WO2002085319A1

WO2002085319A1 - Fluoride compatible calcium carbonate

Info

Publication number: WO2002085319A1
Application number: PCT/US2001/013056
Authority: WO
Inventors: Patrick Clinton Wernett; Ali Reza Bashey
Original assignee: Specialty Minerals (Michigan) Inc.
Priority date: 2001-04-24
Filing date: 2001-04-24
Publication date: 2002-10-31
Also published as: NO20034712D0; BR0116983A; CN1505501A; JP2004527539A; CA2443747A1; KR20030090781A; EP1383476A1; TW200514574A; NO20034712L; SK13002003A3; PL363310A1

Abstract

The invention relates to a composition having finely divided calcium carbonate particles treated with fatty acids or polysaccharides. The invention further relates to a method for the preparation of the composition and its use in applications where fluoride compatibility is desired. The method entails providing finely divided calcium carbonate particles, treating the particles with at least one of fatty acids or polysaccharides including gums, starches and/or mucilages, and adding the treated particles to a fluoride containing toothpaste formulation.

Description

FLUORIDE COMPATIBLE CALCIUM CARBONATE

FIELD OF THE INVENTION

This invention relates to ingestable calcium carbonate compositions, a method for

its preparation, and the use of such in food products, supplements, mouth washes,

dentifrices, gels, chewable tablets and the like.

More particularly, this invention relates to treated calcium carbonate materials

that resolves the matter of taste and interaction with other components. One particular

problem addressed is that of chalky taste in food products and dietary supplements.

Another problem is food system compatibility and another is the problem of fluoride

stability in dental hygiene compositions.

BACKGROUND OF THE INVENTION

Calcium carbonate is used in food products and dietary supplements as well as

personal care products, which are used in the mouth. Such use can be in toothpaste and

powders, dietary or nutritional supplements, antacids, food products, such as breakfast

and snack foods, and the like. The benefits of such use can involve the uptake of calcium

into the body system for use elsewhere and for the physical properties of the calcium

carbonate in the oral cavity, such as in dental abrasives and carriers. When calcium carbonate is present in the oral cavity as a component of such

materials, the user can experience the unfavorable taste property of chalkiness. Such taste

experience may be affected by the physical character of the calcium carbonate material,

such as size and surface property. Another factor may be the chemical property such as

ionization and the like.

Calcium carbonate as a cleaning abrasive is a commonly used component in

toothpaste and tooth powders. Another component in toothpaste and tooth powders can

be fluoride to enhance enamel protection. Calcium carbonate can react with fluoride to

form calcium fluoride (CaF₂). When this reaction occurs, fluoride is unavailable to

interact with teeth to provide protection. This interaction may occur during the use of the

dental hygiene process or during storage over time. In either event, such reaction

decreases the effectiveness of the fluoride treatment and is not desirable.

European Patent Application No. 0 219 483 discloses a treated calcium carbonate

abrasive comprising pulverized calcium carbonate in a liquid dispersion with an alkali

metal pyrophosphate to produce a pyrophosphate derivative selected from the group

consisting of calcium pyrophosphate, calcium alkali metal pyrophosphate, and mixtures

thereof to chemisorb on the surface of the calcium carbonate particles.

U.S. Pat. No. 4,357,318 discloses a dentifrice comprising a water soluble

monofluorophosphate salt as a source of soluble fluoride in a therapeutically effective anti-caries concentration, an effective abrasive amount of calcium carbonate and a dibasic

alkali metal phosphate, said dentifrice being devoid of benzyl alcohol.

U.S. Pat. No. 3, 930, 305 discloses a dental cream containing an abrasive system

comprising sodium bicarbonate in a vehicle containing water and sufficient viscous water

miscible polyol humectant or mixtures thereof and a sufficient amount of gelling or

thickening agent to impart to the dental cream the pasty consistency, body and the non

tacky nature which is characteristic of conventional dental creams or toothpastes, and a

water-insoluble dental abrasive material compatible with said bicarbonate in the dental

cream, said sodium bicarbonate being primarily in the undissolved solid state, said dental

cream having a granular textured appearance comprising dispersed non-crystalline

appearing granulate of macroscopic crystalline bicarbonate granules in an otherwise

smooth continuous matrix.

