A teat

FIELD OF THE INVENTION

The present invention relates to a teat primarily for a baby feeding bottle and to a device and methods of manufacturing a teat for a baby feeding bottle.

BACKGROUND OF THE INVENTION

The chief aim of a teat is to provide liquid feed from a bottle to infants. The teat is formed from a thin- walled flexible rubber material that resembles the shape and flexibility of a natural breast with the aim of replicating a natural breast feeding action. This involves the infant creating a negative pressure by sucking its mother's breast in order to form a teat from the nipple, areola and the underlying tissue. When the teat is created the infant performs a peristaltic stripping movement with its tongue and consequently the infant receives milk. Newborn babies have only little strength and the flexible structure of mothers' breasts enables infants to latch on to the breast with minimum effort creating an airtight seal with their mouth. The seal is an important factor in the natural breast feeding action as it minimises the ingestion of air which can cause digestion problems and/or colic. Generally, the problem of ingesting air is not known regarding infants who are breast fed, however it is an established problem concerning bottle fed infants. By implication, it is generally apparent that infants have more difficulties in creating an airtight seal with their mouths to a teat than to a breast. A further recognised problem with teats and bottle feeding is nipple confusion.

Infants may experience confusion when switching between breast and bottle as teats are inherently different in texture and structure to the natural breast. Furthermore, teats generally tend to promote a different kind of feeding action than natural breast feeding. As a result of nipple confusion, the infant may experience difficulty adjusting to bottle feeding. Current teats are designed to imitate a natural breast in terms of texture and structure. Known teats disclosed in US20040220618 and US20030039121 have regions that are textured to imitate the skin of the nipple and configured to crudely replicate the geometry of a universal/general breast. However, these devices suffer from poor deformability making it harder for an infant to establish an airtight seal.

It is also known from DE 202004014860 and US20040245203 to provide teats having separate inner and outer walls. The outer wall is highly flexible so that it readily deforms around the infant's lips to promote sealing whereas the inner wall is formed from a less flexible material so as to prevent the teat from collapsing. A disadvantage is that the success of these double-walled teats, in terms of good fit to the infant's mouth, is limited to the elastic properties of the material of the outer wall.

As the aforementioned teats are of a double walled construction comprising separate inner and outer parts, they are more complex to manufacture than single walled teats formed from a single component. They are also more difficult to clean and sterilise. It is desirable to provide a teat that adapts more closely to the mouth of an infant so as to improve the sealing effect, thereby mimicking the sealing effect obtained during natural breast feeding, without unduly increasing the complexity of a conventional teat.

SUMMARY OF THE INVENTION

The present invention seeks to provide a teat for a baby feeding bottle that overcomes or substantially alleviates the problems mentioned above.

According to the present invention, there is provided a teat comprising a body having at least a flexible wall portion with a pocket to receive a substance so as to alter the flexibility of the wall in a region of the pocket.

Preferably, the body has a nipple region for insertion into the mouth of an infant and the pocket surrounds the nipple region.

The pocket may at least partially extend into the nipple region. In one embodiment, the teat has a single pocket that extends circumferentially around the nipple region.

In an alternative embodiment, the teat has multiple pockets spaced from each other circumferentially around the nipple region.

In another embodiment the pockets are interconnected. Preferably, the or each pocket is integrally formed within the flexible wall of the body of the teat.

Conveniently, the or each pocket defines a sealed cavity within the wall of the body of the teat.

In one embodiment, the teat has pores configured to allow egress of fluid out of the pocket through said wall.

Preferably, the wall forms two layers in the region of the or each pocket, the thickness of each layer being less than the thickness of the wall away from the pocket. In one embodiment, the layers comprise an innermost layer and an outermost layer and wherein the thickness of the innermost layer is the same or greater than the thickness of the wall away from the pocket.

Preferably, the combined thickness of the two layers in the region of the or each pocket is less than or equal to the thickness of the wall away from the pocket. Conveniently, a substance such as gas, liquid, oil, powder or a solid may be disposed in the at least one pocket.

In one embodiment, the inner surface of the pocket is coated to prevent leakage or diffusion of the substance through the wall.

In an alternative embodiment, the substance is contained within a sealed bag within the at least one pocket to prevent leakage or diffusion of the substance through the wall.

Preferably, the nipple region has an aperture for the passage of feed through the teat.

Conveniently, the teat is for use with a feeding bottle. In accordance with the invention, there is also provided a pacifier incorporating the teat.

