HK1059721B - Device for treating a surface, in particular a leather surface, such as that of leather shoes - Google Patents

Description

Device for treating surfaces, in particular leather surfaces, for example leather shoes

Technical Field

The invention relates to a device for treating a surface, in particular a textile surface or a leather surface, such as, for example, the upper surface of leather shoes, with a liquid substance, comprising a reservoir with a reservoir for this substance and a sponge-like body via which the substance sucked in from the reservoir can be dispersed onto the surface.

Background

Such devices are known in the form of devices suitable for polishing and lightening leather shoes. In such devices, the liquid substance is sucked through the sponge-like body and, when the sponge-like body is squeezed, the sucked substance is applied to the surface for treatment and distribution during movement thereon. The amount of liquid substance applied is determined and varied by the extent of each compression of the sponge-like body, which is undesirable.

Disclosure of Invention

The object of the present invention is to overcome this drawback at least substantially, in order to provide a device for treating surfaces, in particular textile surfaces or leather surfaces, such as, for example, the upper surface of leather shoes, which allows a more regulated outflow of liquid substances.

According to the invention, this object is achieved if the device as defined above is characterized in that between the reservoir and the sponge-like body there is at least one receiving chamber having an inflow opening communicating with the reservoir, which inflow opening is closed in the condition of non-operation of the device and can be opened upon movement of the sponge-like body relative to a plane in contact with the sponge-like body, while delaying the intake of the substance from the receiving chamber by means of the sponge-like body.

What is achieved by this measure is that at or after each operation of the device. That is, the amount of liquid substance that can be absorbed in the sponge-like body at the time of, or after, the movement of the sponge-like body relative to, in particular, the surface to be treated is completed, depending on the size of the receiving chamber. The dose of liquid substance from the receiving chamber has a value range of between 0.01 and 3ml, preferably between 0.05 and 1ml, in particular about 0.1ml, each time the chamber is filled via the inlet. In order to be able to fill the receiving chamber, there is an extended dosing element in the receiving chamber, which dosing element causes liquid substances to be absorbed by the sponge-like body when the sponge-like body is moved relative to and in contact with the surface to be treated.

In a first embodiment, the receiving chamber is bounded by the dosing element and the surface of the sponge-like body, and the inflow opening is open as a result of a tilting movement of the dosing element, in particular as a result of a transverse movement of the sponge-like body on the surface to be treated. Delayed absorption of the substance from the receiving chamber through the sponge-like body can be achieved by the pores of the sponge-like body. By a certain amount of liquid substance being directly absorbed by the sponge-like body during filling of the receiving chamber, the amount of sponge-like body which enters the receiving chamber after each opening of the inflow opening is not sufficient, so that an optimum regulation of the substance absorbed by the sponge-like body is not achieved at all.

In the second embodiment, a better regulation of the amount of liquid substance absorbed is achieved. The characteristic is that the receiving chamber is bounded by the dosing element and the housing of the dosing element and is provided with an outflow opening, through which the liquid substance is supplied to the sponge-like body, the inflow opening being larger than the outflow opening and being opened by movement of the sponge-like body relative to the surface to be treated. By means of the substantially relatively narrow outflow opening and by means of the pores of the sponge-like body, it is further possible in this embodiment to achieve a delayed suction of the substance out of the receiving chamber by the sponge-like body.

In order to ensure that the receiving chamber is closed again after compression of the sponge-like body, the dosing element is movable against the action of a spring in a direction away from the treatment surface. In order to allow a suitable outflow of the liquid substance from the receiving chamber during operation of the device, there is a vent opening which is connected to the receiving chamber with a space between the receiving chamber and the sponge-like body. The gap is connected to the atmosphere via the sponge-like body.

From a constructional point of view it is advantageous if the outflow opening is formed by a gap between the housing of the receiving chamber and the dosing element extending therethrough. The gap is preferably annular.

