Multilayer pipe with an intermediate layer containing an additive

Abstract

Tubing, such as medical tubing for administering intravenous fluids, may include an inner layer, an outer layer arranged concentrically around and around the inner layer, and an intermediate layer between the inner and outer layers. The intermediate layer may include photoprotective additives.

Description

Technical Field

[0001] This disclosure relates generally to tubing, and more particularly to medical tubing for administering medical fluids by infusion. Background Technology

[0002] Plastic tubing is widely used in the medical field, particularly for patient analysis and treatment procedures. However, medical tubing requires different and sometimes incompatible specifications. For example, medical tubing should be inert and prevent contamination of the fluids transported through it. However, many plastic materials with these properties tend not to be flexible. Yet, in many applications, medical tubing is tangled or clamped, or used with infusion pumps that compress the tubing to pass fluid through it. Such applications require flexible tubing.

[0003] To meet the diverse requirements of medical tubing, it is manufactured with multiple layers of different polymer materials or with additives (such as plasticizers) to modify its properties. However, multilayer tubing made of different materials can delaminate, thus sometimes requiring adhesive "bonding layers" between incompatible materials. Furthermore, tubing made with additives has the potential to migrate into and contaminate the fluids it carries. Additionally, plasticized polymer materials such as plasticized PVC can be sticky and cause tubing blockages and tears. Summary of the Invention

[0004] Given the challenges mentioned above, there is a continued demand for medical tubing that can meet the diverse needs of medical applications.

[0005] According to various embodiments of this disclosure, tubing, such as medical tubing for administering intravenous fluids, may include an inner layer, an outer layer arranged concentrically around and surrounding the inner layer, and an intermediate layer between the inner and outer layers. The intermediate layer may include a photoprotective additive.

[0006] According to various embodiments of this disclosure, a method for forming a multilayer pipe may include co-extruded a base polymer resin material into an inner layer, an outer layer, and an intermediate layer of the multilayer pipe. The intermediate layer may include a photoprotective additive having a predetermined concentration.

[0007] According to this disclosure, additional advantages of the subject matter of the invention will become apparent to those skilled in the art from the following detailed description, wherein only certain aspects of the subject matter are shown and described simply by way of example. As will be appreciated, the subject matter is capable of other and different configurations, and several details thereof can be modified in various other respects, all without departing from the subject matter. Therefore, the drawings and description should be considered illustrative in nature rather than restrictive. Attached Figure Description

[0008] The accompanying drawings, which are included in and form part of this specification and are used to provide a further understanding of the specification, illustrate the disclosed embodiments and, together with the specification, serve to explain the principles of the disclosed embodiments. In the drawings:

[0009] Figure 1 A cross-sectional view of a three-layer tubing according to one aspect of this disclosure is shown. Detailed Implementation

[0010] The specific embodiments described below depict various configurations of the present subject matter, and are not intended to represent the only configuration in which the present subject matter can be practiced. To provide a comprehensive understanding of the subject matter, detailed descriptions include specific details. Therefore, dimensions regarding certain aspects are provided as non-limiting examples. However, it will be apparent to those skilled in the art that the present subject matter can be practiced without these specific details. In some instances, well-known structures and elements are shown in block diagram form to avoid obscuring the concept throughout the present subject matter.

[0011] 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, depending on the desired application or implementation.

[0012] This subject matter relates to tubing, and more particularly to medical tubing for administering medical fluids by infusion. Various aspects of this disclosure provide a medical-grade tubing with a sandwich three-layer structure comprising an inner layer, an outer layer, and an intermediate layer between and connected to the inner and outer resin materials. In some embodiments, the inner, outer, and intermediate layers may be formed from the same base polymer resin material. This construction, where the inner, outer, and intermediate layers are formed from the same base polymer resin material, advantageously avoids the need for conventionally required connecting layers to maintain bonding between the multiple layers and prevent delamination of the tubing. For example, since each of the three layers uses the same compatible base resin having the same polarity and chemical composition, there is no need for connecting layers to prevent delamination of the inner, outer, and intermediate layers of the tubing.

