WO2022197475A2

WO2022197475A2 - Adjustable linear substrate infusion

Info

Publication number: WO2022197475A2
Application number: PCT/US2022/019121
Authority: WO
Inventors: Nathan Anderson
Original assignee: Anderson Group, Ltd
Priority date: 2021-03-16
Filing date: 2022-03-07
Publication date: 2022-09-22
Also published as: WO2022197475A3

Abstract

A method of forming an active agent infused linear material comprises flowing a liquid infusion solution comprising one or more active molecules into an infusion tank such that the liquid infusion solution fills the infusion tank to a fluid level, conveying a linear substrate in a first direction using a one or more linear substrate guides such that the linear substrate extends over the liquid infusion solution, and moving at least one of the one or more linear substrate guides in a second direction into the liquid infusion solution such that the linear substrate is immersed in the liquid infusion solution while the liquid infusion solution is at an infusion temperature to infuse the one or more active molecules into or onto a surface of the linear substrate thereby forming an active agent infused linear material.

Description

ADJUSTABLE LINEAR SUBSTRATE INFUSION

Cross-Reference to Related Application

[0001] This application claims priority to U.S. Provisional Application No. 63/161,537 filed March 16, 2021, for “Adjustable Linear Substrate Infusion”, the entire disclosure of which is hereby incorporated by reference.

Field

[0002] The present specification generally relates to imparting desirable characteristics to linear substrates such as polymeric substrates. The specification provides improved devices and methods for adding active agents that impart such characteristics to a linear substrate.

Technical Background

[0003] The inclusion of desirable characteristics to polymeric substrates has historically required a physical association of chemical materials to the substrate during the manufacturing process itself. For example, imparting color to a polymer is historically done by intermixing or compounding pigment or dye particles into a melted polymer either before polymerization or before forming into the final desired shape so that the dye particles can penetrate throughout the material and impart color to the final product.

[0004] Such methods have several drawbacks such as the dye particle is subjected to one or more melt/cool cycles during the manufacture of the final article which could result in degradation of the dye and alterations of color relative to that desired. A first heat step is present when the dye is incorporated into the melted polymeric material itself, and a second occurs when the article is formed into the final article shape such as by extrusion or other thermoforming.

[0005] Other prior methods of imparting desirable physical or chemical characteristics to polymeric substrates such as color or weathering rely on coating of the final article such as by painting color or other materials onto the surface of the article. Such configurations are subject to degradation such as by cracking, peeling, chipping or other that removes all or a portion of the coated material and reveals weaknesses on the overall article. Further, coatings must have sufficient flexibility to maintain integrity on a flexible substrate and such flexibility is difficult to achieve.

[0006] As such, there is a desire to develop new methods and systems for imparting desirable physical or chemical characteristics to polymeric substrates such as linear polymeric substrates.

SUMMARY

[0007] The following summary is provided to facilitate an understanding of some of the innovative features unique to the present disclosure and is not intended to be a full description. A full appreciation of the various aspects of the disclosure can be gained by taking the entire specification, claims, drawings, and abstract as a whole.

[0008] Provided are new methods and systems that address the need for imparting desirable characteristics to a linear substrate either preformed or as a final or near final step of a formation process. The systems provide for rapid and robust addition of molecules that can provide color, ability to withstand weathering, or other desirable characteristic to a linear substrate. The systems and methods can be practiced on the fly with very rapid infusion of active agents to the linear substrate providing increased throughput and rapid manufacturing of linear substrates which can be tailored and adjusted on demand.

[0009] It is a first object of the disclosure to provide a method of forming an active agent infused linear material that comprises flowing a liquid infusion solution comprising one or more active molecules into an infusion tank such that the liquid infusion solution fills the infusion tank to a fluid level, conveying a linear substrate in a first direction using a one or more linear substrate guides such that the linear substrate extends over the liquid infusion solution, and moving at least one of the one or more linear substrate guides in a second direction into the liquid infusion solution such that the linear substrate is immersed in the liquid infusion solution while the liquid infusion solution is at an infusion temperature to infuse the one or more active molecules into or onto a surface of the linear substrate thereby forming an active agent infused linear material.

[0010] It is another object of the disclosure to provide a method of forming an active agent infused linear material that comprises manipulating a first one or more linear substrate support guides to immerse a linear substrate into a first infusion tank containing a first liquid infusion solution heated to a first infusion temperature to infuse a first set of active molecules into or onto a surface of the linear substrate, conveying the linear substrate along a feed direction over a second infusion tank; and manipulating a second one or more linear substrate support guides to immerse the linear substrate into a second liquid infusion solution in the second infusion tank heated to a second infusion temperature to infuse a second set of active molecules into or onto the surface of the linear substrate.

[0011] It is another object of the present disclosure to provide a linear substrate infusion system comprising a first infusion tank comprising an open end for receiving a linear substrate and an immersion unit disposed in alignment with the open end. The immersion unit includes a one or more movable linear substrate guides that are attached to the immersion unit via a one or more linear substrate guide supports such that the one or more movable linear substrate guides are independently movable towards the open end to be selectively inserted into the first infusion tank and removed from the first infusion tank.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0012] The aspects set forth in the drawings are illustrative and exemplary in nature and not intended to limit the subject matter defined by the description and claims. The following detailed description of the illustrative aspects can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

[0013] FIG. 1 A schematically depicts a linear substrate infusion system configured for infusion of a first colored dye, according to one or more aspects described herein;

[0014] FIG. IB schematically depicts a linear substrate infusion system configured for change over from a first colored dye to a second colored dye, according to one or more aspects described herein;

[0015] FIG. 1 C schematically depicts a linear substrate infusion system configured for infusion of a second colored dye, according to one or more aspects described herein;

[0016] FIG. 2A schematically depicts an infusion tank and an immersion unit of the linear substrate infusion system of FIG. 1A, with the immersion unit being in a starting position, according to one or more embodiments described herein; [0017] FIG. 2B schematically depicts the infusion tank and immersion unit of FIG. 2A, with the immersion unit being in first immersion position, according to one or more embodiments described herein;

[0018] FIG. 2C schematically depicts the infusion tank and immersion unit of FIG. 2A, with the immersion unit being in second immersion position, according to one or more embodiments described herein;

[0019] FIG. 2D schematically depicts a cross-sectional view of a linear substrate guide of the immersion unit of FIG. 2 A through the line 2D-2D depicted in FIG. 2C, according to one or more embodiments described herein; and

[0020] FIG. 3 schematically depicts an infusion tank system including multiple immersion systems with multiple infusion tanks being disposed in series, according to one or more embodiments described herein.

DETAILED DESCRIPTION

[0021] As described herein, various aspects of linear substrate infusion systems are disclosed with features or structures that promote infusion of an active agent into the substrate or a coating or layer on the substrate. The methods and systems are optionally used with preformed substrates that are subjected to the methods with the substrate at ambient temperature. The systems provided are useful for infusion of color or anti-weathering agent(s), as two examples, into polymeric materials made from or otherwise including thermoset plastics or thermoplastics. The processes and systems disclosed herein are particularly suitable for imparting desired characteristics to linear polymeric substrates.

[0022] In the following description of the various examples and components of this disclosure, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various example structures and environments in which aspects of the disclosure may be practiced. It is to be understood that other structures and environments may be utilized and that structural and functional modifications may be made from the specifically described structures and methods without departing from the scope of the present disclosure. [0023] It will be understood that when an element is referred to as being “on” another element, it can be directly on the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present.

[0024] It will be understood that, although the terms “first,” “second,” “third” etc. may be used herein to describe various elements, components, regions, layers, and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, “a first element,” “component,” “region,” “layer,” or “section” discussed below could be termed a second (or other) element, component, region, layer, or section without departing from the teachings herein.

[0025] The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms, including “at least one,” unless the content clearly indicates otherwise. “Or” means “and/or.” As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof. The term “or a combination thereof’ means a combination including at least one of the foregoing elements.

[0026] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure or relevant portion thereof belongs. It will be further understood that terms such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0027] The description is primarily directed to the infusion of one or more active molecules such as colored dye(s) or others into a polymeric material forming or as a part of a linear substrate. Any linear substrate is suitable for use such as hollow, solid, or multilayer linear substrates. Such is presented for illustrative and descriptive purposes alone. The disclosure is equally applicable to any linear substrate that includes a polymeric surface material, sometimes referred to herein as “linear polymeric substrates,” such as but not limited to a hose or other hollow tubing, solid linear substrates, multicomponent or multilayer linear substrates, sheeting or films of an elongated nature, among other items recognized in the art. A linear substrate may be continuous for a length that is optionally of 10 feet or longer, optionally of 100 feet or longer, optionally of 1000 feet or longer, optionally of 10,000 feet or longer. The processes and systems provided herein may be used to infuse an active material into a linear substrate that is not limited by length. A continuous linear substrate optionally has a length that is greater than 1000 times or more the maximal cross sectional dimension of the linear substrate. The diameter or other maximal cross section linear dimension of a linear substrate optionally does not exceed 10 cm, optionally 2 cm, optionally 1 cm, optionally 0.5 cm, optionally 0.1 cm, optionally 0.01 cm. The diameter or maximal cross sectional linear dimension (excluding length) of a linear substrate or polymeric material layer thereon is optionally greater than 50 pm, optionally greater than 500 pm, optionally greater than 0.1 cm, optionally greater than 0.2 cm, optionally greater than 1 cm. Accordingly, the diameter or other maximal cross section linear dimension of a linear substrate may be optionally from 500 pm to 10 cm, optionally from 0.1 cm to 2 cm, optionally from 0.2 cm to 1 cm, or optionally within any range within the values recited herein. The present disclosure is applicable to linear substrates having a plurality of different shapes (e.g., wires, films, or sheets).

[0028] While much of the specification is directed to imparting color into a linear polymeric substrate, it is appreciated that molecules other than dyes are equally able to be effectively infused into the surface of the linear polymeric substrate to impart other desired characteristic(s) such as but not limited to anti-weathering illustratively but not limited to imparting UV or other light protection, anti-static, lubricity, among others. As such, a “dye” as used herein is equally represented by other molecules that impart one or more other desirable physical or chemical characteristics to the final product and may or may not impart a color or color change to the final product.

[0029] In one example, a process for infusing a linear polymeric substrate is provided. A process can include infusing a linear polymeric substrate that can be used for any of a number of purposes such as for conducting, transmitting, or transporting a fluid, electrical energy, light energy, or other. A process employs a solvent system for infusing one or more desired active molecules into the surface of a polymer to thereby create an infused surface that has the desired characteristic such as color or other. In one specific example, the infused material could be a dye or other pigment. In one example, the linear polymeric substrate can be a hose with a typical uncolored outer surface. The hose may have one or multiple polymer coatings consisting of one or multiple polymers. In one example, the hose can be white, gray or other background color as is produced or desired to be produced prior to infusion with the desired active.

[0030] In some aspects, the infusion of one or more actives can be achieved either directly after formation of a final shape of a linear substrate, optionally immediately off an extruder, or can be employed on previously manufactured source substrate material. For example, after the formation of a polymer in the desired linear configuration (e.g. hollow, solid, coating a core, such as in the case of a wire, or other), the linear substrate could be immediately infused using the processes and systems discussed herein or previously manufactured substrate could be infused using the processes and systems discussed herein. In particular aspects, color is infused into pre manufactured substrate, optionally on an as-needed basis. In other aspects, color is infused into material within moments (e.g., less than 1 minute) following extrusion.

[0031] A linear substrate optionally includes an outer layer that includes one or more polymeric materials suitable to be infused with an active agent, optionally a dye or other pigment. Exemplary polymeric materials include thermoplastics or thermoset plastics. More specific illustrative examples of a polymeric material include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polycarbonates (PC), polyethylene (PE), cross-linked polyethylene (PEX), polylactic acid (PLA), PET copolymers, acrylics, polyethylene naphthalate (PEN), polyamides, polycarbonate co-polymers, polyvinyl chloride (PVC), elastomeric polymers, urethanes, acrylic co-polymers (including but not limited to ethylene (meth)acrylic acid co-polymers, such as those commercially available under the tradename Surlyn™ from DuPont), acrylonitrile butadiene styrene (ABS), or other plastics. In particular aspects, the polymeric material is a polyamide or polycarbonate. In some particular aspects, the polymeric material is or includes a polyamide.