Although one receiving chamber is sufficient, several, in particular two, receiving chambers are preferred depending on the size of the treatment surface. In order to keep the distance between the outer surface layer of the sponge-like body and the receiving chamber or chambers small, so that the liquid substance absorbed by the sponge-like body reaches the outer surface layer relatively quickly, on the other hand, the receiving chamber or chambers are at least partly placed in the sponge-like body, while, on the other hand, the thickness, density and structure of the sponge-like body are such that: there is a time delay between the outflow of the substance from the receiving chamber and the arrival of the liquid substance at the outer surface layer of the sponge-like body, which time delay corresponds to the time between two, in particular at least 6, successive device operation times. When the sponge-like body is moved, an outer layer of liquid substance which has been absorbed earlier by the sponge-like body is applied to the treated surface, while a new defined amount of liquid substance can be applied to the sponge-like body and absorbed therein with a delay. In this way, when using the device according to the invention, a quantity of liquid substance can always be applied from the sponge-like body to the treatment surface, which corresponds substantially to the quantity absorbed by the sponge-like body from the receiving chamber with a delay. As a result, the liquid substance is supplied very uniformly to the treatment surface and remains practically constant until the container is completely empty. In order to ensure that the above-mentioned time delay does not result in the device not being used properly immediately after purchase, and therefore that already a sufficient amount of liquid substance has been applied to the treated surface by the device a few first times, the sponge-like body is preferably impregnated with a substance, the composition of which does not need to be exactly the same as the substance in the container, after the device has been put into use, as will be further explained later on, in the outer surface layer.

In order to make it visible, the reservoir or at least part of the reservoir and preferably the container or part of the container are formed of a transparent substance, irrespective of whether and/or to what extent the container is filled. Disposed in a portion, preferably the upper portion, which forms the window. As long as the liquid substance, for example for the reasons mentioned below, is used for different specific colors, a device with the desired color can also be identified via the transparent reservoir or the window.

Although, the transparent material or selected portions of the window are suitable for the present invention, as described herein, the scope of application is also broad. The invention therefore also relates to a device for treating a surface, in particular a textile surface or a leather surface, such as, for example, the upper surface of leather shoes, with a liquid substance, which device comprises a holder with a reservoir for the substance and with a sponge-like body, through which substance absorbed from the reservoir can be spread on the surface, which device is characterized in that the holder or at least part of the holder and preferably the reservoir or a part thereof is made of a transparent material or is provided with a window. In this connection, in particular between the reservoir and the sponge-like body, there is held at least one receiving chamber which has an inflow opening communicating with the reservoir, which inflow opening is closed in the inoperative condition of the device and is simultaneously opened upon movement of the sponge-like body relative to the surface with which the sponge-like body is in contact, while the substance from the receiving chamber is absorbed by the sponge-like body with a delay.

In order to prevent the liquid substance from being subjected to an excessively high resistance on its way from the reservoir to the sponge-like body and still make the sponge-like body easy to use when the sponge-like body is moved relative to the treatment surface, the viscosity of the substance should on the one hand be sufficiently low that the substance can pass the inflow opening and on the other hand be sufficiently high that the substance does not leak from the sponge-like body when no force is exerted thereon. Preferably, the viscosity of the substance ranges from 1000 to 20000mm²sec^-1Preferably between 5000 and 12000mm²sec^-1In the meantime. Since there is a problem that it is not possible to very well select the viscosity appropriately in a particularly desired composition of the liquid substance, it is preferred that the viscosity of the substance changes after flowing out of the receiving chamber. In particular, if the substance contains an active ingredient with a relatively high viscosity, preferably greater than 5000mm²sec^-1In particular greater than 10000mm²sec^-1And an auxiliary component having a relatively low viscosity, preferably less than 5000mm²sec^-1In particular less than 2000mm²sec^-1By evaporation of the secondary component from the sponge-like body, the viscosity of the substance therein increases and leakage of the sponge-like body is prevented, while in any case the viscosity of the substance in the container is low enough to easily pass the receiving chamber. Resistance to the leakage of the substance from the sponge-like body is also easily achieved by reducing the pores of the sponge-like body; however, this is detrimental to the operation of the device according to the invention.

The above active ingredients can be used to make the treated surface shiny, protective, longer lasting, smoother, colored, etc. In a particular use of the treatment of the surface of leather, for example, the upper surface of leather shoes, the substance in the container comprises at least one first component which brightens the leather and also comprises at least one second component which enables the substance to be distributed on the surface of the leather. Such a substance can be advantageously used in the device according to the invention as described above, but also has a wide range of applications. As a result, the invention also relates to a device for treating a surface, in particular a leather substance, such as, for example, the upper surface of leather shoes, with a liquid substance, which device comprises a holder having a reservoir for the substance and having a sponge-like body, through which substance absorbed from the reservoir can be spread on the surface, which device is characterized in that the substance comprises at least one first component which brightens the leather and at least one second component having properties which enable the substance to be distributed on the leather surface.

