DE3437989C1 - Powder stick and process for the production thereof - Google Patents

Abstract

The powder stick according to the invention is produced by compacting a dry-prepared refill composition containing the pigment and a sinterable, preferably thermoplastic binder, within the stick shaft casing and subsequent controlled heat treatment of the compacted refill composition. During the heat treatment, the binder particles fuse onto restricted areas of the surface of the pigment particles and as a result, after cooling, are firmly incorporated into the refill structure. Since the pigment particles are not completely encased by the binder, the refill has a good ability to deliver the pigment. Because of the dry processing of the refill composition and the production of the refill in the shaft casing, no calibration problems result.

Description

In the course of this procedure, the pigment particles are replaced by the complete melting of the binder with this enveloped. This will make the Delivery (pay-off) of the pigment to the skin is impaired. In the DE-OS 33 02 803 described cosmetic refill for a powder pen eliminates this disadvantage avoided that an in finely divided form present plastic material is incorporated, the Particles are larger than the base materials Have hardness. The addition of water gives the mixed with a water-soluble binder Lead mass its deformability, so that it can be extruded into the desired stick shape can be brought, which is followed by a drying process. In the case, that the mine produced in such a way are introduced into a shaft sleeve should, there arises what was mentioned at the beginning in connection with the prior art Calibration problem.

The invention is based on the object of providing a powder pen to propose, on the one hand, produced without the use of a liquid medium can be, but on the other hand in comparison to that described in DE-OS 28 52 988 Pen has better delivery characteristics.

In solving this problem, the invention proceeds from a powder pen from, which has a shaft sleeve and a mine enclosed by this, in which the powder pigment particles by means of a sinterable binder to form a compact body are held together. In the case of such a powder pen, the invention consists in that the compact is produced in the shaft sleeve itself and the pigment particles by melting the binder particles onto limited areas of the surface the pigment particles are held together.

There is therefore no prefabricated lead in the pen according to the invention before. Rather, this is generated in the shaft sleeve itself, which will be discussed below is described in more detail. Although it is also in the subsequently published DE-OS 33 27 771 described the creation of a mine in the case itself, but it is a flowable, meltable lead mass. According to the present invention however, the formation of the mine in the shaft sleeve is possible in that the Mine mass is not processed with a liquid medium. Thus arises neither does the calibration problem mentioned at the beginning. It is now possible without special additional effort, powder pens with leads of different strengths to manufacture.

Another special feature of the invention is the fact that the Powder pigment particles by a process comparable to a sintering process in the mine structure are firmly integrated and only part of the surface the pigment particles are covered with the (sintered) binder. This sub-area should preferably be less than 50% of the total surface. For this proves it is advantageous if the pigment particles are significantly larger than the particles of the binder. Since the pigment particles are not necessarily spherical, should be the particle size of the pigment measured according to its largest dimension are substantially greater than that of the binder particles, preferably twice that be.

Since in the powder stick according to the invention, the pigment particles are not are enveloped by the binder, so their surface over a relatively large If the area is free, so to speak, the pencil lead has a particularly good dispensing ability for the pigment.

In the drawing are the differences between the structure of a according to the state of the art (DE-OS 28 52 988) manufactured powder pen (Fig. 1) and a powder pen (Fig. 2) according to the invention is illustrated schematically. While in the known stick, the pigment particles I from the binder II completely are encased (Fig. 1), remain essential in the pen according to the invention (Fig. 2) Areas of the surface of the pigment particles I uncovered by the binder II. The connecting bridges formed by the binder are shown in FIGS. 1 and 2 marked with lll.

The pigment particles are firmly integrated into the lead structure according to the invention in that the mine mass compacted in the shaft sleeve subjected to a heat treatment for such a time and at such a temperature becomes that the surface of the fine binder particles as in a sintering process is melted - without completely melting into a liquid - and the melt fraction of the binder particles with a limited area of the surface the pigment particles come into such intimate contact that the Binder particles can take place on the pigment particles, so that after solidification the proportion of melt in the course of the cooling of the mine mass is a very strong link is present between the binder and pigment particles. Where binder particles touch, there is also a sintering process between them Gluing instead.

For the purposes of the invention, preferred binders are used High molecular weight organic substances are considered, which have a melting point or melting range between 600C and 1200C. These include, in particular, thermoplastic polymers. Examples of binders that can be used according to the invention are: polyethylene, Polypropylene, polyvinyl acetate, polyvinyl acetals, polyglycols, polyether, polytetrafluoroethylene, low molecular weight polyvinylpyrrolidone, ketone resins; also high molecular weight waxes such as polyethylene glycols, ozokerite; Resins based on unsaturated hydrocarbons; Condensation resins such as polyamide, phthalate, maleate and sulfonamide resins; Natural resins such as dammar, shellac, coumarone resins, and rosin modified resins.