U.S. Pat. No. 5,476,647 discloses a substantially phosphate-free two component

system for increased deposition of fluoride onto and into dental tissue, comprising a first

component of a soluble calcium source, a soluble calcium complexing agent and a buffer

and a second component containing a fluoride compound and a buffer. When the two

components are combined, there results a precipitation of calcium fluoride gradually and

continuously over the course of about 10 seconds to about 4 minutes.

U.S. Pat. No. 4,420,312 discloses a method for the production of an abrasive

composition comprising a precipitated amorphous silicon dioxide. The abrasive composition, when incorporated into toothpaste compositions containing a fluoride

therapeutic agent, provides a toothpaste composition which exhibits minimal loss of

soluble fluoride upon storage at normal temperatures.

U.S. Pat. No. 5,939,051 discloses a dentifrice composition, comprising an orally

acceptable dentifrice vehicle and a silica hydrogel.

U.S. Pat. No. 5,891,448 discloses a two-component system for delayed sustained

precipitation of calcium fluoride onto and into dental tissue comprising a first component

containing a soluble calcium source, with no more than approximately ten percent of the

calcium in complexed form; a second component containing a soluble fluoride

compound; and a calcium fluoride inhibitor present in either or both of components. The

second component is isolated from the reaction with the first component during storage

and prior to use. When the two components are combined, the inhibitor produces a delay

of at least about five seconds before significant formation of calcium fluoride occurs.

The level of phosphate in the system is less than the concentration needed for significant

precipitation of hydroxyapatite.

U.S. Pat. No. 5,723,107 discloses a method for fluoridating teeth utilizing a semi-

solid, extrudable, two component dentrifice system. The steps include preparing as a first

component a semi-solid, extrudable dentifrice composition containing a fluoride ion

releasable hydrolyzable complex fluoride compound in an aqueous acidic vehicle in

which the fluoride compound is stable, the vehicle being free of abrasive and surfactant and containing xanthan gum as the major thickening agent and glycerin, sorbitol or

mixtures thereof as the humectant, and as a second component, a semi-solid extrudable

aqueous dentifrice composition containing a calcium ion releasable compound and an

abrasive in an aqueous vehicle contains xanthan gum as the major thickening agent and

glycerin, sorbitol or mixtures thereof as the humectant. The first and second dentifrice

compounds are kept separate from the other until application to teeth requiring

fluoridation. Then the first and second components are mixed together to deposit calcium

fluoride therefrom on contact with a tooth surface.

U.S. Pat. No. 5,145,668 discloses a method for fluoridating teeth with a reactive,

multi-component composition. There are mixed a first component comprising calcium

chloride together with a second component comprising sodium fluorosilicate, an acetate

salt, and a sufficient quantity of soluble, non-toxic phosphorous salt to maintain the

phosphorous concentration at a desired level. The sodium fluorosilicate of the reactive

multi-component composition is hydrolyzed, and calcium fluoride is precipitated from

the reactive multi-component composition. The reactive multi-component composition is

applied to tooth surfaces for a period of time ranging from about 10 seconds to about 4

minutes.

There remains the need to provide calcium carbonate particles in dental hygiene

material, food products, antacids, dietary and nutritional supplements and the like in a

form which has pleasant texture and palatable taste and without interfering with other

beneficial components. An object of the present invention is to produce a calcium carbonate particle that

is stable when used in an environment where fluoride ions are present (being "stable"

means the calcium carbonate does not react significantly with the fluoride ions or other

components).

Another object of the present invention is to provide a process for producing

calcium carbonate particles that are stable in an environment where fluoride ions are

present. A further object of the present invention is to provide calcium carbonate

particles that are stable when used in formulations where fluoride ions are present. These

and other objects of the present invention are more fully disclosed in the detailed

description of the embodiments of the invention, which hereinafter follows.

SUMMARY OF THE INVENTION

The present invention solves the problem of fluoride stability in toothpaste when

calcium carbonate is used as an abrasive. In the present invention, calcium carbonate is

treated with polymers and/or fatty acids making it fluoride compatible in toothpaste

formulations.

The present invention is a fluoride compatible surface treated calcium carbonate

dental abrasive that is effective when used in an environment where fluoride

compatibility is required. The present invention also solves the problem of chalkiness taste when ingesting

material containing calcium carbonate particles by providing a calcium carbonate particle

treated with polymers and/or fatty acids.

