An integrated two-color needle guard

Abstract

The present invention belongs to the field of medical device technology, and in particular relates to an integrated two-color needle guard cap. The integrated two-color needle guard cap includes an inner guard cap and an outer guard cap, the inner guard cap is made of a thermoplastic elastomer; the outer guard cap is sleeved outside the inner guard cap, and the outer guard cap and the inner guard cap form an integrated structure; an inner cavity channel is provided in the inner guard cap. The inner guard cap and the outer guard cap of the present invention are integrally formed by injection molding in a clean room, which has a longer service life and lower cost. Moreover, the process is completed in the clean room, and no cleaning is required. It can be put into use after local siliconization. Thermoplastic elastomer (TPE) is used as the inner guard cap of the integrated two-color needle guard cap, and the inner guard cap will not turn yellow or white, making it safer and more reliable to use. Moreover, its simple and three-dimensional structural design makes it more practical and more convenient to use.

Description

Technical Field

[0001] The present invention belongs to the field of medicine packaging, and in particular relates to an integrated two-color needle protective cap. Background Art

[0002] Currently, the commonly used needle caps are assembled from PP / PE caps and rubber caps. The rubber caps currently produced on the market have many complex processes, low pass rates, high equipment investment, large floor space, high production costs, waste of resources, and serious environmental pollution.

[0003] The current production process of needle guards has the following drawbacks: First, the assembled needle guards are prone to separation from the PP / PE guard and the rubber guard during use, which brings inconvenience to the operator; second, the inner hole of the rubber needle guard is small, and it is difficult for the cleaning liquid to enter the inner cavity of the needle guard, resulting in unclean inner cavity of the rubber needle guard; third, the existing rubber needle guard requires a steaming and sulfur extraction process, which wastes energy and pollutes the environment; fourth, in the prior art, the rubber needle guard is siliconized during the siliconization process (emulsified silicone oil is diluted with water), because the emulsified silicone oil and water are not evenly fused, the inner hole of the rubber needle guard is small, and other reasons cause the rubber needle guard to be siliconized inside and outside. Uneven (some places have too much silicone oil, and some places have not been siliconized), the needle cap with more silicone oil is too slippery, which generates vibration during transportation, and the needle cap with more silicone oil slides out of the syringe needle seat, causing the product to be contaminated and unusable; Fifth, due to uneven siliconization in the existing technology, the PP / PE cap and the rubber cap are assembled in the process of deviation, and the inner hole of the rubber cap is not vertical. On the assembly line, the needle on the syringe needle seat will pierce or penetrate the rubber cap body, causing the product to be scrapped; Sixth, the rubber needle cap of the existing technology is prone to white frost, yellowing and other phenomena during storage, posing a safety hazard to users. Summary of the Invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide an integrated two-color needle guard cap. The needle guard cap is an integrated structure and will not separate. It does not need to be cleaned. The local siliconization process is uniform and the needle guard cap will not separate from the syringe needle seat due to transportation or shaking. The thermoplastic elastomer (TPE) is used for injection molding. The thermoplastic elastomer will not show yellowing, white frost and other phenomena, and has a longer service life. In addition, the integrated two-color needle guard cap of the present invention is locally siliconized and siliconized uniformly, and will not vibrate during transportation and cause the needle guard cap to slide out of the needle seat. In addition, since the integrated two-color needle guard cap of the present invention is integrally injection molded, the inner hole of the product is vertical. On the assembly line, the needle on the needle seat will not penetrate or pierce the inner guard cap body, causing the product to be scrapped.

[0005] Another object of the present invention is to provide an integrated two-color needle cap injection molding process to solve the problem of injection molding an integrated two-color needle cap with two layers of different materials.

[0006] The present invention proposes an integrated two-color needle cap, comprising an inner cap and an outer cap, wherein the inner cap is made of thermoplastic elastomer (TPE);

[0007] The outer protective cap is sleeved on the outer side of the inner protective cap, and the outer protective cap and the inner protective cap form an integrated structure;

[0008] An inner cavity channel is provided in the inner protective cap.

[0009] Preferably, the outer protective cap is provided with a plurality of reinforcing ribs, and a circumferential array of the reinforcing ribs is arranged on the circumferential outer surface of the outer protective cap.

[0010] Preferably, the outer protective cap is provided with a hanging platform; the hanging platform is a step-shaped protrusion, which is arranged around the bottom of the truncated cone surface of the outer protective cap;

[0011] The reinforcing rib is arranged at the upper end of the hanging platform and is connected to the hanging platform.