[0013] Medical tubing may include a variety of additives and / or colorants. For example, medical tubing used to deliver drugs and nutrients to patients typically needs to meet essential clinical application requirements, such as photoprotection in the 250 to 450 nm range and at least 90% blockage to protect photosensitive medical fluids flowing into the tubing. Colorants may also be included in medical tubing as identifiers for specific clinical uses.

[0014] According to various embodiments of this disclosure, photoprotective additives and / or colorants can be incorporated into the carrier resin of the intermediate layer. The photoprotective additives can advantageously provide the aforementioned range of photoprotective capabilities to protect photosensitive medical fluids flowing in the tubing from light exposure that could otherwise degrade the fluids and / or alter their chemical composition, rendering them unsuitable for their intended use.

[0015] A further advantage of the above-described construction, which incorporates photoprotective additives and / or colorants into the intermediate layer, is that the inner layer acts as a barrier to prevent any potentially irritating chemicals in the photoprotective additives and / or colorants from leaking into the pharmaceutical fluid flowing in the lumen and otherwise contaminating the medical fluid.

[0016] Multilayer (e.g., three-layer) tubing, as described herein, can utilize separate chemical packages containing photoprotective additives, which are then incorporated into the carrier resin of the intermediate layer. The tubing can then be extruded as a single layer or multiple layers, as will be described in further detail below. As described herein, multilayer (e.g., three-layer) tubing is configured to withstand and pass stringent testing regulations for light-resistant infusion kits. For example, the National Medical Products Administration (NMPA) recently issued standard regulations for disposable light-resistant infusion kits, in which a low and high pH, ​​65% ethanol, and 50% PEG solution are circulated within the infusion kit at 37°C for 2 hours. The regulation considers the test a failure if the extracted medium is a darker color than the clear 65% ethanol and 50% PEG solution. In a further cFDA testing regulation, the infusion kit is incubated at 60°C for 24 hours, and then approximately 1 meter of the outer tubing layer is wiped with cotton. The regulation considers the test a failure if significant migration of colorant to the outer tubing layer is observed on the surface of the cotton used to wipe the tubing. The stringent testing conditions for the inner layer (chemical testing) and the outer layer (physical testing) necessitate an alternative method to maintain the integrity of the additives within the tube layers. Therefore, various embodiments of this disclosure relate to providing a three-layer tube design with an intermediate layer comprising an active photoprotective additive and / or colorant. The inner layer of the three-layer tube advantageously acts as a barrier to prevent direct contact between medical fluids and the photoprotective additive or colorant. The outer layer acts as another barrier to prevent the additives from migrating from the intermediate layer to the outer surface of the three-layer tube.

[0017] Another advantage of the tubing disclosed herein is that the intermediate layer may include one or more of colorants, UV blockers, radiopaque strips, and other additives. Such additives can be used to design colored and / or light-resistant tubing without concern about leaching of these additives into the fluid transported by the tubing, as the inner layer prevents their migration.

[0018] The three-layer tubing of this disclosure is particularly suitable for intravenous assemblies and / or infusion pumps for delivering intravenous fluid to a patient. Assemblies that connect intravenously to a fluid container and tubing, valves, fittings, and needles may be referred to as “intravenous assemblies” or “IV assemblies.” Infusion assemblies may include tubing according to this disclosure, which is incorporated into components of the IV assembly, such as medical connectors, drip chambers, Luer connectors, needles, check valves, filters, and needleless valves, to enable medical delivery to a patient either as a gravity-fed assembly or controlled by a medical pump for programmed medical delivery procedures.

