Acid-resistant metal bottle cap for food

Abstract

The utility model relates to food packaging container technical field discloses a kind of acid corrosion-resistant metal bottle caps for food, including main body and sealing mechanism fixedly connected to the sealing mechanism bottom outer wall of main body, main body includes 316 stainless steel support load layer, biological epoxy resin base material isolation adhesion layer and polytetrafluoroethylene film food contact corrosion-resistant layer in turn from inside to outside, the surface of main body middle part is provided with anti-skid lines, sealing mechanism includes anti-skid thread, sealing ring, sealing thread and limit ring, anti-skid thread is along main body bottom outer wall circumferential spiral extension, limit ring is integrally formed on main body outer wall and located above anti-skid thread, sealing ring is embeddedly fixedly connected to main body bottom outer wall and sealing ring surface has protruding sealing thread.The utility model directly resists acidic erosion and prevents metal ion precipitation by three-layer composite structure, prevent excessive screwing and liquid leakage by limit ring and multistage sealing structure, with the advantages of strong corrosion resistance and reliable sealing.

Description

Technical Field

[0001] This utility model relates to the field of food packaging container technology, and in particular to an acid-resistant metal bottle cap for food. Background Technology

[0002] In the food and beverage packaging industry, metal bottle caps are widely used for encapsulating various glass and plastic bottles due to their excellent mechanical strength, impact resistance, and good molding and processing performance. However, when acidic foods or products such as vinegar, juice, and fermented sauces are transported and stored in high-salt and high-humidity marine environments, traditional metal bottle caps face severe corrosion resistance challenges. Ordinary metal substrates are prone to electrochemical corrosion or chemical reactions after prolonged contact with acidic media or salt spray environments, resulting in rust spots or even perforations on the inner surface of the bottle cap. More seriously, the corrosion process is often accompanied by the precipitation and migration of metal ions into the food inside the bottle. This not only changes the original flavor and color of the food and accelerates its oxidation and spoilage, but also leads to excessive levels of heavy metals, posing a potential threat to consumers' food safety and health.

[0003] While existing technologies attempt to mitigate corrosion by spraying anti-corrosion coatings onto metal surfaces, traditional single-coat structures often suffer from defects such as insufficient adhesion and high brittleness. During the deformation process of opening and tightening the cap, the coating is prone to micro-cracks or peeling, which in turn allows acidic liquids to seep in and corrode the substrate. In addition, the sealing structure of existing metal bottle caps is relatively simple, usually lacking effective travel limits and multi-stage sealing mechanisms. When the user tightens the cap with excessive force, it is easy to crush the internal sealing material, leading to seal failure. Insufficient tightening force, on the other hand, will result in an incomplete seal. This unstable sealing state not only causes acidic contents to leak and contaminate the outside of the bottle, but also introduces outside air to accelerate the internal corrosion process, making it difficult to meet the stringent requirements of high safety and long-term sealing for packaging containers of highly acidic foods.

[0004] Therefore, this utility model proposes an acid-resistant metal bottle cap for food to overcome the shortcomings of the prior art. Utility Model Content

[0005] In view of the problems in the prior art, metal bottle caps are prone to corrosion when containing acidic foods or in marine transportation and storage environments with high salt and high humidity, which leads to the release of metal ions and contamination of the food. In addition, the existing bottle cap sealing structure is relatively simple and lacks effective stroke limit and multi-stage sealing mechanism, which makes it easy to damage the structure due to over-screwing and the sealing and anti-leakage effect is unstable. The present invention aims to provide an acid-corrosion resistant metal bottle cap for food with an improved structure that can effectively solve the above problems.

[0006] This utility model provides an acid-resistant metal bottle cap for food, comprising: a main body with anti-slip texture on the middle surface of the main body; and a sealing mechanism fixedly connected to the outer wall of the bottom of the main body.

[0007] The main body has a three-layer composite structure arranged sequentially from the inside to the outside. The main body includes a support and bearing layer, a substrate isolation and attachment layer adhered to the outer surface of the support and bearing layer, and a food contact corrosion-resistant layer composited to the outer surface of the substrate isolation and attachment layer. The sealing mechanism includes anti-slip threads, a sealing ring, a sealing pattern, and a limiting ring. The limiting ring has an annular boss-shaped structure and is integrally formed on the outer wall of the main body. The surface of the sealing ring has raised sealing patterns.

[0008] Furthermore, anti-slip threads are provided on the bottom outer wall of the main body, and the limiting ring is located above the anti-slip threads to limit the screwing stroke of the main body. The sealing ring is embedded and fixedly connected to the bottom outer wall of the main body and located below the anti-slip threads. The sealing ring fills the gap between the main body and the bottle mouth by deforming under pressure and cooperating with the sealing pattern.