The present invention also provides enhanced shelf life to material using the

treated calcium carbonate particles in that such particles have reduced reactivity with

other components.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a surface treated calcium carbonate particle in

which the treatment is effective when the calcium carbonate particle is used in an

environment where oral hygiene or ingestion is required. In particular, the surface treated

calcium carbonate particular manifests beneficial taste characteristics or interacts

beneficially with fluoride delivery systems by having reduced characteristics to impact

fluoride stability in such systems.

One embodiment of the present invention is an ingestible material comprising

calcium carbonate particles, in which the calcium carbonate particles have been

effectively treated with one or more agents selected from the group consisting of fatty

acids and polysaccharides to reduce the sensation of chalkiness in said ingested material

due to the presence of the calcium carbonate particles. In such use the ingestible material can be any material for consumption, such as

food products, dietary and nutritional supplements, pharmaceuticals and the like. The

presence of a calcium carbonate particle in such material can be for any of a variety of

reasons. Such reasons include, without limitations, use of calcium carbonate to provide

elemental, texture, filler or other purposes. Examples include, without limitation,

processed foods, dietary and nutritional supplements, dental hygiene compositions,

denture adhesives and the like.

Suitable calcium carbonate particles that may be surface treated by the process of

the present invention include calcium carbonate particles having the morphological forms

of aragonite, calcite, vaterite, amorphous and mixtures thereof. The calcium carbonate

particles may also be synthetically produced precipitated calcium carbonate (PCC) or

ground natural calcium carbonate. A preferred calcium carbonate particle has a median

particle size of from about 0.5 to about 30 micrometers, preferably from about 1 to about

15 micrometers. The specific surface area of calcium carbonate particle of the present

invention is from about 0.5 meters square per gram to about 50 meters square per gram.

A preferred specific surface area is from about 1 to about 10 meters square per gram.

The specific surface area of the calcium carbonate is defined herein as the area per unit

mass based on the sorption of nitrogen using the BET method.

Suitable surface treating agents include fatty acids and polysaccharides. The

fatty acids that are useful in the present invention have the general chemical formula of CH₃(CH₂)_xCO₂H, in which X ranges from about 2 to about 20, more preferably from about 8 to about 20. The fatty acid can be saturated or unsaturated. Substitution is

permissible as long as the substitution does not substantially impact the beneficial

properties of the present invention. Preferred fatty acids have the common names of

lauric, palmitic, stearic, oleic, linoleic, and behenic. The treating level for fatty acids

can range from about 0.01 percent to about 20 percent, preferably from about 0.05

percent to about 4 percent, based on the dry weight of calcium carbonate. The treating

level can be affected by the surface area of the calcium carbonate in that as the particle size decreases, the treating level increases.

Preferred polysaccharides used in the present invention have nine or more units

of monosaccharides (C₆H₁₂O₆) linked by glycosidic bonds and include, but are not limited to, gums, starches and mucilages. Other preferred polysaccharides that are useful in the present invention may be selected from the group consisting of alginates,

xanthans. guar, carrageenan, gellan, and the like. The treating level for polysaccharides

can range from about 0.05 percent to about 20 percent, preferably from about 0.05

level is affected by the surface area of the calcium carbonate in that as the particle size

decreases, the treating level increases generally.

One preferred polysaccharide form is starch. Starches that are useful in the

present invention may be selected from the group consisting of potato, corn, tapioca,

carboxymethylcellulose, and the like. The treating level for starches can range from about 0.05 percent to about 20 percent, preferably from about 0.05 percent to about 4

percent, based on the dry weight of calcium carbonate. The treating level is affected by

the surface area of the calcium carbonate. What this means, is that as the calcium

carbonate particle size increases the treating level decreases. As the particle size

decreases, the treating level increases.

Another preferred form of polysaccharides is mucilages. Mucilages that are

useful in the present invention may be selected from the group consisting of agar,

tragacanth mucilage, yellow or white mustard mucilages and the like. The treating level

for mucilages can range from about 0.05 percent to about 20 percent, preferably from

about 0.05 percent to about 4 percent, based on the dry weight of calcium carbonate.

The treating level is affected by the surface area of the calcium carbonate. What this

means, is that as the calcium carbonate particle size increases the treating level

decreases. As the particle size decreases, the treating level increases.