[0032] Processes of coloring a linear substrate having at least an outer layer of one or more polymeric materials, optionally a thermoplastic, includes forming a dye infused linear polymeric substrate optionally by: providing a polymeric material in the form of a linear substrate; mixing, immersing, coating or otherwise contacting the polymeric material with an infusion agent solution at an infusion temperature optionally below the melting temperature of the polymeric material and for an infusion time, the infusion agent solution including one or more dye and/or other active materials and, optionally, one or more infusion agents, the one or more dye and/or other active materials optionally imparting a color change to the polymer relative to a like polymeric material that is not infused with the one or more active materials, the one or more infusion agents operable to promote penetration of the active material into the surface of the polymeric material; and infusing the active material into the polymer material by said mixing, immersing, or coating step thereby forming a dye infused linear polymeric substrate.

[0033] An infusion temperature is optionally below the glass transition temperature (Tg) of the polymeric material of the linear substrate, optionally below the melting temperature of the polymeric material. In some aspects, the infusion temperature is above the Tg. Optionally, the infusion temperature is at or above the Tg and below the melting temperature. In some aspects, an infusion temperature is from 50 degrees Celsius to 98 degrees Celsius, optionally 81 degrees Celsius to 91 degrees Celsius. In some aspects, an infusion temperature is from 60 degrees Celsius to 99.9 degrees Celsius, optionally 90 degrees Celsius to 99 degrees Celsius. Optionally, an infusion temperature does not exceed 100 degrees Celsius. Optionally, an infusion temperature does not exceed 99 degrees Celsius.

[0034] A linear substrate is infused for an infusion time. An infusion time is optionally 1 minute or less, optionally at or between 0.01 second to 1 minute. A polymer used in the processes optionally is or includes: a polyamide such as nylon; a polyester, optionally polyethylene, optionally polyethylene terephthalate; polyvinylchloride; or polycarbonate. The active material following infusion optionally penetrates the polymer to a depth of less than 2 millimeters, optionally to less than 1 millimeter. In some aspects, an active material is infused to a final depth of less than 200 microns. In any of the aspects, an active material is optionally a dye such as optionally an azo or quinone dye, or combinations thereof. In some aspects, the polymer is preheated to the infusion temperature prior to contact with an infusion solution and/or dye material. Optionally, the infusion solution and/or dye material is heated to the infusion temperature and an unheated polymer is immersed, mixed, or otherwise contacted with the infusion solution. [0035] In some aspects, a polymeric material is contacted with an infusion solution including one or more infusion agents. An infusion agent is a chemical composition operable to promote penetration of a barrier material into the surface of a polymeric material. An infusion solution is optionally an aqueous solution, or a solution of one or more organic solvents or solutes. An infusion solution is optionally entirely formed of an infusion agent and an active material. In some aspects, an infusion solution includes water, an infusion agent, and optionally one or more additives. In some aspects, the infusion solution includes water. In some aspects, the water is tap water. An additive is illustratively one more surfactants or emulsifiers, as will be discussed in greater detail below. An infusion solution optionally includes one or more dyes or other active material. For example, in some aspects, the infusion solution consists essentially of a dye and water. As another example, in some aspects, the infusion solution consists essentially of a dye, water, and acetic acid solvent. As yet another example, in some aspects, the infusion solution consists essentially of a dye, water, and a glycol. In any of these aspects, the water may be tap water. In some aspects, the infusion solution is a liquid infusion solution.

[0036] In some aspects, an active material is suitable to impart color or a change in color to the linear substrate. In some aspects, the active material is a dye. The dye used to form a colored linear polymer according to particular aspects is optionally a stable dye or an unstable dye. In some aspects, a dye is an unstable dye, optionally an unstable acid dye. Optionally, an acid dye is, however, a stable acid dye. An “unstable dye” as defined herein is a dye that is chemically or structurally alterable by exposure to heat, light energy, or both, when the dye is not bound to a substrate. Several such dyes are known in the art. An unstable dye optionally includes azo type dyes or unstabilized quinone dyes.

[0037] Optionally, a dye is a static dye. As used herein, the term “static dye” means a dye that does not substantially change color upon exposure to (or being shielded from) ultraviolet (UV) light when the dye is not bound to a substrate.

[0038] In some aspects, a dye is an acid dye. An acid dye is optionally an anthraquinone acid dye, an azo acid dye, a triphenylmethane acid dye or a premetalized acid dye. Illustrative examples of acid dyes include Acid Blue #60, Acid Blue #260 (Blue RL) Acid Red #151 ((5Z)- 5-[(2-methoxy-5-methyl-4-sulfonatopheny)hydrazinylidene]-6-oxonaphthalene-2-sulfonate), Acid Red #407 (i.e., Rubine S3G), Acid Red #1 (i.e., Acid Red G; azophloxine), Acid Black #2, Acid Yellow #23, Acid Yellow #43 (i.e., Yellow R), Acid Orange #144 (i.e., Orange SR 125%) and Acid Violet #17 (i.e., 3-[[4-[[4-(diethylamino)phenyl]-4-[ethyl-[(3- sulfonatophenyl)methyl] azaniumylidene] cyclohexa-2,5 -dien- 1 -ylidene] methyl] -N - ehtylanilino] methyl] benzenesulfonate).

[0039] Static dyes that may be included in a colored polymeric material include, for example, fabric dyes and disperse dyes as well as dyes that are known in the art as being suitable for tinting plastic articles, such as thermoplastic PVC or polyamide articles. Examples of suitable disperse dyes include, but are not limited to, Disperse Blue #3, Disperse Blue #14, Disperse Yellow #3, Disperse Red #13, Disperse Violet #1, Solvent Yellow #3, Solvent Black #3, and Disperse Red #17. The classification and designation of the static dyes are recited herein in accordance with “The Colour Index”, 3^rd edition published jointly by the Society of Dyes and Colors and the American Association of Textile Chemists and Colorists (1971). The term static dye as used herein optionally includes mixtures of static dyes.

[0040] Illustrative examples of static dyes include the water-insoluble azo, diphenylamine and anthraquinone compounds. Illustrative examples include acetate dyes, dispersed acetate dyes, dispersion dyes and dispersol dyes, such as are disclosed in Colour Index, 3^rd edition, vol. 2, The Society of Dyers and Colourists, 1971, pp. 2479 and pp. 2187-2743, respectively. Specific examples of dispersal dyes include Solvent Blue 59 (9, 10-Anthracenedione, 1,4- bis(ethylamino)-), Solvent Red 111 (9,10-Anthracenedione, l-(methylamino)-), Solvent Yellow 160:1 (3-(5-Chloro-2-benzoxazolyl)-7-(diethylamino)-2H-l-benzopyran-2-one), Disperse Orange 47 (lH-Indole-5-carboxylicacid,2-[2-(l,5-dihydro-3-methyl-5-oxo-l-phenyl-4H-pyrazol- 4-ylidene)ethylidene] -2, 3 -dihydro- 1,3, 3 -trimethyl-methyl ester), Disperse Yellow 3 (Acetamide, N-[4-[2-(2-hydroxy-5-methylphenyl)diazenyl]phenyl]-), Solvent Violet 26 (l,4-Diamino-2,3- diphenoxyanthraquinone), Disperse Red 1 (i.e., Scarlet CSB; 4-[(2-Hydroxyethyl)ethylamino]-4'- nitroazobenzene), Disperse Violet 1 (l,4-diamino-9,10-dihydroanthracene-9,10-dione), Solvent Yellow 3 (2-methyl-4-[2-(2-methylphenyl)diazen-l-yl]aniline), Solvent Yellow 93 (i.e., Yellow 3 G; 4-(( 1 ,5-dihydro-3 -methyl-5-oxo- 1 -phenyl-4H-pyrazol-4ylidene)methyl)-2,4-dihydro-5 - methyl-2-phenyl-3H-pyrazol-3-one); Disperse Green 9 (i.e., Green C6B; N-[5-diethylamino)-2- [(3,5-dinitro-2-thienyl)azo]phenyl]acetamide), Disperse Blue 14 (i.e., Subliprint Blue 700141; l,4-bis(methylamino)anthraquinone); and Solvent Black 3 (2,2-dimethyl-6-{2-[4-(2- phenyldiazen-l-yl)naphthalen-l-yl]diazen-l-yl}-2,3-dihydro-lH-perimidine). Other dyes are illustratively those additional dyes found in U.S. Patent No. 7,175,675 and references cited therein.

[0041] A colored or other polymeric material is optionally formed by employing infusion techniques from any of several processes. In some aspects, a dye infused linear polymeric material is formed by employing infusing techniques as described in U.S. Pat. Nos. 6,733,543; 6,749,646; 6,929,666; 6,949,127; 6,994,735; 7,094,263; 7,175,675; 7,504,054; 7,921,680; or 8,206,463. In some aspects, a dye infused linear polymeric material is formed by employing infusing techniques as described in: U.S. Patent Application Publication Nos.: 2008/0067124; 2009/0297829; 2009/0297830; or 2009/0089942.

[0042] An infusion agent is optionally an oxidizing agent, a free radical precursor, or a compound having the formula of Formula I:

R¹ - [(0(CH₂)m)n — ] OR² (I)

[0043] wherein R² and R¹ are each independently H or a Ci-is alkyl, benzyl, benzoyl, or phenyl; n is 1, 2 or 3; and m is any value from 1 to 35. In some aspects, m is 1 to 12. In some aspects, m is 1. Optionally, R¹ denotes H. Optionally, R¹ denotes butyl and R² denotes H. An aromatic R¹ or R² group of Formula I is optionally substituted with 1 to 5 groups selected from halo groups (e.g., chloro, bromo and fluoro), linear or branched C_1-C₉ alkyl groups (e.g., methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl and nonyl), and aromatic groups (e.g., phenyl).

[0044] Specific examples of an infusion agent according to Formula I include 2- methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-isopropoxyethanol, 2-butoxyethanol, 2- phenoxyethanol, 2-benzyloxyethanol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol, dimethoxyethane, diethoxyethane, and dibutoxyethane, ethylene glycol butyl ether, diethylene glycol ethylether, diethylene glycol butylether, propylene glycol propylether, dipropylene glycol propyl ether and tripropylene glycol propylether, or combinations thereof.

[0045] The infusion agent is typically present in the infusion solution in an amount of less than or equal to 50 percent by weight, optionally less than or equal to 30 percent by weight, optionally less than or equal to 25 percent by weight, optionally less than or equal to 20 percent by weight. The infusion agent is optionally present in the solution in an amount of at least 10 percent by weight, optionally at least 15 percent by weight, optionally at least 17 percent by weight. The infusion agent may be present in the infusion solution in an amount ranging from 10 to 30 percent by weight or any value or range therebetween. For example, the infusion agent is optionally present in the infusion solution in an amount from 10 to 30 percent by weight, optionally from 15 to 25 percent by weight, optionally in an amount of from 17 to 20 percent by weight. The percent weights being based on the total weight of the infusion solution.

[0046] An infusion solution optionally includes one or more infusion agents. Optionally, an infusion solution includes 1, 2, 3, 4, 5, 6, or more infusion agents. In some aspects, when more than one infusion agent is present in an infusion solution, there may be infusion agents of more than one type. In some aspects, a first infusion agent is an agent of Formula I, and a second infusion agent is a diol of Formula II:

H — [(0(CH₂)_m)n — ] OH (II)

[0047] wherein n is 1, 2 or 3; and m is any value from 1 to 35. In some aspects, m is 1 to 12. In some aspects, m is any value from 2 to 4. Optionally, m is any value from 2 to 4 and n is 1, 2, or 3. Illustrative agents of Formula II include diethylene glycol, tri ethylene glycol and 1,4 butanediol.

[0048] An infusion agent is optionally present in an infusion agent solution at a concentration of 2.5 to 20, optionally 5 to 12.5, optionally 7.5 to 10 parts by weight (pbw). A second infusion agent is optionally present in an amount identical to a first infusion agent. Optionally, a second infusion agent is present in an amount of 5 to 30, optionally 10 to 25, optionally 15 to 20 pbw.

