Abstract:
Cosmetic pencils having cores consisting of water-set mixtures of plaster of paris, mica or other laminar material and pigment or color are disclosed. The mixtures are between 30 wgt % and 75 wgt % plaster of paris. The pencils may be made either by pouring water-based slurries of the mixtures into hollow pencil cases, or by introducing pre-formed cores into two-part cases which are subsequently secured together. The pencils can be easily sharpened and may contain a wide range of additives such as preservatives and bacterioistats.

Description:
BACKGROUND TO THE INVENTION 
     1. Field of the Invention 
     This invention relates to pigmented compositions, for example compositions suitable for forming the core of a cosmetic pencil. 
     2. Description of Prior Art 
     A known cosmetic powder pencil core consists of pigment or colouring material, an extender such as a clay for modifying the intensity of the pigment or colouring material, a modifier such as a clay or zinc stearate for modification of the structure or other properties of the core, and a binder comprising a gum or gum-like material. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a composition comprising a pigment or colouring material, plaster of paris (calcium sulphate hemihydrate) and mica or other material having a laminar structure, the composition containing 30 to 75 wgt %, preferably 35 to 70 wgt % and, more preferably, at least 40 wgt % plaster of paris. Most preferably, the composition contains about 45 wgt % plaster of paris. 
     The amount of laminar material may be as low as 10 wgt % of the composition but is preferably at least 20 wgt % of the composition. The preferred upper limit to the amount of laminar material is 50 wgt % of the composition. The particle size of the laminar material is preferably in the range of from 5 μm to 100 μm and more preferably in the range of from 5 μm to 40 μm. 
     The composition may also contain additives or modification agents, for example emollients, fillers, extenders, preservatives, bacteriostats and accelerators or retarders for the setting of the plaster of paris component. Preferably, the total amount of additives or modification agents is no more than 5 wgt % of the composition. 
     Compositions according to the invention may include some calcium sulphate dihydrate or barium sulphate in the dry mix of ingredients, the preferred amount being up to 20 wgt % of the composition. 
     The pigment or colouring material advantageously comprises an opacifying agent such as titanium dioxide or bismuth oxychloride. The mica or laminar material may conveniently be coated with opacifying agent and/or be pre-mixed with the pigment or colouring material. Alternatively, one or all of the opacifying agent, the pigment or colouring material and the laminar material can be added as separate ingredients to the plaster of paris. The preferred level of pigment or colouring material in the composition is from 5 to 30 wgt % of the composition. 
     To form the dry composition into a pencil core, a portion of the dry composition is mixed with water, formed into a desired core shape, caused or allowed to set and then dried. Accelerating or retarding agents for plaster of paris may be added to the dry composition or the mixture. Typically, the dry composition is mixed with approximately twice its weight of water. 
     Instead of introducing the additives or modification agents mentioned above into the dry mix of ingredients, these additives or agents may be first disolved in water to form an aqueous solution in which the other dry ingredients are subsequently disolved. 
     In one procedure for making a cosmetic pencil, after mixing and before setting, the wet material in the form of a slurry is poured or pumped directly into preformed wooden pencil cases, comprising wooden cylinders each with a longitudinal cylindrical bore. The cases are conveniently held in an upright position with an open end of the bore uppermost. When no accelerator or retardant is used setting may be achieved by allowing the filled case to stand for approximately 20 minutes at room temperature. This period may be lengthened to about 2 hours or shortened to about 3 minutes by use of a suitable retardant or accelerator. The set composition may then be dried at an elevated temperature of, say, 35° to 60° C. for a period of, for example, 24, 48 or 72 hours. Otherwise, drying may be achieved by allowing the filled cases to stand at room temperature for an appropriate time period, or by freeze or vacuum drying. During the drying process water from the mixture evaporates through the tip of the core exposed by the case and also through the wooden case material which is sufficiently porous to allow such evaporation. In the setting process, the calcium sulphate hemihydrate is converted to calcium sulphate dihydrate and the set composition therefore contains a stoichiometric amount of water. Apart from this water of crystallisation, the set compositions will contain little or no water. 
     In another procedure, the wet composition is moulded and set into rod-shaped pencil cores which are subsequently introduced into a two-part wooden block having a plurality of recesses which are opened longitudinally for introduction of the cores when the block parts are separated. After fitting of the cores to one block part, the two parts are united, the parts secured together and the block cut and shaped into a plurality of pencils. The cores are then allowed to dry. 
     It has been found that the cores of cosmetic pencils made in accordance with the present invention can have excellent adhesion to their cases. 
     After drying, the pencils formed by either procedure are sharpened at one end to form and expose a conical tip of the core. 
     The composition of the invention has the advantages of inexpensiveness and simplicity compared with the known core composition. The finished pencil has an improved appearance compared with known cosmetic pencils and can contain a much wider range of additive materials, for example emollients, preservatives and bacteriostats. The pay-off properties of the pencils are also good. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The sole FIGURE of the drawing of this specification shows a cosmetic powder pencil made in accordance with one aspect of the present invention. 
    