[0009] Preferably, the supporting layer serves as the main basic support structure, the material of the supporting layer is 316 stainless steel, the supporting layer is located inside the substrate isolation layer, and the thickness of the supporting layer is limited to between 0.2 mm and 0.3 mm.

[0010] Preferably, the substrate isolation layer is tightly attached to the surface of the support layer to isolate the substrate. The substrate isolation layer is made of bio-based epoxy resin, and the thickness of the substrate isolation layer is limited to between 15 micrometers and 25 micrometers.

[0011] Preferably, the food contact corrosion-resistant layer constitutes the outermost surface of the main body, the material of the food contact corrosion-resistant layer is polytetrafluoroethylene film, and the thickness of the food contact corrosion-resistant layer is limited to between five micrometers and twelve micrometers.

[0012] Preferably, the anti-slip thread extends circumferentially along the outer wall of the bottom of the main body, and the anti-slip thread is used to engage with the bottle neck thread, and the lower end of the anti-slip thread extends to the bottom edge of the main body.

[0013] Preferably, the outer diameter of the limiting ring is larger than the outer diameter of the anti-slip thread to form a blocking structure. The limiting ring is used to limit the maximum stroke when the main body is screwed on, preventing structural damage due to excessive force.

[0014] Preferably, the sealing ring is made of elastic rubber. When the sealing ring is compressed, it undergoes elastic deformation to fill the gap between the main body and the bottle mouth. The sealing pattern includes multiple annular ridges evenly distributed along the circumference of the sealing ring. The sealing pattern protrudes from the surface of the sealing ring to increase the contact area.

[0015] Preferably, the anti-slip texture is located above the limiting ring. The anti-slip texture consists of several vertical strip-shaped protrusions evenly arranged along the circumference of the main body. The anti-slip texture is used to increase the friction between the hand and the main body.

[0016] This utility model has the following beneficial effects: 1. This utility model solves the problem of existing metal bottle caps easily corroding and causing metal ion release to contaminate food when in contact with acidic foods or in highly corrosive environments such as seawater by adopting a three-layer composite main structure consisting of a support and bearing layer, a substrate isolation and adhesion layer, and a food contact corrosion-resistant layer. It achieves the effect of using the extremely strong chemical stability of polytetrafluoroethylene film to directly resist acid corrosion, using the substrate isolation and adhesion layer to isolate the metal substrate from external contact to prevent ion release, and using the 316 stainless steel support and bearing layer to ensure the overall structural strength and impact resistance.

[0017] 2. This utility model solves the problems of easy leakage and structural damage caused by excessive screwing in existing bottle cap sealing structures by setting a sealing mechanism including anti-slip threads, a limiting ring, and a sealing ring with sealing patterns at the bottom of the main body. It achieves the effect of limiting the maximum stroke of the main body by the limiting ring to protect the integrity of the structure, and using the pressure deformation of the sealing ring in conjunction with the sealing patterns to increase the contact area to form multiple sealing defenses, thereby effectively preventing air from entering and acidic food from leaking.

[0018] 3. This utility model solves the problems of insufficient environmental performance of existing petroleum-based materials and difficulty in opening bottle caps due to their smooth surface by using bio-based epoxy resin as the isolation and adhesion layer of the substrate and setting anti-slip texture on the surface of the main body. It achieves the effects of reducing carbon footprint by using biomass materials, ensuring the stability of the composite structure by using the excellent adhesion of bio-based epoxy resin, and increasing the friction between the hand and the main body to improve the ease of operation. Attached Figure Description

[0019] Figure 1 This is a perspective view of an acid-resistant metal bottle cap for food products proposed in this utility model. Figure 2 This is a cross-sectional view of the main body of an acid-resistant metal bottle cap for food proposed in this utility model; Figure 3 for Figure 2 Enlarged view of point A in the middle; Figure 4 This is an exploded view of an acid-resistant metal bottle cap for food products proposed in this utility model. Figure 5 A three-dimensional view of a sealing ring for an acid-corrosion-resistant metal bottle cap for food, as proposed in this utility model; Figure 6 This is a bottom view of an acid-resistant metal bottle cap for food, as proposed in this utility model.

[0020] Legend: 1. Main body; 101. Supporting and bearing layer; 102. Substrate isolation and adhesion layer; 103. Food contact corrosion resistant layer; 2. Sealing mechanism; 201. Anti-slip thread; 202. Sealing ring; 203. Sealing pattern; 204. Limiting ring; 3. Anti-slip texture. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the protection scope of this utility model.

[0022] Example: Please refer to Figures 1 to 6 This utility model provides an acid-resistant metal bottle cap for food, which aims to solve the problems in the prior art where metal bottle caps are prone to corrosion when in contact with acidic foods or in harsh seawater environments, leading to the precipitation of metal ions, and where traditional sealing structures are prone to leakage and damage due to excessive screwing.

