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Title:
TOOTH WHITENING SYSTEM INCLUDING A TOOTH WHITENING COMPOSITION AND AN ACTIVATOR THEREFOR
Document Type and Number:
WIPO Patent Application WO/2014/107164
Kind Code:
A1
Abstract:
A tooth whitening system for whitening a user' s teeth with chlorine dioxide which penetrates a user' s tooth enamel and removes stains from a user' s teeth includes a tooth whitening composition for being applied to the user' s teeth that includes a tooth whitening compound. The tooth whitening compound includes sodium chlorite, and there is an acidic activator for being applied to a user's teeth for activating the sodium chlorite by converting the sodium chlorite to active chlorine dioxide when the acidic activator contacts the sodium chlorite on the tooth enamel of the user's teeth, thereby removing stains from the user's teeth. The acidic activator may include one of phosphoric acid and citric acid. There is likewise a dispenser for dispensing a tooth whitening composition and an activator composition, concurrently or sequentially, for activating the whitening compound in the whitening composition concurrently or sequentially.

Inventors:
BROWN DAMON (US)
ALI ARSHAD (CA)
Application Number:
PCT/US2013/020373
Publication Date:
July 10, 2014
Filing Date:
January 04, 2013
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
DENTOVATIONS INC (US)
International Classes:
A61K8/20; A61Q11/02
Foreign References:
US5944528A1999-08-31
US20070254260A12007-11-01
US4330531A1982-05-18
US20100015252A12010-01-21
US20100086499A12010-04-08
Attorney, Agent or Firm:
BROWN, Terrence L., B. (ARKWRIGHT & GARVEY LLP5845 Richmond Highway, Suite 41, Alexandria VA, US)
Download PDF:
Claims:
CLAIMS :

1. A tooth whitening system for whitening a user' s teeth with chlorine dioxide which penetrates a user' s tooth enamel and removes stains from a user's teeth, the tooth whitening system comprising:

a) a tooth whitening composition for being applied to the user's teeth, the tooth whitening composition including a tooth whitening compound;

b) the tooth whitening compound including sodium chlorite; and

c) an acidic activator for being applied to a user's teeth for activating the sodium chlorite by converting the sodium chlorite to active chlorine dioxide when the acidic activator contacts the sodium chlorite on the tooth enamel of the user's teeth, thereby removing stains from the user's teeth.

2. A tooth whitening system for whitening a user' s teeth as in claim 1, wherein:

a) the acidic activator includes phosphoric acid.

3. A tooth whitening system for whitening a user's teeth as in claim 1, wherein:

a) the acidic activator includes citric acid.

4. A tooth whitening system for whitening a user' s teeth as in claim 1, wherein:

a) the tooth whitening composition includes the following formula by weight percent:

i) water 98.1; and

ii) sodium chlorite 1.9.

5. A tooth whitening system for whitening a user's teeth as in claim 1, wherein:

a) the tooth whitening composition includes the following formula in weight percent:

i) water 98.125; and

ii) sodium chlorite 1.875. 6. A tooth whitening system for whitening a user's teeth as in claim 4, wherein:

a) the activator composition includes the following formula in weight percent:

Water

Propylene Glycol

Xylitol

Xanthan-Gum

Sodium Benzoate

Mentha Piperita

(Peppermint) Oil

Phosphoric acid

Water

Titanium Dioxide

Disodium EDTA

7. A tooth whitening system for whitening a user's teeth as in claim 1, wherein:

a) the tooth whitening composition includes the following formula in weight percent:

Water 62.750

Hydroxyethylcellulose 0.750

Sodium Carbonate 0.500

Sodium Chlorite 0.500

Potassium Pyrophosphate 0.500

PEG/PPG-20/15 Dimethicone 0.500

Alcohol Dent 7.500

Hydrated Silica 27.000

8. A tooth whitening system for whitening a user's teeth as in claim 1, wherein: a) the tooth whitening composition includes the following formula in weight percent:

Water 87.930

Sodium Chlorite 1.870

PEG/PPG- 116-66 Copolymer 10.000

Sodium Hydroxide 0.200

9. A tooth whitening system for whitening a user's teeth in claim 1, wherein: a) the tooth whitening composition includes the following formula in weight percent:

Deionized 94.8

(DI) Water

Sodium 5.0

Chlorite

SF1188A 0.2

10. A tooth whitening system for whitening a user's teeth as in claim 9, wherein: a) the activator composition includes the following formula in weight percent:

Deionized (DI) Water 92.83

Propylene Glycol 5.00

Germaben II ® 0.15

Xanthan Gum 0.5

Peppermint oil 0.35

NutraSweet ® 0.3

EDTA H4 0.37

Phosphoric acid 85% As needed to pH 4-4.3 -0.5

parts

11. A tooth whitening system for whitening a user's teeth as in claim 1, wherein: a) the activator composition includes the following formula in weight percent :

Deionized (DI) Water 92.83

Propylene Glycol 5.00

Germaben II ® 0.15

Xanthan Gum 0.5

Peppermint oil 0.35

NutraSweet ® 0.3

EDTA H4 0.37

Phosphoric acid 85% As needed to pH 4-4.3 -0.5

parts

12. A tooth whitening system for whitening a user' s teeth as in claim 1, wherein: a) a dispenser is provided including a container for containing the whitening composition further container for containing the acidic composition; b) the container and further container include respective valves and a mixing region provided

adjacent thereto; and

c) the container and further container are sufficiently flexible so that the user can squeeze the container and further container to reduce the volumes thereof to force out the respective whitening

composition and the activating composition through the respective valves for mixing the whitening composition and the activating composition together in the mixing region before applying the whitening composition and the activating composition to the user's teeth.

13. A tooth whitening system for whitening a user's teeth in claim 1, wherein:

a) a dispenser is provided including a

container for containing the whitening

composition further container for containing the acidic composition;

b) the container and further container include respective valves and a mixing region provided adjacent the respective valves; and

c) the container and further container include an actuator so that the user can activate the actuator to force out the whitening composition and the activating composition from the container and further container through the respective valves for mixing the whitening composition and the activating composition together in the mixing region before applying the whitening composition and the activating composition to the user's teeth.

14. A tooth whitening system for whitening a user's teeth claim 13, wherein:

a) the actuator is configured so that the user can activate the actuator to concurrently force out the whitening composition and the activating composition from the container and further container through the respective valves for mixing the whitening composition and the activating composition together in the mixing region before applying the whitening composition and the activating composition to the user's teeth.

Description:
TOOTH WHITENING SYSTEM INCLUDING

A TOOTH WHITENING COMPOSITION AND AN ACTIVATOR THEREFOR

FIELD OF THE INVENTION

The invention relates to a tooth whitening system, including a tooth whitening composition, an activator for activating a tooth whitening compound in the tooth whitening composition, in particular an acidic activator therefor, and method of using the tooth whitening system.

BACKGROUND OF THE INVENTION

Tooth whitening compositions are known, such as tooth whitening toothpastes and compositions available to individuals for being used by themselves, as well as tooth whitening compositions available only when administered by dental care professionals, such as dentists.

Tooth whitening compositions often have a shorter than desired shelf life given that the tooth whitening compound and the tooth whitening compositions have a tendency to chemically degrade over time.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the invention to overcome the drawbacks of the prior art. It is another object of the invention to overcome the drawbacks of known tooth whitening compositions, tooth whitening compounds, and tooth whitening toothpastes administered by individual users, and by dental professionals administering the tooth whitening compositions on the user's teeth.

It is a further object of the invention to provide a stabilized tooth whitening composition to extend the shelf life of professional and non-professional tooth whitening

compositions .

It is a further object of the invention to reduce or substantially eliminate the degradation of whitening compounds present in tooth whitening compositions, so that a container, such as a toothpaste tube in which the composition is provided, does not expand over time owing to the release of a breakdown compound from the degraded compound, such as a gas; e.g., oxygen from hydrogen peroxide during the decomposition from 2 H2O2 ~ 2 H 2 0 + 0 2 .

It is another object of the invention to reduce or

substantially eliminate the degradation of whitening compounds present in tooth whitening compositions, so that a container, such as a toothpaste tube in which the composition is provided, does not expand over time owing to the release of a breakdown compound from the degraded compound in a tooth whitening

composition, such as during decomposition; i.e., the oxidation of sodium chlorite to yield C102 : 2 NaC102 + C12 -> 2 C102 + 2 NaCl .