    
     DETAILED DESCRIPTION 
     The pencil comprises a cylindrical wooden pencil case 1 having a longitudinal cylindrical bore 2 into which has been poured or pumped a mixture of a composition according to the invention and water, the mixture having subsequently set to form a core 3 of the pencil. The core is about 12 cm long and about 6.9 mm in diameter. One end of the core 3 has been sharpened into a conical tip 4. 
     In a modified procedure, the tip 4 can be formed integrally with the remainder of the core 3 by moulding. 
     In a further modification, two pencils are formed simultaneously in a case of twice the length shown in the drawings which is subsequently cut into two equal-length parts. 
     Examples will now be given of compositions according to the invention: 
     EXAMPLE 1 
     Composition for Dark Blue Cosmetic Pencil 
     
         ______________________________________                    wgt %______________________________________Plaster of paris                   64.6Titanium dioxide   as TiO.sub.2 coated                              6.5              micaMica                               18.5Ferric ferrocyanide                10.0Methylparahydroxybenzoate          0.2Propylparahydroxybenzoate                   Preservatives                              0.1Sodium dehydroacetate              0.1                              100.0______________________________________ 
    
     EXAMPLE 2 
     Composition for Light Blue Cosmetic Pencil 
     
         ______________________________________                    wgt %______________________________________Plaster of paris                   49.6Titanium dioxide   as TiO.sub.2 coated                              13.6              micaMica                               26.4Ferric ferrocyanide                10.0Methylparahydroxybenzoate          0.2Propylparahydroxybenzoate                   Preservatives                              0.1Sodium dehydroacetate              0.1                              100.0______________________________________ 
    
     EXAMPLE 3 
     Composition for Green Cosmetic Pencil 
     
         ______________________________________                 wgt                 %______________________________________Plaster of paris                49.6Titanium dioxide as TiO.sub.2 coated                           23.0            mica                    Pre-Mica                            23.0     mixedIron oxide                      3.0Ferric ferrocyanide             1.0Methylparahydroxybenzoate                 Preserva- 0.2Propylparahydroxybenzoate                 tives     0.1Sodium Dehydroacetate           0.1                           100.0______________________________________ 
    
     In each Example, the ingredients listed above were thoroughly mixed together and then mixed with approximately twice their weight of water. The wet mixture could then be used in the manufacture of cosmetic pencils in a manner described hereinbefore. 
     For use in Examples 4 to 42 which follow, the following aqueous bacteriocide and fungicide solution was prepared; 
     2 parts by volume of a 1% sodium dehydroacetate solution in deionised water 
     4 parts by volume of 1% Germall 115 solution in deionised water 
     29 parts by volume of deionised water 
     Dry mixtures as specified in Examples 4 to 35 were then made up and 200 g portions of the mixtures were mixed with the volumes of the bacteriocide and fungicide solution stated in the individual examples. The mixtures were stirred gently to avoid aeration, sieved and then injected by means of an injection gun into empty wooden pencil cases in the form of hollow cylinders of 6.90 mm internal diameter and mm in length. The total time from mixing to injection did not exceed 12 minutes. Within 12 minutes of injection the pencils cores had solidified. The pencils were then transferred to a drying oven for a period of between 48 and 72 hours. After drying, one end of each pencil was sharpened with a pencil-sharpener to produce a finished make-up pencil. 
     In the following examples the figures in parentheses after certain pigments or colouring materials indicate that those materials contain mica in the indicated amounts by weight. 
     EXAMPLE 4 
     Composition for Highlighter Pencil 
     
