDED TAPE
20180320028 ยท 2018-11-08
Inventors
Cpc classification
B32B2405/00
PERFORMING OPERATIONS; TRANSPORTING
B65H19/102
PERFORMING OPERATIONS; TRANSPORTING
Y10T428/14
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B65H2301/46078
PERFORMING OPERATIONS; TRANSPORTING
B32B7/12
PERFORMING OPERATIONS; TRANSPORTING
International classification
B32B37/12
PERFORMING OPERATIONS; TRANSPORTING
B65H19/18
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Adhesive tapes and methods for splicing low surface energy substrates with flying splices are provided. An example adhesive tape comprises an adhesive layer and a backing adjacent to the adhesive layer. The adhesive layer comprises a first adhesive comprising a higher shear resistance, cohesive strength, and surface energy relative to a second adhesive, and the second adhesive comprises a higher tack for low surface energy substrates relative to the first adhesive. The second adhesive is different from the first adhesive. The second adhesive is adjacent to the first adhesive and there is substantially no overlap between the first adhesive and second adhesive.
Claims
1. An adhesive tape for providing a flying splice of low surface energy substrates, the adhesive tape comprising: an adhesive layer comprising: a first adhesive comprising a higher shear resistance, cohesive strength, and surface energy relative to a second adhesive, and the second adhesive comprising a higher tack for low surface energy substrates relative to the first adhesive; wherein the second adhesive is different from the first adhesive; wherein the second adhesive is adjacent to the first adhesive; wherein there is substantially no overlap between the first adhesive and second adhesive, and a backing adjacent to the adhesive layer.
2. The adhesive tape of claim 1, further comprising a splitting strip adjacent to the backing and positioned on the opposing side of the backing relative to the adhesive layer.
3. The adhesive tape of claim 1, further comprising a leading edge liner adjacent to and covering at least a portion of the first adhesive.
4. The adhesive tape of claim 1, further comprising a contact side liner adjacent to and covering the second adhesive and at least a portion of the first adhesive.
5. The adhesive tape of claim 1, wherein the adhesive layer is a first adhesive layer; wherein the adhesive tape further comprises a second adhesive layer adjacent to the backing and positioned on the opposing side of the backing relative to the first adhesive layer; wherein the second adhesive layer comprises the first adhesive.
6. The adhesive tape of claim 5, wherein the first adhesive layer comprises the second adhesive in two distinct locations.
7. The adhesive tape of claim 5, wherein the first adhesive layer comprises the second adhesive in one location.
8. The adhesive tape of claim 5, further comprising a release liner covering the first adhesive layer.
9. A method of providing a flying splice on a low surface energy substrate. providing an adhesive tape comprising: an adhesive layer comprising: a first adhesive, and a second adhesive; wherein the second adhesive is different from the first adhesive; wherein the second adhesive is adjacent to the first adhesive; wherein there is substantially no overlap between the first adhesive and second adhesive, and a backing adjacent to the adhesive layer; applying the adhesive layer to a top winding of a first roll of the low surface energy substrate; contacting the applied adhesive layer with an expiring second roll of the low surface energy substrate without stopping or slowing the unwinding of the expiring second roll of the low surface energy substrate.
10. The method of claim 9, wherein the low surface energy substrate is a polyolefin, polyamide, polyethylene terephthalate, polyvinyl chloride, or a combination thereof.
11. The method of claim 9, wherein the first adhesive comprises a higher shear resistance, cohesive strength, and surface energy relative to the second adhesive.
12. The method of claim 9, wherein the second adhesive comprises a higher tack for low surface energy substrates relative to the first adhesive.
13. The method of claim 9, wherein the first adhesive comprises a surface energy greater than the surface energy of the low surface energy substrate.
14. The method of claim 9, wherein the second adhesive comprises a surface energy equal to or less than the surface energy of the low surface energy substrate.
15. The method of claim 9, wherein the first adhesive comprises a bond strength on a low surface energy substrate of at least 8 N/cm or greater and the second adhesive comprises a bond strength on the low surface energy substrate of at least 1 N/cm or greater.
16. A method of rewinding a low surface energy substrate on a core, the method comprising: providing an adhesive tape comprising: an adhesive layer comprising: a first adhesive comprising a higher shear resistance, cohesive strength, and surface energy relative to a second adhesive, and the second adhesive comprising a higher tack for low surface energy substrates relative to the first adhesive; wherein the second adhesive is different from the first adhesive; wherein the second adhesive is adjacent to the first adhesive; wherein there is substantially no overlap between the first adhesive and second adhesive, and a backing adjacent to the adhesive layer; applying the first adhesive of the adhesive layer to the core; wherein the core comprises a non-low surface energy material; contacting the second adhesive of the adhesive layer with the low surface energy substrate.
17. The method of claim 16, wherein the first adhesive comprises a surface energy greater than the surface energy of the low surface energy substrate.
18. The method of claim 16, wherein the second adhesive comprises a surface energy less than the surface energy of the low surface energy substrate.
