Continuous tube with alternating components for medical devices

Abstract

A continuous tube having alternating components along the length of the tube may include at least a first section extruded from a first component along the length of the tube, and at least a second section extruded from a second component along the length of the tube, where the first section and the second section are integrally bonded. Additional sections may be added to the continuous pipe. Such tubing may be used as a medical device, such as an infusion kit.

Description

[0001] This application is a divisional application of the application filed on February 4, 2021, with application number 2021800133054 (international application number PCT / US2021 / 016672) and entitled "Continuous tubular fitting having alternating components for a medical device". Technical Field

[0002] This disclosure generally relates to tubing, and more particularly to continuous tubing having alternating components along its length. Such tubing can be used in medical devices, such as tubing for administering medical fluids via infusion. Background Technology

[0003] Plastic tubing is widely used in the medical field, especially in patient analysis and treatment processes. However, medical tubing requires different, and sometimes incompatible, requirements. For example, medical tubing should be inert and prevent contamination of the fluid it carries. However, many plastic materials with these properties tend to be non-flexible. In many applications, however, medical tubing is clamped or clipped, or used with infusion pumps that move fluid through the tubing by compressing it. This application requires flexible tubing. However, flexible tubing, such as silicone tubing, is difficult to bond to other materials, such as polycarbonate, PMMA, acrylic terpolymers, polyesters, copolyesters, acrylonitrile-butadiene-styrene, and methacrylonitrile-acrylonitrile-butadiene-styrene connectors.

[0004] To address the diverse needs of medical tubing, these fittings are made from multiple layers of different polymer materials to modify their properties. However, fittings made from different materials may suffer from delamination. Mechanical and frictional combinations of flexible fittings have also been used, but these mechanisms have limited low tensile strength, and the fittings can slide through mechanical retaining mechanisms. Therefore, there is a persistent need for medical tubing that can address the diverse needs of medical applications. Summary of the Invention

[0005] This subject matter relates to a continuous pipe having alternating components along its length. Such a continuous pipe may include at least a first segment having a first component along its length and at least a second segment having a second component along its length, wherein the first component differs from the second component. The pipe may further include third, fourth, and so on, having the same or different components. These segments are integrally joined and can be formed by sequentially extruding the first component, then the second component, etc.

[0006] This subject matter also relates to a method for forming a continuous tube having alternating components along its length. The method may include extruding a first segment of the tube along the length of the tube by a first pump on an extrusion line using a first pump, followed by extruding a second segment of the tube along the length of the tube by a second pump on an extrusion line using a second pump. Advantageously, the first and second components are different, and the first and second segments are integrally combined by sequentially extruding the first and second components to form corresponding segments. The method may further include extruding a third segment of the tube along the length of the tube by a third pump on an extrusion line using a third pump, wherein the second and third segments are integrally combined. In some aspects, the method further includes forming transition segments between adjacent segments, for example, between the first and second segments. The transition segments comprise mixtures of the corresponding components forming the adjacent segments.

[0007] The aforementioned embodiments of the continuous pipe fittings and methods individually or in combination include one or more of the following features. In some embodiments, the first component may differ from the second component such that the properties of the first segment and the second segment differ by at least 5%. For example, the first segment and the second segment may have a Shore A hardness level that differs by at least 5% as different properties. This difference in properties can be achieved by making the polymer materials in the first component and the second component different and / or by making the amount or type of additives between the first component and the second component different. For example, the first segment may contain a polyvinyl chloride component with a certain amount of plasticizer, and the second segment may contain a polyvinyl chloride component with a certain amount of plasticizer, wherein the amount of plasticizer in the first segment is less than the amount of plasticizer in the second segment. In other embodiments, the first segment and an optional third segment may have a Shore A hardness of at least about 70, and the second segment may have a Shore A hardness of no more than about 60. In a further embodiment, the first component comprises a first polymer, and the second component comprises a second polymer, wherein the first polymer is different from the second polymer. In other embodiments, the components of the first segment and the optional third segment may comprise non-hydrogenated styrene-based TPE, and the components of the second segment may comprise hydrogenated styrene-based TPE.