         ______________________________________                    wgt %______________________________________12.5    kg     Superfine casting plaster of paris                              50.012.0    kg     Soloron Silver (70%)                              48.00.5000  kg     Ariabel Umber        2.0Mica content of mixture    33.6Pigment content of mixture 16.4______________________________________ 
    
     200 g of the mixture was mixed with 275 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 5 
     Composition for Golden Bronze Pencil 
     
         ______________________________________                    wgt %______________________________________2.00 kg    Superfine casting plaster of paris                              50.02.00 kg    Cloisonne Golden Bronze (62 to 68%)                              50.0Mica content of mixture    31.0 to 34.0Pigment content of mixture 16.0 to 19.0______________________________________ 
    
     200 g of the mixture was mixed with 290 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 6 
     Composition for Green Pencil 
     
         ______________________________________                  wgt %______________________________________13.75kg     Superfine casting plaster of paris                            55.011.25kg     Cloisonne Super Green (44 to 48%)                            45.0Mica content of mixture  19.8 to 21.6Pigment content of mixture                    23.4 to 25.2______________________________________ 
    
     200 g of the mixture was mixed with 225 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 7 
     Composition for Silver Grey Pencil 
     
         ______________________________________                   wgt %______________________________________12.50  kg     Superfine casting plaster of paris                             50.010.00  kg     Soloron Silver (70%)                             40.02.50   kg     Black 300401        10.0Mica content of mixture   28.0Pigment content of mixture                     22.0______________________________________ 
    
     200 g of the mixture was mixed with 350 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 8 
     Composition for Blue Pencil 
     
         ______________________________________                  wgt %______________________________________11.875 kg     Superfine casting plaster of paris                            47.5011.875 kg     Duochrome BR (55-62%)                            47.501.250 kg     300308 Ariabel Blue  5.00Mica content of mixture  26.12 to 29.44Pigment content of mixture                    23.06 to 26.38______________________________________ 
    
     200 g of the mixture was mixed with cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 9 
     Composition for Dusty Pink Pencil 
     
         ______________________________________                   wgt %______________________________________13.75  kg     Superfine casting plaster of paris                             55.0010.16  kg     Soloron Silver (70%)                             40.640.62   kg     Carmine 1275        2.480.38   kg     Black 300401        1.520.09   kg     Blue 300308         0.36Mica content of mixture   28.45Pigment content of mixture                     16.55______________________________________ 
    
     200 g of the mixture was mixed with 300 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 10 
     Composition for Green Pencil 
     
         ______________________________________                 wgt %______________________________________13.75kg     Superfine casting plaster of paris                           55.09.75 kg     Cloisonne Nu Antique Gold                           39.01.25 kg     Black iron oxide 300401                            5.00.25 kg     Ariabel Blue 300308  1.0Mica content of mixture 19.89 to 22.23Pigment content of mixture                   22.77 to 25.11______________________________________ 
    
     200 g of the mixture was mixed with 250 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 11 
     Composition for Mulberry Pencil 
     
         ______________________________________                   wgt %______________________________________13.25kg    Superfine casting plaster of paris                             53.005.00 kg    Soloron Silver (70%)   20.005.35 kg    Cloisonne Nu Antique Rouge Flambe                             21.400.60 kg    Black 300401            2.400.80 kg    Red 300318              3.20Mica content of mixture   24.49 to 25.77Pigment content of mixture                     21.23 to 22.51______________________________________ 
    
     200 g of the mixture was mixed with 280 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 12 
     Composition for Blue Pencil 
     
         ______________________________________                 wgt %______________________________________1.70 kg     Superfine casting plaster of paris                           42.502.08 kg     Duochrome BR (55 to 62%)                           52.000.22 kg     300308 Blue          5.50Mica content of mixture  28.6 to 32.24Pigment content of mixture                   25.26 to 28.9______________________________________ 
    
     200 g of the mixture was mixed with 270 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 13 
     Composition for Punk Pink Pencil 
     
         ______________________________________                 wgt %______________________________________2.00 k      Superfine casting plaster of paris                           50.02.0  kg     Duochrome RB (48 to 54%)                           50.0Mica content of mixture 24.0 to 27.0Pigment content of mixture                   23.0 to 26.0______________________________________ 
    
     200 g of the mixture was mixed with 250 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 14 
     Composition for Silver Grey Pencil 
     
