Double-layer tubing for IV fluid sets

Abstract

The continuous tube has an inner layer containing a polyethylene composition and an outer layer containing a thermoplastic elastomer, and the inner and outer layers are arranged concentrically without a bonding layer between them. The method for manufacturing the continuous tube includes co-extrusion molding of the polyethylene composition and the thermoplastic elastomer resin without providing an adhesive or bonding layer.

Description

Technical Field

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 455,207, filed on March 28, 2023, "DOUBLE LAYER TUBING FOR IV INFUSION SETS", under 35 U.S.C. § 119, and the entire contents thereof are incorporated herein by reference.

[0002] The present invention relates to the field of drug administration. More specifically, the present invention relates to a multi-layer infusion tube used for drug administration.

Background Art

[0003] Tubing lines used for drug administration to patients (e.g., via intravenous infusion) are often required to meet stringent limitations regarding drug adsorption and performance requirements such as bend resistance, transparency, surface feel, etc.

[0004] Conventional infusion (fluid infusion) tubes are formed of polyvinyl chloride with a polyethylene liner (PVC with a PE lining), and typically require a bonding layer (tie layer) such as ethylene vinyl acetate copolymer to bond the non-polar PE to the polar PVC, thereby preventing delamination. In such a system, there are several disadvantages to using an EVA-based bonding layer adhesive. One of the main disadvantages is that EVA emits an odor when extruded at high temperatures. The EVA resin is known to have low low-temperature stability. Furthermore, the EVA resin degrades at high processing temperatures, contaminates the extrusion system, and generates gels and black spots in the laminate.

Summary of the Invention

[0005] The technology disclosed in this invention can, advantageously, provide an improved PVC-free infusion tube, eliminating the regulatory and environmental risks associated with the use of PVC and plasticizers in infusion tubes for drug administration. Further advantageously, the tubes disclosed in this invention exhibit low drug adsorption, meeting the labeling requirements described in the instructions for use of certain drugs relating to PE line infusion tubes. In addition, the coated PE material improves the peel resistance of the tube as a pumping tube segment by reducing friction on the inner surface of the TPE.

[0006] While TPE does not contain low-molecular-weight plasticizers like those found in PVC, it may still contain oils, lubricants, and other small amounts of additives, which can leach into the fluid injected through the tube. Advantageously, by eliminating PVC and coating with PE, the leaching of chemicals from the TPE into the administered drug solution is prevented.

[0007] The method disclosed in this invention advantageously and significantly simplifies the extrusion process by eliminating the need for a bonding layer due to the compatibility between PE and TPE. Furthermore, the disclosed method provides an inexpensive technique for providing an injectable tube that maintains performance indicators such as flexural resistance and surface feel while eliminating potential drug loss due to adsorption or absorption of drugs on the inner surface of the injectable tube. While specific use cases include the medical industry, these solutions have broad applicability in other industrial fields as well.

[0008] In one embodiment, the continuous tube has an inner layer containing polyethylene and an outer layer containing a thermoplastic elastomer. The inner and outer layers are arranged concentrically without an intermediate layer between them.

[0009] In another embodiment, the infusion set includes a disclosed continuous tube connected to a medical connector.

[0010] In another embodiment, a method for preparing a continuous tube includes co-extruding a polyethylene composition together with a thermoplastic elastomer resin without providing an adhesive or binding layer between them.

[0011] Additional features and advantages of this technology are described in detail below, some of which may become apparent from the description or may be understood through the implementation of this technology. The advantages of this technology are realized and achieved by the description and examples of the present invention and the configurations particularly shown in the accompanying drawings.