In order to treat the calcium carbonate of the present invention with a fatty acid

such as, for example, stearic acid, the fatty acids can be applied to calcium carbonate by

dry coating. Dry coating is achieved by adding stearic acid to a dry calcium carbonate

and mixing at a temperature from about 40 to about 200 degrees Celsius. The

temperature range should be sufficient enough to melt the fatty acid. The resultant

calcium carbonate is treated with the fatty acid. The calcium carbonate of the present invention so treated is particularly suitable for use in mouthwashes, dentifrices, gels,

and chewable tablets where fluoride compatibility is desired.

An alternative method to dry coating is to wet coat the calcium carbonate. Wet

coating is achieved by adding a solution or emulsion of fatty acids or polysaccharides

including gums, starches and mucilages to a calcium carbonate slurry. The calcium

carbonate slurry is prepared by synthesizing calcium carbonate in an aqueous

environment or adding water to a dried calcium carbonate powder.

Another alternative method for treating the calcium carbonate is by adding dry

calcium carbonate to a solution or emulsion of fatty acids or polysaccharides including

gums, starches and mucilages. Still another alternative method for treating the calcium

carbonate is by adding dry fatty acids or polysaccharides including gums, starches and

mucilages to a calcium carbonate slurry.

The calcium carbonate abrasive treated in accordance with this invention

improves fluoride compatibility when incoφorated into oral hygiene products such as,

toothpaste, toothpowder, chewable gum, tablets, and other dentifrices.

The treated calcium carbonate abrasive of this invention can be used as the sole

abrasive in the oral hygiene product or can be used in conjunction with other dental

abrasives. Other suitable abrasives include water-insoluble sodium or potassium metaphosphates, hydrated or anhydrous dicalcium phosphate, sodium bicarbonate,

calcium pyrophosphate, various forms of silica, zirconium, silicate and the like.

The total amount of abrasives employed in oral hygiene products can range from

less than 5 percent to more than 95 percent by weight of the dentifrice. Generally,

toothpaste contains from 20 percent to 60 percent by weight of abrasive. Abrasive

average particle size preferably ranges from about 2 microns to 20 microns.

In addition to the abrasive, toothpaste and tooth powder compositions

conventionally contain one of or a combination of a fluoride compound, sudsing agents,

binders, humectants, flavoring agents, sweetening agents and water.

Suitable fluoride compounds can be any of the compounds previously mentioned

conventionally employed to provide available fluoride ion in the oral cavity. Sodium

monofluorophosphate, sodium fluoride and the like, have been employed with good

results in toothpaste to promote dental hygiene. Good results can be achieved

employing an amount of fluoride compound to provide available fluoride ion in the

range of 300 to 2000 ppm in the toothpaste, preferably 1000 ppm.

Suitable sudsing agents are generally anionic organic synthetic detergents active

throughout a wide pH range. Representative of such sudsing agents used in the range

of about 0.5 percent to 5 percent by weight of the composition are water-soluble salts of

C₁₀-C_lg alkyl sulfates, such as sodium lauryl sulfate; of sulfonated monoglycerides of fatty acids, such as sodium monoglyceride sulfonates; of fatty acid amides of taurine,

such as sodium N-methyl-N-palmitoyltauride; and of fatty acid esters of isethionic acid,

and aliphatic acylamides, such as sodium N-lauroyl sarcosinate.

Suitable binders or thickening agents to provide the desired consistency are, for

example, hydroxyethylcellulose, sodium carboxymethylcellulose, natural gums, such as

gum karaya, gum arabic, gum tragacanth, colloidal silicates and finely divided silica.

Generally, from 0.5 percent to 5 percent by weight of the composition can be used.

Various humectants can be used, such as glycerine, sorbitol and other

polyhydric alcohols.

Suitable flavoring agents include oil of wintergreen, oil of spearmint, oil of peppermint, oil of clove, oil of sassafras and the like. Saccharin, aspartame, dextrose,

levulose can be used as sweetening agents.

