DE2302969C3 - Glassy or crystalline material for photochromic thin layers - Google Patents

Description

ν- ■,. The steam process takes place in this example

Type of cation are present. _{mjt χ up to 14 g of material} i _f, the substrate being one

2. Material according to claim 1, characterized by a distance of about 40 cm to the vapor deposition boat. records that there is 15 to 80 atomic percent bromine. The vapor deposition time is 60 seconds Contains anions. 30 evaporation boats 2 to 5 A are applied.

3. Material according to claim 1, characterized in that there is an almost colorless, slightly gray-tinted, draws that it has a composition, 400 nm thick layer on the substrate. It will which is removed from the recipient within the eutectic mixture of the substrate with the layer, so Two-substance system AgBr - CuBr lies. can the phototropy by exposure with

4. Material according to one of claims 1 to 3, 35 check actinic radiation.

characterized in that it is the light transmission as the spectral In the exposed state

Sensitivity of the photochromic layers is 10% of the substrate glass with layer 10%, in the unexposed

contains sliding additives S or Te. State it is about 60%. When the actinic

5. Material according to one of claims 1 to 4, radiation is switched off, regenerates the exposed characterized in that it is used as the improvement 40 substrate platelet with the layer for starting Additives serving the properties Cation permeability. In the exposed state is the color of the elements Pb, Zr, Si, Mg, Al and / or La of the blue-black layer.

contains. See the table below for more examples

for suitable compositions of the layer material

45 listed. In FIG. 1 is the location of this

In the German patent 21 56 304 a compositions in the three-component system is clarified, vitreous or crystalline material claims that

- in a thin layer on a translucent support table

applied - photochromic properties in the form of “. . , ~ '. "7 ~.

• u · a · »ix ·, Ji Example No. in atomic percent atomic percent atomic

ciner when excited with ultraviolet or short- 50 _Nr / _{Fig x} ^{v H} percent

Increase in extinction due to wave-visible light. Ag Cu Br

hung and after the end of the excitation

Shows a decrease in extinction, and this thereby results in 2 8 47.5

indicates that there is at least one not 3 7 40.0

light-sensitive Me ^{n +} cation species, at least one 55 4 2 32.5

Anion species and at least one Me ¹ "" ¹ '+ cation 5 9 25.0

art, where η can have the value 1, 2 or 3. 6 10 17.5

It has now surprisingly been found that thin 7 11 10.0

Layers with particularly favorable phototropic and 8 12 2.5

performance properties are achieved 60 9 14 35.0

can if the material that is in thin layer 10 Ϊ5 22.5

applied on a translucent carrier 11 16 10.0

has the following composition: 12 17 40.0

13 18 35.0

5 to 58 atomic percent silver cations as light 65 14 19 30.0

sensitive cations, 15 21 10.0

8 to 85 atomic percent chlorine and / or erom 16 22 15.0

anions. 17 23 25.0

2.5 50.0 10.0 50.0 17.5 50.0 25.0 50.0 32.5 50.0 40.0 50.0 47.5 50.0 32.5 32.5 38.75 38.75 45.0 45.0 20.0 40.0 30.0 35.0 40.0 30.0 30.0 60.0 23.33 61.67 16.67 53.33

Table (continued)

example

No. in
Fig. 1

Atomic percent
Ag

Atomic percentage atomic percentage Cu Br

18th 49.2 9.2 41.6 19th 56.4 4.9 38.7 20th 62.6 1.1 36.2 21 40.9 14.2 44.9 22nd 31 = 1 20.1 48.8 23 5.0 30.0 65.0 24 36.16 13.84 50.0 25th 28.68 21.32 50.0 26th 19.5 27.0 53.5 27 5.4 35.5 59.1 28 23.0 39.0 38.0 29 45.0 10.0 45.0 30th 5.0 30.0 65.0 example 18th

61.68 percent by weight AgBr, 38.32 percent by weight CuBr.

Melting conditions:

800 ⁰ C; 1min; Quartz crucible; Electric furnace; Bromine atmosphere.

Evaporation conditions:

10- ⁵ Torr, 4 A, 0.8 g of substance, 40 cm distance, substrate B 270th

Phototropic of the layer:

Output transmission 65%, saturation transmission after 15 min of actinic irradiation 30%, half-value of regeneration 18 min.

Example 19

65.48 percent by weight AgBr, 34.52 percent by weight CuBr.

Melting Conditions:

800 ⁰ C; 30 see; Pt crucible; Induction furnace, normal atmosphere.

On steam conditions:

10- ⁵ torr; 2 A, 1.0 g substance, 40 cm distance, substrate Tempax.

Phototropic of the layer:

Initial transmission 60%, saturation transmission after 15 min of actinic irradiation 12%, half-life of regeneration 200 min.

Example 20

40.85 percent by weight CuCl, 59.15 percent by weight AgCl.

Melting Conditions:

720 ⁿ C; 2min; Quartz crucible, electric furnace, chlorine atmosphere.