[0012] Please understand that the above general description and the following detailed description are for illustrative and explanatory purposes only, and are intended to further explain this technology. [Brief explanation of the drawing]

[0013] Various features of at least some embodiments of this disclosure are described below with reference to the drawings. The illustrated embodiments are not intended to limit the invention but are intended to illustrate it. The drawings include the following figures. [Figure 1] This is a schematic cross-sectional view of a tube according to at least some embodiments of the present disclosure. [Figure 2A] This is a cross-sectional view of an example of a tube according to at least some embodiments of the present disclosure. [Figure 2B] This is a cross-sectional view of an example of a tube according to at least some embodiments of the present disclosure. [Figure 3A] This is an image of one type of blue-colored PVC tube with a conventional bonding layer and a PE liner, after a predetermined number of operation-non-operation cycles using a pinch clamp. [Figure 3B] This image shows another type of blue-tinted PVC tube with a conventional bonding layer and a PE liner, after a predetermined number of operation-non-operation cycles using a pinch clamp. [Figure 4A] This is an image of one type of TPE tube with a PE liner after the same number of operation-non-operation cycles as in Figure 3A using a pinch clamp. [Figure 4B] These are images of other types of TPE tubing with PE liners after the same number of operation-non-operation cycles as in Figure 3B using a pinch clamp. [Figure 5A] This is an image of one type of blue-colored PVC tube with a PE liner having a bonding layer, after a predetermined number of operation-non-operation cycles using a roller clamp. [Figure 5B] This is an image of another type of blue-tinted PVC tube with a PE liner and a bonding layer, after a predetermined number of operation-non-operation cycles using a roller clamp. [Figure 6A] This image shows a TPE tube with a PE liner after the same number of operation-non-operation cycles as in Figure 5A, using a roller clamp. [Figure 6B] This image shows a TPE tube with a PE liner after the same number of operation-non-operation cycles as in Figure 5B, using a roller clamp. [Figure 7] Figures 3A-3B show two types of blue-colored PVC tubes with PE liners having a bonding layer, and Figures 4A-4B show two types of TPE tubes with PE liners, comparing the results of a blade scratch test. [Modes for carrying out the invention]

[0014] Various configurations of this technology will be readily apparent to those skilled in the art from the disclosure of the present invention. These various configurations are shown and described as examples. As should be understood, this technology may take other different configurations, and some of its details can be modified in various ways without departing from the scope of this technology. Therefore, the abstract, drawings, and detailed description are essentially illustrative and should not be construed as limiting.

[0015] The detailed description below is intended to describe various configurations of the present technology and does not represent the only configuration in which the technology can be implemented. The accompanying drawings are incorporated into the present invention and constitute part of the detailed description. The detailed description includes certain details for the purpose of making the technology fully understandable. However, it will be apparent to those skilled in the art that the technology can be implemented without these specific details. In some cases, known structures and components are shown in block diagram form so as not to obscure the concepts of the technology. Identical components are shown with the same element number for ease of understanding.

[0016] Traditionally, tubes used for intravenous drug administration have been made of polyvinyl chloride (PVC), with their inner surface lined with a non-polar polymer material to prevent interaction between the PVC and drug molecules. Polyethylene (PE) is the most commonly used non-polar polymer for lining PVC tubes, but PE generally does not have good adhesion properties to PVC. Therefore, to prevent delamination, a bonding layer is used to adhere the non-polar PE material to the PVC tube.

[0017] One example of a material used for the binder layer is ethylene vinyl acetate copolymer (EVA). However, EVA has several drawbacks when used in medical applications. For example, EVA resin emits an odor when extruded at high temperatures. While EVA resin is known to have poor low-temperature stability, it degrades at high processing temperatures, resulting in the formation of gels and black spots within the laminate, contaminating the extrusion molding system. Therefore, there is a need for an alternative tube structure that simplifies the extrusion molding process and eliminates concerns regarding the chemical properties of the binder layer by providing a material that does not require a binder layer for adhesion.

[0018] Accordingly, in one embodiment of the present invention, a continuous double-layer tube without a binding layer is provided. The continuous tube has an inner layer comprising a polyethylene (PE) composition and an outer layer comprising a thermoplastic elastomer (TPE). The inner and outer layers are arranged concentrically without an intermediate layer between them.

[0019] The materials of the inner layer and the outer layer are selected to be free of polyvinyl chloride. Therefore, the continuous tube disclosed in the present invention does not contain polyvinyl chloride, and thus can be used for the administration of drug molecules with strict In-Use (IFU) requirements.