[0008] Additional advantages of the present subject matter will readily be apparent to those skilled in the art from the following detailed description, wherein only certain aspects of the present subject matter are shown and described by way of illustration. As will be appreciated, the present subject matter can have other and different constructions, and certain details thereof can be modified in various other ways without departing from the present subject matter. Therefore, the accompanying drawings and description are to be considered illustrative in nature, rather than limiting. Attached Figure Description

[0009] The accompanying drawings are included to provide a further understanding and are incorporated in and form part of this specification. The drawings illustrate the disclosed embodiments and, together with the description, serve to explain the principles of the disclosed embodiments. In the drawings:

[0010] Figure 1 An exemplary continuous tube with alternating components along its length is shown, which is manifested as hard-soft-hard sections along the tube length.

[0011] Figure 2 Another exemplary continuous tube with alternating components along its length is shown, which manifests as hard-soft-hard sections along the tube length. In this example, the outer diameter of the tube gradually decreases at both ends, which helps to determine the position of the ends in the recessed joint of the connector.

[0012] Figure 3 An exemplary continuous tube having alternating components along its length is shown, which is partially inserted into a recess of an exemplary connector.

[0013] Figure 4 Another exemplary continuous tube with alternating components along its length is shown. Detailed Implementation

[0014] The detailed description below depicts various constructions of the subject matter and is not intended to represent the only construction that can be used to practice the subject matter. The detailed description includes specific details to provide a thorough understanding of the subject matter. Therefore, dimensions regarding certain aspects are provided as non-limiting examples. However, it will be clear to those skilled in the art that the subject matter can be practiced without these specific details. In some cases, well-known structures and components are shown in block diagram form to avoid obscuring the concepts of the subject matter.

[0015] It should be understood that this disclosure includes examples of the subject matter and does not limit the scope of the appended claims. Various aspects of the subject matter will now be disclosed based on specific, but not limiting, examples. The various embodiments described in this disclosure can be implemented in different ways and variations and according to the desired application or implementation.

[0016] This subject matter relates to continuous pipe fittings having alternating components along the length of the pipe, and more specifically, to continuous pipes having at least a first segment formed by a first component along the length of the pipe and at least a second segment formed by a second component along the length of the pipe, wherein the first component is different from the second component, thereby forming a continuous pipe with AB segments, where "A" and "B" represent segments formed by different components. Advantageously, the first segment and the second segment are integrally joined together along the length of the pipe, with or without a transition segment.

[0017] In certain aspects of this disclosure, a continuous pipe fitting having alternating first and second sections may further include other sections, for example, a third section integrally joined to the second section along the length of the pipe. The third section may be formed of a third component, such that the first and third sections are made of different materials, thereby forming an ABC-segmented continuous pipe. Alternatively, the first and third sections may be formed of the same component, thereby forming an ABA-segmented continuous pipe. Advantageously, adjacent sections of different components are integrally joined, for example, with or without a transition section, the first and second sections are integrally joined to each other, and the second and third sections are integrally joined to each other.

[0018] In some aspects of this disclosure, segments formed from different components (e.g., a first component and a second component) may have properties differing by at least 5% (e.g., at least 10%), such as hardness, flexibility, and bondability. For example, the hardness of adjacent segments may differ by at least 4 units. Alternatively, adjacent first and second segments may have a Shore A hardness level differing by at least 5%. In some aspects of this disclosure, the first segment of a continuous tubing may be rigid or stiff, while the integrally bonded second segment may be flexible. For example, medical tubing for IV kits having a Shore A hardness of about 85 or higher is considered rigid and is used in certain applications, while tubing for pumping medical fluids typically uses softer tubing with a Shore A hardness of about 60 or less. In some aspects of this disclosure, hard-soft segments may be integrally bonded, wherein the hard segment is formed by the first component and the soft segment is formed by the second component. The first and second components may comprise the same or different polymers. When the same polymer (such as polyvinyl chloride) is included, the first and second components may include different amounts or types of additives, such as lower or higher amounts of plasticizers, thereby forming different components. In other aspects of this disclosure, the first and second segments may have the same or similar hardness levels, but include different polymers.