[0012] Preferably, the bottom end surface of the outer protective cap is inwardly concavely provided with an undercut; the undercut is in the shape of an inverted stepped rectangle;

[0013] Preferably, the outer protective cap is provided with a glue feeding matching groove; the glue feeding matching groove is arranged on the top circumference of the outer protective cap.

[0014] Preferably, the inner protective cap is provided with a buckle; the buckle is an annular protrusion structure, and is provided on the inner side wall of the inner cavity channel at one end close to the bottom.

[0015] Preferably, the inner protective cap is provided with a buffer fitting groove; the buffer fitting groove is recessed on the upper end surface of the inner protective cap.

[0016] Preferably, the upper end surface of the inner protective cap is lower than or flush with the upper end surface of the outer protective cap.

[0017] Preferably, the cross section of the outer protective cap is trapezoidal, the cross section of the inner protective cap is trapezoidal, and the outer protective cap and the inner protective cap are interference fit. The outer protective cap and the inner protective cap are integrally injection molded, and the interference fit is optional.

[0018] Optionally, the inner protective cap has a rectangular cross-section and is interference fit with the outer protective cap.

[0019] Preferably, the cross-sectional area of the inner cavity of the inner cavity channel gradually decreases from the bottom to the top, forming a cone-like shape.

[0020] Optionally, the inner cavity channel includes an upper channel, a middle channel and a lower channel; the upper channel is a cylindrical channel, the middle channel is a cone, and the upper end of the middle channel is connected to the lower end of the upper channel, and the lower end of the middle channel is connected to the lower channel.

[0021] Preferably, a buckle groove is concavely provided on the outer side of the lower end surface of the inner protective cap, and a hook ring is provided on the inner side of the outer protective cap near the buckle groove, and the hook ring is hooked in the buckle groove.

[0022] Preferably, an anti-slip groove is provided on the periphery of the outer protective cap; and a sealing ring is provided on the lower inner portion of the inner cavity channel.

[0023] Preferably, a circle of bosses is convexly provided on the periphery of the lower portion of the inner protective cap, a circle of grooves is concavely provided on the inner wall of the outer protective cap, and the bosses are interference fit in the grooves; a receiving reinforcement platform is provided on the periphery lower portion of the outer protective cap.

[0024] Preferably, the thermoplastic elastomer includes the following components in percentage by weight:

[0025]

[0026]

[0027] The gray powder is a color powder mixed with carbon black and titanium dioxide, and the antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

[0028] The present invention also proposes an integrated two-color needle cap injection molding process, comprising the following steps:

[0029] S1, adjust the injection temperature of the injection molding machine nozzle to increase step by step from stage 1, stage 2, stage 3, stage 4;

[0030] S2, injection molding the outer protective cap under the conditions of S1;

[0031] S3, injection molding an inner protective cap in the inner cavity of the outer protective cap;

[0032] S4, performing siliconization and hot air drying treatment on the inner cavity channel of the inner protective cap.

[0033] The present invention has the following technical effects: the inner protective cap and the outer protective cap are injection-molded in a clean room, which has a longer service life and lower cost. Moreover, the process is completed in the clean room and does not require cleaning. The local siliconization is more uniform and can be put into use directly. Thermoplastic elastomer (TPE) is used as the inner protective cap of the one-piece two-color needle guard cap. The inner protective cap will not turn yellow or white, making it safer and more reliable to use.

[0034] Another beneficial effect of the present invention is a one-piece two-color needle cap injection molding process, which solves the problem of injection molding an one-piece two-color needle cap with two layers of different materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the three-dimensional structure of the integrated two-color needle guard according to Example 1 of the present invention;

[0036] Figure 2 This is a stepped cross-sectional view of an integrated two-color needle guard according to Example 1 of the present invention;

[0037] Figure 3 This is a cross-sectional view of an integrated two-color needle guard according to Example 1 of the present invention;

[0038] Figure 4 This is a top view of the one-piece two-color needle guard according to Example 1 of the present invention;

[0039] Figure 5 This is a bottom view of the one-piece two-color needle guard according to Example 1 of the present invention;

[0040] Figure 6 This is a cross-sectional view of an integrated two-color needle guard according to embodiment 2 of the present invention;

[0041] Figure 7 This is a schematic diagram of the three-dimensional structure of the integrated two-color needle guard according to embodiment 2 of the present invention;

[0042] Figure 8 This is a cross-sectional view of an integrated two-color needle guard cap with a buckle groove according to embodiment 2 of the present invention.