[0020] In some embodiments, the inner layer comprises low-density polyethylene (LDPE). LDPE can be manufactured in translucent and opaque variants depending on the specific application. For example, in some embodiments, the tube may be required to be used for the administration of photosensitive drug molecules. In such applications, an opaque variant of LDPE can be used as the inner layer. In some embodiments, the inner layer transmits visible light.

[0021] In some embodiments, the inner layer comprises linear low-density polyethylene (LLDPE), such as a copolymer of ethylene and an α-olefin. Non-limiting examples of α-olefins that can be used for LLDPE include butene, hexene, and octene. In some embodiments, the inner layer comprises an ethylene-octene copolymer.

[0022] In some embodiments, the outer layer TPE comprises a styrenic block copolymer. Non-limiting examples of styrenic block copolymers include styrene-butadiene-styrene (SBS), styrene-ethylene-butylene-styrene (SEBS), styrene-isoprene block copolymer (SIS), styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-ethylene-propylene-styrene (SEEPS), or combinations thereof.

[0023] In some embodiments, the outer layer TPE can be blended with a polyolefin, such as a polypropylene or polyethylene composition, depending on the specific application for which the tube is used.

[0024] In some embodiments, the outer layer may further contain additives. Examples of additives include, but are not limited to, lubricants (slip agents), antioxidants, ultraviolet and blue light blocking additives, or combinations thereof. In some embodiments, the additives may include light-blocking additives that prevent the tube from transmitting visible light and / or ultraviolet light. In some embodiments, the outer layer transmits visible light.

[0025] Conventional multilayer tubes have a relatively thin inner layer, but the continuous tube of the present invention can be manufactured by arbitrarily and appropriately setting the ratio of the thickness of the inner layer to the outer layer. In some embodiments, the inner layer may have a thickness ranging from about 0.1% to about 20% of the thickness of the outer layer. For example, the ratio of the thickness of the inner layer to the thickness of the outer layer is approximately 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.25%, 1.5%, 1.75%, 2.0%, 2.25%, 2.5%, 2.75%, 3.0%, 3.25%, 3.5%, 3.75%, 4.0%, 4.25%, 4.5%, 4.75%, 5.0%, 5.25%, 5.5%, 5.75%, 6.0%, 6.25%, 6.5%, 6.75%, and 7. 0.0%, approximately 7.25%, approximately 7.5%, approximately 7.75%, approximately 8.0%, approximately 8.25%, approximately 8.5%, approximately 8.75%, approximately 9.0%, approximately 9.25%, approximately 9.5%, approximately 9.75%, approximately 10%, approximately 10.5%, approximately 11%, approximately 11.5%, approximately 12%, approximately 12.5%, approximately 13%, approximately 13.5%, approximately 14%, approximately 14.5%, approximately 15%, approximately 15.5%, approximately 16%, approximately 16.5%, approximately 17%, approximately 17.5%, approximately 18%, approximately 18.5%, approximately 19%, approximately 19.5%, approximately 20%, or any other ratio between any two of these ratios.

[0026] As used in this invention, the term "about" is relative to the actual value stated, as understood by those skilled in the art, and allows for approximation, inaccuracy, and limitations of measurement under the relevant circumstances. In one or more embodiments, the terms "about," "substantially," and "approximately" may provide industry-accepted tolerances and / or relatives between items for each term. Examples include tolerances ranging from less than 1% to 5% of the actual value stated, and other appropriate tolerances.

[0027] In some embodiments, the thickness of the inner layer may range from about 0.01 mm to about 1 mm. For example, the thickness of the inner layer may be about 0.01 mm, about 0.02 mm, about 0.03 mm, about 0.04 mm, about 0.05 mm, about 0.06 mm, about 0.07 mm, about 0.08 mm, about 0.09 mm, about 0.1 mm, about 0.15 mm, about 0.2 mm, about 0.25 mm, about 0.3 mm, about 0.35 mm, about 0.4 mm, about 0.45 mm, about 0.5 mm, about 0.55 mm, about 0.6 mm, about 0.65 mm, about 0.7 mm, about 0.75 mm, about 0.8 mm, about 0.85 mm, about 0.9 mm, about 0.95 mm, about 1.0 mm, or any other thickness between any two of these thicknesses.