It is a further object of the invention to provide an alternative to the use of hydrogen peroxide in whitening

compositions present in tooth whitening compositions, so that a container, such as a toothpaste tube in which the composition is provided, does not expand over time owing to the release of a breakdown compound from the degraded hydrogen peroxide, such as a gas; e.g., oxygen from the decomposition of the hydrogen peroxide. Such thus avoids the "problem" of tubes of tooth- whitening toothpaste having gas build-up over time that leads to tighter (i.e., tauter) tubes of hydrogen peroxide containing tooth-whitening toothpastes that to some consumers are

unexpected and, hence, undesirable.

It is a further object of the invention to replace the use of hydrogen peroxide as a whitening compound by providing a tooth-whitening composition including sodium chlorite as the compound by which the desired tooth-whitening is achieved.

The invention set forth herein has achieved these and other objects of the invention by providing a tooth whitening

composition, such as toothpastes, including tooth whitening compounds, along with an activator compound in an activator composition to achieve a stabilized product in order to achieve a longer shelf life. The invention set forth herein has achieved these and other objects of the invention by providing tooth whitening compounds, and tooth whitening compositions, such as toothpastes, along with an activator compound in an activator composition to achieve a stabilized product in order to achieve a longer shelf life, without the use of hydrogen peroxide.

The invention further includes, comprises, consists

essentially of, or consists of a tooth whitening composition and system in the form of a tooth whitening composition and an activator composition for activating a tooth whitening compound therein at the time when the user's teeth are to be whitened.

The invention further includes, comprises, consists

essentially of, or consists of tooth whitening compositions, such as toothpastes, along with an acidic activator compound in an activator composition as set forth herein.

The invention further includes the method of making the tooth whitening compositions and the respective tooth whitening compounds with activator compounds and compositions as set forth herein .

The invention further includes a dispenser for dispensing one or both of the tooth whitening composition and activator composition at the same time, substantially the same time, or at different times, for activating a tooth whitening compound and whitening the user' s teeth when the tooth whitening composition and activator composition are dispensed thereon.

The invention further includes a tooth whitening system for whitening a user' s teeth with chlorine dioxide which penetrates a user's tooth enamel and removes stains from a user's teeth, the tooth whitening system having a tooth whitening composition for being applied to the user' s teeth including a tooth

whitening compound, such as sodium chlorite. There is an acidic activator for being applied to a user' s teeth for activating the sodium chlorite by converting the sodium chlorite to active chlorine dioxide when the acidic activator contacts the sodium chlorite on the tooth enamel of the user's teeth, thereby removing stains from the user's teeth.

The invention further includes that the acidic activator is phosphoric acid.

The invention further includes that the acidic activator is citric acid.

The invention further includes that the tooth whitening composition includes the following formula by weight percent:

i) water 98.1; and

ii) sodium chlorite 1.9.

The invention further includes that the activator

composition includes phosphoric acid. The invention further includes a dispenser is provided which dispenses the whitening composition and the activating composition concurrently or successive onto the user's teeth.

The invention further includes that the dispenser includes one or more tubes including respective actuators, such as pistons, so that the user can use the actuator to reduce the volume of one or more of the tubes containing the respective one of the whitening composition and the activating composition to force the respective compositions through a respective valve for mixing the compositions together before or after applying the compositions to the user's teeth.

Relative terms, such as left, right, up, and down are for convenience only and are not intended to be limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a partially broken away top plan view of a dispenser 100 for dispensing a tooth whitening composition W and an activator composition A in accordance with an embodiment of the invention;

Fig. 2 is a partially broken away top plan view of a dispenser 200 for dispensing a tooth whitening composition W and an activator composition A concurrently in accordance with a further embodiment of the invention; Fig. 3 is a side view of dispenser 200 of the further embodiment of Fig. 2 in accordance with the invention; and

Fig. 4 is a front partially broken away view of a dispenser 300 for dispensing a tooth whitening composition W from a container 304 and a further container 308 for dispensing an activator composition A concurrently in accordance with a still further embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention described herein, including the Trade Names and INCI (International Nomenclature of Cosmetic Ingredients) set forth herein will be readily understood by a person having ordinary skill in the art.