[0043] The markings in the figure are as follows: inner protective cap 1; outer protective cap 2; inner cavity channel 3; reinforcing rib 4; hanging platform 5; undercut 6; glue inlet matching groove 7; buckle 8; buffer matching groove 9; upper channel 10; middle channel 11; lower channel 12; buckle groove 13; hook ring 14; anti-slip groove 15; sealing ring 16; boss 17; sealing channel 18. DETAILED DESCRIPTION

[0044] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention.

[0045] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or those recommended by the manufacturer. All reagents or instruments used, if the manufacturer is not specified, are commercially available conventional products.

[0046] Example 1

[0047] like Figures 1 to 5 As shown, the one-piece two-color needle protective cap includes: an inner protective cap 1 and an outer protective cap 2; the material of the inner protective cap 1 is thermoplastic elastomer, and the material of the outer protective cap 2 is PP or PE.

[0048] The outer protective cap 2 is sleeved on the outer surface of the inner protective cap 1, and the outer protective cap 2 and the inner protective cap 1 are formed into an integral structure by injection molding. When the one-piece two-color needle protective cap is pulled out of the needle seat, the PP / PE and the thermoplastic elastomer will not separate. The outer surface of the inner protective cap 1 and the inner surface of the outer protective cap 2 can be perpendicular or tapered, whichever is applicable in this embodiment.

[0049] An inner cavity channel 3 is opened at the center of the lower end surface of the inner protective cap 1. The inner cavity channel 3 is a cavity for accommodating the injection needle. When the one-piece two-color needle protective cap is inserted into the needle seat, the injection needle is prevented from being contaminated, bruised or hurting people before use in the inner cavity channel 3.

[0050] In a preferred further implementation manner of this embodiment, the outer protective cap 2 is provided with reinforcing ribs 4, the number of the reinforcing ribs 4 is at least 2, and the reinforcing ribs 4 are arranged in a vertical strip-shaped circular array on the outer circumferential surface of the outer protective cap 2; the reinforcing ribs 4 can enhance the strength of the outer protective cap 2, and the concave and convex shape formed with the outer protective cap 2 can also reduce the production materials, and can also play an anti-slip role during use.

[0051] In a preferred further embodiment of this embodiment, the outer protective cap 2 is provided with a hanging platform 5; the hanging platform 5 is a step-shaped protrusion, which is arranged around the bottom of the truncated cone surface of the outer protective cap 2;

[0052] The reinforcing rib 4 is arranged at the upper end of the hanging platform 5 and is connected to the hanging platform 5. The hanging platform 5 acts as a fulcrum when the injection needle is pulled out, making it convenient to pull out the injection needle.

[0053] In a preferred further embodiment of this embodiment, the bottom end surface of the outer protective cap 2 is provided with an inwardly concave undercut 6; the undercut 6 is an inverted stepped rectangular arrangement;

[0054] The undercut 6 is used to lock the one-piece two-color needle guard cap to the movable mold during the mold opening process after injection molding, so as to avoid adhesion to the fixed mold and mold compression, which may damage the mold and cause production suspension.

[0055] In a preferred further implementation manner of this embodiment, the outer protective cap 2 is provided with a glue inlet matching groove 7; the glue inlet matching groove 7 is arranged on the top circumference of the outer protective cap 2, and the glue inlet matching groove 7 cooperates with the injection molding machine to inject PP / PE raw materials inward through the injection molding cylinder and plays a buffering role.

[0056] In a preferred further implementation manner of this embodiment, the inner protective cap 1 is provided with a buckle 8; the buckle 8 is an annular protrusion structure, which is arranged on the inner side wall of the inner cavity channel 3 near the bottom end; the number of the buckles 8 can be one or more, and can be arranged continuously or intermittently in the inner cavity channel 3, both of which can be implemented in this embodiment.

[0057] The buckle 8 is used to fix the connection with the needle seat. When the one-piece two-color needle guard cap is inserted into the needle seat, the buckle 8 buckles the needle seat and further holds the needle seat tightly, so that the one-piece two-color needle guard cap is fixed on the needle seat. During transportation or shaking, the one-piece two-color needle guard cap will not separate from the needle seat.

