DE1494080A1 - Process for protecting light-sensitive materials - Google Patents

Description

J.R.GEIGYA.G. . _ * H94080

Dr. F. 7'jmstefη - Df. E. Assmann ""

Dr .S .. Kre.ii-jsberger Bwel 16 (Switzerland) patent attorneys

Munich 2, Bräuhausetraß 4 / III Process for slitting photosensitive materials

The present invention relates to a method for Protect light-sensitive materials, as well as industrial product which, using a light stabilizer of the formula I below, is protected from the harmful Exposure to light, especially UV rays, protected materials.

It was found that 1-hydroxyxanthone compounds Effectively protect light-sensitive materials from the harmful effects of light. Compounds of the general formula I are particularly suitable.

OH

(D

In this formula mean

S ₁ and 83 are each hydrogen, an ate * · «· aliphatic group, preferably the methyl, atthyl, n-propyl or isopropyl or the η-butyl, Iaobutyl or tert-sutyl group or halogen, preferably chlorine but also bromine, where S _{3 is} advantageously hydrogen

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S ₂ and S _{4 are} each the same as S ₁ and S ₃ or a further hydroxyl * or a preferably low molecular weight aliphatic ether group, such as d} .e methoxy, ethoxy, propoxy, butoxy, β-hydroxyethoxy or ß-hydroxypropoxy group, where S _{4 is} advantageously hydrogen and η and m each have an integer index of 1 to 2.

1-Hydroxyxanthone compounds of the general formula I which can be used according to the invention are obtained if, for example

2-hydroxybenzene-1-carboxylic acid compounds of the general Formula II

COOH

S ₄ > ^ OH

in which S ₃ , S ₄ and η denote what is stated under formula I, with 1,3-dihydroxybenzene compounds dtr general formula III

(ΠΙ)

in which S ₁ , S ₂ and m have the meaning given under formula I, distilled at ordinary pressure, optionally in the presence of condensing agents such as acetic anhydride.

Even when these starting materials are heated in the presence of water-binding condensing agents such as phosphorus oxychloride or anhydrous zinc chloride, expediently to a temperature

909816/0731 BATH ORIGINAL

U94080

from; -50-IpO ⁰ C, 1-hydroxyxanthone compounds which can be used according to the invention are formed. 1-Hydroxyxanthone compounds containing ether groups are obtained, for example, from polyhydroxyxanthone compounds by alkylation under customary conditions, ie by alkaline condensation with aliphatic halides, sulfuric acid esters or half-esters.

Thanks to their protective effect through strong absorption in the UV spectrum, 1-hydroxyxanthone compounds of the general formula I which can be used according to the invention are either incorporated into the light-sensitive carriers, advantageously in small amounts of 0.001-5 ^, in particular in amounts of 0.01-1 $, of the carrier material, or light-sensitive materials are provided with a protective layer which contains the UV absorber and is itself stable and is lightfast.

As a carrier material in which 1-hydroxyxanthone compounds of the formula I are incorporated, polymers are primarily suitable, especially fully synthetic polymers, e.g. addition, in particular vinyl polymers, such as polyvinyl chloride, polyvinylidene chloride, polymers of styrene and dienes, as well as derm copolymers, polyethylene, polypropylene, polyacrylic compounds, -ins- ■ special · polymethyl methacrylate, or! Condensations Dolymer, · ,, like e.g. polyester, or mixed polymers, such as ζ · Β. Polyesterharteι also natural polymers, or their synthetic Modifications such as cellulose, cellulose esters and ethers. Incorporation of the 1-hydroxyxanthone compounds into them Polymers happens. - Depending on the type of polymer, by incorporating at least one 1-hydroxyxanthone compound of the formula I and possibly further additives, such as plasticizers and

909816/0731

BATH ORIGINAL

Antioxidants, heat stabilizers and pigments, in the melt according to the methods customary in the art before or during the shaping, or by dissolving in the corresponding monomer before the polymerization, or by dissolving the polymer and the UV absorber in solvents and subsequent evaporation the latter.

According to the invention, light-sensitive materials are also equipped a protective layer, which contains the UV absorption> ei \, see above this happens, for example, by the fact that the photosensitive material with a protective layer containing at least one 1-hydroxyxanthone compound of the formula I, e.g. with a Varnish, paints, or that it is covered with - appropriately film-like - structures containing such light stabilizers. In In these two cases, the amount of light stabilizers added is advantageously $ 10-30 (based on the protective layer material) for protective layers less than 0.01 mm thick and 1-lOjC for Protective layers from 0.01-0.1 mm thick.