The following formulas set forth applicant's inventive tooth whitening compositions, such as toothpastes in which sodium chlorite is the tooth whitening compound, and there is an activator, such as an acidic activator, e.g., phosphoric acid or citric acid, as set forth herein, as will be readily understood by a person having ordinary skill in the art.

Further, the invention includes the whitener compositions and activator compositions, such as set forth below in the various Tables showing various embodiments of the whitener and activator compositions formulas according to the invention. Whitener Composition Embodiment 1 Whitener Composition 1

Formula No. Dento W- 09-12-1 Description: Whitener: Sodium Chlorite Sol (Step 1)

Activator composition embodiment 1 may include a

stabilizer, such as sodium benzoate, as set forth in the table below :

Activator Composition Embodiment 1

Activator Composition 1

Formula No. Dento W-09-12-2 Description: Activator Gel (Step 2)

Trade/Ingredient/ ttNCI INECS/ % RI in

Chemical Name (RI) 1(Sub-ingredient; SI) CAS # LINCS % SI in RI Formula Source Function

Water Water 7732-18-5 231-791-2 100.00 92.850 Natural Solvent

Propylene Glycol Propylene Glycol 57-55-6 200- 338-0 100.00 5.000 Synthetic Solvent Xylitol NF FCC Xylitol 87-99-0 201- 788-0 100.00 0.750 Synthetic Sweetener VanzanNF Xanthan-Gum 11138-66-2 234-394-2 100.00 0.550 Natural Thickener

Sodium Benzoate NF Sodium Benzoate 532-32-1 208-534-8 100.00 0.350 Synthetic Preservative Peppermint Oil Mentha Piperita 8006-90-* NA 100.00 0.200 Natural Flavor (Redistilled) (Peppermint) Oil

Phosphoric acid (85%) Phosphoric acid 7664-38-2 231-633-2 85.00 0.150 Synthetic pH adjuster

Water 7732-18-5 231-791-2 15.00 Natural Solvent

Titanium Dioxide Titanium Dioxide 13463-67-7 236-675-5 100.00 0.100 Mineral Colorant ProtachemNA-2-P Disodium EDTA 139-33-3 205-358-3 100.00 0.050 Synthetic stabilizer

Total 100.000

The EINECS (European Inventory of Existing Commercial

chemical Substances) number is the assigned number in a European identification system similar to the INCI and CAS# system, as will be readily appreciated by a person having ordinary skill in the art. The EINICS numbers are available at, e.g., http : //esis . j rc . ec . europa . eu/index .php?PGM=ein .

Further Whitener Composition Embodiment 2

Whitener Composition Embodiment 2

Product No. Description: Whitening system- 1

Item

Part # Trade Name INCI Weight (%)

Purified water Water 62.750

Cellulose gum Hydroxyethylcellulose 0.750

Sodium Carbonate Sodium Carbonate 0.500

Sodium Chlorite Sodium Chlorite 0.500

Potassium Pyrophosphate Potassium Pyrophosphate 0.500

SF 1180 SI PEG/PPG-20/15 Dimethicone 0.500

SDA 38B-190 Alcohol Dent 7.500

Hydrated Silica Hydrated Silica 27.000

Total 100.000

Hydroxyethylcellulose is also known by its lUPAC Name as

Cellulose, 2-hydroxyethyl ether, and by CAS number 9004-62-0.

Whitener composition embodiment 2 is formulated to be us with activator embodiment 1, for example, that it can be dispensed like a toothpaste, such as with the dispenser embodiment 200 described in connection with Fig. 2 below. Further, it is formulated for daily use as a whitening toothpaste .

Still Further Whitener Composition Embodiment 3

Embodiment of Whitener Composition Embodiment 4 and

Activator Composition Embodiment 2

The whitener composition embodiment 4 and the activator composition embodiment 2 may be used together for whitening teeth . This is a formulation of a non-peroxide tooth whitening system according to the invention. This whitening system includes a chlorite salt to be applied to the tooth surface and then an acid gel to activate the chlorite salt. This whitening system thus generates chlorine dioxide, which is the compound which whitens teeth.

Formulation of Whitener Composition Embodiment 4

Part A Sodium Chlorite solution

In whitener composition embodiment 4 the SF1188A (INCI name: PEG/PPG-20/15 Dimethicone) silicone fluid is a stable copolymer of a polydimethylsiloxane (PDMS) and a polyoxyalkylene ether .