[0019] Figure 1 A cross-sectional view of a three-layer tubing according to one aspect of the present disclosure is shown. As shown, the tubing, such as medical tubing 100, may include an inner layer 10, an outer layer 20 arranged concentrically around and surrounding the inner layer, and an intermediate layer 30 between the inner layer 10 and the outer layer 20. In some embodiments, the outer layer, inner layer, and intermediate layer may each be formed from the same base material. For example, the inner layer 10, outer layer 20, and intermediate layer 30 may be co-extruded from the same polymer resin material. Layers 10, 20, and 30 may be co-extruded such that the outer layer 20 directly contacts the intermediate layer 30, and the intermediate layer 30 subsequently directly contacts the inner layer 10 along the length of the tubing, without a connecting layer between the outer layer 20 and the inner layer 10 or between the inner layer 10 and the intermediate layer 30.

[0020] The aforementioned structure, in which the inner, outer, and intermediate layers 10, 20, and 30 are formed from the same base resin material, advantageously avoids the need for conventionally required connecting layers to maintain the bond between the multiple layers and prevent delamination of the pipe layers. For example, since each of the three layers uses the same compatible base resin with the same polarity and chemical composition, there is no need to provide connecting layers between them to prevent delamination of the pipe layers 10, 20, and 30.

[0021] According to some embodiments, the base resin material may include at least one or a combination of polyvinyl chloride (PVC), styrene block copolymer (SBC), polyolefin, thermoplastic polyurethane (TPU), polyester, polyether, silicone HCR, EPDM / PP, or other similar elastomer materials. The base resin polymer materials that can be used for layers 10, 20, and 30 of the tubing of this disclosure include, but are not limited to, medical-grade plastic materials such as polyvinyl chloride (PVC), copolymers thereof, and blends of such polymers. In some embodiments, medical-grade plastic materials such as PVC can be made flexible by including varying amounts of plasticizer.

[0022] For example, differences in flexibility or hardness can be achieved by including a smaller amount or a different type of plasticizer in the polymer material of the inner layer 10 than in the outer layer 20 and the intermediate layer 30. In some embodiments, the amount or type of plasticizer should be sufficient to advantageously make the hardness of the outer or intermediate layer at least about 5 hardness units less than that of the inner layer 10. In some embodiments, for example, the inner layer 10 may have a smaller amount of the same plasticizer than the outer layer 20 and the intermediate layer 30 to achieve higher hardness. In some aspects, phthalates such as di(2-ethylhexyl) phthalate (DEHP) and adipates such as di(2-ethylhexyl) adipate (DEHA) can be used as plasticizers in medical-grade PVC pipes.

[0023] According to various embodiments of this disclosure, the inner, outer, and intermediate layers 10, 20, and 30 may be made of the same base polymer resin material, but the intermediate layer 30 may include a photoprotective additive. The photoprotective additive may be dispersed in or otherwise included in the base resin material of the intermediate layer. In some embodiments, the photoprotective additive may include a predetermined concentration of an ultraviolet (UV) light absorber. For example, the photoprotective additive may include at least one of benzotriazole, benzophenone, or triazine, or combinations thereof, at a predetermined concentration. In some embodiments, the photoprotective additive may include a predetermined concentration of a blue light absorber.

[0024] According to various aspects of this disclosure, the intermediate layer may also contain a colorant or a mixture of colorants that are yellow, amber, or brown. For example, the colorant or colorant mixture may include organic dyes such as azo dyes, anthraquinone dyes, phthalocyanine, or inorganic pigments such as titanium dioxide, iron oxide, chromium oxide, and at least one or a combination of other metal oxides and metallic pigments. Since the inner layer 10 and the outer layer 20 can act as barriers to prevent colorant migration, such colorants can be used to design coloring intermediate layers without concern about such colorants leaching into fluids transported by pipes.