The following examples are being presented to further illustrate and support the

novelty of the present invention. They are presented for illustrative purposes only and

should in no way be used to limit the scope of the coverage, which is more specifically

defined by the claims that are attached hereto. TEST METHODS AND PROCEDURES

XPS Surface Analysis

XPS (X-ray Photoelectron Spectroscopy) also referred to as ESCA (Electron

Spectroscopy for Chemical Analysis) is a surface sensitive technique with an analysis

depth of 5 - 50 Angstroms (A) (0.0005 - 0.005 microns). Samples are bombarded with

X-rays causing electrons to be emitted. The electrons which evolve without energy loss

originate from the top few monolayers. The spectrometer separates these electrons

according to their kinetic energy. The energies of the photoelectrons depend not only

on the chemical element from which the electrons originate but also upon the chemical

environments of that element. The results are expressed in atom percent. For

example, if the analysis results read "1.5 percent F (NaF)", then that is interpreted as

1.5 percent of the atoms on the surface are fluorine ions that are attached to a sodium

atom.

Hefferren Method for Assessment of Dentifrice Abrasivity

The Hefferren method measures the Radioactive Dentin Abrasivity (RDA) number, also

called the Abrasivity Index (Al). This method utilizes the roots (dentin) of extracted

human teeth, which are irradiated by a neutron flux. The teeth are mounted and brushed

with a slurry of the toothpaste in question at a certain pressure and number of strokes.

After brushing an aliquot of the slurry is dried and beta radiation is measured. The more

abrasive the toothpaste under test, the more radioactivity associated with the slurry. The

results are compared to a reference abrasive provided by the American Dental Association (ADA). The results are expressed as Abrasivity Index (Al). The Al values

are interpreted for toothpaste as follows:

Less than 99 low abrasion 100 - 199 medium abrasion

200 - 250 high abrasion greater than 250 unacceptable

Example 1 - Uncoated Calcium Carbonate vs. Coated Calcium Carbonate

Samples of uncoated and treated ground calcium carbonate products having a

surface area of 1.1 meters square per gram and a median particle size of 9.1 microns were

mixed in a beaker at 18 percent solids while a sodium monofluorophosphate (MFP)

fluoride solution was added to a level of 0.88 percent. The slurries were allowed to mix

for ten (10) minutes before filtration. The filter cakes were dried in an oven of 110

degrees Celsius overnight and surface analyzed by XPS (x-ray Photoelectron

Spectroscopy).

Surface fluoride analysis results are presented in Table 1. In Table 1, F (CaFJ

denotes fluoride that has reacted with CaCO₃ and is unstable. The F (MFP) denotes

fluoride that has not reacted with calcium carbonate and is therefore stable. This form of

fluoride would be available to react with and protect teeth. TABLE 1

Surface Fluorine Content of Dried Filter Cakes (atom percent)

untreated 0.1% Na St 0.5%Na St 0.1% Guar 0.5% Guar F (CaF₂) 1.5 0.4 . — 1.1 0.8 F (MFP) — — — 0.9 1.5

Note: — indicates an undetectable amount. A typical detection limit for fluoride is

approximately 0.05 atom present.

XPS analyses demonstrate that coating GCC with sodium stearate (NaSt) results

in a stable system.

Coating with guar gum creates a stable system. When the level of guar gum is

increased from 0.1 percent to 0.5 percent, based on the dry weight of the guar and the

dry weight of the calcium carbonate, the stability of the system increases.

Example 2 - Comparative Stability of Calcium Carbonate Using Other Treatments

The same laboratory experiments were conducted with ground calcium

carbonate (GCC) as in Example 1. Each treatment was applied at a level of 0.1 percent

and 0.5 percent based on dry weight of the treatment and dry weight of calcium

carbonate. The results of the surface fluoride analysis of the dried filter cakes are

presented in Table 2: TABLE 2

Surface Fluoride Content

F (CaF₂) F (MFP)

Untreated GCC 1.5

CMC 0.1 % 0.7

CMC 0.5% 0.9

Carrageenan 0.1 % 1.0

Carrageenan 0.5% 1.2

Sodium Alginate 0.1 % 1.6

Sodium Alginate 0.5% 0.3

Xanthan 0.1 % 0.6

Xanthan 0.5% failed

Gellan 0.1 % 1.2

Gellan 0.5% 1.1

Linoleic 0.1 % 0.4

Linoleic 0.5% 0.4

Hydroxystearic 0.1 % 0.5

Hydroxystearic 0.5% 0.3

Table 2 demonstrates that the calcium carbonate tr

linoleic and hydroxystearic, and sodium alginate, at the higher treatment levels, increase

stability. The polysaccharides, xanthan, and carboxymethylcellulose also increase

stability but not as well as the fatty acids and the sodium alginate.