[0019] The alternating continuous tubing of this disclosure can be manufactured by alternating extrusion of different components on the same extrusion line. For example, an extrusion line having a first extrusion pump supplied with a first component can be started to extrude a first segment of a tube made of the first component, and after a certain length, the first pump can be stopped. Then a second pump supplied with a second component can be started to extrude a second segment of the tubing having the second component for a certain length, and then the second pump can be stopped. This process can be repeated by starting and stopping the first and second pumps with the first and second components respectively to form a tube having alternating first and second segments with the first and second components. The alternating tubing formed by alternating extrusion can be cut within the first or second segment to form a tubing with ABA or BAB segments. Furthermore, additional extrusion pumps supplying different components can also be included on the same extrusion line to form third and fourth segments having a third and fourth component in any order. For example, a tubing manufactured on an alternating polymer extrusion line can have a material transition section in which different components are mixed, and the mixture forms a transition section between the first and second segments. Transition sections can occur when one component pump (e.g., the first pump) stops and another pump (e.g., the second pump) starts, due to a small amount of one component remaining in the dead space between the pump and die exit area on the extrusion line. This material transition section can be minimized by reversing the pump before it stops. Alternatively, or further, transition sections between sections, such as the transition section between the first and second sections, can be minimized by venting the component from the dead space using a valve.

[0020] Therefore, in an aspect of the invention, a method of forming a tube having alternating components along its length includes extruding a first segment of the tube from a first component along the length of the tube using a first pump on an extrusion line, and subsequently extruding a second segment of the tube from a second component along the length of the tube using a second pump on an extrusion line. By sequentially extruding the first and second segments, the first and second segments are integrally joined. The method may further include extruding a third segment of the tube from a third component along the length of the tube using a third pump on an extrusion line to integrally join the second and third segments. The first, second, and third components may be different, and segments may differ by at least 5% (e.g., at least 10%) in properties (e.g., hardness).

[0021] Alternating extrusion techniques for producing tubular fittings with alternating components along the length of the tube advantageously create substantially seamless transitions between segments because these segments are integrally bonded. Therefore, the transitions between segments are as robust as the material components themselves. Furthermore, a further method may include forming transition segments between adjacent segments (e.g., between a first segment and a second segment), wherein the transition segment comprises a mixture of the first and second components. Alternatively, such transition segments can be minimized by reversing the pump associated with a particular segment.

[0022] Selecting slightly miscible components for different sections of a continuous pipe fitting facilitates the integration of components along the pipe and prevents separation of the first section, second section, etc., of the pipe made from such different components. Miscibility calculations based on Hansen solubility parameters and / or literature can guide the selection of suitable miscible materials and their components. Such information can be found, for example, in White, James L. Kim, Kwang-Jea. (2008). Thermoplastic and Rubber Compounds - Technology and Physical Chemistry - 5.4 Miscible Polymer Blends. (pp. 157, 158, 159), Hanser Publishing.

[0023] For example, components that can be sequentially extruded as the first component include styrene-based thermoplastic elastomers (TPE), non-hydrogenated styrene-based TPE, thermoplastic polyurethane ester-based, ether-based, or carbonate-based, thermoplastic olefins (TPO) or combinations thereof, blends of TPO with low-density polyethylene (LDPE) or polypropylene (PP), polyether block amides, copolyester elastomers, polyvinyl chloride (PVC), and any blends thereof. Components that can be sequentially extruded as the second component include, for example, styrene-based TPE, non-hydrogenated and hydrogenated styrene-based TPE and blends thereof, thermoplastic polyurethane ester-based, ether-based, or carbonate-based, EVA, blends of EVA with thermoplastic polyurethane (TPU), blends of polyethylene vinyl acetate (EVA) with LDPE, TPO, PVC, etc., and combinations thereof. TPO, a thermoplastic olefin, includes: propylene-based elastomers, olefin block copolymers, propylene-ethylene copolymers, and ethylene-octane copolymers. Styrene-based TPEs include hydrogenated polyisoprene polymers such as styrene-ethylene-propylene-styrene (SEPS) and styrene-ethylene-propylene (SEP), hydrogenated polybutadiene polymers such as styrene-ethylene-butene-styrene (SEBS), styrene-ethylene-butene (SEB), styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), and styrene-isoprene-butadiene-styrene (SIBS), hydrogenated polyisoprene / butadiene polymers such as styrene-ethylene-ethylene-propylene-styrene (SEEPS), and blends thereof with polyolefins such as polypropylene. The first and second components, and optionally the third component, may include additives, such as plasticizers.