[0025] In some embodiments, the thickness of the intermediate layer 30 is less than the thickness of each of the inner layer 10 and the outer layer 20. For example, in some embodiments, the inner and outer layers 10 and 20 may each have a thickness ranging from 0.2 mm to 0.8 mm, for example, from 0.4 mm to 0.6 mm. The intermediate layer may have a thickness of 10% to 90% of that of the inner or outer layer, for example, less than 0.8 mm, less than 0.4 mm, or less than 0.2 mm. Given the specific wavelength of light incident on the tube 100, a construction with an intermediate layer thickness of less than 0.8 to 0.2 mm may be advantageous in increasing the light-blocking or protective capability of the intermediate layer 30. For example, a thinner intermediate layer may provide more desirable transmittance of light of a specific wavelength incident on the tube 100. In some embodiments, the combined thickness of the inner, outer, and intermediate layers may be less than or equal to 0.8 mm, wherein the thickness of the intermediate layer is less than the thickness of each of the inner layer 10 and the outer layer 20. Furthermore, in some embodiments, the tubing of this disclosure may have an inner diameter through which fluid flows, ranging from about 1.5 mm to about 6 mm, for example from 2 mm to 4 mm.

[0026] Therefore, introducing the aforementioned photoprotective additives or colorants into the intermediate layer 30 of the tubing advantageously provides at least the minimum necessary photoprotection capability in the range of 250 to 450 nm, with a minimum 90% blocking or minimum 10% transmittance. Thus, photosensitive medical fluids flowing in the tubing 100 can be protected from harmful light exposure that might otherwise degrade the photosensitive medical fluids and / or alter their chemical composition, making them potentially harmful to patients if they enter their bloodstream.

[0027] In some implementations, the intermediate layer may also include a radiopaque material. Radiopaque materials can be advantageously used as X-ray-sensitive tracking markers to identify the location of the tubing within the human body.

[0028] In some implementations, the intermediate layer may also include stripe identifiers. In some aspects, multiple tubes are connected to the patient's body at different locations. For example, the patient may have one or more of the following: intravenous (IV) tubes, subcutaneous tubes, epidural tubes, feeding tubes, arterial lines or conduits, or multiple drainage lines or conduits. In these cases, stripe identifiers can advantageously color-code the tubes to prevent incorrect medication from entering the wrong location on the body. Color coding helps ensure that medications or other medical fluids are easily identifiable and associated with the final location of the corresponding tube. Therefore, serious adverse effects associated with delivering the wrong medication to the wrong location on the body can be avoided.

[0029] According to various embodiments of this disclosure, a method of forming a multilayer tube 100 may include co-extruding a base polymer resin material into an inner layer 10, an outer layer 20, and an intermediate layer 30 of the multilayer tube. Layers 10, 20, and 30 may be co-extruded such that the outer layer 20 directly contacts the intermediate layer 30, and the intermediate layer 30 subsequently directly contacts the inner layer 10 along the tube length, without a connecting layer between the outer layer 20 and the inner layer 10 or between the inner layer 10 and the intermediate layer 30. The method of forming a multilayer tube may also include introducing a photoprotective additive having a predetermined concentration into the intermediate layer 30 prior to co-extrusion. In some embodiments, the photoprotective additive may include one or more of ultraviolet (UV) light absorbers or blue light absorbers, colorants or mixtures of colorants exhibiting yellow, amber, or brown hues, radiopaque materials, or stripe identifiers.

[0030] Therefore, various embodiments of this disclosure introduce active additives into an intermediate layer opposite to the inner or outer layer to minimize and avoid tube test failures caused by colorant migration to the outer surface of the tube as described above. More advantageously, various embodiments of this disclosure introduce active additives into an intermediate layer opposite to the inner or outer layer to reduce the potential risks associated with additives that migrate into the lumen and cause hazardous contamination by the applied fluid. Contamination may become more severe upon introduction of the fluid into the body, potentially leading to blood contamination.

[0031] Even more advantageously, since the inner, outer, and intermediate layers are made of the same polymer base material, these layers are more compatible and can be more easily fused together, thereby avoiding or minimizing the need for adhesive or bonding layers between the outer, inner, and intermediate layers, greatly simplifying and reducing the cost of the extrusion process for manufacturing such pipes.

[0032] In one or more aspects of this disclosure, a tubing includes an inner layer, an outer layer arranged concentrically around and surrounding the inner layer, and an intermediate layer between the inner and outer layers, wherein the intermediate layer includes a light-protective additive contained therein.