[0058] In a preferred further implementation manner of this embodiment, the inner protective cap 1 is provided with a buffer fitting groove 9; the buffer fitting groove 9 is recessed in the upper end surface of the inner protective cap 1, and the buffer fitting groove 9 cooperates with the injection molding machine to inject the thermoplastic elastomer (TPE) raw material inward through the injection cylinder, while also playing a buffering role, so that the thermoplastic elastomer raw material will not be completely poured out at one time, thereby improving the injection molding efficiency.

[0059] In a preferred further implementation manner of this embodiment, the upper end surface of the inner protective cap 1 is lower than or flush with the upper end surface of the outer protective cap 2, and the buffer matching groove forms an expanded step surface with the upper end surface of the inner protective cap and the upper end surface of the outer protective cap. When the injection molding machine is injecting, the step surface can serve as a buffer zone, so that the injection molding process can be carried out in stages, thereby improving the injection molding efficiency and reducing the cost loss caused by excessive injection molding.

[0060] In a preferred further implementation of this embodiment, the outer protective cap 2 is a hollow truncated cone structure with an isosceles trapezoidal cross section, and the inner protective cap 1 is an inverted trapezoid with a trapezoidal cross section, and the outer protective cap and the inner protective cap are interference fit.

[0061] The inner protective cap 1 may also be a cylinder with a rectangular cross section and has an interference fit with the outer protective cap 2 .

[0062] Preparation of thermoplastic elastomer, the formula table is as follows:

[0063] Raw material name Mass fraction% Manufacturing Company (Origin) model Hydrogenated styrene-butadiene block copolymer (HSBC) 40 KRATON / USA G1651 Polypropylene 10 LCY / Taiwan ST866M Medical lime oil 44 EXXON / USA PRIMOL 352 Gray powder 0.2 Yunde / China 183201 antioxidants 0.2 BASF / Germany Irganox 1010 calcium carbonate 5.6 Guangyuan / China HX2800

[0064] The above raw materials were kneaded at 100° C. for 3 minutes and processed using a pelletizer to obtain a pelletized thermoplastic elastomer.

[0065] The method for preparing the above-mentioned one-piece two-color needle cap is as follows:

[0066] Option 1:

[0067] Step 1: Place PP / PE and thermoplastic elastomer (TPE) raw materials in injection cylinders A and B in a multi-material two-color injection molding machine, respectively. Use injection cylinder A to inject the PP / PE outer cap first. The injection temperatures are 165-190°C for the first stage, 180-190°C for the second stage, 195°C for the third stage, and 205°C for the fourth stage. The nozzle temperature is 210°C, the mold manifold temperature is 210°C, the hot nozzle temperature is 215°C, the injection pressure is 65-75MPa, and the injection time is 2 seconds.

[0068] Step 2: The multi-material two-color injection molding machine opens the mold, rotates the machine table, and then closes the mold; uses syringe B to inject the thermoplastic elastomer inner cap into the upper cavity, so that the thermoplastic elastomer (TPE) and PP / PE are tightly interlocked into one. The injection temperatures are 160-190°C for the first stage, 180-200°C for the second stage, 190-200°C for the third stage, and 195-205°C for the fourth stage. The nozzle temperature is 205°C, the mold manifold temperature is 205-215°C, the hot nozzle temperature is 210-230°C, the injection pressure is 55-70MPa, and the injection time is 2 seconds.

[0069] While injecting thermoplastic elastomer (TPE), syringe A on the multi-material two-color injection molding machine is injecting PP / PE.

[0070] Step 3: The multi-material two-color injection molding machine opens the mold, rotates the machine table, and releases the one-piece two-color needle cap product in the PP / PE injection area. The mold is then closed again, and the thermoplastic elastomer (TPE) and PP / PE are injected simultaneously. This process is repeated to achieve automated production.

[0071] Option 2:

[0072] The PP / PE outer cap is first injection molded on a single-color machine. Next, the PP / PE outer cap is loaded into a thermoplastic elastomer mold on another single-color machine, and then a thermoplastic elastomer (TPE) inner cap is injection molded to obtain a complete one-piece two-color needle cap product.

[0073] Testing standards and conclusions for the one-piece two-color needle cap prepared in Scheme 1:

[0074]

[0075] In summary, the one-piece two-color needle guard cap prepared by the present invention meets industry standards in all performance tests. The inner guard cap and the outer guard cap are injection molded in a clean room, which has a longer service life and lower cost. Moreover, the process is completed in the clean room and can be put into use without cleaning. Based on the use of thermoplastic elastomer (TPE) as the inner guard cap of the one-piece two-color needle guard cap, the inner guard cap will not turn yellow or white, and is safer and more reliable to use. Moreover, its simple and three-dimensional structural design is more practical and more convenient to use.

