Methods and Apparatus for Applying Adhesives in Patterns to an Advancing Substrate
20180221911 ยท 2018-08-09
Inventors
Cpc classification
B05C5/027
PERFORMING OPERATIONS; TRANSPORTING
B05B12/16
PERFORMING OPERATIONS; TRANSPORTING
B05C5/025
PERFORMING OPERATIONS; TRANSPORTING
B05C5/0245
PERFORMING OPERATIONS; TRANSPORTING
D21H23/46
TEXTILES; PAPER
B05C5/0254
PERFORMING OPERATIONS; TRANSPORTING
B05C5/0279
PERFORMING OPERATIONS; TRANSPORTING
International classification
B05C5/02
PERFORMING OPERATIONS; TRANSPORTING
A61F13/15
HUMAN NECESSITIES
B05D1/26
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Methods and apparatuses herein provide for the application of viscous fluids, such as adhesives, in pre-determined patterns, to an advancing substrate. The fluid applicator comprises a slot die applicator and a substrate carrier. The slot die applicator comprises a plurality of applicator channels, each applicator channel being controlled by a switching valve, and wherein the switching valves are independently switchable.
Claims
1. An apparatus for applying adhesive in a pattern to an advancing substrate, the apparatus comprising: a slot die applicator including a slot opening defined by a first lip and a second lip; a substrate carrier adapted to advance the substrate past the slot die applicator, wherein when a first surface of the substrate is disposed on the substrate carrier, the substrate carrier is adapted to advance a second, opposing, surface of the substrate past the slot opening of the slot die applicator, the substrate carrier comprising: a base surface; and a pattern element, wherein the pattern element includes a pattern surface, and wherein the pattern element protrudes outward from the base surface to define a distance, Hp, between the pattern surface and the base surface; wherein as the substrate carrier advances the second surface of the substrate past the slot opening, the pattern element is advanced such that the pattern surface repeatedly advances past the first lip, the slot opening, and the second lip of the slot die applicator; and wherein the slot die applicator comprises a plurality of applicator channels, each applicator channel being controlled by a switching valve, and wherein the switching valves are independently switchable.
2. The apparatus according to claim 1, wherein the distance of the channel between each of the switching valves and each of the corresponding slot openings is substantially equal.
3. The apparatus according to claim 1, wherein the number of adjacent application channels is at least four, and wherein the width, Dn, of each of the supply nozzles of each of the adjacent channels is from about 1 mm to about 10 mm.
4. The apparatus according to claim 3, wherein the width, Dn, of each of the supply nozzles of each of the adjacent channels is from about 2 mm to about 5 mm.
5. The apparatus according to claim 3, wherein the distance, Dg, between each supply nozzle of each of the adjacent application channels is less than about 1 mm.
6. The apparatus according to claim 1, wherein the substrate carrier is positioned adjacent the slot die applicator to define a minimum distance, Hg, between the pattern surface of the pattern element and the first lip and the second lip that is less than the unconstrained caliper, Hs, of the substrate; and wherein a sum of the distance, Hp, and distance, Hg, is greater than the unconstrained caliper, Hs, of the substrate.
7. A method for applying adhesive discharged from a slot die applicator to a substrate in a pattern, the slot die applicator comprising a plurality of applicator channels, the method comprising the steps of: continuously advancing the substrate in a machine direction; engaging the substrate with a substrate carrier, the substrate carrier comprising: a pattern element, wherein the pattern element includes a pattern surface; positioning the substrate carrier adjacent the slot die applicator to define a minimum distance, Hg, between the pattern surface of the pattern element and the first lip and the second lip that is less than the unconstrained caliper, Hs, of the substrate; advancing the second surface of the substrate past the slot die applicator while the first surface of the substrate is disposed on the substrate carrier; intermittently compressing the substrate between the slot die applicator and the pattern surface of the pattern element by advancing the pattern element such that the pattern surface of the pattern element advances past the first lip, the slot opening, and the second lip of the slot die applicator while the first surface of the substrate is disposed on the substrate carrier; and wherein the flow of adhesive supplied to each of the applicator channels is independently controlled by a switching valve, and wherein each of the switching valves are independently switchable.
8. The method according to claim 7, wherein the distance of the channel between each of the switching valves and each of the corresponding slot openings is substantially equal.
9. The method according to claim 7, wherein the number of adjacent application channels is at least four, and wherein the width, Dn, of each of the supply nozzles of each of the adjacent channels is from about 1 mm to about 10 mm.
10. The method according to claim 9, wherein the width, Dn, of each of the supply nozzles of each of the adjacent channels is from about 2 mm to about 5 mm.
11. The method according to claim 9, wherein the distance, Dg, between each supply nozzle of each of the adjacent application channels is less than about 1 mm.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE INVENTION
[0023] The following term explanations may be useful in understanding the present disclosure:
[0024] Absorbent article is used herein to refer to consumer products whose primary function is to absorb and retain soils and wastes. Non-limiting examples of absorbent articles include diapers, training pants, pull-on pant-type diapers, refastenable diapers or pant-type diapers, incontinence briefs and undergarments, diaper holders and liners, feminine hygiene garments such as panty liners, absorbent inserts, and the like.