         ______________________________________                   wgt %______________________________________1.80   kg     Superfine casting plaster of paris                             45.01.80   kg     Soloron Silver (70%)                             45.0.40    kg     Black 300401        10.0Mica content of mixture   31.5Pigment content of mixture                     23.5______________________________________ 
    
     200 g of the mixture was mixed with 350 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 15 
     Composition for Gold Pencil 
     
         ______________________________________                    wgt %______________________________________1.80 kg    Superfine casting plaster of paris                              45.02.20 kg    Cloisonne Golden Bronze (62 to 68%)                              55.0Mica content of mixture    34.1 to 37.4Pigment content of mixture 17.6 to 20.9______________________________________ 
    
     200 g of the mixture was mixed with 300 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 16 
     Composition for Antique Bronze Pencil 
     
         ______________________________________1.90 kg     Superfine casting plaster of paris                           47.501.80 kg     Cloisonne Nu Antique Gold                           45.50       (51 to 57%)0.24 kg     Black 300401         6.00.40  kg     Blue 300308          1.00Mica content of mixture 23.21 to 25.94Pigment content of mixture                   26.56 to 29.29______________________________________ 
    
     200 g of the mixture was mixed with 270 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 17 
     Composition for Highlighter Pencil 
     
         ______________________________________                   wgt %______________________________________1.80   kg     Superfine casting plaster of paris                             45.02.12   kg     Soloron Silver (70%)                             53.00.08   kg     Umber 300403         2.0Mica content of mixture   37.1Pigment content of mixture                     17.9______________________________________ 
    
     200 g of the mixture was mixed with 360 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 18 
     Composition for Blue Highlighter Pencil 
     
         ______________________________________                 Wgt %______________________________________1.80 kg     Superfine casting plaster of paris                           45.02.20 kg     Duochrome YB (48 to 54%)                           55.0Mica content of mixture 26.4 to 29.7Pigment content of mixture                   25.3 to 28.6______________________________________ 
    
     200 g of the mixture was mixed with 250 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 19 
     Composition for Apple Cordial Pencil 
     
         ______________________________________                 Wgt %______________________________________1.80 kg     Superfine casting plaster of paris                           45.02.20 kg     Duochrome GY (58 to 64%)                           55.0Mica content of mixture 31.9 to 35.2Pigment content of mixture                   19.8 to 23.1______________________________________ 
    
     200 g of the mixture was mixed with 250 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 20 
     Composition for Sapphire Pencil 
     
         ______________________________________                 Wgt %______________________________________1.80 kg     Superfine casting plaster of paris                           45.001.60 kg     Cloisonne Blue (48 to 54%)                           40.000.38 kg     RS 5 Ultra Blue      9.500.22 kg     Soloron Silver Sparkle (70%)                            5.50Mica content of mixture 23.05 to 25.45Pigment content of mixture                   29.55 to 31.95______________________________________ 
    
     200 g of the mixture was mixed with 250 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 21 
     Composition for Sky Blue Pencil 
     
         ______________________________________                   Wgt %______________________________________1.80   kg     Superfine casting plaster of paris                             45.001.152  kg     Soloron Silver (70%)                             28.800.86   kg     Timiron MP45 (80%)  21.500.18   kg     RS 5 Ultra Blue      4.500.008  kg     Ariabel Blue 300     0.20Mica content of mixture   38.65Pigment content of mixture                     16.35______________________________________ 
    
     EXAMPLE 22 
     Composition for Blue Mist Pencil 
     
         ______________________________________                 Wgt %______________________________________1.80 kg     Superfine casting plaster of paris                           45.02.20 kg     Duochrome GB (58 to 64%)                           55.0Mica content of mixture 31.9 to 35.2Pigment content of mixture                   19.8 to 23.1______________________________________ 
    
     200 g of the mixture was mixed with 230 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 23 
     Composition for Jade Pencil 
     
         ______________________________________                   Wgt %______________________________________1.80   kg     Superfine casting plaster of paris                             45.01.84   kg     Soloron Blue Green (45%)                             46.00.24   kg     Ariabel Green        6.00.12   kg     Soloron Silver (70%)                              3.0Mica content of mixture   22.8Pigment content of mixture                     32.2______________________________________ 
    
     200 g of the mixture was mixed with 300 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 24 
     Composition for Mocca Pencil 
     