In principle, sinterable inorganic materials can also be used such as MgCl2 6 H20, FeSO4 - 7 H2O; AlNa (SO4) 2 12 H2O for the production of the invention Sticks are used, of course also in this case on the skin tolerance to pay attention to.

Of course, a mixture of several binders can also be used can be used.

The proportion of binder in the lead mass should be between 2-15 % By weight, preferably 8-12.

For manufacturing reasons, the particle size of the binder powder should be as uniform as possible, which affects the flowability of the binder powder has a beneficial effect. The individual binder particles can have a size of 0.02-5y, preferably 0.2-2 u. In contrast, the powder pigment particles should, such as already mentioned, have a much larger dimension.

The powder pigment is preferably made of mica (coated and / or uncoated). However, other color pigments such as iron oxides, manganese violet, Ultramarine, titanium dioxide and permitted organic pigments such as carmine and Milori blue, optionally together with mica, can be used. The invention does not, of course, exclude the addition of pigments and binders still other solids are incorporated into the mine mass, as was also done by is known from the well-known powder pens. These include B. talc, kaolin, Metal soaps, finely divided silica. The A- binding this Additives to the lead structure are made in the same way as with the powder pigment particles.

So that there is a good connection between the lead and the barrel or liability comes about, it proves to be expedient to use a sleeve, whose inner wall is as rough as possible, so that it is pressed into the sleeve Mine mass can equally interlock with the inner wall. To this end you can on the inner wall of the shaft sleeve compared to such roughness even more pronounced Depressions or projections be worked out, in or around which the lead mass in or

being pushed around. The shaft sleeve is advantageously made of Wood. But it can also be made of other materials that are used in the for temperatures applied during the sintering process retain their shape.

In the method for producing the pencil according to the invention, basically proceeded as follows: From the powder pigment and the binder as well any additives that may still be used are mixed using a stirrer an intimate mixture prepared dry. This comes on the funnel of a dosing device, by means of the clockwise a defined, d. H. the compact filling of a single Shank sleeve filled into the cylinder of a pressing device corresponding amount will. A piston can be introduced into the cylinder space from one end of the cylinder. The filling end is inserted into the opening provided at the other end of the cylinder of the shaft sleeve to be loaded, the other one - possibly a truncated cone elaborated - end is supported against an abutment that the sleeve during of the filling process fixed in place and also the one sleeve opening against the Sealed outlet of mine mass.

When the plunger is retracted into the cylinder, the in this existing filling quantity pressed into the shaft sleeve. The pressure only needs 0.5-2 bar. After the shaft sleeve has been filled, it becomes the device removed, after which again an empty tube inserted into the device for filling and the described working process is repeated.

It goes without saying that for mass production several of the devices described are combined to form an overall system, with then a single metering device assigned to a plurality of pressing devices can be.

The shaft sleeves filled with the lead compound are placed in an oven, which is heated to a temperature adapted to the binder used, in which the pins are indeed necessary for the course of the sintering process, but only a sufficient period of time remains. After removing the pens from these are cooled in the furnace and then, if necessary, to expose the mine application tip processed. However, it is also possible during the compaction of the mine mass an exposed lead tip to be molded at the same time within the shaft sleeve. For this all that is required is a corresponding shaping of the abutment against which the shaft sleeve is supported during compaction.

Those given in the following examples with their composition Mixtures were prepared according to the procedure description above and processed into the mine.

Example 1 34.0 parts by weight of mica powder (grain size 20-60) 10.0 Parts by weight talcum powder 12.0 parts by weight Mg stearate 8.0 parts by weight Al2O3 12.0 parts by weight Ultramarine blue 14.0 parts by weight TiO2 10.0 parts by weight polyvinyl acetate powder with a melting range 85-90 "C and a grain size of 0.07-0.5 lt.

Example 2 19.0 parts by weight of talc 16.0 parts by weight of kaolin 12.0 parts by weight Ca stearate 45.0 parts by weight coated mica 8.0 parts by weight coumarone resin Melting range around 950C and a grain size range of 1-5 according to Example 3 38.0 parts by weight Mica 10.0 parts by weight Zn stearate 9.0 parts by weight finely divided silica (Aerosil) 30.0 parts by weight of iron oxide pigment 12.0 parts by weight of polyethylene powder with a grain size from 2-5 lt and a melting range of 105-110 "C.