Example 3 - Effects of Treatments on Abrasivity in a Toothpaste Formulation

Four experimental GCC products treated with sodium stearate and guar gum at

0.1 percent and 0.5 percent were incorporated into a toothpaste formulation with the

following composition: %W/W

Calcium Carbonate 18.00

Sident 22S 11.20

Titanium Dioxide 0.50

Sodium Saccharin 0.20

Sodium Benzoate 2.20

Glycerin 12.00

Sorbitol 15.00

Methyl Paraben 0.03

Xanthan Gum 0.40

Sodium Lauryl Sulfate 1.30

PEG-8 7.00

Oil of peppermint 0.80

Purified water 31.37

Five toothpaste formulations containing treated GCC abrasives were tested for

abrasivity.

Sample Description Abrasivity Index

• uncoated GCC 136

• GCC +0.5percent stearic acid 128

GCC +0.1 percent stearic acid 120

• GCC +0.1 percent guar gum 163

GCC + 0.5percent guar gum 165 An abrasion index for toothpaste of:

99 and less - low abrasion

100-199 medium

200-250 high

> 250 unacceptable high abrasion

Stearic acid and guar gum treated GCC are in the medium abrasive range. The

treatment level on the calcium carbonate does not adversely affect abrasion.

Claims

What is claimed is:

1. Composition comprising an orally acceptable hygiene media, calcium carbonate

particles suitable for use as a dental abrasive, a fluoride compound suitable to

provide beneficial fluoride treatment to teeth, wherein said calcium carbonate

particles have been effectively treated with one or more agents selected from the

group consisting of fatty acids and polysaccharides to inhibit reaction of fluoride

ions of said fluoride compound and said calcium carbonate particles.

2. Composition of claim 1 wherein said media is toothpaste or tooth powder.

3. Composition of claim 2 wherein said calcium carbonate particles have an

average particle size of .5 to 30 micrometers.

4. Composition of claim 2 wherein said calcium carbonate particles have a specific

surface area of .5 to 50 meters squared per gram.

5. Composition of claim 1 wherein said calcium carbonate particles are precipitated

calcium carbonate

6. Composition of claim 1 wherein said fluoride compound is a sodium

monofluorophosphate .

7. Composition of claim 1 wherein said agent is one or more of a fatty acid

selected from the group consisting of lauric acid, palmitic acid, stearic acid,

oleic acid, linoleic acid, and behenic acid.

8. Composition of claim 1 wherein said agent is one or more of a polysaccharide

selected from the group consisting of alginates, xanthans, guar, carrageenan,

and gellan.

9. Composition of claim 1 wherein said treatment is effective to reduce the uptake

of fluoride ions by said calcium carbonate material by 50 percent.

10. Composition of claim 1 wherein said treatment comprise coating at least a

portion of said calcium carbonate material

11. A composition comprising an orally acceptable hygiene media, calcium

carbonate particles suitable for use as a dental abrasive, a fluoride compound

suitable to provide fluoride ions for beneficial treatment to teeth, and one or

more agent(s) selected from the group consisting of fatty acids and

polysaccharides, wherein said agent(s), said calcium carbonate particles and said

fluoride ions effectively interact to create a system to inhibit reaction of said

fluoride ions and said calcium carbonate particles.

12. A method of treating teeth with fluorine in an oral environment containing

calcium carbonate material comprising first treating the calcium carbonate

material with an agent to inhibit the uptake of fluorine by said calcium carbonate

material.

13. A composition comprising an orally acceptable ingestable media and calcium

carbonate particles suitable for use in said media, said calcium carbonate

particles effectively coated with a polysaccharide or a fatty acid wherein said

coating is effective to increase the palatability of said calcium carbonate to the

ingester of said media.

14. A toothpaste composition comprising calcium carbonate particles suitable for use

as a dental abrasive, a fluoride compound suitable to provide beneficial fluoride

treatment to teeth, wherein said calcium carbonate particles have been effectively

treated with one or more agents selected from the group consisting of fatty acids

and polysaccharides to inhibit reaction of fluoride ions of said fluoride compound

and said calcium carbonate particles.