According to the present invention, there is a method of manufacturing a teat comprising moulding the body with a wall portion extending from an inner or outer surface of the wall of the teat and subsequently attaching a free end of said wall portion to said inner or outer surface to form a pocket between said wall portion and the inner or outer surface of the wall of the teat.

In one embodiment, the step of attaching the wall portion to said inner or outer surface includes welding or bonding the wall portion to said inner or outer surface.

In an alternative embodiment, the step of decreasing the size of the pocket by sealing more of the wall portion to the inner or outer surface of the body.

Preferably, the step of attaching the wall portion to the inner or outer surface of the wall of the teat includes bringing the free end of the wall portion into contact with the inner or outer surface of the body at one edge of the body and inserting said end of the wall

portion and edge of the body into a mould that holds the free end and edge together, and moulding a clamping component around them.

In a preferred embodiment, the clamping component is shaped into a screw ring for attaching the body to a baby feeding bottle. The method of manufacturing the teat may further include the step of filling the pocket with a substance prior to, or after, attaching the wall portion to the inner or outer surface of the body of the teat.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention and methods of manufacturing will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows a cross-sectional view of a teat according to the present invention; Figure 2 shows a cross-sectional view of the teat of figure 1 with applied pressure;

Figure 3 a shows a cross-sectional view of a teat prior to the formation of a circumferential pocket;

Figure 3b shows a cross-sectional view of the teat in figure 3 a with the circumferential pocket welded to the inner wall of the teat;

Figure 3c shows a cross-sectional view of the teat in figure 3b injected with a substance;

Figure 4a shows a cross-sectional view of a teat prior to the formation of a circumferential pocket according to another embodiment; Figure 4b shows a cross-sectional view of the teat in figure 4a filled with substance;

Figure 4c shows a cross-sectional view of the teat in figure 4b with the circumferential pocket closed;

Figure 4d shows a cross-sectional view of the teat in figure 4c with the circumferential pocket sealed;

Figure 5 a shows a cross-sectional view of a teat prior to the formation of a gas filled circumferential pocket;

Figure 5b shows a cross-sectional view of the teat in figure 5b with the circumferential pocket filled with gas closed;

Figure 5 c shows a cross-sectional view of the teat in figure 5 c with the circumferential pocket with gas sealed;

Figure 6a shows a cross-sectional view of a device for moulding a teat; Figure 6b shows a cross-sectional view of the device in figure 6a with an unfinished moulded teat;

Figure 6c shows a cross-sectional view of a device for sealing the teat in figure 6c;

Figure 6d shows a cross-sectional view of the device and the teat in figure 6c, however the teat is sealed and an integral mould is provided for manufacturing a screw ring; Figure 7a shows a cross-sectional view of a device for filling the pockets and sealing the teat in figure 6b;

Figure 7b shows a cross-sectional view of the device and the teat in figure 7a, however the teat is sealed and an integral mould is provided for manufacturing a screw ring.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring now to the drawings, there is shown in Figure 1 and 2 a teat 10 comprising a body 11 having a mouthpiece or nipple region 12 according to an embodiment of the present invention. The body 11 comprises a wall 13 with an inner surface 14 and an outer surface 15. The inner surface of the wall 13 defines a cavity 16 that narrows into a duct 17 within the nipple region 12. At least one aperture 18 is formed in the tip of the nipple region 12 so that milk flows from the cavity 16 into the duct 17 and through the aperture 18 into the infant's mouth during feeding. The lower end of the cavity 16 remote from the nipple region 12 is open and the wall is provided with means to enable the teat to be attached to a feeding bottle (not shown) as is conventional. The wall 13 is provided with an integral pocket 19 that may at least partially extend into the nipple region 12. The teat 10 may have a single pocket 19 that extends circumferentially all the way around the body 11 , although it is envisaged that it may extend only partially around the body 14 or that there may be separate individually spaced pockets 19 positioned circumferentially around the body 11. Where there are multiple pockets 19, each pocket 19 may be discrete or independent from its adjacent pocket 19 although they may also be interconnected by an integrally formed duct or passageway (not shown) between them. The or each pocket 19 defines a void or cavity within the wall 13 of the body 11 which may be filled with any kind of substance such as gas, air, liquid, solid, oil or powder, thereby altering the flexibility of the body 11 of the teat 10 in the area of the pocket(s) 19 so that the

wall 13 adapts more closely to the mouth of an infant whilst maintaining a sufficiently high degree of rigidity to prevent the teat from collapsing in the infant's mouth.

