Diffusing reflector manufacturing method

FIELD: measurement equipment.

SUBSTANCE: method involves shaping of a reflector based on organic plastic material and non-organic substance with reflection coefficient of not less than 0.9 by preparing a mixture of initial components under pressure. As organic plastic material there used is a mixture of fluorine and polycarbonate; as non-organic substance - titanium dioxide, at the following component ratio, wt %: polycarbonate 100; fluorine 3.5-5.0; titanium dioxide 0.5-1.0. Forming can be performed by pressing at pressure of 800 to 1500 atm and at temperature of 240-270°C to thickness of not less than 2 mm or by casting at pressure of 750 to 1500 atm and at temperature of 280-290°C to thickness of at least 2 mm. Polycarbonate with melt flow-behaviour index of 2-60 g/10 min can be used as polymer material.

EFFECT: enlarging processing methods, temperature interval of processing, reducing cost and material consumption.

4 cl, 1 dwg

 

The invention relates to optics and can be used in the photometric devices to provide diffuse reflection of the detected radiation, the interior surface integral photometers, etc.

A known method of manufacturing a diffuse reflector comprising forming a reflector on the basis of inorganic material with a reflectivity of not less than 0.9, in particular, barium sulfate, and organic plastic material is polyvinyl alcohol. (Huminicki YEAR, Sahnovsky M., Cat A.F., Konecki MG Spectrophotometric characteristics of the coatings of paints on the basis of barium sulphate with polyvinyl alcohol. Journal of applied spectroscopy, 1979, CH, No. 1, p.113-116).

In the author's certificate of the USSR SU 1670653 G02B 5/20, 5/02, publ. 15.08.1991, the applicant Chernivtsi state University, offered to produce a diffusely scattering reflector with high mechanical strength, reduced diffuse reflectance and high chemical resistance by pressing under a pressure of 10-50 ATM powder of PTFE with a particle size of 0.25-1.0 μm to a thickness of not less than 7 mm

A method of manufacturing a diffuse reflector with the same author's certificate SU 1670653 optical characteristics that is closest to the technical essence and the achieved effect to the proposed, with the costs in the formation of the reflector on the basis of organic plastic material, in particular, the fluoropolymer and the inorganic light-diffusing optical material with a reflectivity of not less than 0.9 when the content of PTFE is not less than 10% may. by pressing under a pressure of 10-50 bar to the thickness of the product not less than 5 mm (inventor's certificate SU 1670654 G02B 5/20, 5/02, publ. 15.08.1991, of the same applicant, declared and published simultaneously with SU 1670653); the inorganic material with a reflectivity of not less than 0.9 in accordance with the examples used barium sulfate or magnesium oxide.

Both developments provide almost the same value of diffuse reflectance at wavelengths from 0.4 to 1.2 microns.

The disadvantages of the known methods is the possibility of processing only by a pressing method, a significant amount of material for the manufacture of the reflector and the high cost of the feedstock. Negative factor in the use of PTFE is also the difficulty in the disposal of waste fluoropolymers, the number of which to date is estimated at thousands of tons. High chemical, thermal, climatic resistance of PTFE make it wastes almost eternal; their simple incineration requires significant energy costs and is accompanied by the release of harmful products.

The technical problem of the invention consists in the improved technology is licnosti in the manufacture of the reflector and improve economic and environmental performance of the process.

The technical result consists in the extension processing methods, temperature interval processing, reducing the cost and material consumption, is achieved in that in the method of manufacturing a diffuse reflector comprising forming a reflector on the basis of organic plastic material and inorganic substances with a reflectivity of not less than 0.9 forming a mixture of the initial components under pressure, as organic plastic material using a mixture of PTFE and polycarbonate, as the inorganic substance is titanium dioxide in the following ratio of components, parts by weight:

Polycarbonate100
Teflon3.5-5.0
Titanium dioxide0.5-1.0

When the molding material by pressing the latter is carried out at a pressure of from 800 to 1500 atmospheres at a temperature of 240-270°C to a thickness of not less than 2 mm, and when the molding method of molding the latter carry out under pressure from 750 to 1500 atmospheres at a temperature of 280-290°C to a thickness of at least 2 mm.

As the polymer material of which is made of a diffuse reflector, using a mixture of polycarbonate with pok is an indicator of the fluidity of the melt 2-60 g/10 min in powder form, preferably with a particle size of about 300 microns and PTFE in powder form with a particle size of about 1 micron.