[0028] In some embodiments, the thickness of the outer layer may range from approximately 0.05 mm to approximately 10 mm. Therefore, for example, the thickness of the outer layer may be approximately 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.125 mm, 0.15 mm, 0.175 mm, 0.2 mm, 0.225 mm, 0.25 mm, 0.275 mm, 0.3 mm, 0.325 mm, 0.35 mm, 0.375 mm, 0.4 mm, 0.425 mm, 0.45 mm, 0.475 mm, 0.5 mm, 0.525 mm, 0.55 mm, 0.575 mm, 0.6 mm, 0.625 mm, 0.65 mm, 0.675 mm, and 0.7 mm. m, approximately 0.725 mm, approximately 0.75 mm, approximately 0.775 mm, approximately 0.8 mm, approximately 0.825 mm, approximately 0.85 mm, approximately 0.875 mm, approximately 0.9 mm, approximately 0.925 mm, approximately 0.95 mm, approximately 0.975 mm, approximately 1.0 mm, approximately 1.5 mm, approximately 2.0 mm, approximately 2.5 mm, approximately 3.0 mm, approximately 3.5 mm, approximately 4.0 mm, approximately 4.5 mm, approximately 5.0 mm, approximately 5.5 mm, approximately 6.0 mm, approximately 6.5 mm, approximately 7.0 mm, approximately 7.5 mm, approximately 8.0 mm, approximately 8.5 mm, approximately 9.0 mm, approximately 9.5 mm, approximately 10.0 mm, or any other thickness between any two of these thicknesses.

[0029] In a continuous tube, the outer layer is arranged concentrically on top of the inner layer, and the outer layer is in direct contact with the inner layer without any intermediate layer in between. In other words, there is no adhesive or bonding layer between the inner and outer layers.

[0030] While we do not wish to be limited by any particular theory, delamination between the inner and outer layers can be prevented by selecting materials that have similar tensile properties. In some embodiments, the tensile elongations of the inner and outer layer materials may be within about 10% of each other. For example, the tensile elongation of the inner layer at fracture may be in the range of about 500% to about 700%, or about 600%, or about 650%. Similarly, the tensile elongation of the outer layer at fracture may be in the range of about 500% to about 700%, or about 600% to about 700%, or about 620% to about 670%.

[0031] In some embodiments, the inner layer material is selected to have low adsorption of nitroglycerin and / or other drug molecules. For example, the inner layer material is selected such that the amount of nitroglycerin adsorbed to the material is about 10% or less compared to the amount of nitroglycerin adsorbed to polyvinyl chloride. In some embodiments, the inner layer material is specifically selected to have low adsorption and reactivity to one or more drugs selected from aldesleukine, calcitriol, carmustine, chlordiazepoxide hydrochloride, diazepam, insulin, isosorbide dinitrate, lorazepam, miconazole, nitroglycerin, sufentanil citrate, thiopental sodium, urokinase, and warfarin sodium.

[0032] Accordingly, according to another aspect of the present invention, an infusion set for drug administration is provided. The infusion set may include a continuous tube and a medical connector as disclosed herein. Medical connectors that can enjoy the advantages of the tube of the present invention include, but are not limited to, connectors made of acrylic polymer materials such as acrylonitrile-butadiene-styrene (ABS), methyl methacrylate-acrylonitrile-butadiene-styrene (mABS), acrylic-polycarbonate materials, polyester, polycarbonate, and acrylic.

[0033] In some embodiments, the infusion set includes a continuous tube according to the Disclosure, which may be fitted and coupled to a medical connector by solvent bonding. In some embodiments, solvent bonding involves applying a thin solvent layer to one or both of the contact surfaces, for example, the surface of the tube and the surface of the medical connector, then bringing the two surfaces into contact and holding them in place until a seal is formed. The contact surface of the tube may be the inner diameter, outer diameter, or both, depending on whether the bonding layer is an inner layer, an outer layer, or both. The solvent is applied to the inner surface, the outer surface, or both.