         ______________________________________                   wgt %______________________________________1.80   kg     Superfine casting plaster of paris                             45.01.32   kg     Soloron Silver (70%)                             33.00.40   kg     Ariabel Yellow 300407                             10.00.32   kg     Ariabel Umber 300403                              8.00.16   kg     Ariabel Black 300401                              4.0Mica content of mixture   23.1Pigment content of mixture                     31.9______________________________________ 
    
     200 g of the mixture was mixed with 340 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 25 
     Composition for Khaki Pencil 
     
         ______________________________________                 wgt %______________________________________1.80 kg     Superfine casting plaster of paris                           45.01.80 kg     Cloisonne Nu Antique Gold                           45.0       (51 to 57%)0.20 kg     Black 300401        5.00.04 kg     Blue 300308         1.00.16 kg     Soloron Silver (70%)                           4.0Mica content of mixture 25.75 to 28.45Pigment content of mixture                   26.55 to 29.25______________________________________ 
    
     200 g of the mixture was mixed with 295 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 26 
     Composition for Baby Blue Pencil 
     
         ______________________________________                 wgt %______________________________________1.80 kg     Superfine casting plaster of paris                           45.01.08 kg     Cloisonne Blue (48-54)                           27.00.72 kg     Soloron Silver (70) 18.00.36 kg     4500 Chromalite Blue                            9.00.004kg     Blue 300308          1.0Mica content of mixture 30.06 to 32.31Pigment content of mixture                   22.69 to 24.94______________________________________ 
    
     200 g of the mixture was mixed with 300 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 27 
     Composition for Lilac Mist Pencil 
     
         ______________________________________                 wgt %______________________________________1.80 kg     Superfine casting plaster of paris                           45.01.64 kg     Soloron Silver (70%)                           41.00.40 kg     Duochrome BR (55 to 62%)                           10.00.08 kg     Carmine              2.00.04 kg     Black 300401         1.00.04 kg     Blue 300308          1.0Mica content of mixture 34.2 to 34.9Pigment content of mixture                   20.1 to 20.8______________________________________ 
    
     200 g of the mixture was mixed with 330 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 28 
     Composition for Nearly Pink Pencil 
     
         ______________________________________                   Wgt %______________________________________1.80 kg    Superfine casting plaster of paris                             45.00.92 kg    Soloron Silver (70%)   23.00.80 kg    Cloisonne Golden Bronze (62 to 68%)                             20.00.20 kg    Timica Copper (51 to 57%)                              5.00.28 kg    Duochrome RY (61 to 67%)                              7.0Mica content of mixture   35.32 to 37.24Pigment content of mixture                     17.76 to 19.68______________________________________ 
    
     200 g of the mixture was mixed with 320 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 29 
     Composition for Apricot Frost Pencil 
     
         ______________________________________                   wgt %______________________________________1.80 kg    Superfine casting plaster of paris                             45.01.16 kg    Coloron Bright Gold (59%)                             29.00.88 kg    Soloron Silver (70%)   22.00.08 kg    Cloisonne Golden Bronze (62 to 68%)                              2.00.08 kg    Ariabel Sienna 300406   2.0Mica content of mixture   33.75 to 33.87Pigment content of mixture                     21.13 to 21.25______________________________________ 
    
     200 g of the mixture was mixed with 330 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 30 
     Composition for Brick Red Pencil 
     
         ______________________________________                   Wgt %______________________________________1.80 kg    Superfine casting plaster of paris                             45.02.20 kg    Cloisonne Rouge Flambe (49 to 55%)                             55.0Mica content of mixture   26.95 to 30.25Pigment content of mixture                     24.75 to 28.05______________________________________ 
    
     200 g of the mixture was mixed with 270 cm 3  bacteriocide and fungicide solution. 
     EXAMPLE 31 
     Composition for Stormy Black/Blue Pencil 
     
         ______________________________________                   wgt %______________________________________1.80   kg     Superfine casting plaster of paris                             40.01.40   kg     MP155 Blue (49%)    35.00.60   kg     Black               15.00.20   kg     Blue                5.0Mica content of mixture   17.15Pigment content of mixture                     37.85______________________________________ 
    
     100 g of the mixture was mixed with 290 cm 3  bacteriocide and fungicide solution. 
     EXAMPLE 32 
     Composition for Twilight Pencil 
     