19. The method of claim 16, wherein the low surface energy substrate is a polyolefin, polyamide, polyethylene terephthalate, polyvinyl chloride, or a combination thereof.
20. The method of claim 16, wherein the first adhesive comprises a bond strength on a low surface energy substrate of at least 8 N/cm or greater and the second adhesive comprises a bond strength on the low surface energy substrate of at least 1 N/cm or greater.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Illustrative examples of the present disclosure are described in detail below with reference to the attached drawing figures, which are incorporated by reference herein, and wherein:
[0014]
[0015]
[0016]
[0017]
[0018]
[0019]
[0020]
[0021]
[0022] The illustrated figures are exemplary only and are not intended to assert or imply any limitation with regard to the environment, architecture, design, or process in which different examples may be implemented.
DETAILED DESCRIPTION
[0023] The present disclosure relates to adhesive tapes used for making flying splices, and more particularly, to single-sided and double-sided adhesive tapes comprising a combined adhesive system to improve adherence on low surface energy substrates in a flying splice operation.
[0024] Unless otherwise indicated, all numbers expressing quantities of components, properties such as molecular weight, reaction conditions, and so forth used in the present specification and associated claims are to be understood as being modified in all instances by the term about. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the examples of the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claim, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. It should be noted that when about is at the beginning of a numerical list, about modifies each number of the numerical list. Further, in some numerical listings of ranges some lower limits listed may be greater than some upper limits listed. One skilled in the art will recognize that the selected subset will require the selection of an upper limit in excess of the selected lower limit.
[0025]
[0026] As illustrated, first adhesive 10 and second adhesive 30 are lined with a leading edge liner 35 and a contact side liner 40. Leading edge liner 35 extends from first lateral edge 15 to position 45, which is proximate first lateral edge 15. Contact side liner 40 extends from second lateral edge 25 to position 45.
[0027] A backing 50 (obscured in
[0028] On the side of the backing 50 opposite the first adhesive 10 and the second adhesive 30, a splitting strip 55 (obscured in
[0029]
[0030] The second from the top winding 80 of the new roll of material 70 is affixed to the splitting strip 55 of adhesive tape 5 by substrate adhesive layer 65. As such, premature unwinding of the leading edge 75 of the top winding from the new roll of material 70 may be prevented when the new roll of material 70 is accelerated. With adhesive tape 5 adhered to both the leading edge 75 and the second from the top winding 80 of the new roll of material 70, the new roll of material 70 may be brought to contact with the moving expiring roll of material (as illustrated below). When said contact is desired, the contact side liner 40 may be removed prior, exposing second adhesive 30 and the remaining portion of first adhesive 10.
[0031]
[0032] Without limitation by theory, the second adhesive 30, possessing increased tack for the substrate of the expiring roll of material 85, allows the flying splice to be made when contact times between the new roll of material 70 and the expiring roll of material 85 are short. The second adhesive 30 thus allows for the flying splice to be started and for the leading edge 75 to be pulled from the new roll of material 70. The first adhesive 10, possessing high shear and cohesive strength, allows the flying splice to be maintained when the flying splice is pulled through a material processor and subjected to dynamic tensions and high temperatures.
[0033]
[0034] As discussed above regarding the embodiment illustrated in
[0035] Second adhesive 30 possesses a higher tack for low surface energy substrates relative to first adhesive 10. Second adhesive 30 should possess a tack sufficient to adhere a new roll of a low surface energy material to an expiring roll of a low surface energy material in a flying splice operation with a short contact time between the second adhesive 30 and the low surface energy material. First adhesive 10 may possess a higher surface energy relative to second adhesive 30. As such, second adhesive 30 may be a softer adhesive than first adhesive 10.
[0036] As illustrated, the first adhesive 10 and second adhesive 30 of the first adhesive layer 106 are lined with a release liner 120 which covers all of first adhesive 10 and second adhesive 30 and may be removed to expose first adhesive 10 and second adhesive 30 of the first adhesive layer 106 when a flying splice is to be provided.
[0037]
[0038]
[0039] As discussed above regarding the embodiment presented in
[0040] Additionally, the first adhesive 10 and the second adhesive 30 are sufficient for other operations that may utilize low surface energy materials. For example, the adhesive tape 105 may be used in a core starting operation wherein the tape is applied to a core and a material such as a low surface energy material is rapidly wound around the core. In an example core starting operation, which may take proceed after processing of the low surface energy substrate (e.g., printing, coating, slitting etc.) in the flying splice operation described above, the processed low surface energy substrate may be rewound on a core in the end of the processing machine. In continuous processes (i.e., not-stopping operations), automatic rewinders can be used. In these systems, adhesive tape 5 and/or adhesive tape 105 as described above in
[0041] With reference to
[0042] A bond strength test (Test A) was performed to determine the desired minimum bond strength of the first adhesive 10 and the second adhesive 30 on a specific example of a low surface energy substrate. A determination of the bond strength on polyethylene panel film was carried out. The sample adhesive tape for investigation comprised a standard polyethylene terephthalate carrier or paper backing having a thickness of 25 m (PET) or 65 m (paper), coated on one side with the first adhesive 10 or the second adhesive 30. A strip of the sample adhesive tape 10 to 28 mm wide was pressed under load (2 kg) onto the fixed polyethylene panel film. Immediately thereafter, the sample adhesive tape was peeled from the polyethylene panel film at an angle of 180 and a speed of 300 mm/min, and the force required to accomplish this at 23 C. temperature was measured.