[0033] According to various aspects of this disclosure, the inner layer, outer layer, and intermediate layer are formed from the same base resin material. According to various aspects of this disclosure, the photoprotective additive is contained in the base resin material of the intermediate layer and contains at least one of a predetermined concentration of ultraviolet (UV) light absorber or blue light absorber. According to various aspects of this disclosure, the base resin material comprises plasticized polyvinyl chloride. According to various aspects of this disclosure, the base resin material comprises at least one of polyvinyl chloride, styrene block copolymer (SBC), polyolefin, thermoplastic polyurethane (TPU), polyester, polyether, silicone HCR, EPDM / PP, or other similar elastomer materials. According to various aspects of this disclosure, the intermediate layer further contains a colorant or a mixture of colorants exhibiting a yellow, amber, or brown color.

[0034] According to various aspects of this disclosure, the colorant or colorant mixture comprises organic dyes, such as azo dyes, anthraquinone dyes, phthalocyanines, or inorganic pigments, such as titanium dioxide, iron oxide, chromium oxide, and other metal oxides and metallic pigments. According to various aspects of this disclosure, the inner and outer layers are co-extruded in direct contact with the intermediate layer along the length of the tubing. According to various aspects of this disclosure, the thickness of the intermediate layer is less than the thickness of at least one of the inner or outer layers. According to various aspects of this disclosure, the thickness of the intermediate layer is greater than the thickness of at least one of the inner or outer layers. According to various aspects of this disclosure, the photoprotective additive comprises a UV light absorber, which comprises at least one of benzotriazole, benzophenone, or triazine, or combinations thereof. According to various aspects of this disclosure, the intermediate layer further comprises at least one of a stripe identifier or a radiopaque material.

[0035] According to one or more embodiments of this disclosure, a method of forming a multilayer pipe includes co-extruding a base polymer resin material into an inner layer, an outer layer, and an intermediate layer of the multilayer pipe, wherein the intermediate layer includes a photoprotective additive having a predetermined concentration.

[0036] According to various aspects of this disclosure, the photoprotective additive comprises at least one of a predetermined concentration of an ultraviolet (UV) light absorber or a blue light absorber. According to various aspects of this disclosure, the intermediate layer further comprises a predetermined concentration of a colorant or a mixture of colorants that give the intermediate layer a yellow, amber, or brown color. According to various aspects of this disclosure, the colorant or colorant mixture comprises organic dyes, such as azo dyes, anthraquinone dyes, phthalocyanines, or inorganic pigments, such as titanium dioxide, iron oxide, chromium oxide, and other metal oxides and metallic pigments.

[0037] According to various aspects of this disclosure, the intermediate layer is co-extruded to a thickness less than that of the inner and outer layers. According to various aspects of this disclosure, the intermediate layer is extruded to a thickness of less than 0.8 mm. According to various aspects of this disclosure, the base polymer resin material includes at least one selected from polyvinyl chloride, styrene block copolymer (SBC), polyolefin, thermoplastic polyurethane (TPU), polyester, polyether, silicone HCR, EPDM / PP, or other similar elastomer materials. According to various aspects of this disclosure, the intermediate layer further includes at least one selected from stripe markings or a radiopaque material.

[0038] It should be understood that any particular order or hierarchy of modules in the disclosed methods or processes is illustrative of the example methods. It is understood that, based on design or implementation preferences, the particular order or hierarchy of modules in the process may be rearranged, or all illustrated modules may be executed. In some implementations, any module may be executed simultaneously.

[0039] 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 techniques, and the subject matter techniques are not limited to these examples. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects.

[0040] Unless otherwise specified, mentioning an element in the singular does not mean "one and only one," but rather "one or more." Unless otherwise specified, the term "some" refers to one or more. Masculine pronouns (e.g., he) include feminine and neuter pronouns (e.g., she and it), and vice versa. Titles and subtitles, if any, are used for convenience only and do not limit the invention.

[0041] The term “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 superior to or advantageous over other aspects or designs. In fact, the various alternative configurations and operations described herein may be considered at least equivalent.