         ______________________________________                   wgt %______________________________________1.92   kg     Superfine casting plaster of paris                             48.01.60   kg     Woloron Silver (70%)                             40.00.40   kg     Black               10.00.08   kg     Red 300418           2.0Mica content of mixture   28.0Pigment content of mixture                     24.0______________________________________ 
    
     200 g of the mixture was mixed with 300 cm 3  bacteriocide and fungicide solution. 
     EXAMPLE 33 
     Composition for Earth Glow Pencil 
     
         ______________________________________                   wgt %______________________________________1.80   kg     Superfine casting plaster of paris                             45.01.28   kg     MP127 Timiron Gold (57%)                             32.00.40   kg     Soloron Silver (70%)                             10.00.40   kg     Ariabel Umber       10.00.02   kg     Black                3.0Mica content of mixture   25.24Pigment content of mixture                     29.76______________________________________ 
    
     200 g of the mixtures was mixed with 300 cm 3  bacteriocide and fungicide solution. 
     EXAMPLE 34 
     Composition for Sunset Pencil 
     
         ______________________________________                 wgt %______________________________________1.80 kg     Superfine casting plaster of paris                           45.02.20 kg     Timica Copper (51 to 57%)                           55.0Mica content of mixture 28.05 to 31.35Pigment content of mixture                   23.65 to 26.95______________________________________ 
    
     200 g of the mixture was mixed with 250 cm 3  bacteriocide and fungicide solution. 
     EXAMPLE 35 
     Composition for Peacock Pencil 
     
         ______________________________________                 wgt %______________________________________2.00 kg     Superfine casting plaster of paris                           50.01.80 kg     Duochrome RB (48 to 54%)                           45.00.20 kg     Ariabel Blue         5.0Mica content of mixture 21.6 to 24.3Pigment content of mixture                   25.7 to 28.4______________________________________ 
    
     200 g of the mixture was mixed with 240 cm 3  bacteriocide and fungicide solution. 
     EXAMPLE 36 
     Composition for Silver Pencil 
     
         ______________________________________               wgt %______________________________________Superfine casting plaster of paris                 30.0Soloron Silver (70%)  69.0Black Iron Oxide       1.0Mica content of mixture                 48.3Pigment content of mixture                 21.7______________________________________ 
    
     200 g of the mixture was mixed with 450 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 37 
     Composition for Silver Pencil 
     
         ______________________________________               wgt %______________________________________Superfine casting plaster of paris                 35.0Soloron Silver (70%)  64.0Red Iron Oxide         1.0Mica content of mixture                 44.8Pigment content of mixture                 20.2______________________________________ 
    
     200 g of the mixture was mixed with 475 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 38 
     Composition for Silver Pencil 
     
         ______________________________________               wgt %______________________________________Superfine casting plaster of paris                 40.0Soloron Silver (70%)  60.0Mica content of mixture                 42.0Pigment content of mixture                 18.0______________________________________ 
    
     200 g of the mixture was mixed with 400 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 39 
     Composition for Silver Pencil 
     
         ______________________________________               wgt %______________________________________Superfine casting plaster of paris                 55.00Soloron Silver (70%)  45.00Mica content of mixture                 31.50Pigment content of mixture                 13.50______________________________________ 
    
     200 g of the mixture was mixed with 325 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 40 
     Composition for Silver Pencil 
     
         ______________________________________               wgt %______________________________________Superfine casting plaster of paris                 60.00Soloron Silver (70%)  39.00Red Oxide              1.00Mica content of mixture                 27.30Pigment content of mixture                 12.70______________________________________ 
    
     200 g of the mixture was mixed with 300 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 41 
     Composition for Silver Pencil 
     
         ______________________________________               wgt %______________________________________Superfine casting plaster of paris                 65.00Soloron Silver (70%)  34.00Red Iron Oxide         1.00Mica content of mixture                 23.80Pigment content of mixture                 11.20______________________________________ 
    
     200 g of the mixture was mixed with 300 cm 3  of bacteriocide and fungicide solution. 
     EXAMPLE 42 
     Composition for Silver Pencil 
     
         ______________________________________               wgt %______________________________________Superfine casting plaster of paris                 70.0Soloron Silver (70%)  30.0Mica content of mixture                 21.0Pigment content of mixture                  9.0______________________________________ 
    
     200 g of the mixture was mixed with 275 cm 3  of bacteriocide and fungicide solution.