[0024] Figure 1An example of a continuous tube with alternating components along its length, as an ABA segment, is shown. As shown, the continuous tube 100 includes first and third sections (110 and 130, respectively) at opposite ends of the tube 100, and an intermediate section 120. The first and third sections (110 and 130, respectively) can be extruded from the first component and integrally bonded to the intermediate section 120, which can be extruded from the second component. In this example, the end sections (110 and 130) include components that create hard sections, and the intermediate section (120) includes components that form relatively soft sections. For example, the first and third sections may have a Shore A hardness greater than about 85, while the second section may have a Shore A hardness less than about 80. For medical tubing applications, a Shore A hardness greater than about 85 is generally considered hard. Pumping tubing typically uses softer tubing with a Shore A hardness of about 55. Tubing with a Shore A hardness greater than 85 is considered rigid. In this example, end segments 110 and 130 have a relatively shorter length than the middle segment 120; for example, the end segments (110, 130) have a length not exceeding approximately 2 inches (approximately 50.8 mm), for example, between approximately 0.25 inches (6.35 mm) and approximately 1.5 inches (38.1 mm). This ABA-segmented tube can be used to solvent-bond the A segment to a connector, such as a recessed connector comprising a rigid acrylic-based material. In this way, a tube made of a material difficult to solvent-bond (e.g., segment 120) can be solvent-bonded via the end segments (110, 130), which can be made of a material more easily solvent-bonded to connectors.

[0025] Figure 2Another exemplary continuous tube with alternating components along its length is shown, which manifests as hard-soft-hard sections along the tube length. As shown, the continuous tube 200 includes first and third sections (210 and 230, respectively) at opposite ends of the tube 200, and an intermediate section 220. For this example, the end sections (210 and 230) include components that form hard sections, and the intermediate section (220) includes components that form relatively soft sections. The first and third sections (210 and 230, respectively) can be extruded from the first component and integrally bonded to the intermediate section 220, which can be extruded from the second component. For this example, the tube 200 includes a transition section 215 between the first section 210 and the second section 220, which can be formed by the alternating extrusion technique described herein, and a transition section 225 between the second section 220 and the third section 230. The length of the transition sections (215, 225) is less than about 15 mm. Furthermore, the first segment 210 includes a first diameter segment (212) and a reduced (smaller) diameter segment (214), and the third segment 230 includes a first diameter segment (232) and a reduced (smaller) diameter segment (234). The reduced diameter segments (214, 234) can be inserted into recessed joints of connectors (e.g., connectors comprising rigid acrylic-based materials). Additionally, this configuration can be used for visual inspection to ensure that the joint is fully inserted.

[0026] Figure 3 An exemplary continuous tube 200 is shown, wherein a reduced (smaller) diameter segment 214 of a first section is partially inserted into a recess 352 of an exemplary connector 350. If the tube is not fully inserted into the recess of the connector to bond the tube to the connector, or if the tube is forced out of the recess due to, for example, a lack of proper adhesion with a solvent, then a gap (360) is noticeable outside the entrance to the bonding recess. Control measures can be taken to monitor the presence of the gap, and if a gap of a certain predetermined length is found, the joint can be considered defective.

[0027] The continuous pipe fittings disclosed herein, for example in Figure 1-3 The examples illustrated herein can be used as medical fittings for administering medical fluids via infusion (e.g., using intravenous infusion assemblies, gravity containers, and / or infusion pumps) to deliver intravenous fluids to a patient. An assembly of fittings, valves, accessories, and needles that connects a fluid container to a patient via intravenous infusion can be referred to as an "IV kit." An infusion pump is a medical device that can be used to administer intravenous (IV) fluids. Such assemblies, containers, and pumps employ fittings connected to one or more medical connectors; the fittings of this invention are also useful.