In order to prepare whitener composition embodiment 4 (Part A) the sodium chlorite and the SF1188A are added to the deionized water.

Formulation of Activator Composition Embodiment 2

Part B Activator solution

Component Parts by weight

Deionized (DI) Water 92.83

Propylene Glycol 5.00

Germaben II ® 0.15

Xanthan Gum 0.5

Peppermint oil 0.35 NutraSweet ® 0.3

EDTA H4 0.37

Phosphoric acid 85% As needed to pH 4-4.3 -0.5

parts

Germaben II ® is a trademark of International Specialty Products, a subsidiary of Ashland Inc., Covington, Kentucky, United States of America (US) . Germaben II includes: 30% Germall® II, 11% Methylparaben, 56% Propylene glycol, 3%

Propylparaben. The INCI for Germall® II is diazolidinyl urea.

NutraSweet ® is a trademark of The NutraSweet Company, a subsidiary of J.W. Childs Associates, Chicago, Illinois, The United States of America (US) .

In order to prepare the activator composition embodiment 2 (Part B) the xanthan gum and propylene glycol are mixed and then set aside. All ingredients are added to the water except phosphoric acid. When ingredients are mixed the xanthan gum/propylene glycol are added and mixed. The phosphoric acid is added in small increments to bring activator embodiment composition 2 to a pH of 4-4.3 ads will be readily appreciated by a person having ordinary skill in the art.

The activator composition according to the invention may include an acidic activator. The acidic activator may be phosphoric acid, which may be used in the inventive activating composition. The activating composition may be a liquid, such as in the form of a gel, and may be termed an activator gel.

The activator gel may be formulated with citric acid in place of phosphoric acid as the acidic activator for the

activating composition in accordance with the invention.

The sodium chlorite in the whitener composition may be applied to the tooth to be whitened by applying a mouth rinse or by painting on the whitener composition, or by some other means. Then, the activator composition may be applied by the user or by the dental professional likewise by applying an activator mouth rinse or by painting on the activator composition, or by some other means of applying the activation composition to the teeth.

Then, the thus activated whitening compound, such as the sodium chlorite, is converted to active chlorine dioxide (C102) which then penetrates the user's or patient's enamel and most types of stains are removed (e.g., "lifted") from the surface of the treated tooth. That surface includes the outermost enamel layer and stains in the dentin adjacent the enamel.

Sodium Chlorite is more stable that hydrogen peroxide.

Hydrogen peroxide is comparatively more reactive and typically has a shorter shelf life (12-15 month) as compared to sodium chlorite (36 months) . Formulation of Activator Composition Embodiment 3

Activator solution

Activator composition embodiment 3 can be prepared in

manner similar to the preparation of activator composition

embodiment 2 above, yet with citric acid used in place of

phosphoric acid.

Activator Composition Embodiment 4

Activator Composition 4

Formula No. Description: Activator Gel (Step 2)

Trade/Ingredient/ ttNCI INECS/ % RI in

Chemical Name (RI) 1(Sub-ingredient; SI) CAS # LINCS % SI in RI Formula Source Function

Water Water 7732-18-5 231-791-2 100.00 92.850 Natural Solvent

Propylene Glycol Propylene Glycol 57-55-6 200- 338-0 100.00 5.000 Synthetic Solvent Xylitol NF FCC Xylitol 87-99-0 201- 788-0 100.00 0.750 Synthetic Sweetener VanzanNF Xanthan-Gum 11138-66-2 234-394-2 100.00 0.550 Natural Thickener

Sodium Benzoate NF Sodium Benzoate 532-32-1 208-534-8 100.00 0.350 Synthetic Preservative Peppermint Oil Mentha Piperita 8006-90-* NA 100.00 0.200 Natural Flavor (Redistilled) (Peppermint) Oil

Citric acid Citric acid 77-92-9 0.150 Synthetic pH adjuster

Water 7732-18-5 231-791-2 15.00 Natural Solvent

Titanium Dioxide Titanium Dioxide 13463-67-7 236-675-5 100.00 0.100 Mineral Colorant ProtachemNA-2-P Disodium EDTA 139-33-3 205-358-3 100.00 0.050 Synthetic stabilizer

Total 100.000 Activator composition embodiment 4 can be prepared in a manner similar to the preparation of activator composition embodiment 1 above, yet with citric acid used in place of phosphoric acid.