[0034] The solvents that can be used for solvent bonding of the tubes according to the present invention are not limited to, but include one or more of the following: alcohols (e.g., methanol, ethanol, isopropanol, propanol, butanol, pentanol, benzyl alcohol), glycols (e.g., diethylene glycol, propylene glycol), ethers (e.g., dioxolane, tetrahydrofuran, 1,3-dioxane), ketones (e.g., acetone, methyl ethyl ketone, cyclohexanone), esters (e.g., ethyl acetate, ethyl formate), and amides (e.g., dimethylformamide, dimethylacetamide, diethylacetamide).

[0035] According to another aspect of the present invention, a method for manufacturing a continuous tube is provided herein. In some embodiments, the method involves co-extruding a polyethylene composition together with a thermoplastic elastomer (TPE) resin without providing an adhesive or binding layer between them. In other words, the polyethylene composition and the TPE resin are co-extruded so that a layer of the polyethylene composition is concentrically formed on the inner wall of a circular layer formed by the TPE resin, without any adhesive or binding layer between them.

[0036] The materials for the inner and outer layers are selected to be polyvinyl chloride-free. Therefore, in some embodiments, the inner layer may be low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE).

[0037] In some embodiments, the outer TPE resin comprises a styrene-based block copolymer. Non-limiting examples of styrene-based block copolymers include styrene-butadiene-styrene (SBS), styrene-ethylene-butylene-styrene (SEBS), styrene-isoprene block copolymer (SIS), styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-ethylene-propylene-styrene (SEEPS), or combinations thereof. In some embodiments, the outer TPE may be blended with a polyolefin, such as a polypropylene or polyethylene composition, depending on the specific application in which the tube is used.

[0038] In some embodiments, the outer layer may further include additives such as lubricants, antioxidants, UV-blocking additives, and blue-light-blocking additives, or combinations thereof. In some embodiments, the additives may include light-blocking additives that make the tube opaque to visible light and / or ultraviolet light. In some embodiments, the material of the outer layer is selected such that the outer layer is transparent to visible light.

[0039] The inner layer may have a thickness ranging from approximately 0.1% to approximately 20% of the thickness of the outer layer. Therefore, for example, depending on the amount of polyethylene composition co-extruded with the TPE resin, it is possible to form an inner layer with a thickness ranging from approximately 0.01 mm to approximately 1 mm. Similarly, depending on the amount of TPE resin used during the manufacturing process, it is possible to form an outer layer with a thickness ranging from approximately 0.05 mm to approximately 10 mm.

[0040] (Examples) Continuous tubes were formed by co-extruding medical-grade polyethylene with TPE resin. The selected PE grade was ENGAGE® 8480K Health+ polyolefin elastomer. This grade is an ethylene-octene copolymer with a tensile elongation of 660%. In this study, two TPE compositions (MD50278 and MD42275) with tensile elongations of 620% and 670%, respectively, were selected from Teknor Apex.

[0041] Figures 2A and 2B show cross-sectional images of a PE-lined tube with MD50278 TPE as the outer layer (Figure 2A) and a PE-lined tube with MD42275 TPE as the outer layer (Figure 2B), respectively. These figures show that the thickness of the PE inner layer is approximately 0.0127 mm in Figure 2A and approximately 0.0106 mm in Figure 2B.

[0042] To evaluate the durability of the PE laminated onto the inner TPE tube substrate, this study used two types of blue-colored PVC tubes with PE liners (TC50015844 and 10013072) with a bonding layer as benchmarks. The comparison was performed using the following two test methods. (a) Open and close the pinch clamp or roller clamp 63 times and observe delamination. (b) Cut open the tube and scrape the inner surface with a blade to remove the PE layer from the tube substrate, and observe its durability.

[0043] The value 63 was selected to simulate typical usage conditions in a hospital setting, namely, administering medication to a patient via tube infusion nine times a day for a maximum of seven days.

[0044] (Example 1: Clamp Test) In each tube, the flow was started or stopped 63 times using a standard pinch clamp. As can be seen in Figures 3A (TC50015844 PVC tube with PE liner), 3B (10013072 PVC tube with PE liner), 4A (TPE MD50278 with PE liner), and 4B (TPE MD40275 with PE liner), this test showed superior adhesion between PE and TPE compared to PVC tubes with PE liners, even without a bonding layer. The TPE tubes with PE liners showed no signs of delamination whatsoever.

