Screw cap for liquid containers with pouring insert with integrated pressure relief valve and its use

Abstract

Screw cap for liquid containers, featuring a pouring insert with an integrated pressure relief valve that opens automatically at a preset pressure, allowing gas present in the container's headspace to escape, and closes automatically again when ambient pressure (normal pressure) is reached, thus resealing the container and preventing or minimizing the entry of air into the container.

Description

[0001] The invention relates to a screw cap for liquid containers with a pouring insert with an integrated pressure relief valve and its use for storing oxygen-sensitive liquids, which are used, for example, for nutritional, cosmetic or pharmaceutical purposes.

[0002] Vitamins and trace elements are micronutrients involved in numerous metabolic processes in the body and must be ingested regularly and in sufficient quantities through food, as the body cannot produce them itself and can only store them to a limited extent. Liquid micronutrient concentrates (hereinafter referred to as "juices") are used, for example, to supply the necessary micronutrients. These are gently produced from natural foods such as colorful vegetables, ripe fruits, berries, etc.

[0003] After the juices are filled into containers, an air-filled headspace remains above the liquid level. The oxygen contained within this headspace can degrade oxygen-sensitive juice components such as vitamins, especially vitamin C (ascorbic acid), flavonoids, and carotenoids through oxidation, causing them to lose their potency. This also leads to sensory problems such as changes in color, taste, and odor, as well as physical issues like cloudiness and precipitation caused by insoluble oxidized components or reaction products that form sediment layers at the bottom of the container. Each time the container is opened, fresh oxygen comes into contact with the juice, further accelerating the oxidative degradation of sensitive components. Dispensing juice also increases the headspace, exacerbating the situation.

[0004] Based on this, the object of the invention is to solve or at least partially alleviate the problems described above.

[0005] This problem is solved by a screw cap for liquid containers having the features of claim 1. Advantageous and / or preferred embodiments of the screw cap according to the invention are the subject of the dependent claims. The description may serve to further specify the features of the claims.

[0006] The screw cap with pouring insert and integrated pressure relief valve according to the invention has a simple design and can be manufactured cost-effectively. It minimizes oxygen ingress during storage, initial opening of a container, and repeated partial removal of the container contents, automatically releases excess pressure to the outside, and enables convenient pouring.

[0007] The invention is described in detail below, whereby the disclosed specific embodiments of the invention are intended only for illustration and are in no way to be interpreted as a limitation of the scope of protection of the invention as defined in the attached claims.

[0008] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by a person skilled in the technical field of the invention. The person skilled in the art may also refer in full to the introductory explanations.

[0009] The use of definite or indefinite articles (“der”, “die”, “das”, “ein”, “eine”) is to be understood (especially in connection with the claims) as including at least one element or component, unless otherwise stated here or the context clearly indicates otherwise.

[0010] The conjunction “or” is to be understood as an inclusive and not an exclusive “or”, i.e. as “and / or”, unless otherwise stated here or the context clearly indicates otherwise.

[0011] The use of terms such as “e.g.” (for example), “like”, or variations thereof is intended solely to better illustrate the invention and must in no way be interpreted as a limitation of the scope of protection of the invention as defined in the attached claims. Glossary

[0012] Pour spout: A pour spout is a design or additional device on a container (e.g. a bottle) or container closure that ensures that a liquid contained in the container can be poured in a controlled and drip-free manner, that the flow rate can be metered, and that backflow or spillage is prevented or reduced.

[0013] Seals: Seals for closures of liquid containers such as bottles are available in many variations – depending on the closure type, the contents, the sealing principle, the material, and the requirements for tightness, hygiene, and durability. Flat gaskets, as well as O-ring or round gaskets, are frequently used in conjunction with screw caps. Flat gaskets are simple rings made of, for example, plastic (e.g., PE, PP, TPE, PTFE, silicone), rubber (e.g., NR, NBR, EPDM), or composite material (e.g., metal-plastic composite), which seal through contact pressure between the closure and the container opening (e.g., bottle neck). O-ring or round gaskets are ring-shaped elastomers (e.g., made of silicone, EPDM) that seal through elastic deformation within the screw cap.

[0014] Throttle: A throttle is a technical device that selectively reduces or regulates the flow of fluids (gas or liquid) in a pipeline or system. Function: By narrowing the flow cross-section, flow resistance increases, resulting in a pressure drop (pressure loss) and a reduction in flow rate. Typical designs include: fixed throttle orifice (hole or narrow cross-section), throttle valve (adjustable cross-sectional opening), capillaries, or slots.