[0028] In some respects, continuous pipe fittings may include a first and a third section formed of an acrylic-based TPE blend, a non-hydrogenated styrene thermoplastic elastomer, a thermoplastic polyurethane, or PVC, such as the end section of an ABA pipe, and a second section, such as an intermediate section, formed of a hydrogenated styrene thermoplastic elastomer, a blend of hydrogenated styrene thermoplastic elastomer and PP, a blend of hydrogenated and non-hydrogenated styrene thermoplastic elastomers, polyvinyl chloride, thermoplastic polyurethane, or thermoplastic siloxane-polyether-polyurethane.

[0029] Alternating continuous pipe fittings, designed by selecting appropriate materials for various sections (e.g., end sections and intermediate sections), allow for customized fittings with properties unattainable by pipes formed from a single material or even laminated materials. For example, the alternating extrusion technology (AET) described herein allows for... Figure 1-3 The custom design shown.

[0030] In addition, continuous tubing with alternating components along the length of the tube can be used in pump infusion kits. Pump infusion kits typically have tubing mounted on the pump to regulate fluid flow. In some applications, the tubing includes upper and lower fittings attached to opposite ends of the tube. Tubing is typically made of soft polymers, such as silicone, to allow for compression with relatively small forces and to allow the tube to fully spring back once the force is removed. However, silicone tubing is difficult to bond to other materials, such as polycarbonate (PC), acrylonitrile-butadiene-styrene (ABS), acrylic, and other plastics. Due to the difficulty in bonding silicone to other plastics, mechanical / friction bonding devices are typically used to bond silicone to other plastics, such as fittings used with pumps. However, these bonding devices typically produce a small pull force (approximately 3 lbf), the force required to break a silicone tube bonded to another plastic. This is because, firstly, there is no intermolecular bonding, and secondly, because silicone is a relatively soft material, it is easily deformed.

[0031] However, a continuous tube with alternating components along its length according to this disclosure can replace conventional silicone tubing that is bonded to other plastics by mechanical / friction devices. Therefore, a continuous tube with alternating components along its length according to this disclosure can advantageously minimize the components required to bond the tubing to other devices.

[0032] Figure 4An example of a continuous tube having alternating hard-soft-hard sections is shown. As shown, tube 400 has first and third sections (410, 430, respectively) at opposite ends of the tube, and an intermediate section (420). For this example, the section sections (410 and 430) include components that produce hard sections (e.g., having a Shore A hardness of at least about 70 A, such as from about 70 A to about 85 A), and the intermediate section (420) includes components that form soft sections (e.g., having a Shore A hardness of no more than about 60 A, such as between about 55 A and 50 A). Such a continuous tube can be formed by extruding alternating first and second components and cutting such a formed tube within a first section formed by the first component. Furthermore, a tube having hard-soft-hard sections can be formed from a first component comprising a hard PVC polymer component integrally bonded to the intermediate section by sequential extrusion, the intermediate section being formed from a softer PVC component with a hardness of about 50 A to about 55 A. The rigid PVC polymer component used in the first section can contain less plasticizer than the softer PVC polymer component used in the second section. The middle sections of the rigid-soft-rigid segmented tube can match the softness of silicone while having rigid end sections that can be used for bonding to fittings.

[0033] Furthermore, the transitions between sections can be seamless, making the bonded hard-soft-hard sections a single unit, as robust as the material composition of the sections themselves. The end sections of this integrally formed hard-soft-hard tube can be joined to the upper and lower fitting components (422 and 432, respectively) by solvent bonding rather than mechanical bonding fittings. Therefore, the tensile strength is expected to be significantly higher than with silicone mechanical bonding (approximately 15 lbf or higher).

[0034] Furthermore, continuous tubing with alternating components along its length can be used as medical devices, such as catheter fittings. Some conventional catheter fittings use silicone, with a lubricating coating applied to one end after the silicone tubing is formed through a secondary processing. This lubricating coating is desirable because it facilitates insertion of the silicone catheter into delicate mucosal tissue. However, issues can arise regarding the control of the lubricant or coating amount, uniform coverage on the fitting, and reduced effectiveness due to shearing during insertion, the cost and complexity of the secondary processing of applying the lubricating coating to the catheter. Advantageously, the method described in this disclosure can manufacture catheter fittings having a first segment formed from a lubricating material composed of one or more polymers and lubricating additives, including, for example, thermoplastic polyurethane, PVC, and polyether block amides. This polymer can be formulated with lubricating additives such as EveGlide, Mobilize, PEBASlide, ProPellS, etc. The second segment can be made from a second component material commonly used in catheters, such as thermoplastic polyurethane (TPU), PVC, polyether block amides, or combinations thereof.

