Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – For cleaning a specific substrate or removing a specific...
Reexamination Certificate
2000-07-26
2002-10-08
Douyon, Lorna M. (Department: 1751)
Cleaning compositions for solid surfaces, auxiliary compositions
Cleaning compositions or processes of preparing
For cleaning a specific substrate or removing a specific...
C510S298000, C510S446000, C134S025200
Reexamination Certificate
active
06462007
ABSTRACT:
TECHNICAL FIELD
The present invention relates to detergent tablets having multiple layers.
BACKGROUND OF THE INVENTION
Detergent compositions in tablet form are known in the art. Detergent compositions in tablet form hold several advantages over detergent compositions in particulate or liquid form, such as ease of handling, transportation and storage. Due to these advantages, detergent compositions in tablet form are becoming increasingly popular with consumers of detergent products.
Detergent tablets are most commonly prepared by pre-mixing the components in the composition and forming the pre-mixed components into a tablet via the use of a tablet press and compression of the components. However, traditional tablet compression processes have significant drawbacks, including but not limited to the fact that selected components of a detergent composition may be adversely affected by the Compression pressure in the tablet press. Accordingly, these selected components were not typically included in prior art detergent tablets without sustaining a loss in performance. In some cases, these selected components may even have become unstable or inactive as a result of the compression.
In addition, as the components of the detergent composition are compressed in the tablet press, they are brought into close proximity with one another resulting in the reaction of selected component, instability, inactivity or exhaustion of the active form of the components.
To avoid the above mentioned drawbacks, prior art detergent tablets have attempted to separate components of the detergent composition that may potentially react with each other when the detergent composition is compressed into tablet form. Separation of the components has been achieved by, for example, preparing multiple-layer tablets wherein the reactive components are contained in different layers of the tablet or encapsulation and coating of reactive components. These prior art multiple-layer tablets are traditionally prepared using multiple compression steps. Accordingly, layers of the tablet which are subjected to more than one compression step may be subjected to a cumulative and potentially greater overall compression pressure. In addition, an increase in compression pressure of the tabletting press is known to decrease the rate of dissolution of the tablet with the effect that such multiple layer tablets may not dissolve satisfactorily in use.
Accordingly, the need remains for an improved detergent tablet which can deliver active detergent ingredients to a domestic wash process thereby delivering superior performance benefits.
SUMMARY OF THE INVENTION
This need is met by the present invention wherein a detergent tablet having a core, a first encapsulating layer, and a second encapsulating layer is provided. The tablet of the present invention delivers detergent components previously considered to be unacceptable for detergent tablets in addition to effectively separating potentially reactive ingredients. In addition, the detergent tablet of the present invention provides superior cleaning performance, particularly in domestic automatic dishwashing machines over the tablets of the prior art.
According to a first embodiment of the present invention, a detergent tablet is provided. The tablet comprises a multi-layered detergent tablet comprising:
a) a core having a first detergent active agent;
b) a first encapsulating layer surrounding said core, having a second detergent active agent, and optionally a disruption system;
c) a second encapsulating layer surrounding said first encapsulating layer, having a third detergent active agent and a disruption system;
wherein disruption of said second encapsulating layer is such that at least 25%, preferably, 35%, more preferably 45%, even more preferably still 50%, of said third detergent active agent is released prior to release of said second detergent active agent, and when first encapsulating layer contains the optionally preferred disruption system, disruption of said first encapsulating layer is such that at least 25%, preferably, 35%, more preferably 45%, even more preferably still 50%, of said second detergent active agent is released prior to release of said first detergent active agent.
According to a second embodiment of the present invention, a detergent tablet is provided. The tablet comprises a multi-layered detergent tablet comprising:
a) a core having a first detergent active agent;
b) a first encapsulating layer surrounding said core, having a second detergent active agent and optionally a disruption system;
c) a second encapsulating layer surrounding said first encapsulating layer, having a third detergent active agent and a disruption system;
wherein disruption of said second encapsulating layer is such that said third detergent active agent is released at least 2 minutes, preferably at least 3 minutes, more preferably at least 5 minutes, even more preferably still at least 10 minutes, prior to release of said second detergent active agent.
According to a third embodiment of the present invention, a detergent tablet is provided. The tablet comprises a multi-layered detergent tablet comprising:
a) a core having a first detergent active agent;
b) a first encapsulating layer surrounding said core, having a second detergent active agent and optionally a disruption system;
c) a second encapsulating layer surrounding said first encapsulating layer, having a third detergent active agent and a disruption system;
wherein disruption of said second encapsulating layer occurs in an aqueous cleaning environment at a temperature of 25° C. or less, preferably 15° C. or less, more preferably 10° C. or less and wherein release of said second detergent active agent occurs in an aqueous cleaning environment at a temperature of 30° C. or greater, preferably 35° C. or greater, more preferably 40° C. or greater.
According to a fourth embodiment of the present invention, a method of washing tableware is provided. The method comprises a washing tableware in a domestic automatic dishwashing appliance, said method comprising treating the soiled tableware in an automatic dishwasher with a multi-layered detergent tablet according to any of the previous embodiments.
Accordingly, it is a further aspect of the present invention to provide a multi-layered detergent tablet which can quickly and efficiently deliver detergent actives to a domestic wash process. These, and other aspects, features and advantages of the present invention will be readily apparent to one of ordinary skill in the art from the following detailed description and the appended claims.
All percentages, ratios and proportions herein are by weight, unless otherwise specified. All temperatures are in degrees Celsius (° C.) unless otherwise specified. All documents cited are in relevant part, incorporated herein by reference.
Definition
“Encapsulating” as used herein means that the layer surrounds totally or encases the previous layer or core. That is, the layer or core which is encapsulated and the detergent active agents in these have no direct access to the outside environment. Access to the outside environment can only happen when the encapsulating layer is removed, either partially or in totality, such as would occur in an aqueous washing environment. For example the second encapsulating layer surrounds totally the first encapsulating layer and none of the second detergent active agent is released until the first encapsulating layer has direct access to the outside environment. This occurs either after a set time or after a quantity of the third detergent active agent has been released.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention comprises a multi-layered detergent tablet and in particular a detergent tablet for automatic dishwashing which has a core, a first encapsulating layer and a second encapsulating layer.
Accordingly, by way of the present invention, detergent active components of a detergent tablet previously adversely affected by the compression pressure used to form the tablets may now be i
Foley Peter Robert
Pieroni Lucio
Song Xiaoqing
Speed Lynda Anne
Douyon Lorna M.
The Procter & Gamble & Company
Waugh Kevin L.
LandOfFree
Multi-layer detergent tablet does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multi-layer detergent tablet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-layer detergent tablet will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2953323