[0076] Example 2

[0077] There are many problems with rubber needle guards in the prior art. The following are the problems of the prior art:

[0078] 1: Rubber needle caps are prone to white frost and yellowing during storage, posing a safety hazard to users;

[0079] 2: The rubber needle cap is a whole piece of vulcanized needle cap film, which is formed into a needle cap after punching. During the large-scale punching process, the rubber will produce rubber threads and rubber scraps, and the rubber plug and rubber scraps will fall and adhere to various parts of the needle cap (randomly fall, and may also fall into secondary small holes). The top hole of the inner cavity of the rubber needle cap is small, and it is difficult for the cleaning liquid to enter the inner cavity of the needle cap, resulting in unclean inner cavity of the rubber needle cap; due to defects in the structural design of the existing technology product, the siliconization is uneven, and the PP / PE cap and the rubber cap are assembled during assembly. The inner hole of the rubber cap is not vertical, and the needle on the needle seat will pierce or penetrate the rubber cap body on the assembly line, resulting in product scrapping.

[0080] 3: The existing technology of combined protective cap production process is complicated, the product qualification rate is low, the production cost is high, the pollution is serious, and the market promotion is slow.

[0081] The present invention provides a new integrated two-color needle guard cap: Figure 6 like Figure 8 As shown, it includes an inner protective cap 1 and an outer protective cap 2. The inner protective cap 1 is made of a thermoplastic elastomer; the outer protective cap 2 is mounted on the outer surface of the inner protective cap 1, and the outer protective cap 2 and the inner protective cap 1 form an integral structure; the inner protective cap 1 defines an inner cavity 3. The cross-sectional area of the cavity within the inner cavity 3 gradually decreases from the bottom to the top, forming a cone-like shape. The inner protective cap 1 and the outer protective cap 2 form a double-layer protective cap, and the inner protective cap is made of a thermoplastic elastomer. The inner protective cap defines an inner cavity, and the needle body is protected within the inner cavity.

[0082] The material of the outer protective cap can be PP / PE, and the material of the inner protective cap can be thermoplastic elastomer; this forms a double-layer protective cap with different materials. The inner wall of the outer protective cap and the inner protective cap thermoplastic elastomer are precisely formed into one through injection molding; when in use, not only the inner protective cap of the inner layer can seal and protect it, but the outer protective cap of the outer layer will not cause misoperation due to the operator pulling out the cap. The existing combined protective caps need to be cleaned before use, but the double-layer one-piece molded needle cap of the present invention, which is injection molded in a clean room, does not need to be cleaned and can be put into use. During storage, the inner protective cap of the thermoplastic elastomer will not turn yellow or white, and the needle protective cap is safer and more reliable to use;

[0083] After the integrated two-color needle guard of the present invention is installed and sterilized on the assembly line at high temperature, the thermoplastic elastomer inner guard cap and the PP / PE hard plastic outer guard cap tightly interlock to form a one-piece structure. The thermoplastic elastomer inner guard cap body is restrained by the PP / PE hard plastic guard cap body, preventing deformation. This allows the TPE inner guard cap to fit snugly and tightly to the syringe needle, preventing leakage. The integrated structural design significantly reduces raw material and production costs. The integrated double-layer outer and inner guard structure solves the industry-wide problem of low cleaning, siliconization, and packaging efficiency of split needle guards. It also meets the requirements of high-speed packaging lines, preventing the needle from puncturing the needle hub during assembly.

[0084] In a preferred further embodiment of this embodiment, the cross-sectional area of the inner cavity of the inner cavity channel 3 gradually decreases from the bottom to the top, forming a cone-like shape. This configuration is more consistent with the structure of the syringe needle and fits more closely, snugly and tightly on the syringe needle.

[0085] In an optional further implementation manner of this embodiment, the inner cavity channel includes an upper channel 10, a middle channel 11 and a lower channel 12; the upper channel 10 is a cylindrical channel, the middle channel 11 is a cone, and the upper end of the middle channel 11 is connected to the lower end of the upper channel, and the lower end of the middle channel 11 is connected to the lower channel 12.

[0086] In a preferred further embodiment of this embodiment, the outer side of the lower end surface of the inner protective cap 1 is provided with a buckle groove 13, and the inner side of the outer protective cap 2 is provided with a hook ring 14 near the buckle groove 13, and the hook ring 14 is hooked in the buckle groove 13. This arrangement enhances the stability of the connection between the outer protective cap 2 and the inner protective cap 1.