[0042] As used herein, the phrase "at least one" preceding a series of items, when separated by the term "or," modifies the list as a whole, not each item in the list. The phrase "at least one" does not require selection of at least one item; rather, it allows for the inclusion of at least one of any given 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.

[0043] Phrases such as "aspect" do not imply that the aspect is essential to the subject matter or that the aspect applies to all configurations of the subject matter. Disclosures associated with an aspect may apply to all configurations, or one or more configurations. An aspect may provide one or more examples. Phrases such as "aspect" may refer to one or more aspects, or vice versa. Phrases such as "implementation" do not imply that the implementation is essential to the subject matter or that the implementation applies to all configurations of the subject matter. Disclosures associated with an implementation may apply to all implementations, or one or more implementations. An implementation may provide one or more examples. Phrases such as "implementation" may refer to one or more implementations, or vice versa. Phrases such as "implementation" do not imply that the configuration is essential to the subject matter or that the configuration applies to all configurations of the subject matter. Disclosures associated with a configuration may apply to all configurations, or one or more configurations. A configuration may provide one or more examples. Phrases such as "configuration" may refer to one or more configurations, or vice versa.

[0044] In one respect, unless otherwise stated, all measurements, values, ratings, positions, sizes, dimensions, and other specifications set forth in this specification, including those in the appended claims, are approximate, not precise. In another respect, they are intended to have a reasonable range consistent with the functions associated with them and with the conventions of the art to which they pertain.

[0045] It should be understood that the specific order or hierarchy of the disclosed steps, operations, or processes is illustrative of the exemplary method. It is understood that the specific order or hierarchy of steps, operations, or processes can be rearranged based on design preferences. Some steps, operations, or processes may be performed simultaneously. Some or all steps, operations, or processes may be performed automatically without user intervention. The appended method claims (if any) present the elements of the respective steps, operations, or processes in a sample order and are not intended to limit one to the specific order or hierarchy presented.

[0046] All structural and functional equivalents of the elements of the aspects described throughout this disclosure that are known to those skilled in the art or that subsequently became known are expressly referenced herein and intended to be covered by the claims. Furthermore, nothing disclosed herein is intended for public use, whether or not such disclosure is expressly recited in the claims. No claim element is to be construed in accordance with 35 USC.§112(f) unless the element is expressly stated using the phrase “for means of…” or, in the case of a method claim, using the phrase “for the step of…”. Moreover, with regard to the use of terms such as “comprising,” “having,” etc., such terms are intended to be included in a manner similar to the term “including,” as “comprising” is interpreted as a transition in a claim.

[0047] The title, background, summary, description of the drawings, and abstract of this disclosure are incorporated herein by reference and provided as illustrative examples rather than limiting descriptions. It is committed and is understood to be unsuitable for limiting the scope or meaning of the claims. Furthermore, in the detailed description, it will become apparent that the description provides illustrative examples, and various features are combined in various embodiments for the purpose of simplifying the disclosure. The method of this disclosure is not to be construed as an attempt to reflect an attempt to claim more features than are expressly recited in each claim. Rather, as reflected in the appended claims, the inventive subject matter lies in all features of fewer than those in a single disclosure configuration or operation. The following claims are thus incorporated into the detailed description, wherein each claim is independently claimed as a separate subject matter.

[0048] 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 include all legal equivalents. In any case, the claims are not intended to include subject matter that does not satisfy the requirements of 35 USC §101, 102, or 103, nor should they be interpreted in this manner.

Claims

1. A tubing comprising an inner layer, an outer layer disposed concentrically around and surrounding the inner layer, and an intermediate layer between the inner layer and the outer layer, wherein the intermediate layer includes a light protection additive contained therein, the intermediate layer provides light protection from 250 to 450 nm with a minimum of 90% blockage, and the inner layer and the outer layer are barriers that prevent migration of the light protection additive from the intermediate layer, wherein the thickness of the intermediate layer is less than the thickness of at least one of the inner layer and the outer layer, wherein the inner layer, the outer layer, and the intermediate layer are formed from the same base resin material, wherein the hardness of each of the outer layer and the intermediate layer is at least 5 hardness units less than the hardness of the inner layer.