It will be appreciated that the pockets may assume a wide variety of different shapes and locations within the wall 16 of the teat. Although the or each pocket 19 is integral with the wall 13, the wall effectively has two layers 13a, 13b in the region of the pocket 19. These layers 13a, 13b may each be of the same thickness as the remainder of the wall 13, although it is envisaged that they will each be of reduced thickness so that their combined thickness is less than or equal to the thickness of the remaining part of the wall 13 away from the pockets 19. It will also be appreciated that the thickness of each layer 13 a, 13b may be different. For example, the thickness of the outer layer 13a may be thinner and more flexible than the inner layer 13b. In particular, collapse of the nipple region 12 may be prevented by increasing the strength of the inner layer 13b. When an infant sucks on the nipple region 12, its lips exert compressive forces on the main body 11, particularly in the area of the pocket(s) 19. Due to the enhanced flexibility of the wall 13 in the area of the pocket(s) 19, the wall deforms so as to adapt to the shape of the infant's lips, thereby creating an airtight seal between the infant's lips and the teat 10 so as to minimise the volume of air consumed by the infant. The improved flexibility and touch of the teat also imitates the natural breast tissue, thereby minimising nipple confusion. In embodiments in which there are a plurality of interconnected pockets, the substance contained within them may be free to move form one pocket to another.

It will be appreciated that the volume and type of substance contained in the cavities formed by the pockets 19 can be selected so as to control the flexibility or deformability of the teat 10 to suit individual infants. There may also be a mix of substances in one pocket or a plurality of pockets may have different substances. It is envisaged that teats will be sold pre-filled and that the pockets 19 will be sealed during manufacture. However, it is also envisaged that the pockets 19 could be filled by the purchaser prior to use with a chosen substance depending on the degree of flexibility or deformability required.

The teat may be made out of materials which change colour due to change in pressure or heat. Materials which change their appearance due to tear and wear or phase change material that gives a warm feeling to the teat are advantageous as they may enhance the performance of the teat. For teats made out of translucent material, floating particles, air bubbles in oil based substances or images can also be provided in the pockets. Other features

of the teat may include balls in air filled pockets that rattle when shaken so as to provide amusement to the infant or attract them to the teat so as to promote feeding.

Tools for, and methods of, manufacturing the teat 10 shown in Figure 1 and 2 will now be described with reference to Figures 3 to 7. Figures 3 a to 3 c show the steps of manufacturing a teat 10 having a pocket 19 according to an embodiment of the invention, such as that shown and described with reference to Figure 1. The teat 10 is initially formed in a moulding process so as to include a generally annular integrally formed flap 20 extending from the wall 13 on the inside of the teat 10. The pocket 19 is formed by welding the free outer edge of the flap 20 to the wall 13, as shown in Figure 3b. At the welding region 21, the material melts locally resulting in a chemical bond between the wall 13 and the edge of the flap 20 so as to form a sealed pocket 19 with the two wall layer construct 13a and 13 b. The pocket 19 can then be filled with a substance by injecting it into the pocket using a syringe 22, as shown in Figure 3c. Suitable materials for these sealing methods include thermoplastics such as Styrene-Ethylene- Butylene-Styrene (SEBS).

An alternative method of manufacturing a teat 10 will now be described with reference to Figures 4a to 4d. A teat 10 is moulded with an integral flap 32 extending circumferentially on the inside of the teat 10 as seen in Figure 4a. A substance 23 is provided in the recess created between the flap 32 and the wall 13 (Figure 4b). Once filled, the pocket 19 is formed by closing the wall 13 and the flap 32 together thereby expelling overflowing substance to ensure no unwanted air is trapped in the pocket (Figure 4c). The pocket 19 is then sealed and integrated in the two layer wall construct 13a and 13b by preheating the wall 13 and the flap 32 and exposing them to compressive forces to form a chemical bond extending in the direction away from the pocket(s) 19 (Figure 4d). Another method for manufacturing a teat of the present invention will now be described in reference to Figures 5a to 5c. The overall method of manufacturing the teat is largely the same as that of the method of the previous embodiment described above, except that, in this embodiment, the substance is a gas and the direction of sealing differs, as described below. The flap 32 is closed against the wall 13 so as to trap ambient gas upon formation of the pocket 19 (Figure 5b). The pocket 19 is sealed by exerting compressive forces 24 onto the preheated wall 13 and flap 32 which subsequently form the two layer construct 13a and 13b. The pocket 19 may be reduced in size by extending the seal towards the centre of the teat 10 and thereby compressing the ambient gas in a smaller pocket 19 (Figure 5 c).