[0025] Diaper is used herein to refer to an absorbent article generally worn by infants and incontinent persons about the lower torso.
[0026] The term disposable is used herein to describe absorbent articles which generally are not intended to be laundered or otherwise restored or reused as an absorbent article (e.g., they are intended to be discarded after a single use and may also be configured to be recycled, composted or otherwise disposed of in an environmentally compatible manner).
[0027] As used herein, the term unconstrained caliper refers to the caliper of the substrate measured according to Edana WSP 120.1 (05), with a circular presser foot having a diameter of 25.400.02 mm and an applied force of 2.1 N (i.e. a pressure of 4.140.21 kPa is applied).
[0028] Aspects of the present disclosure involve methods and apparatuses utilizing continuous substrates for manufacturing articles, and more particularly, methods and apparatuses for applying fluids onto an advancing substrate. Particular embodiments of the apparatuses and methods disclosed herein provide for the application of viscous fluids, such as adhesives, and in some embodiments, the application of adhesives in pre-determined patterns to an advancing substrate. Embodiments of a fluid application apparatus are discussed in more detail below in the context of applying adhesives to an advancing substrate having an unconstrained caliper, Hs, and having a first surface disposed opposite of a second surface. The fluid application apparatus may include a slot die applicator and a substrate carrier. The slot die applicator may include a slot opening, a first lip, and a second lip, the slot opening located between the first lip and the second lip. And the substrate carrier may be adapted to advance the substrate past the slot die applicator as the slot die applicator discharges adhesive onto the substrate. In operation, when the first surface of the substrate is disposed on the substrate carrier, the substrate carrier advances the second surface of the substrate past the slot opening of the slot die applicator. It is to be appreciated that the apparatus and processes disclosed herein may be used to apply various types of fluids and adhesives in various different patterns to an advancing substrate other than those described and depicted herein.
[0029] As discussed in more detail below, the substrate carrier may include a base surface and a pattern element. In some embodiments, the substrate carrier may include a plurality of holes therein, and as such, do not include base surfaces. The pattern element includes a pattern surface and protrudes outward from the base surface. As such, in substrate carriers configured with a base surface, the pattern surface and the base surface are separated by a distance, Hp. In addition, the substrate carrier is positioned adjacent the slot die applicator to define a minimum distance, Hg, between the pattern surface of the pattern element and the first lip and the second lip that is less than the unconstrained caliper, Hs, of the substrate, wherein a sum of the distance, Hp, and distance, Hg, is greater than the unconstrained caliper, Hs, of the substrate. Thus, as the substrate carrier advances the second surface of the substrate past the slot opening, the pattern element is advanced such that the pattern surface repeatedly advances past the first lip, the slot opening, and the second lip of the slot die applicator. In turn, the substrate is intermittently compressed between the slot die applicator and the pattern surface of the pattern element as the pattern element advances past the first lip, the slot opening, and the second lip of the slot die applicator. As the substrate is intermittently compressed, adhesive discharged from the slot die applicator is applied onto the second surface of the advancing substrate. More particularly, the adhesive is applied to the substrate in an area having a shape that is substantially the same as a shape defined by the pattern surface.
[0030] The apparatuses and methods disclosed herein may include substrate carriers having various configurations. For example, in some embodiments the substrate carrier may be configured as a roller. In other embodiments, the substrate carrier may include an endless belt. The substrate carriers may also utilize various outer surface arrangements. For example, the base surface may be configured as a continuous surface and the substrate carrier may include a plurality of discrete pattern elements separated from each other by the continuous surface. In such a configuration, each pattern element may include a pattern surface and each pattern element may protrude outward from the continuous surface such that each pattern surface is separated from the continuous surface by the distance, Hp. In another example, the pattern surface may be configured as a continuous surface and the base surface may include a plurality of discrete base surfaces separated from each other by the pattern element. In such a configuration, the pattern element may protrude outward from each of the base surfaces such that each base surface is separated from the continuous surface by the distance, Hp. As previously mentioned, in some configurations, the substrate carrier may be configured without base surfaces, such as for example, a belt configured with holes extending through the belt. As such, the holes may be separated from each other by a continuous pattern element. It is to be appreciated that the pattern surface of the pattern element may be configured in various different shapes and sizes and may be configured to define various different patterns. As such, adhesive may be transferred from the slot die applicator to define various patterns on a substrate.