[0049] An infusion solution optionally includes one or more emulsifiers. Illustrative examples of an emulsifier include ionic or non-ionic emulsifiers, or mixtures thereof. Illustrative examples of an anionic emulsifier include: amine salts or alkali salts of carboxylic, sulfamic or phosphoric acids, for example, sodium lauryl sulfate, ammonium lauryl sulfate, lignosulfonic acid salts, ethylene diamine tetra acetic acid (EDTA) sodium salts, and acid salts of amines, such as, laurylamine hydrochloride or poly(oxy-l,2-ethanediyl), a-sulfo-omega-hydroxy ether with phenol 1 -(methylphenyl)ethyl derivative ammonium salts. An emulsifier is optionally an amphoteric emulsifier illustratively: lauryl sulfobetaine; dihydroxy ethylalkyl betaine; amido betaine based on coconut acids; disodium N-lauryl amino propionate; or the sodium salts of dicarboxylic acid coconut derivatives. Typical non-ionic emulsifiers include ethoxylated or propoxylated alkyl or aryl phenolic compounds, such as octylphenoxypolyethyleneoxyethanol. A specific emulsifier used is diethylene glycol.

[0050] An emulsifier is optionally present in an infusion agent solution in an amount from 0 to 15 weight percent, optionally 7 to 15 weight percent, optionally 10 to 15 weight percent, optionally 0.5 to 5 weight percent, optionally 3 to 4 weight percent.

[0051] An infusion solution optionally includes one or more surfactants.

[0052] An infusion solution optionally includes one or more salts. It was unexpectedly discovered that the inclusion of salt improves the infusion of active agent, optionally dye into or onto a substrate. Particular improvements are observed with salt concentrations of 0.1 to 0.5 g/L. A salt concentration is optionally greater than 0.1 g/L and less than 0.5 g/L. Optionally a salt concentration is 0.1 g/L to 0.3 g/L. A salt concentration is optionally 0.1 g/L, 0.2 g/L, 0.3 g/L, 0.4 g/L, or 0.5 g/L. A salt is optionally a sodium salt, potassium salt, or other. In some aspects a salt is optionally a salt of Na, K, Ca, Mg, or combinations thereof.

[0053] In some aspects, the infusion solution consists or consists essentially of water and a dye selected from the group consisting of Acid Red 407, Acid Blue 260, Acid Orange 144, Acid Red 1, Acid Yellow 43, Disperse Blue 14, Disperse Green 9, Solvent Yellow 93, or Disperse Red 1.

[0054] An infusion solution is optionally at ambient temperature (approximately 25 °C) or heated above ambient temperature. In some aspects, an infusion process includes heating a linear polymeric material alone or in the presence of an infusion solution where heating is to a temperature below the melting temperature of the polymeric material. Optionally, an infusion solution is preheated or heated in the presence of a linear substrate, optionally to any infusion temperature less than 100 °C.

[0055] The systems described herein may be used to impart color or other desired physical or chemical characteristic into a linear polymeric substrate by a process that may include infusing a linear substrate at an infusion temperature. The infusion temperature is optionally below the melting temperature of the linear substrate polymeric material. An infusion temperature is the temperature of the polymeric material during the infusion process. In some aspects, an infusion temperature is at or above the glass transition temperature (Tg) or the polymeric material to be infused. Optionally, an infusion temperature is at or above the Tg and below the melting temperature. For amorphous thermoplastic materials without true melting points, an infusion temperature is optionally above the Tg but is not so high that the article shape is affected. Optionally, an infusion temperature is between 81 °C and 91 °C. Illustratively, for a polyamide thermoplastic material an infusion temperature may be 90 °C to 99 °C. Illustratively, for a PVC thermoplastic material an infusion temperature may be 75 °C to 90 °C. It is appreciated that polymers that may have a lower heat distortion temperature may be infused at a lower temperature. As one example, an infusion temperature of a polyurethane may be about 60 °C. As another example, the infusion temperature may be from 90 °C to 98 °C.

[0056] The linear substrate is optionally formed by immersing a linear polymeric material in an infusion solution for an infusion time where the immersing is done in an element of an infusion system as provided herein. In some aspects, it is appreciated that spraying an infusion solution onto the linear substrate is excluded. An infusion time is optionally any time from <1 second to 120 minutes, or more. In some aspects, an infusion time is optionally from <1 second to 30 minutes, optionally from <1 second to 20 minutes, optionally from 1 second to 10 minutes, optionally from 1 second to 1 minute, optionally from 5 seconds to 1 minute, optionally from 5 seconds to 30 seconds, optionally from 10 seconds to 20 seconds, optionally 2 to 10 seconds, optionally 3 to 6 seconds. An infusion time is optionally 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 or 60 milliseconds. An infusion time is optionally 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, or 30 seconds. In some aspects, an infusion time is less than one min, optionally from 0.01 second to 1 minute, or any value or range therebetween. In some aspects, an infusion time is from 0.1 seconds to 5 seconds or from 0.25 seconds to 3 seconds.

[0057] In some aspects, the infusion time is sufficient to enable the active molecules to penetrate the surface of the linear polymeric material to a depth of less than 1 millimeter. In some aspects, the infusion time is sufficient to enable the active molecules to penetrate the surface of the linear polymeric material to a depth of less than 200 microns. Accordingly, in some aspects, the active molecules penetrate the surface of the linear polymeric material from 1 micron to 1 millimeter, from 5 microns to 500 microns, from 10 microns to 250 microns, or from 20 microns to 200 microns. [0058] The following provides exemplary description of a linear substrate infusion system suitable for infusing an active agent (e.g., dye) into the surface a linear substrate. It is appreciated that one or more of the colored dyes as the active in an infusion solution used in the following description are substitutable with one or more other active agents to be infused into the linear substrate. Throughout this disclosure the infusion system is referenced as having a first colored dye and a second colored dye appreciating that colored dye is equally substitutable with another active agent to be infused into the linear substrate. Limitation of discussion to two colored dyes is for ease of discussion and simplicity. It will be appreciated that aspects of the infusing system may include 3 or more colored dyes by replicating one or more elements of the associated systems of the first or second colored dye for each additional colored dye added to the infusion system.

[0059] FIGS. 1A, IB, and 1C illustrate a schematic layout of the interconnectivity of the infusion system. A generalized infusion system configured for two infusion solution options includes a first dye supply 20 for providing an infusion solution and a second dye supply 30 for providing a second infusion solution. The first dye supply 20 and second dye supply 30 are attached to a first process tank 22 and a second process tank 32 respectively. The process tanks 22, 32 each provide a reservoir of infusion solution for circulation through the infusion system. The first process tank 22 and the second process tank 32 each are fluidly connected to an infusion tank 40. The infusion tank 40 contacts the desired infusion solution with the substrate to color the outer surface of the substrate by infusing the active material (e.g., the dye) into the substrate surface. Upon exiting the infusion tank 40, the infusion solution is returned to the first process tank 22 or the second process tank 32 for the respective color from which the colored dye originated. Propulsion of the first infusion solution and the second infusion solution is provided by a first dye pump 24 and a second dye pump 34 respectively. A process tank is optionally formed of one or more non-reactive materials, optionally stainless steel. A non-reactive material is one that will not cause degradation of an infusion solution or any component therein or the linear substrate during an infusion time.

[0060] The infusion system is unique in providing the ability to change the active material that is infused into the linear substrate during processing of the linear substrate. Specifically, in one example, the infusion system may be converted from creating blue substrate to creating green substrate while the system is operating. There is no requirement to terminate the infusion system operation, clean the equipment, and re-feed the substrate into the equipment when a change of active is desired. A single run of substrate, from a pre-manufactured spool (or other source) or as the output of a substrate forming line, may have the color changed from red to green, for example, without stopping the processing line. For example, change of one active or active combination to another active or active combination is achievable in 1 second to 2 minutes such that the scrap material produced during the changeover is minimized.

[0061] In one or more aspects, the first process tank 22 and the second process tank 32 are each connected to respective heating loops. The heating loops raise the temperature of the first infusion solution and the second infusion solution to the desired set point for introduction to the infusion tank 40 and coloring of the linear substrate. Each heating loop may comprise an in-line heater to raise the temperature of the first infusion solution or the second infusion solution respectively during passage of the first infusion solution or the second infusion solution through the heating loop. A heating loop is optionally 1 to 10 feet long, optionally 2 to 4 feet long. It is appreciated that the length of the heating loop need only be sufficient to heat the infusion solution or portion thereof to a desired temperature.

[0062] In one or more aspects, the first process tank 22 and the second process tank 32 may be heated tanks. In further aspects, the first process tank 22 and the second process tank 32 may each comprise an agitator or mixer to maintain a uniform temperature and mixture throughout the infusion solvent within the first process tank 22 or the second process tank 32. In example, a process chamber has a length of 7 feet and an internal diameter of 1.5 inches producing a system with a fluid capacity of 0.65 gallons. The dimensions of the process chamber are for exemplary purposes alone, and other dimensions are contemplated.

[0063] In further aspects, a filter may be included in the heating loop and/or between the heating loop and infusion tank 40 and/or between the infusion tank 40 and the process tank 22, 32. When included, the filter serves to filter and remove sediment or unwanted particles that enter the infusion solvent during the coloring operation. An illustration of a filter includes standard bag filters such as Trade Size 3, 316 stainless steel, top feed.

[0064] The heating loop allows circulation of the infusion solvent when not being provided to the infusion tank 40. The heating loop for the first infusion solution includes a first diverter valve 26 and the heating loop for the second infusion solution includes a second diverter valve 36. The first diverter valve 26 and the second diverter valve 36 direct the respective infusion solution on a recirculation pathway in the heating loop when in a first position and direct the infusion solution away from the heating loop to the infusion tank 40 when in a second position. Although various aspects described herein include two process tanks and two heating loops, it is contemplated that a greater or fewer number of process tanks and respective heating loops may be included, depending on the particular embodiment.

[0065] Referring to FIGS. 1A, IB, and 1C which illustrate a schematic layout of a generalized infusion system, the infusion system further comprises a solvent loop 50. The solvent loop 50 is fluidly connected to the infusion tank 40. The solvent loop 50 provides clean solvent (e.g., without an active material, such as a dye) to flush the infusion tank 40 when changing from one infusion solution to a different infusion solution. Flushing the infusion tank 40 prevents improper coloration of the linear substrate and contamination of the actives in the first process tank 22 and the second process tank 32. Optionally, the second infusion solution is used to flush the first infusion solution from the process chamber without a clean solvent flush, which may increase the speed of infusion solution turnover. The solvent loop 50 optionally includes a solvent recovery tank 52, a filter system 54, a clean solvent tank 56, and at least one supply pump 58.

[0066] The solvent recovery tank 52 is fluidly connected to an outlet of the infusion tank 40. Infusion solvent, having passed through the infusion tank 40, is recovered in the solvent recovery tank 52 for further processing and cleaning. In one exemplary aspect, a solvent recovery tank is formed of a nonreactive material such as stainless steel. A solvent recovery tank 52 has a volume sufficient to recover a needed amount of infusion solvent, optionally 60 gallons. Such a solvent recovery tank optionally has a shape that is cylindrical, conical or combinations thereof.

[0067] The filter system 54, as a subcomponent of the solvent loop 50, removes contaminants from the spent infusion solvent in the solvent recovery tank 52. In one or more aspects, the filter system 54 comprises a bag filter 154 and a carbon filter 254 fluidly connected to the solvent recovery tank 52. The bag filter 154 functions to remove solid or particulate materials from the spent solvent. Similarly, the carbon filter 254 functions to remove dissolved active material from the spent infusion solvent. The filter system 54 may also include a filter pump 354 to provide a head pressure for transit of the spent solvent through the bag filter 154 and/or carbon filter 254.

[0068] Passage of the spent infusion solvent through the filter system 54 returns the infusion solvent to a clean state. The cleaned infusion solvent is conveyed to the clean solvent tank 56 which is fluidly connected to the filter system 54. The clean solvent tank 56 serves as a reservoir of infusion solvent to be provided to the infusion tank 40 during transitions from one active material(s) to a different active material(s). A clean solvent tank is optionally made of a nonreactive material, optionally stainless steel, and is of a size suitable to hole a desired amount of infusion solvent. In example, a clean solvent tank is a 60 gallon tank of stainless steel of a shape that is cylindrical, conical, or combination thereof.