In another embodiment the pocket is sealed by mechanically pressing the flap against the wall for example by moulding a clamping part around the teat. This clamping part may also have additional functions such as a screw ring for attachment of the teat to a baby feeding bottle. Both thermoplastics and non thermoplastic materials like Liquid Silicone Rubber (LSR) are suitable for this sealing technique. The material of the clamping part should preferably have good chemical bonding properties to the teat material, or there should be a good mechanical bond.

The tool for moulding a pocket teat 10 with an integral screw ring for attachment to a feeding bottle is now described with reference to Figure 6a to 6d. The tool comprises an upper half component 30, side components 31 and a lower half component 32. The components form an integral space in the shape of a teat comprising a wall 33 split into two wall portions 34a and 34b, as shown in Figure 6a. The moulded teat 10 is separated from the upper half component 30 by moving the lower half component 32 vertically. The side component 31 may be split into more than one part to facilitate its removal. In Figure 6b the side component 31 is split into two parts for the ease of illustration. The moulded teat 10 remains on the lower half component 32 upon the removal of the other mould components (Figure 6b). Referring now to Figure 6c, a half insert 35 is positioned on top of the nipple region 12 thereby retaining the teat 10 on the lower half component 32 as a sealing component 36 is inserted. As the sealing component 36 is compressed against the lower half component 32 the two ends of the wall portions 34a and 34b are clamped and a cavity 37 is formed in the shape of a screw ring that fits onto a feeding bottle (Figure 6d). The cavity 37 is filled with a material such as plastic, and after setting the moulds are removed and the screw ring clamps the ends of the wall portions 34a and 34b which thereby constitute a pocket. In an alternative embodiment of the tool for manufacturing a teat 10 with an integral screw ring, the pocket is provided with a substance 23 prior to the sealing component clamping the wall portions. The teat 10 is moulded according to the description in the previous embodiment illustrated in Figure 6a and 6b. Referring now to Figures 7a and 7b, a half insert 40 is positioned on top of the teat 10 retaining the nipple region 12 and the body 11 on the lower half component 32 and by doing so the two wall portions 34a and 34b are very nearly closed forming a pocket 19. The small opening/partition of the wall portions 34a and 34b receives a substance injector 41 which fills the pocket 19 with a substance 23 prior to sealing. As the sealing component 42 is compressed towards the lower half component 32 the substance injector 41 is removed and a cavity 37 is formed in the shape of a screw ring

that fits onto a feeding bottle. The cavity 37 is filled with a material such as plastic, and upon setting the moulds are removed and the screw ring clamps the ends of the wall portions 34a and 34b which thereby constitute a pocket holding a substance.

Manufacture of the teat can also be achieved by moulding the teat inside out according to the previous methods.

The advantages of the methods of manufacture described herein is that the pockets can either be pre-filled at the time of manufacture or, using the method described with reference to Figures 3 a to 3 c, the pockets could be filled prior to use by a parent so as to adjust the deformability to the need of the infant. By altering the amount of substance in the pockets 19, the softness and the size of the teat may be controlled so as to satisfy both newborn babies, who generally prefer soft and smaller teats, as well as older babies and small infants who generally prefer bigger and less flexible teats to train their facial muscles.

Leakage or diffusion out of the pocket(s) may be minimised by ensuring that the particle size of the substance is larger than the pores forming the wall 13 of the teat. Furthermore, the internal surface 14 of the pocket may have a coating or the substance 23 could be enclosed in a sealed bag or pouch within the pocket.

In an alternative embodiment of the present invention the wall of the pocket(s) may have larger pores than the substance allowing for the substance to gradually leak into the teat or onto the outer surface 15 of the teat. For example, the substance may lubricate the surface of the teat, have medicinal properties or have a taste which is attractive to the infant.

Although reference is made to a teat for a baby feeding bottle, it will be appreciated that the invention is equally applicable to a pacifier. Pacifiers help infants develop muscles in their face and jaws and produce saliva. By adapting the contents of the pockets and wall thickness of the teat in the region of the pockets 28, the resistance against deformation can be varied and pacifiers with different grades of stiffness can be made.