Three-layer co-extrusion blow-molded light-proof medicine bottle

Abstract

The present application relates to the technical field of light-proof bottles, in particular to a three-layer co-extrusion blow-molded light-proof medical bottle. The light-proof bottle comprises a structure appearance layer, a dark light-proof layer and an internal clean layer. The structure appearance layer, the dark light-proof layer and the internal clean layer are sequentially arranged from outside to inside, and the adjacent layers are directly fused and integrated into an integral structure. The internal clean layer is made of pure polyolefin material, which does not contain any sunscreen and functional additives. The dark light-proof layer is completely wrapped between the structure appearance layer and the internal clean layer. The content of the medicine bottle only contacts with the internal clean layer, and the sunscreen ingredients will not migrate to the content during the storage period. Compared with the conventional brown medicine bottle design, the structure appearance layer does not need to be dark, which ensures the appearance.

Description

Technical Field

[0001] This invention relates to the field of light-proof bottle technology, and in particular to a three-layer co-extrusion blown pharmaceutical light-proof bottle. Background Technology

[0002] Pharmaceutical light-proof packaging has the core function of blocking light radiation in specific wavelengths. Currently, pharmaceutical light-proof plastic bottles that have achieved large-scale application mainly adopt single-layer coloring schemes or double-layer co-extrusion schemes. The single-layer coloring scheme involves directly adding a certain proportion of light-blocking agent masterbatch to a polyolefin substrate, and then extruding and blow molding it into a homogeneous dark-colored bottle body. The double-layer co-extrusion scheme involves melting the inner pure material and the outer material containing light-blocking agent in two extruders respectively, and then merging them in the die head to form a two-layer composite bottle wall that is clean inside and light-proof outside.

[0003] The above two types of solutions still have the following technical problems in long-term use: 1. Absolute physical isolation between the opaque agent and the drug contents cannot be achieved. In the single-layer solution, the opaque agent particles are directly exposed on the inner wall surface of the bottle. Although the double-layer solution restricts the opaque agent to the outer layer, there is still a risk that the outer layer material will roll inward or mix in at the bottle mouth end face, parting line and wall thickness fluctuation area. Direct contact between the drug and the opaque agent will lead to the dissolution index exceeding the standard. 2. When laser coding or ink spraying is performed directly on the dark bottle surface, the contrast between the characters and the background color is low, which affects the scanning and reading success rate of the automated production line. If additional labels are pasted, they are prone to peeling off due to the curvature of the bottle surface. Summary of the Invention

[0004] The purpose of this invention is to address the problems existing in the background art by proposing a three-layer co-extrusion blown pharmaceutical light-proof bottle.

[0005] The technical solution of this invention is a three-layer co-extrusion blown pharmaceutical light-proof bottle, comprising: The light-proof bottle includes a structural outer layer, a dark light-proof layer, and an inner clean layer. The structural outer layer, the dark light-proof layer, and the inner clean layer are arranged sequentially from the outside to the inside, and adjacent layers are directly fused together to form a single structure.

[0006] Preferably, the surface of the structural appearance layer is coated with an irreversible temperature-indicating coating.

[0007] Preferably, the surface of the light-proof bottle has an annular label groove for attaching labels.

[0008] Preferably, the surface of the light-proof bottle is provided with reinforcing ribs, which are distributed in a grid pattern on the outer surface of the light-proof bottle, and the reinforcing ribs are integrally extruded with the light-proof bottle.

[0009] Preferably, the thickness of the internal cleanroom layer is 0.10-0.25 mm; the thickness of the dark light-blocking layer is 0.15-0.35 mm; and the thickness of the structural appearance layer is 0.50-1.20 mm.

[0010] Preferably, both the structural exterior layer and the internal cleanroom layer are made of polyolefin materials.

[0011] Preferably, the material of the dark light-blocking layer is a polyolefin material that includes a light-blocking agent.

[0012] Compared with the prior art, the present invention has the following beneficial technical effects: 1. The internal clean layer is made of pure polyolefin material, which does not contain any light-blocking agents or functional additives. This ensures that the dark light-blocking layer is completely wrapped between the structural appearance layer and the internal clean layer. The contents of the medicine bottle only come into contact with the internal clean layer, and the light-blocking agent will not migrate to the contents during the storage period. In addition, compared with the conventional brown medicine bottle design, its structural appearance layer does not need to be dark, ensuring its aesthetics. 2. The outer layer of the bottle retains the original printability and coding adaptability of polyolefin material, while the dark light-blocking layer gives the bottle a high light-blocking rate. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of Embodiment 1; Figure 2 This is a schematic diagram of the layered structure of the light-proof bottle in this invention; Figure 3 This is a schematic diagram of the structure of Embodiment 2; Figure 4 This is a schematic diagram of the structure of Embodiment 3.