[0069] In some aspects, infusion solvent is subjected to a cleaning or modification step. A cleaning or modification step may be achieved through the use of a carbon filter, distillation system, other system, or combinations thereof. Modification of a system may be that a dye, or other additive, is intended such that an initial dye or other active agent may be substituted with a subsequent dye or other active agent. In some aspects, the dye and optional other active agents are separated from the other components of the infusion solvent (e.g., the water, acid, carrier, diol, or optional surfactants). Such a separation is environmentally favorable in that it allows for re use of the non-dye components of the bath, for example with another dye or dyes, or with a fresh dye(s), or as a rinse composition for rinsing dyed plastic articles removed from the dye bath. In addition, the dye separation method may be performed if the dye of the dye bath has been damaged, such as oxidized or otherwise denatured (e.g., due to overheating due to a temperature spike).

[0070] The dye separation process may be performed by contacting the dye bath with particulate activated carbon, flowing the infusion solvent into a distillation chamber, and then isolating desired materials or components therefrom. The desired components may then be reused as desired. The infusion solvent, in some aspect, may be contacted with the activated carbon by passing the infusion solvent continuously through a bed or column optionally containing activated carbon.

[0071] The clean solvent tank 56 is fluidly connected to an inlet of the infusion tank 40. To convey the clean solvent from the clean solvent tank 56 to the infusion tank 40, at least one supply pump 58 is provided. The supply pump 58 provides motive force to convey the solvent to the infusion tank 40, through the infusion tank 40, and to the solvent recovery tank 52. A supply pump has sufficient power to move infusion solvent throughout the system or portion thereof. Optionally, a pump of 0.5 horsepower with a flow rate of up to 25 gallons per minute (gpm) is sufficient. In some aspects, the flow rate is set to 1-2 gpm.

[0072] Further, the solvent loop 50 may include a solvent heater to raise the temperature of the infusion solvent to the desired set point for introduction to the infusion tank 40. In one or more aspects, an in-line heater is provided between the clean solvent tank 56 and the infusion tank 40 to heat the infusion solvent in an on-demand fashion. In further aspects, a submerged heater is provided within the clean solvent tank 56 to heat and hold the bulk clean solvent within the clean solvent tank 56. In some aspects, an in-line solvent heater is used, optionally with a power of 8kW to 15kW.

[0073] Referring still to FIGS. 1A, IB, and 1C, the infusion system includes a plurality of valves to control the flow of the first infusion solution from the first process tank 22, the second infusion solution from the second process tank 32, and the flow of solvent from the clean solvent tank 56 to the infusion tank 40 as well as away from the infusion tank 40 to their respective reservoirs (the first process tank 22, the second process tank 32, and the solvent recovery tank 52). Specifically, a first infusion solution inlet valve 60 controls flow of the first infusion solution from the first process tank 22 to the infusion tank 40 and a first infusion solution outlet valve 62 controls flow of the first infusion solution from the infusion tank 40 back to the first process tank 22. Similarly, a second infusion solution inlet valve 70 controls flow of the second infusion solution from the second process tank 32 to the infusion tank 40 and a second infusion solution outlet valve 72 controls flow of the second infusion solution from the infusion tank 40 back to the second process tank 32. Finally, a solvent inlet valve 80 controls flow of the clean solvent from the clean solvent tank 56 to the infusion tank 40 and a solvent outlet valve 82 controls flow of the spent solvent from the infusion tank 40 to the solvent recovery tank 52. A valve 80 is optionally a standard industrial ball valve of 316 stainless steel. Pneumatic or manual actuation valves may be used, among others.

[0074] In operation, the infusion system allows running changes to the color of dye (or other active change) infused into the linear substrate surface. FIG. 1 A illustrates an exemplary infusion system and associated valves positioned for application of the first infusion solution to the linear substrate in the infusion tank 40. Specifically, the first infusion solution valve 60 and the first infusion solution outlet valve 62 are in an open position whereas the second infusion solution inlet valve 70, the second infusion solution outlet valve 72, the solvent inlet valve 80, and the solvent outlet valve 82 are in all a closed position. In the configuration for application of the first infusion solution to the linear substrate in the infusion tank 40 the first infusion solution is provided to the infusion tank 40 and returned to the first process tank 22. Within the infusion tank 40 the first colored dye contained in the first infusion solution is infused into the surface of the linear substrate.

[0075] During application of the first infusion solution to the linear substrate, the heating loop for the second process tank 32 is activated to raise the temperature of the second infusion solution to the desired temperature set point for infusion of the active into the linear substrate. The heating loop is optionally activated in advance of the change from the first infusion solution to the second infusion solution to provide an opportunity to fully heat the second infusion solution and negate the need to cease operation of the infusion system during the infusion solution conversion.

[0076] To initiate a change from the first infusion solution to the second infusion solution, the infusion tank 40 is optionally flushed with solvent to remove residual of the first infusion solution. FIG. 1 B illustrates an exemplary infusion system and associated valves positioned for flushing or otherwise changing the type of infusion solution in the infusion tank 40. Specifically, the first infusion solution inlet valve 60 is closed while the first infusion solution outlet valve 62 remains open. Concurrently, the solvent inlet valve 80 is opened to initiate flow of the solvent. The solvent acts to flush the infusion tank 40 of the residual first infusion solution. After a timed period, calculated to substantially flush all the residual first infusion solution from the infusion tank 40, the first infusion solution outlet valve 62 is closed and the solvent outlet valve 82 is opened. This configuration provides a solvent loop to flush the infusion tank 40 of any residual first infusion solution. By adjusting the first infusion solution outlet valve 62 and the solvent outlet valve 82 after the timed period substantially all the residual first infusion solution is returned to the first process tank 22 and a minimal amount is flushed out with the solvent into the solvent recovery tank 52. It is desirable to minimize flow of infusion solution into the solvent recovery tank 52 because the filter system 54 must remove any colored dye or other active material which is collected by the solvent.

[0077] FIG. 1C illustrates the infusion system and associated valves positioned for application of the second infusion solution to the linear substrate in the infusion tank 40. Upon sufficient flushing of the infusion tank 40 with the solvent, the solvent inlet valve 80 is closed while the solvent outlet valve 82 remains open. Concurrently, the second infusion solution inlet valve 70 is opened to initiate flow of the second infusion solution from the second process tank 32. The second infusion solution acts to flush the infusion tank 40 of the residual solvent and fully fill the infusion tank 40 with the second infusion solution. After a timed period, calculated to flush all the residual solvent from the infusion tank 40, the solvent outlet valve 82 is closed and the second infusion solution outlet valve 72 is opened. By adjusting the solvent outlet valve 82 and the second infusion solution outlet valve 72 after the timed period, all the residual solvent is returned to the solvent recovery tank 52 with only a minimal amount flushed out with the solvent into the solvent recovery tank 52.

[0078] The infusion system can be provided with various electronic, mechanical, or other controls for controlling or adjusting one or more parameters of the infusion process or the system itself. For example, an interface for operating the system can be provided. The interface may comprise a graphical user interface (GUI) to allow an operator to monitor and/or adjust process parameters. Illustrative examples of process parameters include a) infusion solution temperature in tank, b) infusion solution temperature in process chamber, c) solvent flow rate, d) position of valves (e.g. open, closed, intermediate), e) speed of linear substrate moving through process chamber, f) control pump on/off, g) infusion solution level in process tanks, h) solvent level in solvent recovery tank, i) solvent level in clean solvent tank, j) solvent level in process tanks, k) solvent temperature in recovery tank, 1) temperature setting of process tanks (thermocouple), m) linear substrate footage counter, n) color concentrate level meter, among others.

[0079] One or more of several temperature, color, infusion level, linear substrate or other sensors are optionally included in the infusion system. Such sensors may be positioned at any desired location such as within the infusion tank, within any supply line or other portion, any tank, or within optical, thermal, or electrical contact with a linear substrate, infusion solution, or other component.

[0080] The process of infusing a linear substrate (e.g., a hose as one example of a preformed linear substrate formed of a polymeric material) may include either supplying the linear substrate from a storage reel or other stored form and moving the linear substrate into the infusion system infusion tank in a longitudinal direction. In some aspects, the linear substrate may also be provided as a direct output of the linear substrate manufacturing process such as off an extruder or prior to cooling or storage of the linear substrate. Passage of the linear substrate through the infusion tank can be set at any desired speed so long as the speed is not so great so as to reduce the residence time in the infusion solvent within the infusion tank to a point at which insufficient infusion is achieved. In one example, the speed of the linear substrate moving through the infusion tank can be illustratively set at 10 ft/min to 1500 ft/min, optionally 100 ft/min to 500 ft/min.

[0081] In embodiments, linear substrate is maintained in the infusion tank 40 for an infusion time sufficient to ensure that the active material in the infusion solution is infused into the linear substrate to a desired depth, hue, opacity or other characteristic. In one example, the residence time can range from a fraction of a second to many seconds. A residence time is optionally 0.1 second to 10 seconds, optionally 0.1 second to 8 seconds, optionally 0.25 seconds to 1 second, optionally 0.1 second to 0.25 seconds, optionally 0.1 second to 0.5 seconds, optionally 1 second to 3 seconds. In embodiments, the first process tank 22 and the second process tank 32 are optionally heated to raise the temperature of the first infusion solution and second infusion solution respectively. In one example, the infusion solution is heated to a temperature of 80 °C to 99.9 °C. In another example, the infusion solution can be heated to 90 °C to 99.9 °C. Optionally, the infusion solution is heated as close as possible to the boiling temperature of water at 100 °C (1 atm). In one specific example, the infusion solution is heated to approximately 99 °C.

[0082] The first dye pump 24 and second dye pump 34 pump the first infusion solution from the first process tank 22 and the second infusion solution from the second process tank 32 respectively to the infusion tank 40 and back to the first process tank 22 or second process tank 32. The passage of the first infusion solution or the second infusion solution through the infusion tank 40 contacts the colored dyes or other active materials in the infusion solution to the linear substrate and results in the dyeing of the linear substrate by infusion of the dye(s) into the surface of the linear substrate. It is also contemplated that the first process tank 22 and the second process tank 32 are connected to the first dye supply 20 and the second dye supply 30 respectively, which are configured to add additional colored dye as needed to the first and second process tanks 22, 32. However, other methods of colored dye addition are also contemplated. Once the linear substrate exits the infusion tank 40, the linear substrate can then be transferred to one or more washing stations to remove excess infusion solution. [0083] With reference to FIGS. 2A, 2B, 2C, and 2D, an aspect of the infusion tank 40 is illustrated for a single color system. As depicted in FIG. 2A, the infusion system includes the infusion tank 40 and an immersion system 200. The infusion tank 40 includes an immersion reservoir 202 including an open end 204. In embodiments, the immersion reservoir 202 is in fluid communication with various aspects of the infusion system (e.g., the first process tank 22, the second process tank 32, clean solvent tank 56, etc.) described herein with respect to FIGS 1A, 1C, and ID. In embodiments, the immersion reservoir 202 is pre-filled with a liquid infusion solution 208 via components other than those described herein with respect to FIGS. 1 A, IB, and 1C. For example, in embodiments, the immersion reservoir 202 is pre-filled with the liquid infusion solution 208 prior to use.

[0084] In the depicted embodiment, the immersion reservoir 202 is a substantially parallelepiped-shaped container, though reservoirs having alternative forms are contemplated and within the scope of the present disclosure. The open end 204 comprises an opening through which a linear substrate 206 may be immersed into the liquid infusion solution 208 contained in the immersion reservoir 202. In the depicted embodiment, the immersion reservoir 202 contains a volume of the liquid infusion solution 208 such that the liquid infusion solution 208 fills the immersion reservoir 202 to a fill level L_f.