[0023] Please refer to Figure 1 and Figure 2 The acid-resistant metal bottle cap for food includes a main body 1 and a sealing mechanism 2 fixedly connected to the bottom outer wall of the main body 1. The main body 1 serves as the basic support frame for the bottle cap and provides multi-level corrosion protection. The sealing mechanism 2 is used to realize the mechanical screw-on connection between the bottle cap and the bottle mouth, the stroke limit, and the leak-proof sealing function.

[0024] Please refer to Figure 2 , Figure 3 and Figure 4The main body 1 comprises, from the inside out, a supporting layer 101, a substrate isolation layer 102, and a food contact corrosion-resistant layer 103. The supporting layer 101 serves as the inner core of the main body 1, with the substrate isolation layer 102 adhered to its outer surface. The food contact corrosion-resistant layer 103 is then laminated to the outer surface of the substrate isolation layer 102. This hierarchical structure isolates the supporting layer 101 from the external environment through the substrate isolation layer 102 and provides the outermost chemical protection through the food contact corrosion-resistant layer 103. Simultaneously, a sealing mechanism 2 is fixedly connected to the bottom outer wall of the main body 1. The sealing mechanism 2 specifically includes an anti-slip thread 201, a sealing ring 202, a sealing groove 203, and a limiting ring 204. The anti-slip thread 201 extends circumferentially along the bottom outer wall of the main body 1 and is used to engage with the bottle neck thread for tightening and fixing. The limiting ring 204 is integrally formed on the outer wall of the main body 1 and is located at... Above the anti-slip thread 201, the limiting ring 204 has an annular boss-shaped structure with an outer diameter larger than that of the anti-slip thread 201. This serves to block and limit the movement of the main body 1 during the screwing process, preventing damage to the structure of the main body 1 due to excessive screwing. The sealing ring 202 is embedded and fixedly connected to the bottom outer wall of the main body 1, and is positioned below the anti-slip thread 201. The surface of the sealing ring 202 has multiple circumferentially evenly distributed sealing patterns 203. In the assembled state, the sealing ring 202 undergoes elastic deformation under pressure to fill the gap between the main body 1 and the bottle mouth. The sealing patterns 203 further increase the contact area to improve airtightness. In addition, the middle surface of the main body 1, above the limiting ring 204, is also provided with anti-slip texture 3. The anti-slip texture 3 consists of several vertical strip-shaped protrusions evenly arranged along the circumference of the main body 1, which are used to increase the friction between the hand and the bottle cap when screwing the main body 1.

[0025] As a preferred embodiment, in order to ensure that the bottle cap has high strength and excellent seawater corrosion resistance, the support layer 101 is made of 316 stainless steel, and the thickness of the support layer 101 is strictly limited to between 0.2 mm and 0.3 mm. The thickness range ensures the impact resistance of the main body 1 and avoids the bottle cap from being too thick and heavy.

[0026] As another preferred embodiment, in order to reduce the carbon footprint and enhance the adhesion between the coating and the metal substrate and the outer film, the substrate isolation layer 102 is made of bio-based epoxy resin. The thickness of the substrate isolation layer 102 is limited to between 15 micrometers and 25 micrometers. The thickness can effectively fill the fine unevenness of the 316 stainless steel surface and form a smooth transition layer.

[0027] As another preferred embodiment, in order to ensure that the surface of the main body 1 has extremely strong chemical stability and high and low temperature resistance, the food contact corrosion resistant layer 103 is made of polytetrafluoroethylene film. The thickness of the food contact corrosion resistant layer 103 is limited to between five micrometers and twelve micrometers. The thickness allows the polytetrafluoroethylene film to provide an acid corrosion barrier while maintaining good flexibility and preventing cracking due to excessive thickness.

[0028] As another preferred embodiment, in order to improve the long-term reliability of the sealing structure, the sealing ring 202 is preferably made of acid and alkali resistant elastic rubber material, and the sealing pattern 203 is annularly raised on the surface of the sealing ring 202 so as to form multiple independent sealing lines when in contact with the bottle mouth.

[0029] Working principle: Under normal use and storage conditions, the support and bearing layer 101 serves as the basic skeleton of the main body 1, bearing the main structural strength requirements. The support and bearing layer 101 utilizes the characteristics of 316 stainless steel to provide basic corrosion resistance and impact resistance. The substrate isolation and adhesion layer 102 located in the middle is tightly attached to the surface of the support and bearing layer 101. The substrate isolation and adhesion layer 102 fills the minor unevenness on the surface of the support and bearing layer 101 and isolates the substrate from direct contact with the external environment, thereby preventing the precipitation of metal ions. The outermost food contact corrosion-resistant layer 103 is in direct contact with food. The food contact corrosion-resistant layer 103 utilizes the extremely strong chemical stability of polytetrafluoroethylene film to directly resist the long-term corrosion of acidic foods, while using non-stick properties to prevent food residue from adhering to the inside of the main body 1.

