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EP-3941841-B1 - SELF-CLOSING DISPENSING VALVE MADE OF A PLASTOMER OR A THERMOPLASTIC ELASTOMER

EP3941841B1EP 3941841 B1EP3941841 B1EP 3941841B1EP-3941841-B1

Inventors

  • PATER, MARCEL
  • MERTENS, Alwin
  • DEN BOER, SEBASTIAAN WILHELMUS JOSEPHUS
  • ELLENKAMP-VAN OLST, Lenny Marita

Dates

Publication Date
20260513
Application Date
20200317

Claims (15)

  1. Self-closing dispensing valve (1, 101) made of an elastic material, said valve comprising a valve head (2, 102) with a dispensing orifice, a circular peripheral retaining flange (4, 104) spaced apart from the valve head (2, 102) in an axial direction, and a connecting sleeve (5, 105) integrally connected with the valve head (2, 102) on one end and the retaining flange (4, 104) on another end, wherein: - the elastic material is a plastomer or a thermoplastic elastomer, - the valve head (2, 102) has a dome shape with a concave exterior (6, 106) side and a convex interior side (7, 107), - the valve head (2, 102) is connected to said end of the connector sleeve (5, 105) by a hinge portion (8, 108) , characterized in that the hinge portion (8, 108) is U-shaped in cross section, the connecting sleeve (5, 105) is substantially form stable, and wherein the wall thickness of the hinge portion (8, 108) is smaller than the wall thickness of the connector sleeve (5, 105) and is staggered at the transition (9, 109) between the connector sleeve (5, 105) and the hinge portion (8, 108).
  2. Self-closing valve according to claim 1, wherein the wall thickness of the hinge portion (8, 108) is smaller than the wall thickness of the valve head (2, 102).
  3. Self-closing valve according to any of the preceding claims, wherein the hinge portion (8, 108) has a uniform wall thickness.
  4. Self-closing valve according to any of the preceding claims, wherein the connector sleeve (5, 105) has a uniform wall thickness.
  5. Self-closing valve according to any of the preceding claims, wherein the wall thickness of the connector sleeve (5, 105) is at least twice the wall thickness of the hinge portion (8, 108).
  6. Self-closing valve according to any of the preceding claims, wherein the valve head (2) is made of a plastomer material.
  7. Self-closing valve according to claim 6, wherein the valve head (2) has a uniform wall thickness.
  8. Self-closing valve according to any of the claims 6 - 7, wherein the valve head (2) has a diameter D vh , and wherein the concave exterior side (6) of the valve head (2) has a radius of curvature R1, wherein 0,90 ≤ D vh /R1 ≤ 1,15, preferably about 1,00.
  9. Self-closing valve according to any of the claims 1 - 7, wherein the valve head (102) is made of a thermoplastic elastomer material.
  10. Self-closing valve according to claim 9, wherein the valve head (102) has a wall thickness that tapers towards the centre of the valve head.
  11. Self-closing valve according to claim 10, wherein the wall thickness of the valve head (102) at the centre is 2/3 of the wall thickness at the circumference of the valve head (102).
  12. Self-closing valve according to any of the claims 9 -11, wherein the valve head (102) has a diameter D vh , and wherein the concave exterior side (106) of the valve head (102) has a radius of curvature R1, wherein 1,2 ≤ D vh /R1 ≤ 1,6, preferably about 1,5.
  13. Self-closing valve according to any of the preceding claims, wherein the connector sleeve (5, 105) is substantially cylindrical, preferably slightly tapering.
  14. Self-closing valve according to any of the claims 1 - 12, wherein the connector sleeve (5, 105) is at least partly tapering from the retaining flange (4, 104) towards the valve head (2, 102).
  15. Self-closing valve according to any of the preceding claims, wherein the dispensing orifice is defined by at least one through slit (3, 103) in the valve head (2, 102), preferably multiple through slits (3, 103) intersecting at the centre of the valve head (2, 102), more preferably two through slits (3, 103) intersecting at the centre of the valve head (2, 102).