[0085] In embodiments, the liquid infusion solution 208 is heated to an infusion temperature (e.g., via the heating loops associated with one or more of the first and second process tanks 22 and 22 described herein) prior to accumulating within the immersion reservoir 202. In embodiments, the immersion reservoir 202 comprises one or more heating elements (e.g., induction coil, burner, or the like) such that the liquid infusion solution 208 is heated to the infusion temperature while being disposed in the immersion reservoir 202. In embodiments, the immersion reservoir 202 is in fluid communication with one or more of the first process tank 22 and the second process tank 24 described herein and includes one or more sets of inlets and outlets (not depicted) to facilitate circulation of fluids (e.g., infusion solution, solvent, etc.) therethrough. In embodiments, the immersion reservoir 202 is pre-filled with the liquid infusion solution 208 and certain components of the infusion system described herein with respect to FIGS. 1 A, IB, and 1C (e.g., associated with the first process tank 22, second process tank 24, and the solvent tanks 52 and 56) are omitted. In embodiments, the immersion reservoir 202 is pre-filled with the liquid infusion solution 208 rather than having the liquid infusion solution circulated therethrough. [0086] In embodiments, the infusion system includes an acoustic mixing system (not depicted) that mixes the liquid infusion solution 208 within the immersion reservoir 202. For example, in embodiments, the immersion reservoir 202 is disposed on a vibrating platform (not depicted) that imparts vibrational energy on the immersion reservoir 202 to generate a plurality of micro-mixing zones within the liquid infusion solution 208. The immersion reservoir 202 may be vibrated to match the impedance of the liquid infusion solution 208 to generate an acoustic resonance in the liquid infusion solution 208 to improve mixing efficiency. Such acoustic mixing may maintain homogeneity of the composition of the liquid infusion solution 208 to ensure uniform infusion of the linear substrate 206. Any suitable form of acoustic mixing system may be used.

[0087] Referring still to FIG. 2A, the immersion system 200 includes one or more linear substrate guides 210 that convey the linear substrate in a feed direction 212 over and through the immersion reservoir 202. FIG. 2A depicts the immersion tank 40 in a starting position in which the linear substrate 206 is not immersed in the liquid infusion solution 208. In the starting position depicted in FIG. 2A, the linear substrate 206 extends in the feed direction 212 and substantially parallel to the fill level L_f of the liquid infusion solution 208. In embodiments, when in the starting position, an entirety of the linear substrate 206 is disposed above (e.g., in the positive z-direction of the coordinate axes depicted in FIG. 2A) the open end 204 of the immersion reservoir 202. In embodiments, the linear substrate 206 is unwound from a spool (not depicted) disposed upstream of (e.g., in the negative x-direction of the coordinate axes depicted in FIG. 2A) the infusion tank 40 for infusion. In embodiments, the linear substrate 206 is provided as a direct output of the linear substrate manufacturing process such as off an extruder (not depicted) disposed upstream of the infusion tank 40. It should be understood that the feed direction 212 may extend in a non parallel direction to the fill level L_f in alternative embodiments. Moreover, embodiments are also envisioned where the linear substrate 206 extends along a meandering path above the immersion reservoir 202.

[0088] The one or more linear substrate guides 210 maintain the positioning of the linear substrate 206 along a desired feed path (e.g., through the immersion reservoir 202) and maintain conveyance of the linear substrate 206 at a desired feed rate in the feed direction 212. In the depicted embodiment, the one or more linear substrate guides 210 comprise pairs of rollers and the linear substrate 206 extends between the rollers of each pair of rollers. In embodiments, at least one of the one or more linear substrate guides 210 includes only a single roller. It should be appreciated that any suitable guiding mechanism (e.g., actuator or stationary groove) may be used for any combination or sub-combination of the one or more linear substrate guides 210. Moreover, embodiments are envisioned where subsets of the one or more linear substrate guides 210 have different constructions from one another. For example, in one embodiment, a first grouping of the one or more linear substrate guides 210 are pairs of rollers, while a second grouping of the one or more linear substrate guides 210 are a single roller.

[0089] In embodiments, the one or more linear substrate guides 210 includes a first linear substrate guide 214 disposed proximate to a first end of the immersion reservoir 202 and a second linear substrate guide 216 disposed proximate to a second end of the immersion reservoir 202. In embodiments, the first and second linear substrate guides 214 and 216 remain stationary throughout the process of immersing the linear substrate 206 into the liquid infusion solution 208 described herein. In embodiments, one or more of the first and second linear substrate guides 214 and 216 is rotated via an actuator (not depicted) to determine a feed rate of the linear substrate 206 through the infusion tank 40. Passage of the linear substrate 206 through the infusion tank 40 can be set at any desired speed. In embodiments, the feed rate of the linear substrate 206 is set depending on the configuration of the immersion system 200, as described herein. In embodiments, the speed of the linear substrate 206 moving through the infusion tank 40 can be illustratively set at 50 ft/min to 400 ft/min, depending on the configuration of the immersion system 200.

[0090] In embodiments, the feed rate at which the linear substrate 206 travels through the immersion system 200 is not set by the first and second linear substrate guides 214 and 216, but rather a production rate of the linear substrate 206. For example, in embodiments, a linear substrate source (e.g., an extruder or spool of precursor linear substrate (not depicted)) is disposed upstream of the infusion tank 40 and linear substrate 206 is fed into the infusion tank 40 from the linear substrate source (e.g., either directly from the extruder or indirectly via a supply spool receiving the linear substrate 206 from the linear substrate source). In embodiments, the linear substrate source may vary in the rate of production of the linear substrate 206 (e.g., in response to operator production needs or mode of operation of the extruder). The rate at which the linear substrate 206 is fed through the infusion tank 140 may vary (e.g., by adjusting the configuration of the immersion unit 218 described herein) responsive to variations of the production rate of the linear substrate source. In embodiments, the linear substrate may 206 accumulate externally to the infusion tank 140 (e.g., via a spool disposed upstream or downstream of the infusion tank 140). For example, in embodiments, an output of a linear substrate source may be fed onto a supply spool, which is coupled to the infusion tank 206. In embodiments, the linear substrate 206 is accumulated after infusion in the infusion tank 140 via an output spool disposed downstream of the second linear substrate guide 216.

[0091] In embodiments, one or more of the rate at which the linear substrate 206 is fed through the infusion tank 140 and the rate at which the linear substrate 206 is accumulated before and/or after the infusion tank 140 is adjusted responsive downstream use needs. In response to an increased need for the linear substrate 206, for example, the configuration of the immersion system 200 (e.g., via adjusting the configuration of the immersion unit 218 described herein) may be adjusted to operate using an increased feed rate (e.g., to provide the same immersion time at the increased feed rate). In embodiments, the increased feed rate may be a result of an increased output rate of a linear substrate source or a rate at which the linear substrate 216 is unwound from a collection spool disposed upstream of the infusion tank 140. Adjustments may also be made to respond to periods of reduced demand for the linear substrate 206. For example, the rate at which the linear substrate 206 is supplied to the infusion tank 140 may be lowered and the immersion system 140 may be adjusted to maintain an immersion time of the linear substrate 206 at the lowered feed rate.

[0092] Referring still to FIG. 2A, the immersion system 200 includes an immersion unit 218 including one or more linear substrate guide supports 220. In embodiments, the one or more linear substrate guides 210 includes one or more movable linear substrate guides. In the depicted embodiment, for example, the immersion unit 218 comprises movable linear substrate guides 222, 224, 226, 228, 230, and 232; and each one of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 is attached to one of the one or more linear substrate guide supports 220. In embodiments, the one or more linear substrate guide supports 220 are movable or adjustable so as to effectuate selective movement of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 in a direction perpendicular to the feed direction 212 (e.g., in the positive and negative z- directions depicted in FIG. 2A), or other suitable direction that is different than the feed direction 212. For example, in embodiments, the one or more linear substrate guide supports 220 are extendable arms (e.g., including an inner component that is telescopically extendable within an outer component) and the immersion unit 218 comprises a one or more actuators (e.g., translation motors, pneumatic cylinder, or other suitable actuator, not depicted) that extend and retract the linear substrate guide supports 220 in a desired pattern to facilitate immersing the linear substrate 206 into the liquid infusion solution 208.

[0093] For example, FIG. 2B depicts the immersion tank 40 during a starting point of infusing the linear substrate 206 in the liquid infusion solution 208. As shown, a first linear substrate guide support of the one or more linear substrate guide supports 220, to which the movable linear substrate guide 222 is attached, is extended. For example, an actuator associated with the immersion unit 218 may extend a first one of the one or more linear substrate supports 220 such that the movable linear substrate guide 222 is immersed in the liquid infusion solution 208 by a distance 234 beneath the fill level L_f. As a result, the portion of the linear substrate 206 in contact with the movable linear substrate guide 222 is also immersed in the infusion solution 208. An immersed portion 236 of the linear substrate 206 is guided via the first linear substrate guide 214 and the movable linear substrate guide 222 into the liquid infusion solution 208. The immersed portion 236 is immersed in the liquid infusion solution 208 for an immersion time that is dependent on the distance 234 and the feed rate of linear substrate 206 (e.g., dependent on the rate at which the linear substrate 206 is unwound from a spool or a rate at which the linear substrate 206 is fed from an extruder).

[0094] As depicted in FIG. 2B, the immersion reservoir 202 optionally comprises one or more tank rollers 238 disposed therein. In the depicted embodiment, the one or more tank rollers 238 are each positioned at the same height in the immersion reservoir 202 beneath the fill level L_f of the liquid infusion solution 208, though the one or more tank rollers 238 may be positioned at different heights in different implementations. As depicted, the one or more tank rollers 238 are horizontally distributed along the feed direction 212 such that each of the one or more tank rollers 238 is positioned between two of the one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232. In embodiments, each one of the one or more tank rollers 238 is positioned halfway between successive ones of the one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232 in the feed direction 212. Such a configuration facilitates the portions of the immersed portion 236 of the linear substrate 206 that are not in contact with the movable linear substrate guide 222 travelling parallel to one another on either side thereof, thereby facilitating precise control of the immersion time of the immersed portion 236. Moreover, the one or more tank rollers 238 facilitate the immersed portion 236 following a meandering feed path when multiple ones of the one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232 are immersed in the liquid infusion solution 208 to increase the immersion time of the immersed portion 236 while holding the feed rate constant.

[0095] Various different combinations of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may be immersed in the liquid infusion solution 208 via the immersion unit 218 to change the feed path of the linear substrate 206 and the immersion time of the immersed portion 236. It should be understood that, in embodiments, the immersion unit 218 comprises a single movable linear substrate guide and that the feed path may be adjusted by altering the depth that that movable linear substrate guide is immersed in the liquid infusion solution 208. FIG. 2C depicts an instance where each of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 are immersed in the liquid infusion solution 208 by the distance 234 described with respect to FIG. 2B. For example, after the starting point of the immersion process depicted in FIG. 2B, the actuators of the immersion unit 218 may be activated to extend the one or more linear substrate guide supports 220 to render the immersion system 200 in the state depicted in FIG. 2C. As depicted, the immersed portion 236 follows a meandering feed path within the immersion reservoir 202 such that a much greater length of the linear substrate 206 is immersed in the liquid infusion solution 208 in the state depicted in FIG. 2C as compared to the starting point depicted in FIG. 2B.

[0096] In embodiments, the feed rate of the linear substrate 206 is increased in proportion to the length of the immersed portion 236. That is, the feed rate of the linear substrate 236 may be proportional to the number of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 that are immersed in the liquid infusion solution 208. For example, when the immersion system 200 is in the state depicted in FIG. 2B, the feed rate of the linear substrate 206 may be less than when the immersion system 200 is in the state depicted in FIG. 2C such that the immersion time that the immersed portion 236 is maintained within the liquid infusion solution 208 is the same. In embodiments, the particular combination of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 that is used to immerse the linear substrate 206 in the liquid infusion solution 208 may be selected in response to changes in the feed rate of the linear substrate 206 (e.g., resulting from a change in output rate of an extruder) to maintain a consistent immersion time. [0097] It should be understood that any combination of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may be immersed in the liquid infusion solution 208 to alter the length and feed path of the immersed portion 236. In one example, the movable linear substrate guide 224 and the movable linear substrate guide 228 may be immersed in the liquid infusion solution 208 to provide an immersed portion 236 having a length that is between the lengths depicted in FIGS. 2B and 2C. Moreover, it should be understood that the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may be arranged at different heights from one another, irrespective of whether are movable linear substrate guides 222, 224, 226, 228, 230, and 232 are immersed in the liquid infusion solution 208. In embodiments, the linear substrate 206 does not necessarily follow a feed path that is parallel to the surface of the liquid infusion solution 208 at the fill level L_f. Moreover, embodiments are also envisioned where the movable linear substrate guides 222, 224, 226, 228, 230, and 232 are also movable in directions other than perpendicular to the feed direction 212. For example, in embodiments, each of the one or more linear substrate guide supports 220 is disposed on a movable assembly (e.g., a gantry system or a sliding arm) that facilitates movement along the feed direction 212 to provide further adjustability of the feed path of the immersed portion 226. In embodiments, each of the one or more linear substrate guide supports 220 includes an articulating arm or the like with one or more rotation joints that facilitates independent mobility of each of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 in three dimensions. In embodiments, each of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 is rotatable such that the feed path of the immersed portion 236 may be adjusted in a plane parallel to the feed direction 212 within the liquid infusion solution 208. In embodiments, the immersion tank 202 is vertically movable (e.g., in the z-direction depicted in FIGS. 2B and 2C) to facilitate adjustment of the distance 234 that the linear substrate 236 extends into the liquid infusion solution 208.