In a particular embodiment, the first component consists of a polymer having a relatively high viscosity, preferably greater than 5000mm²sec^-1In particular greater than 10000mm²sec^-1And a second component consisting of polydimethylsiloxane, which may or may not be amino-functionalized, which has a low viscosity, preferably less than 5000mm²sec^-1In particular less than 2000mm²sec^-1. It is clear that by compounding these two components, better gloss balance and durability can be achieved. As a third component, a non-reactive amino-functionalized polydimethylsiloxane may be added to the material. In certain amino-functional polydimethyl silicones, adhesion of the substance to the leather is also facilitated. Thus, it is clear that by this addition, a better gloss balance and durability can be achieved. In this use, the viscosity of the material in the container was 500-²sec^-1In the meantime.

The viscosity must not be so high that the liquid substance is coated too thickly; likewise, the viscosity cannot be too low to obtain the desired gloss. The viscosity is also selected so that the substance is easily transported from the container and through the sponge-like body.

To provide coloration of the treated surface, pigments may be used. For this purpose, according to a further aspect of the invention, the pigment, in particular a water-soluble pigment, is provided in the sponge-like body, in particular at the bottom of the gap in the sponge-like body in which the receiving chamber is located, or the receiving chamber itself. It has been found that the pigment, in particular a water-soluble pigment, can be transported from the container to the outer surface layer of the sponge-like body by means of a fluid oily substance. By this addition, the treated surface can be dyed with the simultaneous application of gloss.

The paint may be dispersed in the substance contained within the container. Thus, a pigment dispersed in a polar solvent, such as an alcohol or ether, particularly a glycol ether, may be added to the substance in the container. It is also possible to add pigments dispersed in a non-polar solvent, such as white spirits, to the substance in the container.

To indicate which color is applied to the treatment surface by and/or with the aid of the substance in the container, a pigment representative of that color is added to the substance in the container. Thus, the colorant dissolved in the above-mentioned polar or non-polar solvent can be added to the substance in the container.

The invention will now be described in detail with reference to the accompanying drawings, in which:

drawings

Fig. 1 shows a first embodiment of the device according to the invention;

fig. 2 shows a second embodiment of such a device;

FIGS. 3A, 3B and 3C show a portion of the apparatus of FIG. 2 in successive steps in use of the apparatus; and is

Fig. 4 shows a third embodiment of the device according to the invention.

Detailed Description

Corresponding parts are designated by the same reference numerals in the figures.

The device according to the invention, as shown in fig. 1, comprises a holder 1, which holder 1 is formed by a lower box-shaped part 2 and an upper cover-shaped part 3. The two parts 2 and 3 are rectangular. The lower edge 4 of the lid-shaped part 3 is closed by a support 5. Located below the support 5 is a sponge-like body 6. The cover-shaped part 3 with the support 5 and the sponge-like body 6 form one piece, which is fitted on and in the box-shaped part 2, in which the sponge-like body 6 is located when the cover-shaped part is placed and clamped on the box-shaped part. When the device according to the invention is put into use, the cover-shaped part, the support and the sponge-like body are all detached from the box-shaped part.

The support 5 has a lower annular portion 7 to which the sponge-like body is fixed, in particular glued, and an upper portion 8, which delimits a container 9 for liquid substances. The upper edge of the container is formed by an upwardly projecting part 10 of the lid-shaped part 3. The upwardly projecting part 10 forms a window of transparent material so that it can be confirmed from the upper side of the device whether the container 9 still contains liquid substances. Furthermore, the support 5 comprises two hollow cylindrical portions 11 which extend vertically from the container 9 into the openings 12 of the void in the sponge-like body 6. The container 9 communicates with the interspace 14 in the cylindrical portion 11 via the opening 13; moreover, the container is completely closed by the support 5. The space 14 in the cylindrical part 11 is the passage of liquid substance from the space 14 to the receiving chamber 23'. The receiving chamber 23' is formed by the lower part of the interspace in the sponge-like body 6.