[0045] In another test, the flow in each tube was started or stopped 63 times using a standard roller clamp. Figures 5A-5B (TC50015844 PE-lined PVC tube and 10013072 PE-lined PVC tube, respectively) and Figures 6A-6B (PE-lined TPE MD50278 and PE-lined TPE MD40275, respectively) show that no signs of delamination were observed in the delamination test after 63 start-and-stop cycles using a roller clamp.

[0046] (Example 2: Peel test) Different tubes were cut open to expose their inner surfaces, and these surfaces were scraped (scraped) with a blade. Figure 7 shows a comparison between TPE tubes with PE liners (labeled MD50278 and MD40275) and PVC tubes with PE liners (labeled TC50015844 and TC50013072). As shown in Figure 7, when the inner layers were tested by strongly scraping with a blade, the layers delaminated in the two PVC samples with PE liners, but no delamination was observed in the TPE tubes with PE liners. These test results indicate that PE adheres strongly to the TPE substrate even without a bonding layer.

[0047] (Explanation of the terms of this technology) Examples of various aspects of this disclosure are described below as numbered clauses (1, 2, 3, etc.) for convenience. These are provided as examples only and do not limit the technology. The identification of drawings and reference numbers is provided below solely for illustrative and explanatory purposes, and the clauses are not limited to their identification.

[0048] Clause 1: A continuous tube comprising an inner layer containing a polyethylene composition and an outer layer containing a thermoplastic elastomer (TPE), wherein the inner layer and the outer layer are concentrically arranged without an intermediate layer between them.

[0049] Clause 2: A continuous tube as described in Clause 1, wherein the inner layer comprises low-density polyethylene or a copolymer of ethylene and α-olefin.

[0050] Clause 3: A continuous tube as described in Clause 2, wherein the inner layer comprises an ethylene-octene copolymer.

[0051] Clause 4: A continuous tube as described in any one of Clauses 1 to 3, wherein the TPE comprises a styrene-based block copolymer.

[0052] Clause 5: A continuous tube as described in Clause 4, wherein the TPE comprises styrene-butadiene-styrene (SBS), styrene-ethylene-butylene-styrene (SEBS), styrene-isoprene block copolymer (SIS), styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-ethylene-propylene-styrene (SEEPS), or a combination thereof.

[0053] Clause 6: A continuous tube as described in Clause 4, wherein the TPE is blended with a polyolefin.

[0054] Clause 7: A continuous tube as described in any one of Clauses 1 to 6, wherein the outer layer further comprises one or more of the lubricants, antioxidants, and UV-blocking additives.

[0055] Clause 8: A continuous tube as described in any one of Clauses 1 to 7, wherein the inner layer has a thickness ranging from 0.01 mm to 1 mm.

[0056] Clause 9: A continuous tube as described in any one of Clauses 1 to 8, wherein the inner polyethylene material and the outer TPE material have a tensile elongation of no more than 10% relative to each other.

[0057] Clause 10: A continuous tube as described in any one of Clauses 1 to 9, wherein the inner and outer layers are resistant to delamination after pinch clamping or roller clamping.

[0058] Clause 11: A continuous tube as described in any one of Clauses 1 to 10, wherein the inner layer exhibits less than 10% nitroglycerin adsorption, indicated by polyvinyl chloride.

[0059] Clause 12: A continuous tube as described in any one of Clauses 1 to 11, wherein the continuous tube is a medical tube for administering medical fluids by infusion.

[0060] Clause 13: A continuous tube as described in any one of Clauses 1 to 12, wherein the continuous tube does not contain polyvinyl chloride.

[0061] Clause 14: A continuous tube as described in any one of Clauses 1 to 13, wherein the inner layer has a thickness of about 1% to about 20% of the thickness of the outer layer.

[0062] Clause 15: A continuous tube as described in any one of Clauses 1 to 14, wherein the continuous tube is transparent to visible light.

[0063] Clause 16: An infusion set having a continuous tube as described in Clause 1, coupled to a medical connector.