[0031] As mentioned above, apparatuses and methods of the present disclosure may be utilized to apply adhesives to continuous substrates used in the manufacture of absorbent articles. Such substrates may be utilized in absorbent article components such as, for example: backsheets, topsheets, absorbent cores, front and/or back ears, fastener components, and various types of elastic webs and components such as leg elastics, barrier leg cuff elastics, and waist elastics. Exemplary descriptions of absorbent article components and substrates are provided below with reference to
[0032] Although much of the present disclosure is provided in the context of manufacturing absorbent articles, it is to be appreciated that the apparatuses and methods disclosed herein may be applied to the manufacture of other types of articles and products manufactured from continuous substrates. Examples of other products include absorbent articles for inanimate surfaces such as consumer products whose primary function is to absorb and retain soils and wastes that may be solid or liquid and which are removed from inanimate surfaces such as floors, objects, furniture and the like. Non-limiting examples of absorbent articles for inanimate surfaces include dusting sheets, pre-moistened wipes or pads, pre-moistened cloths, paper towels, dryer sheets and dry-cleaning clothes such. Additional examples of products include absorbent articles for animate surfaces whose primary function is to absorb and contain body exudates and, more specifically, devices which are placed against or in proximity to the body of the user to absorb and contain the various exudates discharged from the body. Non-limiting examples of incontinent absorbent articles include diapers, training and pull-on pants, adult incontinence briefs and undergarments, feminine hygiene garments such as panty liners, absorbent inserts, and the like, toilet paper, tissue paper, facial wipes or clothes, and toilet training wipes.
[0033]
[0034] It is to be appreciated that the slot die applicator 102 shown in
[0035] Various types of substrate carriers 104 may be used in accordance with the apparatuses and methods herein. For example,
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[0037] Within each bank of applicator nozzles, the width of the nozzle is Dn and the gap between adjacent nozzles is Dg. Preferably nozzle width, Dn, is from 1 mm to 10 mm, more preferably from 2 mm to 5 mm. Preferably the gap, Dg, between adjacent nozzles is less than 1 mm.
[0038] As previously mentioned, the methods and apparatuses herein include a substrate carrier adapted to advance a substrate past a slot die applicator.
[0039] With continued reference to
[0040] The following provides a more detailed description of fluid transfer from the slot die applicator to the substrate with reference to
[0041]
[0042] As shown in
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[0046] As previously mentioned, various forms and configurations of substrate carriers may be used with the presently disclosed methods and apparatuses.
[0047] As previously mentioned, the apparatuses 100 and methods herein may be used to provide for the application of adhesives in patterns to substrates and components during the manufacture of various different products. For the purposes of a specific illustration,
[0048] As shown in
[0049] The absorbent article may also include an elastic waist feature 202 shown in
[0050] As shown in
[0051] The diaper 252 may be provided in the form of a pant-type diaper or may alternatively be provided with a re-closable fastening system, which may include fastener elements in various locations to help secure the diaper in position on the wearer. For example, fastener elements may be located on the first and second ears and may be adapted to releasably connect with one or more corresponding fastening elements located in the second waist region. It is to be appreciated that various types of fastening elements may be used with the diaper.
[0052] In the context of the previous discussion, the apparatuses 100 and methods herein may be used to provide for the application adhesives in patterns to substrates and components during the manufacture of an absorbent article. For example, adhesives may be applied in various patterns to portions of any of the topsheet, backsheet, absorbent core, leg cuffs, waist feature, ears, and fastening elements during the manufacture of an absorbent article. In some instances, the adhesive may be a different color than that of the substrate.
[0053] According to one aspect the present invention relates to a method, for applying adhesive discharged from a slot die applicator 102 to a substrate 106 in a pattern, the slot die applicator 102 comprising a plurality of applicator channels 162, the method comprising the steps of: continuously advancing the substrate 106 in a machine direction; [0054] engaging the substrate 106 with a substrate carrier, the substrate carrier 104 comprising: a pattern element 122, wherein the pattern element 122 includes a pattern surface; [0055] positioning the substrate carrier 104 adjacent the slot die applicator 102 to define a minimum distance, Hg, between the pattern surface 126 of the pattern element 122 and the first lip 116 and the second lip 118 that is less than the unconstrained caliper, Hs, of the substrate 106; [0056] advancing the second surface 110 of the substrate past the slot die applicator 102 while the first surface of the substrate is disposed on the substrate carrier 104; [0057] intermittently compressing the substrate 106 between the slot die applicator 102 and the pattern surface 126 of the pattern element 122 by advancing the pattern element 122 such that the pattern surface 126 of the pattern element 122 advances past the first lip 116, the slot opening, and the second lip 118 of the slot die applicator 102 while the first surface of the substrate is disposed on the substrate carrier 104;
[0058] wherein the flow of adhesive supplied to each of the applicator channels 162 is independently controlled by a switching valve 166, and wherein each of the switching valves 166 are independently switchable.
[0059] This application claims the benefit of European Patent Application No. EP17155095.7 filed on Feb. 8, 2017, the entirety of which is incorporated by reference herein.
[0060] The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as 40 mm is intended to mean about 40 mm.
[0061] Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
[0062] While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.