1-Hydroxyxanthone compounds of the formula I which can be used according to the invention are colorless to pale yellowish, depending on the substitution. Thus, 1-hydroxyxanthone compounds of the general formula I, in which S ₂ denotes a further hydroxyl or ether group and S ₄ denotes hydrogen, a lower aliphatic group or halogen, have only a very slight yellowish color of their own and are very lightfast. They are therefore suitable for protecting those substances in which a noticeable coloration by the protective agent is undesirable, for example for protecting transparent, clear foils. As a result of their high lightfastness, the light protection they provide is very durable. 909816/0731

ORIGINAL BATHROOM *

1-hydroxyxanthone compounds of the general formula I,

in which both Sg and S ₄ each represent a further hydroxyl or an ether group are practically colorless. On the other hand, their lightfastness is somewhat lower than that of the 1-hydroxyxanthone compounds in which S ₄ denotes hydrogen, a lower aliphatic group or halogen.

1-Hydroxyxanthone compounds in which Sg and S ₄ each represent hydrogen, a lower aliphatic group or halogen, absorb particularly well in the long-wave range in the UV spectrum. They are therefore used advantageously where the harmful influence of long-wave UV rays on UV-sensitive materials is to be avoided, but a slight yellowing does not interfere, for example in certain wood coatings. -

The following examples illustrate the effect of the compounds used according to the invention. Parts are in it Unless otherwise noted, understood as parts by weight.

The temperatures are given in degrees Celsius. Gewiohtsteile

3 relate to parts of volume as grams to cm.

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example 1

Commercially available polyester resin (IC 312 Standard Polyester Resin from Interchemical Corporation, New York, USA) is mixed with 2 $> benzoyl peroxide paste (50%) and O.I76 one of the substances given in the table below, between glass plates at 70 ° for 3 hours. polymerized and then post-cured at 110 for 2 hours. Optically flawless, rectangular test specimens are cut out of the transparent 2 mm thick plates obtained in this way and exposed in the fadeometer. Then after 0, 500 and 1000 hours, the transmission of the individual plates is measured at 500 m ^. The measured values are compiled in Table 1.

A similar improvement in lightfastness is achieved in polyester resins which have been produced by vinyl polymerisation of a mixture of 70 % polyglycol maleate and 30% methyl methacrylate by adding 0.2% light stabilizers according to Table 1 before polymerisation with benzoyl peroxide.

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ORIGINAL INSPECTED

Table 1

H9408

No. Light stabilizers Transmis
for light
unexposed sion in %
from 500 ε
belicl
500 hours ψ
itet
1000 hours Sol
% ι
1OC 1 1-hydroxyxanthone 89.0 88.5 88.0 2 l-hydroxy-4-chloro-xanthone 89.6 88.2 88.2 .3 1-hydroxy-3,7-dimethyl-xanthone 90 89.2 88.5 4th l-hydroxy-2,4-di-tert-butyl-
xanthone 89.0 88.0 86.5 ' 5 ¹ l-hydroxy-5-methyl-xanthone 89.5 89.5 88.5 6th 1-hydroxy-7-methy1-
xanthone -. 89.8 89.5 88.2 7th 1,3-dihydroxyxanthone. 89.5 88.5 87.5 8th l-hydroxy-4-methyl-
xanthone 89.2 87.5 87.0 9 l-hydroxy-3-methoxy- "
xanthone 89.8 89.5 89.5 10 1-hydroxy-3- (β-hydroxy-
ae thoxy) -xanthone 89.5 89.0 89.0 • 11 1,3,6-trihydroxy
xanthone 89.8 88.1 87.2 12th 1,6-dihydroxy-xanthone 90.0 88.5 88.5 13th l-hydroxy-3,6-di- (ß-hydroxy-
ae thoxy) -xanthone 89.0 87.0 86.6 14th Without, (blind test) 89.5
B. 84.0 62.0

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ORIGINAL INSPECTED

'H94080

As can be seen from Table 1, the transmission falls of a test specimen which contains a light stabilizer mentioned in Table 1, decreases much less strongly with the exposure time than that of a test piece without content of the above light stabilizers, which is the light protection effect of the 1-hydroxyxanthone compounds which can be used according to the invention for polyester-containing polymers demonstrated.

Connections No. 4, 10 and 13 in Table 1, which are not yet known, are produced according to the following process!

l-hydroxy-2 _f 4-di-tert. -butvlxantftion

A mixture of 27.6 parts of 2-hydroxy-benzene-1-carboxylic acid, 44.4 parts of 4,6-di-tert-butyl-1,3-dihydroxybenzene (shown by alkylation of 1,3-dihydroxybenzene with tert. Butanol in Presence of catalytic amounts cone. Sulfuric acid) and 50 Parts of acetic anhydride is slowly distilled at ordinary pressure. The yellow distillate is mixed with cone. Strong alkaline sodium hydroxide solution and after two hours the soluble sodium salt of 1-Hydroxy-2,4-di-tert-butyl-xanthore, unsoaded. This is in Glacial acetic acid dissolved in hot water. On cooling, 12 parts of l-hydroxy-2,4-di-tert-butylxanthone crystallize out. M.p. 165 ° (non-rigid)

The elemental analysis of this compound gave the following result!