[0064] Clause 17: An infusion set as described in Clause 16, which is used to infuse drugs selected from the group consisting of aldezleukin, calcitriol, carmustine, chlordiazepoxide hydrochloride, diazepam, insulin, isosorbide dinitrate, lorazepam, miconazole, nitroglycerin, sufentanil citrate, thiopental sodium, urokinase, and warfarin sodium.

[0065] Clause 18: A method for preparing a continuous tube as described in any one of Clauses 1 to 15, comprising co-extruding a polyethylene composition with a thermoplastic elastomer resin without providing an adhesive or binding layer between them.

[0066] Clause 19: A method according to Clause 18, wherein the polyethylene composition comprises low-density polyethylene or a copolymer of ethylene and α-olefin.

[0067] Clause 20: A method according to any one of Clauses 18 to 19, wherein the TPE resin comprises a styrene-based block copolymer.

[0068] (Other considerations) In some embodiments, any clause described herein may be dependent on any independent clause or any dependent clause. In one embodiment, any clause (e.g., a dependent clause or an independent clause) may be combined with any one or more other clauses (e.g., dependent clauses or independent clauses). In one embodiment, a claim may include some or all of the words (e.g., steps, actions, means, or components) contained in a clause, sentence, phrase, or paragraph. In one embodiment, a claim may include some or all of the words contained in one or more clauses, sentences, phrases, or paragraphs. In one embodiment, some of the words contained in each clause, sentence, phrase, or paragraph may be deleted. In one embodiment, additional words or elements may be added to a clause, sentence, phrase, or paragraph. In one embodiment, the Art may be carried out without utilizing some of the components, elements, functions, or actions described in the Invention. In one embodiment, the Art may be carried out by utilizing additional components, elements, functions, or actions.

[0069] The above description is provided so that those skilled in the art can implement the various configurations described in the present invention. The art has been described in particular with reference to various drawings and configurations, but these are for illustrative purposes only and should not be construed as limiting the scope of the art.

[0070] Numerous other methods of carrying out this technology may exist. The various functions and elements described in this invention may be classified in a different way than those illustrated, without departing from the scope of this technology. Various modifications to these configurations will be readily understood by those skilled in the art, and the general principles defined in this invention can be applied to other configurations as well. Therefore, many changes and modifications can be made to this technology by those skilled in the art, but without departing from the scope of this technology.

[0071] It should be understood that the specific sequence or hierarchy in the disclosed process is an example of an exemplary approach. Based on design preferences, the specific sequence or hierarchy in the process may be rearranged. Some steps may be performed simultaneously. The claims relating to the attached method illustrate elements of various processes in an example sequence and are not intended to be limited to the specific sequence or hierarchy presented.

[0072] As used herein, the phrase “at least one” modifies the entire list, rather than each individual item, when it precedes a list of items and is used with “and” or “or” to separate items. The phrase “at least one” does not require that at least one of each listed item be selected, but rather allows for meanings that include at least one of any item and / or at least one of any combination of items and / or at least one of each item. For example, the phrases “at least one of A, B, and C” or “at least one of A, B, or C” refer to A only, B only, or C only, any combination of A, B, and C, and / or at least one of each of A, B, and C, respectively.

[0073] Furthermore, wherever the terms “include,” “have,” or similar terms are used in the description or claims, such terms are intended to have a comprehensive meaning, similar to how “comprise” is interpreted when used as a transition term in a claim.

[0074] In one or more ways, terms such as “about,” “substantially,” and “approximately” may provide industry-recognized tolerances and / or relative terms between items, for each term. For example, tolerances ranging from less than 1% to 5%.

[0075] In this specification, the term “exemplary” means “serving as an example, case, or illustration.” Embodiments described as “exemplary” in the present invention should not necessarily be construed as being preferable or advantageous to other embodiments.

[0076] In this specification, when an element is referred to in the singular form, it means "one or more" and not "one" unless otherwise explicitly stated. The masculine pronoun (e.g., his) includes the feminine and neuter forms (e.g., her and its), and vice versa. The term "some" means one or more. Underlined and / or italicized headings and subheadings are for convenience only and do not limit the Art, nor are they referenced in connection with the interpretation of the Art. All structural and functional equivalents to elements of the various configurations described throughout this disclosure, known or to those skilled in the art, are expressly incorporated into the present invention and intended to be included in the Art. Furthermore, nothing disclosed herein, whether expressly stated above or not, is intended to be made public.