[0098] In embodiments, the immersion unit 218 comprises an actuator associated with each linear substrate guide of the one or more linear substrate guides 210 to facilitate adjusting an immersion time that the immersed portion 236 of the linear substrate 206 is immersed in the liquid infusion solution 208. The immersion time may be adjusted by altering a configuration of the one or more linear substrate guides 210. In the depicted example, moving the linear substrate 206 using the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may include immersing any number and/or combination of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 into the liquid infusion solution 208. For example, only a first one of the linear substrate guides 222, 224, 226, 228, 230, and 232 may be immersed in the liquid infusion solution 208 such that the immersed portion 236 has a relatively short immersion time (e.g., as depicted in FIG. 2B). While holding the feed rate of the linear substrate 206 constant, the immersion time of the immersed portion 236 may be lengthened by immersing additional ones of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 into the liquid infusion solution 208.

[0099] In embodiments, the configuration of the one or more linear substrate guides 210 may be adjusted in response to various operating conditions. For example, in embodiments, the configuration of the one or more linear substrate guides 210 is adjusted based on an identity of an active molecule in the liquid infusion solution. Certain active molecules may require greater immersion times than others, and so a greater number of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may be immersed in the liquid infusion solution 208 to increase the immersion times when those active molecules are in the liquid infusion solution. In another example, the configuration of the one or more linear substrate guides 210 is adjusted responsive to a change in a rate at which the linear substrate is conveyed in the first direction (e.g., responsive to a feed rate by an extruder). In another example, the configuration of the one or more linear substrate guides 210 is adjusted based on the dimensions of the immersion reservoir 202. As described herein, different infusion tanks may be disposed beneath the immersion unit 218. Accordingly, if an infusion tank having a smaller immersion reservoir 202 is disposed beneath the immersion unit 218, a lesser number of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may be immersed in the liquid infusion solution 208. In embodiments, the distance 234 beneath the fill level LF that the movable linear substrate guides 222, 224, 226, 228, 230, and 232 are immersed in the liquid infusion solution 208 may be adjusted to alter the immersion time. In another example, the configuration of the one or more linear substrate guides 210 is adjusted responsive to a temperature of the linear substrate 206. In an example, a lesser number of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may be immersed in the liquid infusion solution 208 when the temperate of the linear substrate 206 is relatively high. In embodiments, a number of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 that are immersed in the liquid infusion solution 208 is based on a plurality of temperature thresholds of the linear substrate 206 (e.g., one of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may be removed from the liquid infusion solution 208 when the linear substrate 206 is above a first threshold, two of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 may be removed from the liquid infusion solution 208 when the linear substrate 206 is above a second threshold, and so on).

[00100] FIG. 2D depicts a cross sectional view of the movable linear substrate support guide 222 through the line 2D-2D of FIG. 2C. As depicted, the movable linear substrate support guide 222 comprises a pair of rollers including a first roller 240 and a second roller 242 that are attached to one of the one or more linear substrate guide supports 220 via a connection assembly 244. In the depicted embodiment, the connection assembly 244 comprises support arms 246 and 248 extending from an end of the linear substrate guide support 220. A mounting space 250 extends between the support arms 246 and 248. The first roller 252 is rotatably coupled to the support arms 246 and 248 via a first rod 252 extending between the support arms 246 and 248. The second roller 254 is rotatably coupled to the support arms 246 and 248 via a second rod 254 extending between the support arms 246 and 248. In embodiments, the first and second rollers 240 and 242 comprise openings (not depicted) through which the first and second rods 252 and 254 extend such that the first and second rollers 242 and 248 are rotataby supported on the linear substrate guide support 220 (e.g., via bearing assemblies).

[00101] As depicted in FIG. 2D, the first roller 240 includes a first concave surface 256 and the second roller 242 includes a second concave surface 258. The first and second concave surfaces 256 and 258 face one another and delineate a support cavity 260 through which the linear substrate 206 extends. The first and second concave surfaces 256 and 258 beneficially maintain the linear substrate 206 within the support cavity 260 and prevent the linear substrate 206 from sliding out of engagement with the movable linear substrate guide 222. While the first and second rollers 240 and 242 comprise the first and second concave surfaces 256 and 258 that follow a single curved contour, it should be appreciated that embodiments are also envisioned where the first and second rollers 240 and 242 include more complex profiles. For example, in embodiments, the surfaces delineating the support cavity 260 may include a notch, groove, or the like through which the linear substrate 206 extends.

[00102] Use of the pair of rollers for the movable linear substrate guide 222 beneficially facilitates switching between the different operational states of the immersion system 200 described herein with respect to FIGS. 2A, 2B, and 2C. In embodiments, for example, when the movable linear substrate guide 222 is not immersed in the liquid infusion solution 208 (e.g., when in the starting position depicted in FIG. 2A), the linear substrate 206 may be supported by the second roller 242 to maintain positioning thereof. When the movable linear substrate guide 222 is immersed in the liquid infusion solution 208, the linear substrate 208 may be supported by the first roller 240 (e.g., from above). As such, depending on the operational state of the linear substrate guide support 220 to which a particular one of the movable linear substrate guides 222, 224, 226, 228, 230, and 232 is attached, a different one of the rollers therein may serve as a primary support surface of the linear substrate 206. The multiple support surfaces provided by the pair of rollers beneficially facilitates supporting the linear substrate 206 from multiple different directions when the immersion system 200 is placed in different configurations. It should be appreciated that embodiments are also envisioned where the movable linear substrate guide 222 is structured differently than depicted in FIG. 2D. For example, in embodiments, the movable linear substrate guide 222 comprises more than two support elements (e.g., three or more rollers) to facilitate mobility of the movable linear substrate guide 222 in more than two directions. In embodiments, one of the rollers of the movable linear substrate guide 222 may be separately supported within the immersion reservoir 202 (see FIG. 2A).

[00103] In embodiments, the one or more tank rollers 238 attached to the immersion reservoir 202 comprise similar concave profiles as the first and second rollers 240 and 242 of the movable linear substrate guide 222. In embodiments, the first roller 240 and the second roller 242 are vertically separated from one another (e.g., in the Z-direction depicted in FIG. 2D) such that an outer surface of the linear substrate 206 (e.g., disposed proximate to the second concave surface 258 in FIG. 2D) is exposed within the support cavity 260. Such exposure may beneficially ensure that a maximum extent of the outer surface area of the linear substrate 206 is exposed to the liquid infusion solution 208 to facilitate uniform infusion. In embodiments, the one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232 and tank rollers 238 are positioned so as to contact different segments of the linear substrate 206. If the same portion of the outer surface area of the linear substrate 206 contacted each one of the one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232, for example, such a portion may not be infused to the same extent as such un-contacted portions, leading to un-uniform infusion. Accordingly, the one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232 and the tank rollers 238 are successively arranged to contact different sides of the linear substrate 206, thereby avoiding diminished exposure of a particular side of the linear substrate 206 to the liquid infusion solution 208.

[00104] In embodiments, surfaces of the one or more tank rollers 238 and the one or more linear substrate guides 210 include hydrophobic coatings or may be made from a hyrdrophobic material. For example, in embodiments, the first and second concave surfaces 256 and 258 of each of the one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232 have a hydrophobic coating disposed thereon. Such hydrophobic coatings beneficially enable dyes or other active molecules of the liquid infusion solution 208 to contact all sides of the linear substrate 206 when the linear substrate 206 is immersed in the liquid infusion solution 208, even those portions of the linear substrate 206 that are in contact with the one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232. Optionally, a hydrophobic coating or material of the guides serves to provide accumulation of dye on the guide and prevent retention of infusion agent such that movement from one tank to another does not create any appreciable cross contamination of the tank or unwanted color to the linear substrate. The hydrophobic coatings or material may beneficially result in more uniform infusion throughout an entirety of the length of the linear substrate 206. In embodiments, the one or more tank rollers 238 also include such hydrophobic coatings.

[00105] FIG. 3 schematically depicts an infusion tank system 300 that may be used in place in the infusion tank 40 of the infusion system described herein with respect to FIGS. 1A, IB, and 1C. As shown, the infusion tank system 300 includes a first immersion system 302 and a second immersion system 304 that are arranged in series with one another along the feed direction 212. The first immersion system 302 includes a first immersion unit 306 and the second immersion system 304 comprises a second immersion unit 308. In embodiments, the first and second immersion units 306 and 308 are similar in structure to the immersion unit 218 described herein with respect to FIGS. 2A, 2B, 2C, and 2D, and include a one or more movable linear substrate guides 222, 224, 226, 228, 230, and 232 supported by a one or more individually extendable or movable linear substrate guide supports 220. As depicted in FIG. 3, the first and second immersion units 306 and 308 are aligned within one another in the feed direction 212 such that the linear substrate 206 may be manipulated by the first and second immersion units 306 and 308 in sequence. While the depicted embodiment includes two immersion systems 300 and 302, it should be understood that embodiments including only one immersion system (e.g., only the first immersion system 302 or the second immersion system 304) or 3 or more immersion systems are contemplated and within the scope of the present disclosure.

[00106] The first immersion system 302 comprises a first one or more immersion reservoirs 310, 312, 314, and 316 that are disposed on a first conveyor 317. The second immersion system 304 comprises a second one or more immersion reservoirs 318, 320, 322, and 324 that are disposed on a second conveyor 326. The first and second conveyors 317 and 326 comprise a suitable drive mechanism to facilitate conveying the immersion reservoirs disposed thereon in a direction that differs from the feed direction 212 (e.g. in the X-direction depicted in FIG. 3). In embodiments, for example, the first and second conveyers 317 and 326 comprise drive belts upon which the immersion reservoirs are disposed such that the particular immersion reservoir positioned to receive the linear substrate 206 may be adjusted in real-time. While the first and second conveyors 317 and 326 are depicted as singular components, it should be understood that alternative embodiments, where the first and second conveyors 317 and 326 comprise a one or more conveyors for each of the immersion reservoirs of the first and second infusion systems 302 and 304, are also contemplated and within the scope of the present disclosure.

[00107] In embodiments, the first one or more immersion reservoirs 310, 312, 314, and 316 each contain different liquid infusion solutions (e.g., dyes or pigments associated with different colors). While the linear substrate 206 is not immersed in any of the first one or more immersion reservoirs 310, 312, 314, and 316 (e.g., when in a state similar to that depicted in FIG. 2A), the positioning of the first one or more immersion reservoirs 310, 312, 314, and 316 may be adjusted to swap out the liquid infusion solution that the linear substrate 206 is immersed in. As an example, different longitudinal segments of the linear substrate 206 may be colored differently without having to empty any of the first one or more immersion reservoirs 310, 312, 314, and 316, beneficially saving time and avoiding having to stop production or uncoiling of the linear substrate 206. The second one or more immersion reservoirs 318, 320, 322, and 324 may contain a second one or more liquid infusion solutions. In embodiments, for example, the second one or more immersion reservoirs 318, 320, 322, and 324 may contain dyes or pigments that are combined with the dyes or pigments contained in the first one or more immersion reservoirs 310, 312, 314, and 316 to provide more robust coloration schemes. By adjusting the first and second conveyors 317 and 316, the coloration scheme may be altered relatively quickly without having to avoid feeding the linear substrate 206 (e.g., without having to stop operation of an extruder), thereby avoiding costs associated with production stoppages. The first and second immersion systems 302 and 304 may be used to impart any combination of properties on the linear substrate 206. For example, in embodiments, the first immersion system 302 may be used to impart a coloration on the linear substrate 206, while the second immersion system 304 may be used to impart another property (e.g., UV protection, anti-static, or lubricity) on the linear substrate 206. In embodiments, instead of using the conveyors 317 and 326, the immersion units 306 and 308 may be moved to alter the infusion tank in which the linear substrate 206 is immersed.

[00108] It is noted that the terms “substantially” and “about” may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.