Dispensers for Use with the Whitening System

Fig. 1 shows a first embodiment of a dispenser 100 for concurrently dispensing a whitening composition W and an activating composition A according to the invention. As shown in Fig. 1 whitening composition W or whitener W for convenience sake may be provided in a first volume such as a container in the form of a tube 114. Activating composition A, or activator A for convenience, may be provided in a second volume such as a container in the form of a tube 118 provided along with or directly adjacent to 114, depending on the intended use.

In order to discharge whitener W and activator A at the same time there may be provided an outlet 144 and a further outlet 148 for tubes 114 and 118, respectively. To ensure that whitening W and activator A are kept separate until provided on the user's teeth at the time the user's teeth are to be

whitened, there may be provided one or more valves, such as a first valve 154, which may be a one-way release valve, as well as a second valve 148, which may likewise be a one-way release valve. Release valves 154, 158 will be opened when the user presses against a plunger 130 in the direction of arrow 132 so as to evenly advance respective pistons 134 and 138 for

concurrently pushing whitener W and activator A out through associated outlet 144 and valve 154, and outlet 148 and its associated one-way valve 158, respectively, into a mixing region 166, as will be readily appreciated by a person having ordinary skill in the art.

A cap 174 may be provided to cover mixing region 166, when not in use, to prevent discharge of whitener W and activator A when not in use, as will be readily understood.

It will likewise be readily appreciated that mixing region 166 will be sized and configured to ensure mixing of whitening W and activator A at the time of dispensing of the whitener W and activator A onto the user's teeth.

The respective one-way release valves 144 and 148 prevent the whitener and activator from contact to avoid undesired activation of the whitening compound in whitener W; i.e., activating of whitener W by activator A at a time other than the time at which the whitening compound is to be activated on the user's teeth.

Fig. 2 shows a further embodiment of a dispenser 200 which likewise contains separate volumes defined by containers, such as the illustrated tubes 214 and 218 for containing, respectively, whitener W and activator A. Dispenser 200 likewise dispenses whitener W and activator A evenly and

concurrently, and differs from dispenser 100 of the embodiment of Fig. 1, for example, by the housing of dispenser 200 being similar to the housing of a tube, which may be a flexible tube, such as a toothpaste tube which is rolled up or flattened by the user, in use, such as by the user grasping free end 202 and moving free end 202 in a counterclockwise fashion as shown in the direction of arrow 206, in order to reduce the volume of chambers 214 and 218 at the same time and likewise to push out whitener W and activator A at the same time for forcing out whitener W and activator A through outlets 244 and 248, and valves 254 and 258, respectively, as will be readily understood.

Fig. 3 is a side view of the dispenser 200 of Fig. 2.

Fig. 4 illustrates a further embodiment of a dispenser 300 for use with tooth whitening system according to the invention.

Dispenser 300 includes a first container or dispenser 304, which may be in the form of a bottle or tube, as well as a second dispenser 308, which likewise may be in the form of a bottle or tube.

Dispenser 304 may include a brush 320 including a head 324 and bristles 328 for use by the user to withdraw an amount of whitener W from dispenser 304 and then apply whitener W on the user's teeth by use of bristles 324, as will be appreciated. In a like manner, brush 330 may be used to remove activator A from dispenser 308 by the user when applying activator A to the user's teeth by use of bristles 338.

In use, whitener W may be applied to the user's

teeth before or after application of activator A, depending on the chemical and physical characteristics of the whiteners and activators according to the invention.

In use, dispenser 300 may include the whitener in the form of a mouth rinse provided in one of dispensers 304 and 308, so that no brushing on is optional or unnecessary.

Various embodiments of whitening composition and activating composition according to the invention are set forth above.

While this invention has been described as having a

preferred design, it is understood that it is capable of further modifications, and uses and/or adaptations of the invention and following in general the principle of the invention and

including such departures from the present disclosure as come within the known or customary practice in the art to which the invention pertains, and as may be applied to the central features hereinbefore set forth, and fall within the scope of the invention.