Example 4 16.0 parts by weight of kaolin 12.0 parts by weight of calcium stearate 20.0 Parts by weight of Mg carbonate 37.0 parts by weight of coated mica 15.0 parts by weight of polyethylene glycol with a melting range of 60-65 "C and a grain size of 0.5-2 lt Example 5 35.0 parts by weight mica 14.0 parts by weight talc 12.0 parts by weight Mg stearate 4.0 parts by weight Ca carbonate 23.0 parts by weight manganese violet 2.0 parts by weight carmine 10.0 parts by weight powdered and sieved sulfonamide resin with a melting range of 62-70 "C and a grain size of 0.5-2 lt.

Claims (13)

Claims: 1. Powder pen with one enclosed by a shaft sleeve Mine, which is a powder pigment, preferably mica, and one of the pigment particles too Sinterable, preferably thermoplastic, which holds together a compact body Contains binder, characterized in that the compact body is in the sleeve itself is produced and the pigment particles by fusing the binder particles are held together on limited areas of the surface of the pigment particles. 2. powder pen according to claim 1, characterized in that the thermoplastic Binder a high molecular weight substance with a melting point or melting range is between 600 and 1200 C. 3. Powder pen according to claim 2, characterized in that that the binder is a polymer. 4. powder pen according to claim 2, characterized in that the binder is a wax. 5. powder pen according to claim 1, characterized in that the binder is an inorganic substance that can be sintered between 600 and 1200 C. 6. Powder pen according to one of the preceding claims, characterized in that that the proportion of binder in the lead mass is 2-15% by weight. 7. powder pen according to claim 6, characterized in that the binder content in the lead mass is 8-12% by weight. 8. Powder pen according to one of the preceding claims, characterized in that that the particle size of the pigment measured according to its largest dimension is significantly higher than that of the binder. 9. powder pen according to claim 8, characterized in that the particle size of the pigment is at least twice that of the binder. 10. Powder pen according to claims 8 or 9, characterized in that that the size of the binder particles is between 0.02-5 and preferably between 0.2-2 11, lies. 11. Powder pen according to one of the preceding claims, characterized in that that the binder particles have a largely uniform grain size. 12. Powder pen according to one of the preceding claims, characterized in that that the binder particles cover less than half the surface area of the pigment particles are fused to this. 13. A method for producing a powder stick according to any one of the preceding Claims, characterized in that the dry processed, powder pigment and Mixture containing binding agent for the lead mass in one of the compact filling an amount corresponding to a single shaft sleeve pressed into the shaft sleeve, then the lead mass located in the shaft sleeve is subjected to a heat treatment in which the binder particles on their surface and on the surface the pigment particles melt and then the stick is cooled. The invention relates to a powder stick having one of one Shaft sleeve enclosed mine, which is a powder pigment, preferably mica, and contains a binder that holds the pigment particles together to form a compact body, and to a method of making such a pen. Known pens of this type are made in such a way that the powder pigment and the binder and the accompanying or possibly still present. Auxiliary substances using a liquid medium a plastically deformable Mixture prepared, this pressed in a special tool in the form of a stick and the liquid medium from the pen body through a subsequent drying process Will get removed. The pigment particles and the possibly. any other accompanying substances used by the in the liquid Medium initially dissolved or swollen binders to a more or less firmly held together. In many cases, water-soluble binders such. B. Cellulose derivatives (esters), use so that the stick compound is prepared with water can be and thus with the use of organic solvents for the Problems associated with environmental protection are eliminated. The manufacturing method described has various disadvantages. First once brings the temporary incorporation of a liquid medium into the pencil compound and its subsequent removal entails additional effort. When using bacterial contamination problems arise from water. Of particular importance but are the difficulties associated with an exact calibration of the pin cross-section, that is because due to the incorporation of the liquid medium into the pencil compound initially a swelling and, when the liquid is removed later, a shrinkage takes place. However, an exact calibration of the pen body is necessary, if this is to be introduced as a mine in a shaft sleeve, which is often because of the insufficient intrinsic strength of the pen body, but also from handling of the pen related practical reasons is desirable. The calibration problem is exacerbated in such cases in which shaft sleeves with different internal cross-sections with a pin body should be charged. From DE-OS 28 52 988 a solid powder pen is known in which Production can be dispensed with a liquid medium, so that here too the aforementioned disadvantages and difficulties do not occur. In the manufacture of this pen, the procedure is that initially the powder pigment with polyethylene as a binder in a fluidized bed powder mixer intimately mixed with one another with melting of the polyethylene and the resultant Mixture is cooled spontaneously, after which the present as granules particles des Mixture in a hammer mill at a temperature below 800 C to fine particles are ground and from this in a tool at an impact pressure between 3.0 and 8.0 kg / cm 2 of the stick body is molded.