[0087] In this embodiment, the outer protective cap 2 is preferably provided with an anti-slip groove 15; the anti-slip groove 15 allows air inside the outer protective cap 2 to be discharged; a sealing channel 18 is provided at the lower portion of the inner cavity channel, and a sealing ring 16 is provided at the lower portion of the sealing channel to enhance the sealing performance when installed on the injection needle. The sealing ring 16 further enhances the sealing performance.

[0088] In this embodiment, the inner protective cap 1 preferably has a circle of bosses 17 convexly provided on the periphery of the lower portion, the outer protective cap has a circle of grooves concavely provided on the inner wall, and the bosses are interference fit in the grooves; and a receiving reinforcement platform is provided on the periphery lower portion of the outer protective cap.

[0089] In this embodiment, preferably, adjustment ribs are provided on the periphery of the outer protective cap; there can be multiple adjustment ribs, and the number is not limited. The adjustment ribs not only strengthen the stability of the entire structure, but also play a role in adjusting the weight of the one-piece two-color needle guard cap itself; the weight of the one-piece two-color needle guard cap itself can be adjusted by adjusting the depth and length of the ribs; the adjustment ribs can also play an anti-slip role. In order to make the best use of the existing production line and save costs, adjustment ribs are provided. Because the existing production line needle guard cap filling and assembly lines have very high requirements for the outer diameter and weight of the needle guard cap, and since the specific gravity of thermoplastic elastomer (TPE) is lighter than that of rubber, this problem can be solved by adjusting the number of ribs provided when the weight and outer circle remain unchanged. This greatly saves costs.

[0090] Preparation of thermoplastic elastomer, the formula table is as follows:

[0091]

[0092]

[0093] Stir HSBC-->Medical calcite oil-->Stir for 15 minutes-->Add the remaining ingredients-->Continue stirring for 10 minutes before extrusion and granulation.

[0094] The method for preparing the above-mentioned one-piece two-color needle cap is as follows:

[0095] Option 1:

[0096] Step 1: Place PP / PE and thermoplastic elastomer (TPE) raw materials in injection cylinders A and B in a multi-material two-color injection molding machine, respectively. Use injection cylinder A to inject the PP / PE outer cap first. The injection temperatures are 165-190°C for the first stage, 180-190°C for the second stage, 195°C for the third stage, and 205°C for the fourth stage. The nozzle temperature is 210°C, the mold manifold temperature is 210°C, the hot nozzle temperature is 215°C, the injection pressure is 65-75MPa, and the injection time is 2 seconds.

[0097] Step 2: The multi-material two-color injection molding machine opens the mold, rotates the machine table, and then closes the mold; uses syringe B to inject the thermoplastic elastomer inner cap into the upper cavity, so that the thermoplastic elastomer (TPE) and PP / PE are tightly interlocked into one. The injection temperatures are 160-190°C for the first stage, 180-200°C for the second stage, 190-200°C for the third stage, and 195-205°C for the fourth stage. The nozzle temperature is 205°C, the mold manifold temperature is 205-215°C, the hot nozzle temperature is 210-230°C, the injection pressure is 55-70MPa, and the injection time is 2 seconds.

[0098] While injecting thermoplastic elastomer (TPE), syringe A on the multi-material two-color injection molding machine is injecting PP / PE.

[0099] Step 3: The multi-material two-color injection molding machine opens the mold, rotates the machine table, and releases the one-piece two-color needle cap product in the PP / PE injection area. The mold is then closed again, and the thermoplastic elastomer (TPE) and PP / PE are injected simultaneously. This process is repeated to achieve automated production.

[0100] Option 2:

[0101] The PP / PE outer cap is first injection molded on a single-color machine. Next, the PP / PE outer cap is loaded into a thermoplastic elastomer mold on another single-color machine, and then a thermoplastic elastomer (TPE) inner cap is injection molded to obtain a complete one-piece two-color needle cap product.

[0102] Testing standards and conclusions for the one-piece two-color needle cap prepared in Scheme 1:

[0103]

[0104] In summary, the one-piece two-color needle guard cap prepared by the present invention meets industry standards in all performance tests. The inner guard cap and the outer guard cap are injection molded in a clean room, which has a longer service life and lower cost. Moreover, the process is completed in the clean room and can be put into use without cleaning. Based on the use of thermoplastic elastomer (TPE) as the inner guard cap of the one-piece two-color needle guard cap, the inner guard cap will not turn yellow or white, and is safer and more reliable to use. Moreover, its simple and three-dimensional structural design is more practical and more convenient to use.