[0014] Reference numerals: 1. Light-proof bottle; 101. Structural appearance layer; 102. Dark light-proof layer; 103. Internal clean layer; 1001. Circular label groove; 2. Reinforcing rib. Detailed Implementation

[0015] Example 1; as Figure 1 and Figure 2 As shown in this embodiment, a three-layer co-extrusion blown pharmaceutical light-proof bottle includes a light-proof bottle 1. The light-proof bottle 1 includes a structural appearance layer 101, a dark light-proof layer 102, and an inner clean layer 103. The structural appearance layer 101, the dark light-proof layer 102, and the inner clean layer 103 are arranged sequentially from the outside to the inside, and adjacent layers are directly fused together to form an integral structure. The thickness of the inner clean layer 103 is 0.10-0.25 mm; the thickness of the dark light-proof layer 102 is 0.15-0.35 mm; and the thickness of the structural appearance layer 101 is 0.50-1.20 mm. The materials of the structural appearance layer 101 and the inner clean layer 103 are both polyolefin materials; the material of the dark light-proof layer 102 is a polyolefin material including a light-blocking agent.

[0016] In this embodiment, the light-proof bottle 1 adopts a three-layer composite structure consisting of an outer structural layer 101, a dark light-proof layer 102, and an inner clean layer 103. It should be noted that these three different material layers are preferably extruded by three-layer co-extrusion. During the extrusion blow molding process, the materials are joined together in a high-temperature molten state, thereby solidifying into a whole bottle body.

[0017] After the liquid medicine is filled into the bottle, the innermost inner clean layer 103 comes into direct contact with the liquid medicine. It should be noted that the inner clean layer 103 is a pure pharmaceutical-grade polyolefin material without any added light-blocking agents or functional coloring masterbatches. The inner clean layer 103 forms an isolation barrier between the liquid medicine and the functional additives. During the shelf life of the medicine, the inner clean layer 103, through its stable chemical inertness, eliminates the risk of light-blocking agent components contained in the dark light-blocking layer 102 migrating or dissolving into the liquid medicine, thereby ensuring that the contents meet the safety standards for compatibility of pharmaceutical packaging materials.

[0018] When ambient light shines on the surface of the light-proof bottle 1, the light first penetrates the structural outer layer 101, which is also made of pure polyolefin material. The light can pass through this layer and reach the dark light-proof layer 102. The dark light-proof layer 102 is uniformly covered on the outer wall of the inner clean layer 103 and extends to the bottom of the bottle and the threaded area of ​​the bottle mouth. The material of the dark light-proof layer 102 is uniformly mixed with light-shielding agent particles. The light-shielding agent particles have an absorption and scattering effect on light. By setting up a progressive physical layered interception structure, the light-proof bottle 1 can effectively achieve high light protection for the contents, thereby avoiding the degradation of the active ingredients of the medicine due to photochemical reactions.

[0019] To ensure applicability across different specifications and material systems, various sizes of light-proof bottles were prepared based on a fixed wall thickness ratio. For example, in an HDPE system sample prepared for 100mL oral solid pharmaceutical packaging, the inner clean layer 103 has a thickness of 0.15mm, the dark light-proof layer 102 has a thickness of 0.225mm, and the structural appearance layer 101 has a thickness of 0.60mm. The thickness ratio of the three layers precisely meets the design benchmark of 1:1.5:4. In 500mL oral liquid pharmaceutical HDPE bottles and 5000mL large-capacity HDPE raw material bottles, the thicknesses of the inner clean layer 103 are selected as 0.20mm and 0.25mm, respectively, and the corresponding thickness of the dark light-proof layer 102 is 0.30mm. The thickness of the three layers is 0.375 mm, while the thickness of the structural appearance layer 101 is 0.90 mm and 1.125 mm, respectively. The thickness ratio of the three layers in these two specifications is maintained within the range of 1:1.5:4.5. In the PP system samples, the thickness of the internal clean layer 103 of the 1000 mL oral liquid bottle and the 5000 mL raw material bottle is also set to 0.20 mm and 0.25 mm, respectively. The thickness of the dark light-blocking layer 102 is 0.30 mm and 0.375 mm, respectively. The thickness of the structural appearance layer 101 is 0.90 mm and 1.125 mm, respectively. The thickness ratio of the three layers is consistent with the aforementioned HDPE large-size products, which has a numerical relationship of 1:1.5:4.5. The above samples cover a variety of mainstream pharmaceutical polyolefin substrates.

[0020] Additionally, it should be noted that an irreversible temperature-indicating coating is applied to the surface of the structural appearance layer 101. This coating can be applied locally by spraying. When the temperature exceeds the limit, the coating undergoes thermal decomposition, oxidation, solid-phase reaction, and other chemical changes, resulting in permanent discoloration. Furthermore, a color card can be printed on the label film of the bottle. By observing the color of the coating and its corresponding color on the color card, it can be determined whether the ambient temperature of the bottle storage environment exceeds the set threshold.

[0021] Example 2; as Figure 3 As shown in the figure, the three-layer co-extrusion blown pharmaceutical light-proof bottle proposed in this embodiment has an annular label groove 1001 for attaching labels on the surface of the light-proof bottle 1 compared to the first embodiment.