Description

The invention relates to a self-closing dispensing valve made of an elastic material, said valve comprising a valve head with a dispensing orifice, a circular peripheral retaining flange spaced apart from the valve head in an axial direction, and a connecting sleeve integrally connected with the valve head on one end and the retaining flange on another end. This type of self-closing valves is well known and is mounted commonly in dispensing closures to be arranged on a container containing a substance to be dispensed. Well known applications are for example dispensing closures for squeeze bottles such as ketchup, mayonnaise, honey bottles and container for other edible substances. Another example is dispensing closures for squeezable bottles for haircare, bodycare or cleaning products. When the container is squeezed and thus the interior is pressurized, the valve orifice opens and the substance can be dispensed through the valve. After the pressure on the container is relieved, the valve closes automatically due to the elasticity of the valve material. An example of such a valve is shown in WO 2008/074517. Figs. 3 to 5 of WO 2008/074517 show a self-closing valve integrally formed of silicone rubber by injection moulding. It has a valve head with a circular outer contour, a concave outer surface and a convex inner surface. The valve furthermore has a circular retaining flange at an axial distance from the valve head, by which the valve can be fixed to a dispensing closure. The axially offset valve head and retaining flange are connected by a connector sleeve which has substantially a cylindrical or a frusto-conical shape. The valve is placed and fixed to a dispensing closure which is adapted to be coupled to a container with a dispensible content such as foodstuffs, e.g. ketchup or other sauces, or such as cosmetic or care products. The valve head is provided with slits which form a dispensing orifice which opens upon pressurization of the container. Although silicone rubber valves are very fit for their purpose they pose a problem after use, when the user throws away the container with the dispensing closure in which the valve is still fixed. The containers and the dispensing closure are usually made of a recyclable plastics material such as PET, PE or PP. However, the silicone material cannot be recycled and therefore disturbs the recycle streams of the containers and closures. One way to circumvent the recycling problem is to separate the self-closing valves from the closures during recycling. In WO 2008/097306 a method is disclosed for flotation separation of silicone and plastic. The document describes as an example plastic bottles with a valve diaphragm made of cured silicones which can be separated by using a low-gravity silicone for the valves which allows the materials to be separated and the plastic can be recycled. Another way to circumvent the recycling problem is to use another material for the self-closing valves. For example in US 6,726,063 it is proposed to make the self-closing valve from a thermoplastic elastomer (TPE), which has the advantage that it can be processed and recycled like thermoplastic materials, which makes it is easier to recycle scrap because the TPE of the valves and the thermoplastic materials of the other package items, such as closures and containers does not have to be separated but can be processed together. US 6,726,063 shows many valves with different slit shapes and positions in the valve head to enhance the control of dispensing through the valve head. WO 01/32552 discloses a self-closing valve in accordance with the preamble of appended claim 1 to be mounted in a closure body. The self-closing valve has an annular groove formed in the connecting sleeve. The groove is adapted to receive an annular mounting flange formed on an inner side of an annular wall of the closure body. This valve is preferably molded from a silicone rubber, but alternatively the valve can also be molded from thermoplastic elastomers (TPE). A disadvantage of TPE compared to silicone rubber for self-closing dispensing valves is that TPE grades having similar mechanical properties as the used silicone materials are often not suitable for use with different food products. In particular when used with fatty food products, the TPE grades which have similar mechanical properties as silicone materials show too much migration of agents into the food product. TPE grades which are suitable for use with fatty foods are typically stiff and cannot be used with known valve designs used in the food packaging industry. The present invention has for an object to provide an improved self-closing dispensing valve, which is compatible with the dispensing of foodstuffs but avoids the use of silicone materials. This object is achieved by a self-closing valve according to claim 1. The valve according to the invention can be made by injection moulding or injection compression moulding. The dispensing orifice is for