[0105] Example 3:

[0106] A one-piece two-color needle cap injection molding process, characterized by:

[0107] S1, adjust the injection temperature of the injection molding machine nozzle to increase step by step from stage 1, stage 2, stage 3, stage 4;

[0108] S2, injection molding the outer protective cap under the conditions of S1;

[0109] S3, injection molding an inner protective cap in the inner cavity of the outer protective cap;

[0110] S4, performing siliconization and hot air drying treatment on the inner cavity channel of the inner protective cap.

[0111] S1: On a two-color injection molding machine, the PP / PE and thermoplastic elastomer (TPE) raw materials are placed in two storage barrels in the multi-material two-color injection molding machine respectively. The PP / PE hard rubber outer cap is first injected with one syringe. The injection temperature of the injection molding machine nozzle is adjusted to the first temperature, the second temperature, the third temperature, and the fourth temperature. The nozzle temperature is increased step by step. The temperature of the mold manifold and the nozzle are adjusted to appropriate temperatures. The injection pressure is injected.

[0112] S2: On the same two-color injection molding machine, the two-color injection molding machine opens the mold, rotates the machine table, and then closes the mold to inject the inner protective cap (thermoplastic elastomer TPE, so that the thermoplastic elastomer TPE inner protective cap body and the PP / PE hard rubber outer protective cap body are tightly bitten into one; while the thermoplastic elastomer TPE inner protective cap body is being injected, another nozzle on the two-color injection molding machine is injecting the PP / PE hard rubber outer protective cap, wherein the injection temperature of the injection molding machine nozzle is respectively the first temperature, the second temperature, the third temperature, and the fourth temperature, and the temperature at the nozzle is gradually increased;

[0113] S3: On the same two-color injection molding machine, the two-color injection molding machine opens the mold, rotates the machine table, and pushes out the integral needle cap product in the PP / PE hard rubber outer cap injection area. The mold is closed again, and the PP / PE hard rubber outer cap and the thermoplastic elastomer TPE soft rubber inner cap are injected at the same time. Repeat steps 2 and 3 to form automated production.

[0114] S4: siliconizing and hot air drying the inner cavity of the inner protective cap.

[0115] The present invention can be processed and formed in a C+A grade environment, has a simple process flow, is highly efficient, requires no cleaning, and has no chip dropping during puncture.

[0116] Although the present invention has been disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. An integrated two-color needle guard, characterized in that: It includes an inner protective cap and an outer protective cap, wherein the inner protective cap is made of thermoplastic elastomer; The outer protective cap is sleeved outside the inner protective cap, and the outer protective cap and the inner protective cap form an integrated structure; An inner cavity channel is provided in the inner protective cap; The outer protective cap is provided with a plurality of reinforcing ribs, and the reinforcing ribs are arranged in a circumferential array on the outer circumferential surface of the outer protective cap; The outer protective cap is provided with a hanging platform; The hanging platform is a step-shaped protrusion, which is arranged around the bottom of the truncated cone surface of the outer protective cap; The reinforcing rib is arranged at the upper end of the hanging platform and is connected to the hanging platform; The reinforcing ribs and the outer protective cap form a concave-convex shape; The bottom end surface of the outer protective cap is inwardly concave and provided with an undercut; The undercut is arranged in an inverted stepped rectangular shape; The outer protective cap is provided with a glue feeding matching groove; The glue inlet matching groove is arranged on the top circumference of the outer protective cap; The inner protective cap is provided with a buckle; The buckle is an annular protrusion structure, which is arranged on the inner side wall of the inner cavity channel near the bottom end; The buckle is used to fix the needle seat. When the one-piece two-color needle guard is inserted into the needle seat, the buckle buckles the needle seat and further holds the needle seat tightly, so that the one-piece two-color needle guard is fixed on the needle seat. During transportation or shaking, the one-piece two-color needle guard will not separate from the needle seat. The inner protective cap is provided with a buffer fitting groove; The buffer matching groove is recessed on the upper end surface of the inner protective cap; The upper end surface of the inner protective cap is lower than or flush with the upper end surface of the outer protective cap; the buffer matching groove and the upper end surface of the inner protective cap and the upper end surface of the outer protective cap form an expanded step surface; the step surface can serve as a buffer zone, so that the injection molding process can be carried out in stages. The cross section of the outer protective cap is trapezoidal, the cross section of the inner protective cap is trapezoidal or rectangular, and the outer protective cap and the inner protective cap are interference fit; The cross-sectional area of the cavity inside the inner cavity channel gradually decreases from the bottom to the top, forming a cone-like shape; The inner cavity channel includes an upper channel, a middle channel and a lower channel; the upper channel is a cylindrical channel, the middle channel is a cone, and the upper end of the middle channel is connected to the lower end of the upper channel, and the lower end of the middle channel is connected to the lower channel; The outer side of the lower end surface of the inner protective cap is provided with a buckle groove inwardly, and the inner side of the outer protective cap is provided with a hook ring near the buckle groove, and the hook ring is hooked in the buckle groove; the outer periphery of the lower part of the inner protective cap is provided with a circle of bosses, and the inner wall of the outer protective cap is provided with a circle of grooves, and the bosses are interference-fitted in the grooves; the outer periphery of the outer protective cap is provided with a receiving reinforcement platform; The outer periphery of the outer protective cap is provided with an anti-slip groove; the lower part of the inner cavity channel is provided with a sealing ring; The outer protective cap is a hollow truncated cone structure with an isosceles trapezoidal cross section, and the inner protective cap is an inverted trapezoid with a trapezoidal cross section. The outer protective cap and the inner protective cap are interference fit.