[0015] Normal pressure: In physics and engineering, normal pressure refers to the pressure that prevails under normal or standardized conditions. It is defined as the mean atmospheric pressure at sea level at 0 °C and is: p N = 101.325 kPa = 1.01325 bar (= 1 standard atmosphere, 1 atm).

[0016] Pressure relief valve: A pressure relief valve (also called a safety or one-way valve) is a self-acting device designed to prevent an impermissible or unwanted pressure increase in a closed system. How it works: Under normal operating conditions, the system pressure is below the set opening pressure (response pressure). The valve is closed, for example by a pre-tensioned spring or weight, and seals the system. If the pressure in the system rises, the force of the fluid (gas or liquid) acts on a valve disc or piston. As long as the spring force is greater than the fluid force, the valve remains closed. If the fluid force exceeds the set spring resistance, the valve opens and the fluid can flow out, resulting in a pressure reduction in the system.If the pressure drops below the set opening pressure, the spring pushes the valve disc or piston back onto the seat, the valve closes again and the system is sealed once more. Designs

[0017] The screw cap according to the invention for liquid containers has a pouring insert with an integrated pressure relief valve which opens automatically at a preset pressure (opening or response pressure) so that excess gas present or formed in the headspace of the container is released from the container, and which closes automatically again when the ambient pressure (normal pressure) is reached (or when the set opening / response pressure is undershot), thereby resealing the container and preventing or minimizing the entry of new air into the container.

[0018] The liquid container is not subject to any particular restrictions regarding shape, material, or capacity. For example, it can be a bottle (e.g., made of PET or glass) or a cuboid container made of cardboard or composite cardboard, such as those widely used for storing juices. Advantageously, the liquid containers or bottles are sufficiently mechanically stable and, in the case of sensitive ingredients, light- and oxygen-proof. Suitable containers or bottles according to the invention are commercially available in many embodiments.

[0019] The spout insert is not subject to any particular restrictions with regard to design and material. Advantageously, the spout insert can have a cutting edge or lug that enables drip-free pouring, as well as a reduced opening for metered pouring. The spout can also be extendable or hinged. Suitable spouts or spout inserts for screw caps according to the invention are commercially available in many embodiments.

[0020] Suitable pressure relief valves, which can be integrated into pouring inserts according to the invention, are commercially available in many embodiments. For example, a pressure relief valve used according to the invention can have a pre-tensioned spring that causes it to open automatically when the set opening pressure is reached and to close automatically when the opening pressure falls below the set pressure. For example, the opening pressure can be set so that an overpressure occurring in the container due to temperature or altitude changes (e.g., due to CO) is relieved. 2- (Development in carbonated beverages) is automatically reduced by opening the valve and the resulting outflow of the formed gas.

[0021] In a further embodiment of the invention, the pressure relief valve used is combined with a throttling device, wherein the throttling device is designed and arranged such that when the pressure relief valve opens, the pressure drop does not occur abruptly but gradually, thereby limiting the gas flow. For example, this can be gas guide channels provided in the valve, which narrow the flow cross-section.

[0022] The screw cap according to the invention can also have a seal for sealing against the edge of the container opening. For example, this can be a sealing ring or a circumferential sealing lip which is pressed onto the edge of the container opening or the bottle mouth when the screw cap is tightened.

[0023] In a further embodiment of the invention, the screw cap can also have a cover cap or a liner (e.g. a foil liner).

[0024] Furthermore, the invention specifies the use of the screw cap according to the invention for storing oxygen-sensitive liquids, e.g. liquids used for nutritional purposes (such as micronutrient concentrates, juices) or cosmetic or pharmaceutical purposes.

[0025] It is clear to those skilled in the technical field of the invention that the representative embodiments and details of the invention described above are intended only to illustrate the present invention, and that various changes and modifications can be made without thereby departing from the scope of protection of the invention as defined in the attached claims.

Claims

[1] Screw cap for liquid containers, which has a pouring insert with an integrated pressure relief valve that opens automatically at a preset pressure, allowing gas present in the headspace of the container to be released from the container, and closes automatically when ambient pressure (normal pressure) is reached, thereby resealing the container so that the ingress of air into the container is prevented or minimized. [2] Screw closure according to claim 1, wherein the pressure relief valve is combined with a throttling device which is designed and arranged such that when the pressure relief valve is opened the pressure drop does not occur abruptly but gradually and thereby limits the gas flow. [3] Screw cap according to claim 1 or 2, which further comprises a sealing means for sealing against the edge of the container opening. [4] Screw closure according to one of claims 1 to 3, which also has a cover cap. [5] Use of a screw cap according to any one of claims 1 to 4 for storing oxygen-sensitive liquids.