Evaporation Conditions:
As in example 1.

Phototropic of the layer:

Initial transmission 80%, saturation transmission after 15 min of actinic irradiation 48%, Half-life regeneration 4 min.

Example 21

29.27 percent by weight CuCl ₂ , 70.73 percent by weight AgEr.

Melting Conditions:

675 ° C; 1min; KeTamik crucible, electric furnace, normal atmosphere.

Evaporation Conditions:

4 x 10 " ⁶ Torr; 4 A; 20 g substance, 40 cm distance, substrate plastic (transparent).

Phototropy of the layer:

Initial transmission 70%; Saturation transmission after 15 min of actinic irradiation 18%; Regeneration half-life 120 min.

It has been found that a mixture of the previously not melted to a homogeneous melt individual components fractionated in the vapor deposition and does not bring such favorable results.

The layers vapor-deposited on a substrate

can also be covered with a vapor deposition _{glass, with SiO 2} , magnesium fluoride or thorium fluoride to improve the scratch resistance. However, this does not improve the phototropy.

For the purpose of improving properties, e.g. B. the Kraufestigkeit of the layer are further Additions to the material according to the invention for the coating are possible, but these should be used to achieve this sufficient phototropy, if possible, remain below 35 percent by weight. So z. B. Ions of the elements Pb, Zr, Si, Mg, Al and / or La in connection with the anions according to the invention the melting process of the mixture readily additive to 100 percent by weight of z. B. in the Add the compositions (syntheses) listed in the table, but the phototropy is proportional to the amount of additives is decreased.

As an example of such additives, in Example 22, based on the composition of Example 19, Magnesium ions added to the anion according to the invention.

Example 22

65.48 percent by weight AgBr, 33.52 percent by weight CuBr.

100.00 percent by weight, 12.00 percent by weight MgBr ₂ .

Melting Conditions:

88O ⁰ C; 60 see; Quartz crucible; Gas stove, normal atmosphere.

On steam conditions:

10- ⁵ torr; 4 A; 1.0g substance, 40cm distance, substrate plastic.

Phototropy of the layer:

Initial transmission 65%, saturation transmission after 15 min of actinic irradiation 19%, Half-life of regeneration 200 min.

It was also found that additives known from photochemistry to shift the spectral sensitivity, such as B. S or Te, the same or similar effect when used in the layers according to the invention as in photochemistry.

Investigations of phototropy, e.g. B. on the cut

CuDr - AgBr of the three-component system Cu - Ag - Br, resulted in the in F i g. 2 regeneration rates (increase in transmission in Percent after 10 min residence time without optical stimulation). In Fig. 3 are those for a standard exposure with a 150 W xenon lamp XBO (distance 25 cm from the sample) transmission values measured in percent after an exposure time of 15 min (Saturation transmission in percent) as a function of the mol percent AgBr of the examples AgBr - CuBr section in the three-substance system Cu - Ag - Br shown.

It has been found that especially in the area of eutectic mixing of the two-substance system AgBr - CuBr (W. J ο s t and S. v. S a 1 m u t h [Z. phys. Chcm. New series, vol. 16, 1958, p. 277 to 280]) in the range between 50 and 70 mol percent AgBr, particularly favorable photochromic properties appear. It is assumed that the multiphase crystalline precipitates from which dit Layers according to the invention are built up with their ίο phase boundaries precisely in the eutectic, at least one embodiment however, in the area of multiphase, they have a favorable influence on the phototropic properties.

For this purpose 2 sheets of drawings

Claims (1)

♦ *> ! 2 2 to 60 atomic percent copper cations, the highest increase and after termination of the excitation The invention is illustrated in the following example shows taking place extinction lowering, and explains. from at least one non-photosensitive Me ^{n +} - io B eis ρ ie 1 1
Type of cation, at least one type of anion and at least one light-sensitive MeO - ^ - Kat- For the production of a photochromic layer material ion type, where η has the value 1, 2 or 3 in the Ag —Cu-Br system, 70.85 weight can have, according to patent 21 56 304, thereby percent AgBr and 29.15 percent by weight CuBr, g e k e η η ζ e i c h η e t that the material following 15 both laboratory quality (99%), mixed in a mortar, in Composition comprises: a quartz crucible at 800 ⁰ C to a homogeneous one ,,. , _{0 A. c} . ",. . ..,. Melted, this poured into a steel mold 5 to 58 atomic percent silver cations as], cht- ^ _n ^ _{cooled to room} temperature. ' c u- _oc sensitive cations Subsequently, the material with the mortar 8 to 85 atomic percent of chlorine and / or bromine ^ ™ _{ze 'rt (<0> 5 nm} particle diameter) and in the 2 to 60 "ocent copper cations, the tungsten boats of a commercially available vapor deposition K3? Rv * .L ± ™ * J ^ Z ^V - "ζ? Ellung of the photochromic layer is this