[0035] It should be understood that any particular order or hierarchy of the boxes in the disclosed process is illustrative of the example method. Based on design or implementation preferences, it should be understood that a particular order or hierarchy of the boxes in the process may be rearranged, or all shown boxes may be executed. In some implementations, any boxes may be executed simultaneously.

[0036] This disclosure is provided to enable any person skilled in the art to practice the various aspects described herein. This disclosure provides various examples of the subject matter, and the subject matter is not limited to these examples. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects.

[0037] Unless otherwise specified, elements involving the singular form are not intended to mean "one and only one," but rather "one or more." Unless otherwise specified, the term "some" refers to one or more. Masculine pronouns (such as his) include feminine and neuter pronouns (such as her and its), and vice versa. Titles and subtitles, if any, are used for convenience only and do not limit the invention.

[0038] The word “exemplary” is used herein to mean “serving as an example or illustration.” Any aspect or design described herein as “exemplary” is not necessarily to be construed as being superior or more advantageous than other aspects or designs. In one respect, the various alternative constructions and operations described herein may be considered at least equivalent.

[0039] As used herein, the phrase "at least one" preceding a series of items, separated by the term "or," modifies the listed items as a whole, not each item individually. The phrase "at least one" does not require the selection of at least one item; rather, it allows for the inclusion of at least one of any one item, and / or at least one of any combination of items, and / or at least one of each item. For example, the phrase "at least one of A, B, or C" could refer to: only A, only B, or only C; or any combination of A, B, and C.

[0040] A phrase, such as "aspect," does not imply that such an aspect is essential to the art, or that such an aspect applies to all constructions of the art. Disclosure relating to an aspect may apply to all constructions, or one or more constructions. An aspect may provide one or more examples. A phrase, such as "aspect," may refer to one or more aspects, and vice versa. A phrase, such as "embodiment," does not imply that such an embodiment is essential to the art, or that such an embodiment applies to all constructions of the art. Disclosure relating to an embodiment may apply to all embodiments, or one or more embodiments. An embodiment may provide one or more examples. A phrase referring to such an embodiment may refer to one or more embodiments, and vice versa. A phrase, such as "construction," does not imply that such a construction is essential to the art, or that such a construction applies to all constructions of the art. Disclosure relating to a construction may apply to all constructions, or one or more constructions. A construction may provide one or more examples. Such a construction may refer to one or more constructions, and vice versa.

[0041] In one respect, unless otherwise stated, all measurements, numerical values, ratings, positions, sizes, dimensions, and other specifications set forth in this specification, including in the following claims, are approximate, not precise. In another respect, they are intended to have a reasonable range that is consistent with the functions they address and with the conventions of the field to which they belong.

[0042] It should be understood that the specific order or hierarchy of the disclosed steps, operations, or processes is an illustration of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps, operations, or processes can be rearranged. Some steps, operations, or processes can be performed simultaneously. Some or all steps, operations, or processes can be performed automatically without user intervention. The appended method claims (if any) present elements of various steps, operations, or processes in an exemplary order and are not intended to limit one to the specific order or hierarchy presented.

[0043] All structural and functional equivalents of elements throughout the various aspects described in this disclosure, known or to be known by one of ordinary skill in the art, are expressly incorporated herein by reference and are intended to be covered by the claims. Furthermore, regardless of whether such disclosure is expressly stated in the claims, the contents of this disclosure are not intended for public use. No element of a claim is construed under 35 USC §112(f) unless the phrase “means for…” is used to expressly state an element of the claim, or, in the case of a method claim, the phrase “steps for…” is used to state an element of the claim. Furthermore, with regard to the scope of terms such as “comprising,” “having,” etc., such terms are intended to refer to openness in a manner similar to the term “including,” as interpreted when “comprising” is used as a transitional word in a claim.