The void in the sponge-like body 6 has the shape of a cylindrical hole with a spherical lower end 15. In this bore, the dosing element 16 extends to practically abut against the lower end 15. The upper edge of the dosing element 16 is fixed to a protruding part 17 of the support 5 between the openings 13. More downwards, the dosing element 16 is provided with a closure 18 in the form of a frustoconical surface, which closure 18, in the rest condition, bears against the inner edge of the relative hollow cylindrical portion 11 and the inflow opening 19 of the receiving chamber 23' provided therebelow. The dosing element 16 is somewhat, i.e. it is intended that the dosing element 16 can be moved back and forth in the lateral direction. This movement can be achieved by the sponge-like body 6 moving back and forth with the lower surface against the contact surface; due to the deformations produced in the sponge-like body 6, the lower ends 15 of the holes move back and forth and the dosing element 16 moves with them. During this back and forth movement, the inflow opening 19 is opened on the one hand and the contents of the interspace 14 flow into the receiving chamber 23' at the bottom end of the bore and are then absorbed by the sponge-like body 6 with some delay.

By previously introducing a specific amount of liquid substance into the sponge-like body 6, it is possible to apply a layer of liquid substance directly to the treatment surface with the device already at the first moment or time by moving the sponge-like body back and forth over the treatment surface while applying some pressure. By doing so, the liquid substance is pressed out of the sponge-like body, after which the liquid substance collected in the receiving chamber 23' during the back and forth movement of the sponge-like body is absorbed by the sponge-like body as soon as the pressure drops or the device is no longer used. In this way, a very even distribution of the liquid substance in the sponge-like body can be continuously achieved with some delay until the container 9 is finally emptied. Now, the thickness, density and structure of the sponge-like body are such that: there is a time delay between the liquid substance flowing out through the inflow opening 19 and the substance reaching the outer surface layer of the sponge-like body 6, which time delay corresponds to the time between at least two and preferably at least 6 consecutive times of use of the device. This ensures that the device can be used for some time, even if the reservoir is just empty, until virtually all of the substance in the sponge-like body has been consumed. A small amount of material is always left in the sponge-like body.

The preferred embodiment in fig. 2 and 3A-C differs from the embodiment of fig. 1 in the design and manner of functioning of the receiving chamber and dosing element. The cylindrical part 11 extends less far into the relevant hole in the sponge-like body 6, but is provided at the lower side with a sleeve-shaped part 20, which sleeve-shaped part 20 is approximately conical in the downward direction and converges, passing the converging dosing element 21, to the vicinity of the lower end 15 of the hole. Here, the conical portion 22 of the sleeve-shaped portion 20 forms the boundary of the receiving chamber 23, and the outflow opening 24 in the form of an annular gap forms a permanent connection between the relevant receiving chamber 23 and the interspace at the bottom of the bore in the sponge-like body 6. Here too, the receiving chamber 23 is completely located in the sponge-like body 6. The dosing element 21 is provided at the upper side with a widened portion 25, which is provided with a cylindrical joint 26 for a spring 27, which spring 27 is movable between the support 5, i.e. the portion thereof surrounding the opening 13, and the dosing element 21. At the lower side of the widened portion 25, there is a shell-shaped part 28 which is open at the lower side. The shell 28 and the widened portion 25 form an upper boundary of the receiving chamber 23. In the rest condition, the spring 27 holds the dosing element 21 in a lowermost position, which is a position in which the shell 28 bears against the conical portion 22 and the inflow opening 29 of the receiving chamber 23 between the shell 28 and the conical portion 22 is closed. Located in the conical portion 22 is a circular-arc-shaped ventilation opening 30, which ventilation opening 30 communicates with the receiving chamber 23 with a clearance at the bottom of the associated hole in the sponge-like body 6.

The operation of the device shown in fig. 2 is explained with reference to fig. 3A-C. These figures show that the dosing means has only one opening in the sponge-like body 6. Fig. 3A shows the rest condition, in which the spring 27 keeps the dosing element 21 in its lowermost position and the receiving chamber 23 is empty and closed at the top. Through the opening 13, the space 31 above the dosing element 21 is filled with liquid substance from the container 9. Fig. 3B shows the sponge-like body 6 in a position in which it is compressed against the surface to be treated. By this compression, the dosing element 21, which is in contact with the lower end 15 of the hole in the sponge-like body 6, moves upwards against the spring 27 and the inflow opening 29 of the receiving chamber 23 is opened, so that the chamber is filled with liquid substance from the interspace 31. As soon as the pressure on the sponge-like body 6 is removed, the dosing element 21 is moved downwards under the influence of the spring 27 and the receiving chamber 23 is closed again at the upper side. This position is shown in fig. 3C. As previously mentioned, the receiving chamber 23 is in continuous open communication with the interspace at the bottom of the hole in the sponge-like body 6 via the gap 24. According to the fact that: the inflow opening 29 of the receiving chamber 23 is much larger than the outflow opening 24 (see fig. 3B), the receiving chamber fills up quickly and virtually no liquid substance can seep out through the outflow opening 24. In a later time, when the device is not in use, a defined amount of liquid substance in the receiving chamber 23 can be absorbed by the sponge-like body 6 through the outflow opening 24 and the space at the bottom of the well. According to the fact that: each time the sponge-like body absorbs a defined amount, this example makes it possible to achieve a further regulated flow of liquid substance through the sponge-like body, when compared with the embodiment of fig. 1. Yet another way in which the apparatus shown in figures 2 and 3A-C operates is the same as that of the embodiment shown in figure 1.