[00109] The present description above and in the accompanying drawings are with reference to a variety of examples. The purpose served by the disclosure, however, is to provide examples of the various features and concepts, not to limit the scope of the invention. One skilled in the relevant art will recognize that numerous variations and modifications may be made to the examples described above without departing from the scope of the present invention.

[00110] While particular aspects have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the described subject matter. Moreover, although various aspects have been described herein, such aspects need not be utilized in combination.

[00111] Embodiments can be described with reference to the following clauses, with preferred features laid out in dependent clauses:

[00112] 1. A method of forming an active agent infused linear material comprising: flowing a liquid infusion solution comprising one or more active molecules into an infusion tank such that the liquid infusion solution fills the infusion tank to a fill level; conveying a linear substrate in a first direction using a one or more linear substrate guides such that the linear substrate extends over the liquid infusion solution; moving at least one of the one or more linear substrate guides in a second direction into the liquid infusion solution such that the linear substrate is immersed in the liquid infusion solution while the liquid infusion solution is at an infusion temperature to infuse the one or more active molecules into or onto a surface of the linear substrate thereby forming an active agent infused linear material.

[00113] 2. The method of clause 1, wherein: each of the plurality linear substrate guides is attached to one of a one or more linear substrate guide supports of an immersion unit, and each of the one or more linear substrate guide supports comprises a movable portion that is movable in the second direction to effectuate the moving of the at least one of the one or more linear substrate guides in the second direction.

[00114] 3. The method of clause 2, wherein the one or more linear substrate guide supports comprise support arms that are selectively extendable in the second direction.

[00115] 4. The method of clause 3, wherein the moving the at least one of the one or more linear substrate guides in the second direction comprises moving each of the one or more support arms in the second direction such that guiding surfaces of each of the one or more linear substrate guides are the same distance from the fill level in the second direction.

[00116] 5. The method of any of clauses 1-4, further comprising selecting a feed rate at which the linear substrate travels through the infusion tank based one or more of a production rate of the linear substrate and a demand for a linear substrate.

[00117] 6. The method of any of clauses 1-5, wherein the one or more linear substrate guides comprise one or more rollers that contact the linear substrate and rotate as the linear substrate is conveyed in the first direction.

[00118] 7. The method of clause 6, wherein the one or more rollers comprises a concave surface contacting the linear substrate.

[00119] 8. The method of any of clauses 6-7, wherein the one or more rollers comprises a pair of rollers that face one another and define a cavity through which the linear substrate is guided.

[00120] 9. The method of any of clauses 1 -8, wherein the infusion tank comprises one or more tank rollers that guide the linear substrate along a feed path as the linear substrate is conveyed through the liquid infusion solution. [00121] 10. The method of clause 9, wherein the feed path comprises a meandering path where the linear substrate is successively contacted by the one or more linear substrate guides and the one or more tank rollers.

[00122] 11. The method of any of clauses 1-10, wherein: the one or more linear substrate guides are components of a first immersion unit and the infusion tank is a first infusion tank, and the method further comprises: conveying the linear substrate over a second infusion tank containing a second liquid infusion solution; and moving at least one of a one or more linear substrate guides associated with a second immersion unit in the second direction into the second liquid infusion solution such that the linear substrate is immersed in the second liquid infusion solution.

[00123] 12. The method of clause 11 , wherein the first liquid infusion solution comprises a first dye and the second liquid infusion solution comprises a second dye.

[00124] 13. The method of clause 11, wherein one of the first liquid infusion solution and the second liquid infusion solution comprises a dye, and the other one of the first liquid infusion solution and the second liquid infusion solution comprises one or more active molecules that impart one or more of UV protection, anti-static, or lubricity to the linear substrate.

[00125] 14. The method of clause 11, wherein: the first infusion tank is a component of a first immersion system and the second infusion tank is a component of a second immersion system, and the method further comprises swapping out at least one of the first infusion tank and the second infusion tank by placing at least one additional infusion tank beneath at least one of the first immersion unit and the second immersion unit.

[00126] 15. The method of clause 14, wherein the placing at least one additional infusion tank beneath at least one of the first immersion unit and the second immersion unit comprises conveying the additional infusion tank with a conveyor to a position beneath the first immersion unit or the second immersion unit.

[00127] 16. The method of clause 1, wherein the one or more active molecules of the liquid infusion solution impart one or more of UV protection, anti-static, or lubricity to the linear substrate. [00128] 17. The method of clause 1 , wherein the linear substrate comprises at least one polymer selected from the group consisting of a polyamide, a polyester, polyvinylchloride, or polycarbonate.

[00129] 18. The method of clause 17, wherein the infusion temperature is below a glass transition temperature of the polymer.

[00130] 19. The method of clause 17, wherein the infusion temperature is above a glass transition temperature of the polymer.

[00131] 20. The method of clause 18 or clause 19, wherein the infusion temperature is below a melting temperature of the polymer.

[00132] 21. The method of any one of clauses 17-19, wherein the one or more active molecules comprise an unstable dye.

[00133] 22. The method of any one of clauses 17-19, wherein the one or more active molecules comprise an acid dye.

[00134] 23. The method of any one of clauses 1-4, wherein the first direction is substantially parallel to the fill level.

[00135] 24. The method of any one of clauses 23, wherein the second direction is perpendicular to the first direction.

[00136] 25. A method of forming an active agent infused linear material comprising: manipulating a first one or more linear substrate guides to immerse a linear substrate into a first infusion tank containing a first liquid infusion solution heated to a first infusion temperature to infuse a first set of active molecules into or onto a surface of the linear substrate; conveying the linear substrate along a feed direction over a second infusion tank; and manipulating a second one or more linear substrate guides to immerse the linear substrate into a second liquid infusion solution in the second infusion tank heated to a second infusion temperature to infuse a second set of active molecules into or onto the surface of the linear substrate.

[00137] 26. The method of clause 25, wherein the first one or more linear substrate guides are connected to a first immersion unit via a first one or more linear substrate guide supports and the second one or more linear substrate guides are connected to a second immersion unit via a second one or more linear substrate guide supports.

[00138] 27. The method of clause 26, wherein manipulating the first one or more linear substrate guides comprises extending at least one of the first one or more linear substrate guide supports and manipulating the second one or more linear substrate guides comprises extending at least one of the second one or more linear substrate guide supports.

[00139] 28. The method of any of clauses 25-27, wherein the first and second pluralities of linear substrate guides comprise one or more rollers that contact the linear substrate.

[00140] 29. The method of clause 28, wherein each linear substrate guide of the first and second pluralities of linear substrate guides comprises a pair of rollers that face one another to form a cavity through which the linear substrate extends.

[00141] 30. The method of clause 29, wherein each roller in the pair of rollers of each linear substrate guide comprises a concave surface that contacts the linear substrate.

[00142] 31. The method of clause 28, wherein the first infusion tank and the second infusion tank comprise one or more tank rollers that are disposed between the linear substrate guides of the first and second pluralities of linear substrate guides.

[00143] 32. The method of clause 31, wherein: the linear substrate guides of the first and second pluralities of linear substrate guides are manipulated such that the linear substrate guides are immersed by at least a first distance beneath fill levels of the first and second liquid infusion solutions in the first and second infusion tanks; and the one or more tank rollers of the first and second infusion tanks are positioned beneath the fill levels by less than the first distance.

[00144] 33. The method of clause 25, wherein: the first infusion tank is a component of a first immersion system and the second infusion tank is a component of a second immersion system, and the method further comprises swapping out at least one of the first infusion tank and the second infusion tank by placing at least one additional infusion tank beneath at least one of the first immersion unit and the second immersion unit. [00145] 34. The method of clause 33, wherein the placing at least one additional infusion tank beneath at least one of the first immersion unit and the second immersion unit comprises conveying the additional infusion tank with a conveyor to a position beneath the first immersion unit or the second immersion unit.

[00146] 35. The method of clause 34, wherein: the first immersion system comprises a first one or more infusion tanks disposed on a first conveyor and the second immersion system comprises a second one or more infusion tanks disposed on a second conveyor, and the swapping out at least one of the first infusion tank and the second infusion tank comprises: actuating the first conveyor to place a third infusion tank containing a third liquid infusion solution beneath the linear substrate, and actuating the second conveyor to place a fourth infusion tank containing a fourth liquid infusion solution beneath the linear substrate.

[00147] 36. The method of clause 35, wherein the first and second immersion systems are aligned with one another along the feed direction.

[00148] 37. A linear substrate infusion system comprising: a first infusion tank comprising an open end for receiving a linear substrate; and an immersion unit disposed in alignment with the open end, the immersion unit comprising a one or more movable linear substrate guides attached to the immersion unit via a one or more linear substrate guide supports such that the one or more movable linear substrate guides are independently movable towards the open end to be selectively inserted into the first infusion tank and removed from the first infusion tank.

[00149] 38. The linear substrate infusion system of clause 37, further comprising first and second linear substrate guides disposed proximate to ends of the first infusion tank, the first and second linear substrate guides being configured to receive the linear substrate and guide the linear substrate over the first infusion tank along a feed direction when the immersion unit is in a first operational state.

[00150] 39. The linear substrate infusion system of clause 38, wherein the first and second linear substrate guides are disposed at the same height as the one or more movable linear substrate guides when the immersion unit is in the first operational state. [00151] 40. The linear substrate infusion system of any of clauses 38-39, wherein: the immersion unit comprises a one or more actuators coupled to the one or more linear substrate guide supports, and one or more of the one or more actuators is actuated to extend a portion of the one or more linear substrate guide supports in a direction that is different than the first direction to insert a portion of the one or more movable linear substrate guides into the first infusion tank and place the immersion unit in a second operating state.

[00152] 41. The linear substrate infusion system of any of clauses 37-40, wherein each of the one or more linear substrate guides comprises at least one roller positioned to contact the linear substrate.

[00153] 42. The linear substrate infusion system of clause 41, wherein each of the one or more linear substrate guides comprises a pair of rollers that face one another to define a cavity through which the linear substrate extends.

[00154] 43. The linear substrate infusion system of clause 42, the rollers of each pair of rollers comprise a concave surface positioned to contact the linear substrate.

[00155] 44. The linear substrate infusion system of any of clauses 37-43, wherein the infusion tank comprises a one or more tank rollers positioned between the movable linear substrate guides of the immersion unit.

[00156] 45. The linear substrate infusion system of clause 37, further comprising an infusion solution supply in fluid communication with the first infusion tank for providing a liquid infusion solution to the infusion tank until the liquid infusion solution reaches a fill level, wherein the linear substrate guide supports are movable so as to immerse the one or more movable linear substrate guides in the liquid infusion solution beneath the fill level by at least a distance.

[00157] 46. The linear substrate infusion system of any of clauses 45, further comprising a conveyor unit and a one or more infusion tanks disposed on the conveyor unit.

[00158] 47. The linear substrate infusion system of clause 46, wherein the conveyor unit is configured to convey the first infusion tank out of alignment with the immersion unit and place a second infusion tank into alignment with the immersion unit. [00159] 48. The linear substrate infusion system of clause 37, further comprising: a second infusion tank disposed downstream of the first infusion tank; and a second immersion unit disposed in alignment with the second infusion tank, wherein the second immersion unit comprises a second one or more independently movable linear substrate guides that are movable into and out of the second infusion tank.

[00160] 49. The linear substrate infusion system of clause 48, further comprising: a first one or more infusion tanks disposed on a first conveyor unit, wherein the first conveyor unit comprises a drive belt configured to selectively move a desired one of the first one or more infusion tanks into alignment with the first immersion unit; and a second one or more infusion tanks disposed on a second conveyor unit, wherein the second conveyor unit comprises a drive belt configured to selectively move a desired one of the second one or more infusion tanks into alignment with the second immersion unit.

[00161] 50. The linear substrate infusion system of clause 49, further comprising a first one or more liquid infusion solutions disposed in the first one or more infusion tanks, wherein the first one or more liquid infusion solutions are different from one another.

[00162] 51. The linear substrate infusion system of any of clauses 49-50, further comprising a second one or more liquid infusion solutions disposed in the second one or more infusion tanks, wherein the second one or more liquid infusion solutions are different from one another.

[00163] It is to be understood that the presently disclosed inventive concepts are not limited in application to the details of construction and/or the arrangement of the components set forth in the previous description or illustrated in the drawings. The presently disclosed inventive concepts are capable of other aspects, or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for purpose of description and should not be regarded as limiting.