[0043] A rolling ball tack test (Test B) was performed to determine the minimum tack of the first adhesive 10 and the second adhesive 30 on a specific example of a substrate with a low contact time. The determination of the tack of the first adhesive 10 and the second adhesive 30 on a steel ball was carried out as follows: adhesive tape samples (i.e., a specific embodiment of first adhesive 10 or the second adhesive 30) were rolled over at least 5 times with a 5.7 g stainless steel ball having a diameter of 7/16 inches (11.112 mm). The balls are cleaned accordingly before use (e.g., with heptane and acetone). The adhesive samples are fixed onto a base plate. The steel balls are rolled down a ramp with an incline of 30 and a rolling length of 6.5 inches. The ramp is placed flat on the adhesive samples, such that the ball exist the ramp directly on to the adhesive samples. The maximum rolling distance is then calculated from an average of the samples. The determination was made under test conditions of 231 C. and 505% relative humidity.
[0044] A microshear travel test (Test C) was performed to determine the minimum shear strength of bonded samples of the first adhesive 10 with a specific example of a low surface energy substrate. The determination of the shear strength of the first adhesive 10 under a temperature load of 40 C. was carried out as follows: adhesive tape samples (i.e., a specific embodiment of first adhesive 10) were adhered to a stainless steel plate, and then rolled over 3 times with a 2 kg steel roller at a speed of 12 m/min. The sample was then loaded at one end with a weight of 100 g. The test plate was then heated to the desired temperature load of 40 C. A measurement was made of the slip travel of the sample over a period of 15 minutes. After these first 15 minutes the weight was removed, and the relaxation was measured for a period of a further 15 minutes. The elastic component was computed (in %), which represents a measure of the network density. The testing was performed at a room temperature of 23 C. and a relative humidity 50%. The average measurement value was 35 m, with the maximum being 55 m.
[0045] Based on the above testing, embodiments of the first adhesive 10 possess a bond strength (Test A) on the low surface energy substrates described herein of at least 8 N/cm or greater. Embodiments of the first adhesive 10 possess a rolling ball distance (Test B) on the substrates described herein 25 mm or less. Embodiments of the first adhesive 10 possess a cohesion corresponding to a microshear travel test (Test C) on the low surface energy substrates described herein of less than 55 m. In some embodiments, the first adhesive 10 may possess a surface energy greater than that of the low surface energy substrates described herein. In some embodiments, the first adhesive 10 may possess a surface energy greater than that of the second adhesive 30 described herein.
[0046] Based on the above testing, embodiments of the second adhesive 30 possess a bond strength (Test A) on the low surface energy substrates described herein of at least 1 N/cm or greater. Embodiments of the second adhesive 30 possess a rolling ball distance (Test B) on the substrates described herein 20 mm or less. In some embodiments, the second adhesive 30 may possess a surface energy lower than that of the low surface energy substrates described herein. In some embodiments, the second adhesive 30 may possess a surface energy less than that of the first adhesive 10 described herein.
[0047] The embodiments described herein may be of particular benefit in applications using low surface energy substrates. Low surface energy substrates as described herein, are any materials having a surface energy between 20-40 mN/m (dyn/cm). Examples of low surface energy substrates may include polyolefins, for example, polyethylene, polypropylene, and the like. Any variety of polyethylene (hereafter PE) may be a low surface energy substrate as described herein, including, but not limited to, low-density, linear low-density, medium-density, high-density, chemically modified PE, and the like. Any variety of polypropylene (hereafter PP) may be a low surface energy substrate as described herein, including, but not limited to, biaxially oriented, mono oriented, cast, pearled, and the like. Additional examples of low surface energy substrates may include polypropylene terephthalate (hereafter PET), polyamides, polyvinyl chloride (hereafter PVC), or combinations thereof.
[0048] One or more illustrative examples incorporating the embodiments disclosed herein are presented. Not all features of a physical implementation are described or shown in this application for the sake of clarity. Therefore, the disclosed systems and methods are well adapted to attain the ends and advantages mentioned, as well as those that are inherent therein. The particular examples disclosed above are illustrative only, as the teachings of the present disclosure may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown other than as described in the claims below. It is therefore evident that the particular illustrative examples disclosed above may be altered, combined, or modified, and all such variations are considered within the scope of the present disclosure. The systems and methods illustratively disclosed herein may suitably be practiced in the absence of any element that is not specifically disclosed herein and/or any optional element disclosed herein.
[0049] Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the spirit and scope of the disclosure as defined by the following claims.