[0022] In this embodiment, in the prior art, when self-adhesive labels are directly pasted on the smooth curved surface, the label is prone to falling off, which affects the scanning and recognition rate of the drug electronic supervision code. In the working process of this embodiment, the annular label groove 1001 is recessed inward to a certain depth. When the self-adhesive label is pasted into the annular label groove 1001, the edge of the label is limited by the groove wall, which greatly reduces the probability of being scratched and lifted during circulation.

[0023] Example 3; as Figure 4As shown in the figure, the three-layer co-extrusion blown pharmaceutical light-proof bottle proposed in this embodiment has a reinforcing rib 2 on the surface of the light-proof bottle 1 compared with the first embodiment. The reinforcing rib 2 is distributed in a grid pattern on the outer surface of the light-proof bottle 1, and the reinforcing rib 2 and the light-proof bottle 1 are integrally extruded and formed.

[0024] In this embodiment, the reinforcing ribs 2 are distributed in a grid pattern and integrally extruded with the light-shielding bottle 1. It should be noted that in the application of large-capacity light-shielding bottles 1, such as raw material packaging bottles with a volume of more than 1000 ml, the hydrostatic pressure after filling the liquid and the gripping force during handling will generate a high bending moment load on the bottle wall. In the interlaced area where the reinforcing ribs 2 are provided, the structural strength of the structural appearance layer 101 is increased. When the user's palm grips the middle of the bottle body for pouring, the radial pressure applied by the fingers first acts on the raised surface of the reinforcing ribs 2, avoiding the inward collapse of the structural appearance layer 101 due to stress concentration. After the inward collapse occurs, it will directly squeeze the dark light-shielding layer 102 in the middle, which will easily cause the light-shielding efficiency of this area to drop instantly. At the same time, the grid-distributed reinforcing ribs 2 can improve the stacking resistance of the entire light-shielding bottle 1 during the stacking and transportation process without significantly increasing the weight of the bottle body material, so that the bottle body is not prone to bulging and deformation due to long-term load.

[0025] Although the outer layer 101, the dark light-shielding layer 102, and the inner clean layer 103 are an integral structure, the shrinkage rates of each layer are inherently different during the cooling and shaping process. During the repeated thermal expansion and contraction of the light-shielding bottle 1 after blow molding, there will be slight deviations in the shrinkage of each layer. In the flat parts of the bottle wall without reinforcement, the above-mentioned shear stress can only be borne by the welded interface on both sides of the dark light-shielding layer 102 and evenly distributed along the circumference. When the size of the light-shielding bottle 1 is large or the temperature difference of the storage environment is large, it is easy to cause silver streaks or stress whitening at the interface at the microscale. The grid distribution of the reinforcing ribs 2 can interrupt the continuity of stress free transmission on the smooth cylindrical surface. The staggered nodes of the reinforcing ribs 2 introduce several anchoring points on the curved surface of the bottle wall. These nodes suppress the tendency of relative slippage between layers.

[0026] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A three-layer co-extrusion blown pharmaceutical light-proof bottle, characterized in that, include: The light-proof bottle (1) includes a structural appearance layer (101), a dark light-proof layer (102), and an inner clean layer (103). The structural appearance layer (101), the dark light-proof layer (102), and the inner clean layer (103) are arranged sequentially from the outside to the inside, and adjacent layers are directly fused together to form an integral structure.

2. The three-layer co-extrusion blown pharmaceutical light-proof bottle according to claim 1, characterized in that, The surface of the structural appearance layer (101) is coated with an irreversible temperature-indicating coating.

3. The three-layer co-extrusion blown pharmaceutical light-proof bottle according to claim 1, characterized in that, The surface of the light-proof bottle (1) has an annular label groove (1001) for attaching labels.

4. A three-layer co-extrusion blown pharmaceutical light-proof bottle according to claim 1, characterized in that, The surface of the light-proof bottle (1) is provided with reinforcing ribs (2). The reinforcing ribs (2) are distributed in a grid pattern on the outer surface of the light-proof bottle (1), and the reinforcing ribs (2) are integrally extruded with the light-proof bottle (1).

5. A three-layer co-extrusion blown pharmaceutical light-proof bottle according to claim 1, characterized in that, The thickness of the internal cleanroom layer (103) is 0.10-0.25 mm; the thickness of the dark light-blocking layer (102) is 0.15-0.35 mm; and the thickness of the structural appearance layer (101) is 0.50-1.20 mm.

6. A three-layer co-extrusion blown pharmaceutical light-proof bottle according to claim 1, characterized in that, The materials for both the structural exterior layer (101) and the internal cleanroom layer (103) are polyolefin materials.

7. A three-layer co-extrusion blown pharmaceutical light-proof bottle according to claim 1, characterized in that, The material of the dark light-blocking layer (102) is a polyolefin material including a light-blocking agent.

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