2. The one-piece two-color needle guard according to claim 1, characterized in that: Thermoplastic elastomers include the following components in percentage by mass: The gray powder is a toner mixed with carbon black and titanium dioxide, and the antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

3. An integrated two-color needle cap injection molding process, characterized by: The invention comprises the one-piece two-color needle guard as claimed in claim 1 or claim 2, and further comprises the following process: S1. Adjust the injection molding temperature of the injection molding machine nozzle to gradually increase from stage 1, stage 2, stage 3, and stage 4. Specifically, on a two-color injection molding machine, place the PP / PE and thermoplastic elastomer (TPE) raw materials in two storage barrels of the multi-material two-color injection molding machine, respectively. Use one syringe to first inject the PP / PE hard rubber outer protective cap. The injection molding machine nozzle injection temperature is adjusted to stage 1, stage 2, stage 3, and stage 4, and the nozzle temperature is gradually increased. The mold manifold temperature and hot nozzle temperature are adjusted to appropriate levels. Injection molding is performed under the following injection pressure: the injection temperature is 165-190°C for stage 1, 180-190°C for stage 2, 195°C for stage 3, and 205°C for stage 4. The nozzle temperature is 210°C, the mold manifold temperature is 210°C, the hot nozzle temperature is 215°C, the injection pressure is 65-75MPa, and the injection time is 2 seconds. S2, injection molding the outer protective cap under the conditions of S1; specifically: on the same two-color injection molding machine, the two-color injection molding machine opens the mold, rotates the machine table, and then closes the mold to inject the inner protective cap (thermoplastic elastomer TPE, so that the thermoplastic elastomer TPE inner protective cap body and the PP / PE hard rubber outer protective cap body are tightly bitten into one; while the thermoplastic elastomer TPE inner protective cap body is being injected, another nozzle on the two-color injection molding machine is injecting the PP / PE hard rubber outer protective cap, wherein the injection temperature of the injection molding machine nozzle is respectively the first stage temperature, the second stage temperature, the third stage temperature, and the fourth stage temperature, and the temperature at the nozzle is gradually increased; wherein: the injection temperature is respectively 160-190℃ for the first stage, 180-200℃ for the second stage, 190-200℃ for the third stage, and 195-205℃ for the fourth stage, and the temperature at the nozzle is 205℃, Mold manifold temperature 205-215℃, nozzle temperature 210-230℃, injection pressure 55-70MPa, injection time 2 seconds); S3, injection molding the inner protective cap into the inner cavity of the outer protective cap; specifically, on the same two-color injection molding machine, the two-color injection molding machine opens the mold, rotates the machine table, and pushes out the integral needle protective cap product in the PP / PE hard rubber outer protective cap injection area. The mold is closed again, and the PP / PE hard rubber outer protective cap and the thermoplastic elastomer TPE soft rubber inner protective cap are injected simultaneously. Repeat steps 2 and 3 to form automated production. S4, performing siliconization and hot air drying treatment on the inner cavity channel of the inner protective cap.

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