[0030] When sealing the bottle opening is required, the hand holds the anti-slip texture 3 in the middle of the main body 1. The anti-slip texture 3 increases friction to facilitate the rotation of the main body 1. During rotation, the anti-slip thread 201 at the bottom of the main body 1 engages with the thread of the bottle opening. As the main body 1 continues to rotate, the limiting ring 204 fixed on the outer wall of the main body 1 gradually approaches the bottle opening structure. When the limiting ring 204 contacts the designated position of the bottle opening, the limiting ring 204 restricts the continued rotation of the main body 1, thereby avoiding over-rotation that could damage the structure. At the same time, the sealing ring 202 located at the bottom of the main body 1 is squeezed between the main body 1 and the bottle opening. The sealing ring 202 undergoes elastic deformation to fill the gap. The sealing texture 203 on the surface of the sealing ring 202 further increases the contact area and forms multiple sealing lines, thereby achieving a stable and reliable seal on the bottle opening and effectively preventing air from entering and acidic food from leaking.

Claims

1. An acid-resistant metal bottle cap for food, comprising: The main body (1) includes a support bearing layer (101), a substrate isolation layer (102) is adhered to the outer surface of the support bearing layer (101), a food contact corrosion resistant layer (103) is laminated to the outer surface of the substrate isolation layer (102), and anti-slip texture (3) is provided on the middle surface of the main body (1). Its features are, A sealing mechanism (2) is fixedly connected to the bottom outer wall of the main body (1). The sealing mechanism (2) includes an anti-slip thread (201), a sealing ring (202), a sealing pattern (203), and a limiting ring (204). The anti-slip thread (201) is disposed on the bottom outer wall of the main body (1). The limiting ring (204) is integrally formed on the outer wall of the main body (1) and located above the anti-slip thread (201). The sealing ring (202) is embedded and fixedly connected to the bottom outer wall of the main body (1). The sealing pattern (203) is disposed on the surface of the sealing ring (202).

2. The acid-resistant metal bottle cap for food as described in claim 1, characterized in that, The support bearing layer (101) serves as the basic support structure of the main body (1). The material of the support bearing layer (101) is 316 stainless steel. The thickness of the support bearing layer (101) is limited to between 0.2 mm and 0.3 mm. The support bearing layer (101) is located inside the substrate isolation attachment layer (102).

3. The acid-resistant metal bottle cap for food as described in claim 1, characterized in that, The substrate isolation layer (102) is tightly attached to the surface of the support layer (101) to isolate the substrate. The substrate isolation layer (102) is made of bio-based epoxy resin, and the thickness of the substrate isolation layer (102) is limited to between 15 micrometers and 25 micrometers.

4. The acid-resistant metal bottle cap for food as described in claim 1, characterized in that, The food contact corrosion resistant layer (103) constitutes the outermost surface of the main body (1). The food contact corrosion resistant layer (103) is made of polytetrafluoroethylene film, and the thickness of the food contact corrosion resistant layer (103) is limited to between five micrometers and twelve micrometers.

5. The acid-resistant metal bottle cap for food as described in claim 1, characterized in that, The anti-slip thread (201) extends circumferentially along the bottom outer wall of the body (1), the anti-slip thread (201) is used to engage with the bottle neck thread, and the lower end of the anti-slip thread (201) extends to the bottom edge of the body (1).

6. The acid-resistant metal bottle cap for food as described in claim 1, characterized in that, The limiting ring (204) has an annular boss-shaped structure. The outer diameter of the limiting ring (204) is larger than the outer diameter of the anti-slip thread (201) to form a blocking structure. The limiting ring (204) is used to limit the maximum stroke of the main body (1) when it is screwed in.

7. The acid-resistant metal bottle cap for food as described in claim 1, characterized in that, The sealing ring (202) is made of elastic rubber. The sealing ring (202) is located below the anti-slip thread (201). The sealing ring (202) undergoes elastic deformation after being compressed to fill the gap between the main body (1) and the bottle mouth.

8. The acid-resistant metal bottle cap for food as described in claim 1, characterized in that, The sealing pattern (203) includes multiple annular raised ridges evenly distributed along the circumference of the sealing ring (202), and the sealing pattern (203) protrudes from the surface of the sealing ring (202) to increase the contact area.

9. The acid-resistant metal bottle cap for food as described in claim 1, characterized in that, The anti-slip texture (3) is located above the limiting ring (204), and the anti-slip texture (3) is composed of several vertical strip protrusions evenly arranged along the circumference of the main body (1).

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