[00164] Patents and publications mentioned in the specification are indicative of the levels of those skilled in the art to which the invention pertains. These patents and publications are incorporated herein by reference to the same extent as if each individual application or publication was specifically and individually incorporated herein by reference.

Claims

1. A method of forming an active agent infused linear material comprising: conveying a linear substrate in a first direction using one or more linear substrate guides such that the linear substrate extends over a liquid infusion solution; and moving the linear substrate in a second direction into the liquid infusion solution using at least one of the one or more linear substrate guides such that the linear substrate is immersed in the liquid infusion solution while the liquid infusion solution is at an infusion temperature to infuse the one or more active molecules into or onto a surface of the linear substrate thereby forming an active agent infused linear material.

2. The method of claim 1, wherein the moving the linear substrate in the second direction using at least one of the one or more linear substrate guides comprises extending a linear substrate guide support of an immersion unit attached to the one or more linear substrate guides.

3. The method of claim 2, wherein the immersion unit comprises two or more linear substrate guide supports that are selectively extendable in the second direction.

4. The method of claim 3, wherein the moving the linear substrate in the second direction using at least one of the one or more linear substrate guides comprises extending the two or more of the linear substrate guide supports in the second direction to immerse the two linear substrate guides into the liquid infusion solution.

5. The method of any of claims 1-4, further comprising adjusting a feed rate at which the linear substrate travels through the infusion tank based one or more of a production rate of the linear substrate and a demand for a linear substrate.

6. The method of any of claims 1-4, further comprising adjusting an immersion time that the linear substrate is immersed in the liquid infusion solution by adjusting a configuration of the one or more linear substrate guides.

7. The method of claim 6, wherein the one or more linear substrate guides comprises a first linear substrate guide and one or more additional linear substrate guides that is separated from the first linear substrate guide in the first direction.

8. The method of claim 7, wherein the moving the linear substrate in the second direction using at least one of the one or more linear substrate guides comprises immersing the first linear substrate guide in the liquid infusion solution such that an immersed portion of the linear substrate is immersed in the liquid infusion solution for a first immersion time.

9. The method of claim 8, wherein the adjusting the configuration of the one or more linear substrate guides comprises immersing a subset of the one or more additional linear substrate guides in the liquid infusion solution in addition to the first linear substrate guide such that the immersed portion of the liner substrate is immersed in the liquid infusion solution for a second immersion time that is greater than the first immersion time.

10. The method of claim 9, wherein the adjusting the configuration of the one or more linear substrate guides comprises immersing every linear substrate guide of the one or more linear substrate guides in the liquid infusion solution such that the immersed portion of the linear substrate is immersed in the liquid infusion solution for a third immersion time that is greater than the second immersion time.

11. The method of claim 6, wherein the adjusting the immersion time is performed based on an identity of an active molecule of the one or more active molecules in the liquid infusion solution.

12. The method of claim 6, wherein the adjusting the immersion time is performed responsive to a change in a rate at which the linear substrate is conveyed in the first direction.

13. The method of claim 6, wherein the adjusting the immersion time is performed based on a dimension of an infusion tank in which the liquid infusion solution is disposed.

14. The method of any of claims 1-4, wherein the one or more linear substrate guides comprises one or more rollers that contact the linear substrate and rotate as the linear substrate is conveyed in the first direction.

15. The method of claim 14, wherein the one or more rollers comprises a concave surface contacting the linear substrate.

16. The method of claim 14, wherein the one or more rollers comprises a pair of rollers that face one another and define a cavity through which the linear substrate is guided.

17. The method of any of claims 1-4, wherein the liquid infusion solution is contained in an infusion tank comprising one or more tank rollers that guide the linear substrate along a feed path as the linear substrate is conveyed through the liquid infusion solution.

18. The method of claim 17, wherein the feed path comprises a meandering path where the linear substrate is successively contacted by the one or more linear substrate guides and the one or more tank rollers.

19. The method of any of claims 1-4, wherein: the one or more linear substrate guides are components of a first immersion unit; and the method further comprises: conveying the linear substrate over a second liquid infusion solution; and moving a linear substrate guide of a second immersion unit in the second direction into the second liquid infusion solution such that the linear substrate is immersed in the second liquid infusion solution.

20. The method of claim 19, wherein the first liquid infusion solution comprises a first dye and the second liquid infusion solution comprises a second dye.

21. The method of claim 19, wherein one of the first liquid infusion solution and the second liquid infusion solution comprises a dye, and the other one of the first liquid infusion solution and the second liquid infusion solution comprises one or more active molecules that impart one or more of UV protection, anti-static, or lubricity to the linear substrate.

22. The method of claim 19, wherein: the first liquid infusion solution is disposed in a first infusion tank and the second infusion solution is disposed in a second infusion tank; and the method further comprises swapping out at least one of the first infusion tank and the second infusion tank by placing at least one additional infusion tank beneath at least one of the first immersion unit and the second immersion unit.

23. The method of claim 22, wherein the placing at least one additional infusion tank beneath at least one of the first immersion unit and the second immersion unit comprises conveying the additional infusion tank with a conveyor to a position beneath the first immersion unit or the second immersion unit.

24. The method of claim 1, wherein the one or more active molecules of the liquid infusion solution impart one or more of UV protection, anti-static, or lubricity to the linear substrate.

25. The method of claim 1, wherein the linear substrate comprises at least one polymer selected from the group consisting of a polyamide, a polyester, polyethylene, polyvinylchloride, or polycarbonate.

26. The method of claim 25, wherein the infusion temperature is below a glass transition temperature of the polymer.

27. The method of claim 25, wherein the infusion temperature is above a glass transition temperature of the polymer.

28. The method of claim 26, wherein the infusion temperature is below a melting temperature of the polymer.

29. The method of claim 25, wherein the one or more active molecules comprise an unstable dye.

30. The method of claim 25, wherein the one or more active molecules comprise an acid dye.

31. The method of any one of claims 1 -4, wherein the first direction is substantially parallel to the fill level.

32. The method of claim 31, wherein the second direction is perpendicular to the first direction.

33. A method of forming an active agent infused linear material comprising: manipulating one or more linear substrate guides to immerse a linear substrate into a first infusion tank containing a first liquid infusion solution heated to a first infusion temperature to infuse a first set of active molecules into or onto a surface of the linear substrate; moving at least one of the first infusion tank or the one or more linear substrate guides; and manipulating the one or more linear substrate guides to immerse the linear substrate into a second liquid infusion solution in a second infusion tank heated to a second infusion temperature to infuse a second set of active molecules into or onto the surface of the linear substrate.

34. The method of claim 33, wherein the one or more linear substrate guides are connected to a first immersion unit via one or more linear substrate guide supports.

35. The method of claim 34, wherein manipulating the one or more linear substrate guides comprises extending at least one of the one or more linear substrate guide supports.

36. The method of one any of claims 33-35, wherein the one or more linear substrate guides comprise one or more rollers that contact the linear substrate.

37. The method of claim 36, wherein each linear substrate guide of the first and second pluralities of linear substrate guides comprises a pair of rollers that face one another to form a cavity through which the linear substrate extends.

38. The method of claim 37, wherein each roller in the pair of rollers of each linear substrate guide comprises a concave surface that contacts the linear substrate.

39. The method of claim 36, wherein the first infusion tank and the second infusion tank comprise one or more tank rollers that are offset from the one or more linear substrate guides.

40. The method of claim 39, wherein: the one or more linear substrate guides are manipulated such that the one or more linear substrate guides are immersed by at least a first distance beneath fill levels of the first and second liquid infusion solutions in the first and second infusion tanks; and the one or more tank rollers of the first and second infusion tanks are positioned beneath the fill levels by less than the first distance.

41. The method of claim 33, wherein the moving at least one of the first infusion tank or the one or more linear substrate guides comprises conveying the first and second infusion tanks with a conveyor to position the second infusion tank beneath the one or more linear substrate guides.

42. The method of claim 33, wherein: the first infusion tank and the second infusion tank are components of a first immersion system; and the method further comprises conveying the linear substrate into a second immersion system comprising a third infusion tank containing a third liquid infusion solution.

43. The method of claim 42, further comprising swapping out the third infusion tank with a fourth infusion tank of the second immersion system.

44. The method of claim 43, wherein: the first immersion system comprises a first plurality of infusion tanks disposed on a first conveyor and the second immersion system comprises a second plurality of infusion tanks disposed on a second conveyor; and the swapping out the third infusion tank with the fourth infusion tank comprises actuating the second conveyor to place the fourth infusion tank beneath the linear substrate.

45. The method of claim 44, wherein the first and second immersion systems are aligned with one another along the feed direction.

46. A linear substrate infusion system comprising: a first infusion tank comprising an open side for receiving a linear substrate; and an immersion unit disposed in alignment with the open side, the immersion unit comprising one or more movable linear substrate guides attached to the immersion unit via one or more linear substrate guide supports such that the one or more movable linear substrate guides are independently movable towards the open end to be selectively inserted into the first infusion tank and removed from the first infusion tank.

47. The linear substrate infusion system of claim 46, further comprising first and second linear substrate guides disposed proximate to ends of the first infusion tank, the first and second linear substrate guides being configured to receive the linear substrate and guide the linear substrate over the first infusion tank along a feed direction when the immersion unit is in a first operational state.

48. The linear substrate infusion system of claim 47, wherein the first and second linear substrate guides are disposed at the same height as the one or more movable linear substrate guides when the immersion unit is in the first operational state.

49. The linear substrate infusion system of claim 47, wherein: the immersion unit comprises one or more actuators coupled to the one or more linear substrate guide supports; and an actuator of one or more actuators is actuated to extend a linear substrate guide support of the one or more linear substrate guide supports to insert a linear substrate guide of the one or more movable linear substrate guides into the first infusion tank and place the immersion unit in a second operating state.

50. The linear substrate infusion system of any one of claims 46-49, wherein each of the one or more linear substrate guides comprises at least one roller positioned to contact the linear substrate.

51. The linear substrate infusion system of claim 50, wherein each of the one or more linear substrate guides comprises a pair of rollers that face one another to define a cavity through which the linear substrate extends.

52. The linear substrate infusion system of claim 51 , the rollers of each pair of rollers comprise a concave surface positioned to contact the linear substrate.

53. The linear substrate infusion system of any one of claims 46-49, wherein the infusion tank comprises a one or more tank rollers positioned between the movable linear substrate guides of the immersion unit.

54. The linear substrate infusion system of claim 46, further comprising an infusion solution supply in fluid communication with the first infusion tank for circulating a liquid infusion solution through the infusion tank such that the liquid infusion solution fills the first infusion tank to a fill level, wherein the linear substrate guide supports are movable so as to immerse the one or more movable linear substrate guides in the liquid infusion solution beneath the fill level by at least a distance.

55. The linear substrate infusion system of any of claims 54, further comprising a conveyor unit and a one or more infusion tanks disposed on the conveyor unit.

56. The linear substrate infusion system of claim 55, wherein the conveyor unit is configured to convey the first infusion tank out of alignment with the immersion unit and place a second infusion tank into alignment with the immersion unit.

57. The linear substrate infusion system of claim 56, further comprising: a second infusion tank disposed downstream of the first infusion tank; and a second immersion unit disposed in alignment with the second infusion tank, wherein the second immersion unit comprises one or more independently movable linear substrate guides that are movable into and out of the second infusion tank.

58. The linear substrate infusion system of claim 57, further comprising: a first plurality of infusion tanks disposed on a first conveyor unit, wherein the first conveyor unit comprises a drive belt configured to selectively move a desired one of the first plurality of infusion tanks into alignment with the first immersion unit; and a second plurality of infusion tanks disposed on a second conveyor unit, wherein the second conveyor unit comprises a drive belt configured to selectively move a desired one of the second plurality of infusion tanks into alignment with the second immersion unit.

59. The linear substrate infusion system of claim 58, further comprising a first plurality of liquid infusion solutions disposed in the first plurality of infusion tanks, wherein the first plurality of liquid infusion solutions are different from one another.

60. The linear substrate infusion system of any one of claims 48, 49, and 54-59, further comprising a second plurality of liquid infusion solutions disposed in the second plurality of infusion tanks, wherein the second plurality of liquid infusion solutions are different from one another.