[0044] The title, background, overview, drawings, brief description, and abstract of this disclosure are incorporated herein by reference and are provided as illustrative examples rather than as limiting descriptions. It should be understood upon filing this application that they are not intended to limit the scope or meaning of the claims. Furthermore, as will be apparent from the detailed description, which provides illustrative examples, various features are combined in various embodiments for the purpose of simplification. The methods of this disclosure should not be construed as reflecting an intention that the claimed subject matter requires more features than expressly stated in each claim. Rather, as reflected in the following claims, the subject matter of the invention lies in fewer than all features of a single disclosed construction or operation. The following claims are thus incorporated into the detailed description, each claim being an independent, separately claimed subject matter.

[0045] The claims are not intended to be limited to the aspects described herein, but rather to conform to the full scope consistent with the language claims and to cover all legal equivalents. Nevertheless, none of the claims are intended to include subject matter that fails to meet the requirements of 35 U.S.SC § 101, 102, or 103, nor should they be interpreted in this manner.

Claims

1. A continuous tube having alternating components along its length, the tube comprising at least a first segment having a first polymer component along its length, at least a second segment having a second polymer component along its length, and at least a third segment having a third polymer component along its length. in, In the absence of a transition section between the first section and the second section, the first section is integrally joined to the second section along the length of the pipe. Where there is no transition section between the second and third sections, the at least third section is integrally incorporated into the second section. The first segment and the third segment are joined to the second segment at their opposite ends. Wherein, the first polymer component comprises a first polymer, and the second polymer component comprises a second polymer different from the first polymer; and The first and third segments each have a higher Shore A hardness level than the second segment.

2. The continuous tube according to claim 1, wherein, The first segment and the second segment have a Shore A hardness level that differs by at least 5%.

3. The continuous tube according to claim 1, wherein, The first segment contains a polyvinyl chloride component with a certain amount of plasticizer, and the second segment contains a polyvinyl chloride component with a certain amount of plasticizer, wherein the amount of plasticizer in the first segment is less than the amount of plasticizer in the second segment.

4. The continuous tube according to claim 1, wherein, The first and third segments have substantially the same polymer composition.

5. The continuous tube according to claim 4, wherein, The components of the first and third segments comprise non-hydrogenated styrene-based thermoplastic elastomers (TPEs), and the components of the second segment comprise hydrogenated styrene TPEs.

6. The continuous tube according to claim 4, wherein, The first and third segments have a Shore A hardness of at least 70, and the second segment has a Shore A hardness of no more than 60.

7. The continuous tube according to claim 1, wherein, The first polymer component comprises a lubricating polymer formed from thermoplastic polyurethane (TPU), polyvinyl chloride (PVC), polyether block amide or a combination thereof, and lubricating additives, and the second polymer component comprises thermoplastic polyurethane (TPU), polyvinyl chloride (PVC), polyether block amide or a combination thereof.

8. The continuous tube according to claim 1, wherein, The first component includes styrene-based thermoplastic elastomers (TPE), non-hydrogenated styrene-based TPE, thermoplastic polyurethane ester-based, ether-based or carbonate-based, thermoplastic olefins (TPO), or combinations thereof.

9. The continuous tube according to claim 1, wherein, The second component includes styrene-based TPE, unhydrogenated and hydrogenated styrene-based TPE and blends thereof, thermoplastic polyurethane ester-based, ether-based or carbonate-based, vinyl acetate (EVA), blends of EVA and thermoplastic polyurethane (TPU), blends of vinyl acetate (EVA) and low-density polyethylene (LDPE), TPO, polyvinyl chloride (PVC), and combinations thereof.

10. A method of forming a continuous tube having alternating components along its length, the method comprising: On the extrusion line, a first section of the tube is extruded by a first pump along the length of the tube from a first polymer component, and then a second section of the tube is extruded by a second pump along the length of the tube from a second polymer component on the extrusion line. On the extrusion production line, the third section of the tube is extruded by the third polymer component along the length of the tube using the third pump. Where there is no transition section between the first segment and the second segment, the first segment and the second segment are integrally combined. Where there is no transition section between the second and third sections, the second and third sections are integrally combined. The first segment and the third segment are joined to the second segment at their opposite ends. The first and third segments each have a higher Shore A hardness level than the second segment. Wherein, the first polymer component includes a first polymer, and the second component includes a second polymer that is different from the first polymer.

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