[0077] While the detailed description includes many specific details, these should not be interpreted as limiting the scope of the Art, but merely illustrating different examples and embodiments of the Art. It should be understood that the scope of the Art also includes other embodiments not described in detail above. The arrangement, operation, and details of the methods and apparatus of the Art disclosed herein may be modified, altered, and transformed in various ways without departing from the scope. Unless otherwise explicitly stated, when an element is referred to in the singular, it means "one or more," not "one and only." Furthermore, addressing all problems solvable by different embodiments of this disclosure (or having all attainable advantages) is not a requirement for an apparatus or method to be included within the scope of this disclosure. The use of "can" and its derivatives herein should be understood as "possible" or "optional," not as an affirmative ability.

Claims

1. It is a continuous tube, An inner layer containing a polyethylene composition, and An outer layer containing thermoplastic elastomer (TPE), It has, A continuous tube in which the inner layer and the outer layer are arranged concentrically without an intermediate layer between them.

2. The continuous tube according to claim 1, wherein the inner layer comprises low-density polyethylene or a copolymer of ethylene and α-olefin.

3. The continuous tube according to claim 2, wherein the inner layer comprises an ethylene-octene copolymer.

4. The continuous tube according to any one of claims 1 to 3, wherein the TPE comprises a styrene-based block copolymer.

5. The continuous tube according to claim 4, wherein the TPE includes styrene-butadiene-styrene (SBS), styrene-ethylene-butylene-styrene (SEBS), styrene-isoprene block copolymer (SIS), styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-ethylene-propylene-styrene (SEEPS), or a combination thereof.

6. The continuous tube according to claim 4, wherein the TPE is blended with a polyolefin.

7. The continuous tube according to any one of claims 1 to 6, wherein the outer layer further comprises one or more of a lubricant, an antioxidant, and an ultraviolet-blocking additive.

8. The continuous tube according to any one of claims 1 to 7, wherein the inner layer has a thickness in the range of 0.01 mm to 1 mm.

9. A continuous tube according to any one of claims 1 to 8, wherein the inner polyethylene material and the outer TPE material have a tensile elongation of no more than 10% of each other.

10. The continuous tube according to any one of claims 1 to 9, wherein the inner layer and the outer layer are resistant to delamination after pinch clamping or roller clamping.

11. The continuous tube according to any one of claims 1 to 10, wherein the inner layer exhibits nitroglycerin adsorption of less than 10% of the nitroglycerin adsorption represented by polyvinyl chloride.

12. The continuous tube according to any one of claims 1 to 11, wherein the continuous tube is a medical tube for administering medical fluids by injection.

13. The continuous tube according to any one of claims 1 to 12, wherein the continuous tube does not contain polyvinyl chloride.

14. The continuous tube according to any one of claims 1 to 13, wherein the inner layer has a thickness of about 1% to about 20% of the thickness of the outer layer.

15. The continuous tube according to any one of claims 1 to 14, wherein the continuous tube transmits visible light.

16. An infusion set having a continuous tube according to any one of claims 1 to 15, coupled to a medical connector.

17. The infusion set according to claim 16, wherein the infusion set is used to infuse a drug selected from the group consisting of aldesleukin, calcitriol, carmustine, chlordiazepoxide hydrochloride, diazepam, insulin, isosorbide dinitrate, lorazepam, miconazole, nitroglycerin, sufentanil citrate, thiopental sodium, urokinase, and warfarin sodium.

18. A method for preparing a continuous tube according to any one of claims 1 to 15, comprising co-extruding a polyethylene composition and a thermoplastic elastomer resin without providing an adhesive or bonding layer between them.

19. The method according to claim 18, wherein the polyethylene composition comprises low-density polyethylene or a copolymer of ethylene and α-olefin.

20. The method according to claim 18 or claim 19, wherein the TPE resin comprises a styrene-based block copolymer.

Images