It makes possible the use of polycarbonate with a degree of crystallinity of from 10 to 40%, in particular, domestic polycarbonate brand Diflon with a molecular weight of 22,000. When a greater degree of crystallinity of polycarbonate material provides improved reflectivity. However, the use of crystalline polycarbonate is limited by the duration of the crystallization process (heating at a temperature of 190°C for weeks or more).

Of the famous brands of PTFE is used mainly fluoroplastic-4, although best results are compatible with polycarbonate shows PTFE-42, which is, however, more expensive product.

As the inorganic substance use titanium dioxide, preferably, rutile modification with a reflectivity of about 0.98, mark Ti-Pure R-105 DuPont.

The invention is illustrated by the following examples:

Example 1. To obtain a diffuse reflector powders polycarbonate Panlite L 1225 WP 100 parts by weight, 3.5 parts by weight of PTFE-42 and 0.5 parts by weight of titanium dioxide Ti-Pure R-105 DuPont stirred and poured the mixture in the matrix; punch, representing a parallelogram with dimensions 2×20×40 mm2insert in the matrix is pressed poluchenno the system at a pressure of 800 bar. and at a temperature of 260-270°C.

Example 2. To obtain a diffuse reflector powders polycarbonate Panlite L 1225 WP 100 parts by weight, 4.0 parts by weight of PTFE-42 and 1.0 parts by weight of titanium dioxide Ti-Pure R-105 DuPont, stirred and poured the mixture in the matrix; punch, representing a parallelogram with dimensions 2×20×40 mm2insert in the matrix extrude the resulting system at a pressure of 1300 bar. and at a temperature of 250-260°C.

Example 3. To obtain a diffuse reflector powders polycarbonate Panlite L 1225 WP 100 parts by weight, 5.0 parts by weight of PTFE-42 and 0.7 parts by weight of titanium dioxide Ti-Pure R-105 DuPont, stirred and poured the mixture in the matrix; punch, representing a parallelogram with dimensions 2×20×40 mm2insert in the matrix extrude the resulting system at pressures up to 1500 bar. and at a temperature of 240-250°C.

Example 4. To obtain a diffuse reflector powders polycarbonate Panlite L 1225 WP 100 parts by weight, 4.0 parts by weight of PTFE-42 and 0.7 parts by weight of titanium dioxide Ti-Pure R-105 DuPont, stirred and poured into the hopper of automatic machines ALLROUNDER 320K 700-250; injection pressure of 1500 atmospheres. and at a temperature of 280-290°C to form the product in the form of a disk with a diameter of 100 mm and a thickness of 2 mm.

Figure 1 shows the spectral dependence of the reflection coefficient of the reflector obtained according to example 2, in the region of wavelengths from 0.4 to 1.1 microns.

When used for the manufacture of diffuse about what rajatila mixture components without inorganic substances with a reflectivity of not less than 0.9 is not provided spectral reflectance of the reflector is at least 0.9, and is 0.80 (curve 2, figure 1).

As already noted, the proposed method can produce the reflector is not only pressing, but also by the method of processing by injection molding and extrusion.

Reflector made in accordance with the proposed method significantly outperforms the reflector of the prototype in terms of material consumption: reflectors, in accordance with the invention, are made of a material sample thickness not less than 2 mm, and in accordance with the invention of the prototype of the claimed thickness 7 mm

In addition, the raw materials for the prototype exceeds the price of raw materials in accordance with the invention, more than 4 times (the cost of fluoropolymer production Kirovo-Chepetsk about 950 rubles/kg, the cost of PC production "Kazanorgsintez" 250 RUB/kg).

1. A method of manufacturing a diffuse reflector comprising forming a reflector on the basis of organic plastic material and inorganic substances with a reflectivity of not less than 0.9 forming a mixture of the initial components under pressure, characterized in that as an organic plastic material using a mixture of PTFE and polycarbonate, as the inorganic substance is titanium dioxide in the following ratio of components, parts by weight:

td align="left"> Polycarbonate
100
Teflon3,5-5,0
Titanium dioxide0,5-1,0

2. A method of manufacturing a diffuse reflector according to claim 1, characterized in that the shaping is done by pressing at a pressure of from 800 to 1500 atmospheres and a temperature of 240-270°C to a thickness of at least 2 mm.

3. A method of manufacturing a diffuse reflector according to claim 1, characterized in that the shaping is done by casting under pressure from 750 to 1500 atmospheres at a temperature of 280-290°C to a thickness of at least 2 mm.

4. A method of manufacturing a diffuse reflector according to any one of claims 1 to 3, characterized in that the polymer material can be applied to polycarbonate with a melt flow index 2-60 g/10 min



 

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FIELD: physics.

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14 cl, 2 tbl, 8 ex

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