The size of the receiving chamber 23 and the size of the inflow and outflow openings 29 and 24, as well as the thickness, density and structure of the sponge-like body 6, must be adjusted to the viscosity of the liquid substance. The specific design of the device according to the invention is therefore very dependent on the use, that is to say the result produced by the liquid substance.

The embodiment shown in fig. 4 corresponds substantially to the embodiment shown in fig. 2. However, there is only one receiving chamber 23 between the reservoir 9 and the sponge-like body 6. Instead of the cylindrical portion 11, a slightly tapered portion 11 'is provided, while the void 9 is integral with the void 14 in the slightly tapered portion 11'. The lower end of the portion 11' has the same shape as the sleeve-shaped portion 20 in fig. 2, while it is understood that a sealing lip 34 is provided to prevent liquid substance from leaking from the interspace 14 to the receiving chamber 23 in the rest condition. Furthermore, the spring 27, the junction point of the coupling 26 and the abutment point on the support 5 are replaced by a leaf spring arrangement, the leaf spring 27' being connected at one end to the dosing element 21 and at the other end to the cap-shaped portion 3. In the opening 12 there is also arranged a protection which ends at the lower edges of the converging lips. The operation of this embodiment may also be the same as that of the embodiment shown in fig. 2.

The shown embodiment is suitable for liquid substances with which a lightening effect can be achieved on leather, for example for polishing leather shoes. To this end, the liquid substance that can be applied to the upper side of leather shoes by means of the device according to the invention comprises a first component that brightens the leather and a second component that enables the liquid substance to spread onto the leather. The first component is composed of a first component having a thickness preferably greater than 10000mm²sec^-1And the second component consists of a more volatile polydimethylsiloxane having a viscosity of less than 2000mm²sec^-1. To achieve good adhesion, a non-reactive amino-functional polydimethylsiloxane is added to the material. In combination with the dimensioning and design of the device, the viscosity of the substance, i.e. the mixed product, is 500-²sec^-1Between the ranges. For the simultaneous coloring of the leather, the bottom of the voids in the sponge-like body 6 is provided with a water-dispersible pigment. In the use of the device according to the invention, the paint is delivered to the sponge-like body 6 by means of a substance from the reservoir 9, that is to say by means of an oil delivery mediumAn outer surface layer. This measure is combined with the spreading of the pigment in the substance contained in the container. Alternatively, it is of course also possible to add pigments dispersed in polar solvents, such as alcohols or ethers, in particular glycol ethers, or in nonpolar solvents, such as white spirits, to the substance in the container. Furthermore, to indicate the pigment colour, a colouring agent added to a suitable solvent is added to the substance in the container. Alternatively, although somewhat less efficient, i.e. by means of a roller mechanism, the pigment dispersed in the silicone oil-is volatile-free and has a thickness of about 10000 to 15000mm²sec^-1Is filled in the outer layer, that is to say in the lowermost layer of the sponge-like body in the figure. The oil will then hold about 1-5% pigment; too much pigment reduces the gloss obtained.

The invention is not limited to the embodiments described herein with reference to the drawings; it includes all the forms of modification, i.e. of the structure of the device and of the composition of the liquid substances, provided, of course, that they are contained within the scope of protection of the appended claims.

Claims (29)

1. A device for treating a surface, including a textile surface or a leather surface, with a liquid substance, which device comprises a reservoir having a reservoir for such substance and a sponge-like body through which the substance sucked from the reservoir can be dispersed onto the surface, characterized in that at least one receiving chamber is provided between the reservoir and the sponge-like body, which receiving chamber has an inflow opening communicating with the reservoir, which inflow opening is closed in the rest condition of the device and can be opened upon movement of the sponge-like body relative to a plane in which the sponge-like body comes into contact, while substance is sucked from the receiving chamber by the sponge-like body with a delay.