2. The tubing of claim 1, wherein the light protection additive is contained in the base resin material of the intermediate layer and includes a predetermined concentration of at least one of an ultraviolet (UV) light absorber or a blue light absorber.

3. The tubing of claim 1, wherein the base resin material comprises plasticized polyvinyl chloride.

4. The tubing of claim 1, wherein the base resin material comprises at least one of polyvinyl chloride, styrene block copolymer (SBC), polyolefin, thermoplastic polyurethane (TPU), polyester, polyether, silicone HCR, EPDM / PP, or other similar elastomeric material.

5. The tubing of claim 1, wherein the intermediate layer further comprises a colorant that exhibits a yellow, amber, or brown color.

6. The tubing of claim 5, wherein the colorant is a mixture of colorants.

7. The tubing of claim 5 or 6, wherein the colorant comprises an organic dye or an inorganic pigment.

8. The tubing of claim 7, wherein the organic dye comprises an azo dye, an anthraquinone dye, and a phthalocyanine.

9. The tubing of claim 7, wherein the inorganic pigment comprises titanium dioxide, iron oxide, chromium oxide, and other metal oxides and metal pigments.

10. The tubing of claim 1, wherein the inner layer and the outer layer are co-extruded in direct contact with the intermediate layer along the length of the tubing.

11. The tubing of claim 1, wherein the light protection additive comprises a UV light absorber, the UV light absorber comprising at least one of a benzotriazole, a benzophenone, or a triazine, or a combination thereof.

12. The tubing of claim 1, wherein the intermediate layer further comprises a striped identifier.

13. The tubing of claim 1, wherein the intermediate layer further comprises a radio-opaque material.

14. A method of forming a multi-layer tubing, comprising: co-extruding a base polymeric resin material into an inner layer, an outer layer disposed concentrically around and surrounding the inner layer, and an intermediate layer between the inner layer and the outer layer of a multi-layer tubing, wherein the intermediate layer includes a light protection additive contained therein, the intermediate layer provides light protection from 250 to 450 nm with a minimum of 90% blockage, and the inner layer and the outer layer are barriers that prevent migration of the light protection additive from the intermediate layer, wherein the intermediate layer is co-extruded to a thickness that is less than a thickness of at least one of the inner layer and the outer layer, wherein the inner layer, the outer layer, and the intermediate layer are formed from the same base resin material, and wherein a hardness of each of the outer layer and the intermediate layer is at least 5 hardness units less than a hardness of the inner layer.

15. The method of claim 14, wherein the light protection additive comprises a predetermined concentration of at least one of an ultraviolet (UV) light absorber or a blue light absorber.

16. The method of claim 14, wherein the intermediate layer further comprises a predetermined concentration of a colorant that causes the intermediate layer to exhibit a yellow, amber, or brown color.

17. The method of claim 16, wherein the colorant is a mixture of colorants.

18. The method of claim 16 or 17, wherein the colorant comprises an organic dye or an inorganic pigment.

19. The method of claim 18, wherein the organic dye comprises an azo dye, an anthraquinone dye, and a phthalocyanine.

20. The method of claim 18, wherein the inorganic pigment comprises titanium dioxide, iron oxide, chromium oxide, and other metal oxides and metal pigments.

21. The method of claim 14, wherein the intermediate layer is extruded to a thickness of less than 0.8 mm.

22. The method of claim 14, wherein the base polymer resin material comprises at least one of polyvinyl chloride, styrene block copolymer (SBC), polyolefin, thermoplastic polyurethane (TPU), polyester, polyether, silicone HCR, EPDM / PP, or other similar elastomeric materials.

23. The method of claim 14, wherein the intermediate layer further comprises a striped identifier.

24. The method of claim 14, wherein the intermediate layer further comprises a radiopaque material.

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