2. Device according to claim 1, characterized in that the dosage value of the liquid substance from the receiving chamber is between 0.01 and 3ml each time the receiving chamber is filled via the inflow opening.

3. A device as claimed in claim 1, characterized in that a dosing element projects into the receiving chamber, which dosing element has the effect that liquid substances can be absorbed by the sponge-like body when the sponge-like body is moved relative to and in contact with the surface to be treated.

4. Device as claimed in claim 1, characterized in that the receiving chamber is bounded by the dosing element and the surface of the sponge-like body, and in that the tilting movement of the dosing element opens the inflow opening as a result of a transverse movement of the sponge-like body over the surface to be treated.

5. Device as claimed in claim 1, characterized in that the receiving chamber is bounded by the dosing element and a housing of the dosing element and is provided with an outflow opening, through which the liquid substance is supplied to the sponge-like body, which inflow opening is larger than the outflow opening and which inflow opening can be opened by movement of the sponge-like body relative to the surface to be treated.

6. A device as claimed in claim 5, characterized in that the inflow opening can be opened by moving the dosing element away from the surface to be treated, as a result of the sponge-like body compressing onto the surface to be treated.

7. A device as claimed in claim 6, characterized in that the dosing element is movable against the action of a spring in a direction away from the surface to be treated.

8. A device as claimed in claim 5, characterized in that a ventilation opening is present, which is connected to the receiving chamber and has a clearance between the receiving chamber and the sponge-like body.

9. A device as claimed in claim 5, characterized in that a gap between the housing of the receiving chamber and the dosing element extending therein forms the outflow opening.

10. The apparatus of claim 9 wherein the gap is annular.

11. The device of claim 1, wherein there are a plurality of receiving chambers.

12. A device as claimed in claim 11, characterized in that the receiving chamber or chambers are arranged at least partially in the sponge-like body.

13. The device of claim 1, wherein the thickness, density and structure of the sponge-like body are such that: there is a time delay between the outflow of the substance from the outflow opening and the arrival of the liquid substance at the outer surface layer of the sponge-like body, which time delay corresponds to the time between at least two successive device operation times.

14. A device according to claim 13, wherein the sponge-like body is impregnated with a liquid substance before the device is put into use.

15. A device as claimed in claim 1, characterized in that the reservoir or at least a part of the reservoir is formed by a transparent substance or is provided with a window.

16. A device according to claims 1-15, characterized in that the viscosity of the substance is on the one hand sufficiently low for the substance to pass the inflow opening and on the other hand sufficiently high for the substance not to leak from the sponge-like body in the absence of an applied force thereon.

17. The device of claim 16, wherein the substance changes viscosity after flowing out of the receiving chamber.

18. An apparatus according to claim 16, wherein the substance has a viscosity in the range of 500 to 20000mm²sec^-1In the meantime.

19. Device according to claim 16, characterised in that the substance contains an active ingredient with a higher viscosity, which is greater than 5000mm²sec^-1And an auxiliary component having a lower viscosity of less than 5000mm²sec^-1。

20. An apparatus according to claim 16, characterized in that the surface of the leather, including the upper surface of the leather shoes, is treated, the substance in the container comprising at least one first component for smoothing the leather and at least one second component having properties enabling the substance to be distributed over the surface of the leather.

21. The apparatus of claim 1, wherein the leather surface comprises a top surface of a leather shoe.

22. The device of claim 2, wherein the dose value is between 0.05 and 1 ml.

23. The apparatus of claim 22, wherein the dose value is 0.1 ml.

24. The device of claim 11, wherein the receiving chambers are two.

25. The apparatus of claim 13 wherein the time delay corresponds to at least a time between at least 6 consecutive device operation times.

26. The device of claim 18, wherein the substance has a viscosity in the range of 500 and 9000mm²sec^-1In the meantime.

27. The apparatus of claim 19, wherein the relatively high viscosity is greater than 10000mm²sec^-1。

28. The device of claim 19, wherein the relatively low viscosity is less than 2000mm²sec^-1。

29. A device according to claim 15, wherein the container or part thereof is formed of a transparent material or is provided with a window.