Ci calc. 77,75Ji Hi calc. 7,450 found 77,780 found 7.430

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U94080

l ^ Hvdroxv-3- (8-hvdroxyäthoxv ^ -xanthon

11.4 parts of 1,3-M. Hydroxyxanthone (prepared according to Orover, J. Chem. Soc. 1955, 3982) are dissolved in 100 parts in sodium hydroxide solution and, after addition of 5 parts of ß-chloroethanol, for two hours on a water bath at 90 ° -100 ° heated. After cooling, the sodium salt of l-hydroxy-3- (ß-hydroxyethoxy) -xanthones is filtered off with suction, washed with dilute sodium hydroxide solution and water and dissolved in hot dilute acetic acid.On cooling, 10 parts of l-hydroxy-3- (ß-hydroxyethoxy crystallize ) -xanthone from. M.p. 170 ° (uncorrected)

The elemental analysis gave the following result:

Ci calc. 66.18 * Ht calc. 4.44 * found. 66.01 * found. 4.46 *

The l-hydroxy-3,6-bis- (ß «hydroxyethoxy) -xanthone is carried out analogously Implementation of 1,3,6-trihydroxyxanthone with β-chloroethanol posed. M.p. 230 °

Ct ber.61.44 * Ht ber.4.85 * found 61.59 * found. 4.82 *

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Example 2

Commercial chlorinated polyester resin based on 1,4,5,6,7,7-hexachlorobicyclo- (2,2,1) -5-hepten-2,3-dicarboxylic acid, ("Hetron" ^ Hooker Electrochemical Co., Niagara Falls, U.S.A.) with the addition of $ 0.5 one of the following table specified light stabilizer between 2 glass plates - as described in Example 1 - polymerized to 2 mm thick plates, cut into test specimens and exposed in the fadeometer. The transparency values of the test items are compiled in Table 2

Table 2

• • Light stabilizers Transmissi
for light ν
unexposed on in $
at 500 m / t
exposed
500 hours Protection in
$ after
500 hours 1-hydroxyxanthone 88.0 86.8 97 1 l-hydroxy-4-chloro-xanthone 87.2 85.0 94 ] ■ l-hydroxy-5-methyl-xanthone 87.0 75.0 69 1-hydroxy-3-methoxy-xanthone 88.0 84.8 91 Without, (blind test) 89.5 51.0 0

As can be seen from Table 2, according to the invention light stabilizers used provide very good protection for chlorine-containing flame-retardant polymers.

Similar protection is obtained by incorporating a light stabilizer listed in Table II into flame-retardant polyester resins based on chlorinated phthalic acid.

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ORIGINAL INSPECTED

- ^u - * ■ Ί 4940.80

■ jjeispl.el.-3

It provides Celluloseacetatflime ago _ä by 15.0 parts per purchasable Cellulosed. 1/2 acetate (Lonza, Weil a / Rhein, Germany) dissolves 0.3 part of one of the light stabilizers given in Table 1 and 2.0 parts of dibutylphthalate in 82.7 parts of acetone and draws a film therefrom on a glass substrate. The films, dried first at room temperature and then at 60 °, are 0.04 mm thick. Samples of it are in the fadeometer 1000 _; Hours exposed and checked for brittleness by folding. It was found here that cellulose acetate films which contain a light stabilizer given in Table 1 can still be folded easily, while those films which do not contain such a light stabilizer splinter.

All® Films That One in Table; 1 specified light stabilizer containj are practically UV-impermeable, while light protection agent-free » Films UV light from mohr old> 300 mu practical not absorbable.

To ensure the light resistance of the light protection agents against UV light To test yourself, cellulose-2.1 / 2-acetate films are made with 0.03 parts of light stabilizer instead of 0.3 parts of the im Example given recipe prepared. These films show easily measurable transmission values of 5-95 ^ 5 at 350 bia 3Θ0 nsu. at Ubarmttesigtr reduction in concentration as in this example The use of only 0.03 parts instead of 0.3 parts of light stabilizer results in the concentration dependency known from dyeing Lightfastness in appearance.

In spite of this, those used according to the invention turned out to be Light stabilizers as lightfast and therefore suitable for achieving permanent absorption and thus protective effect, as shown below Table 3 shows.

_copy 909816/0731 ORIGfNAL INSPECTED

Table III

Integral transmission for UV light from 350 to 380 mji, determined by fluorescence excitation measurements ₀

No. Light stabilizers Integrals T
unexposed egg ransmission in %
exposed 500 hours 1 1-hydroxyxanthone 38 62 · 2 l-hydroxy-4-chloro-xanthone 42 51 3. 1-Hydroxy-3> 7-dimethyl-xanthone 43 50 4th 1-Hydroxy-2,4-d'i-tert-butyl-xanthone 60 62 5 l-hydroxy-5-methyl-xanthone 37 51 6th 1-hydroxy-7-methyl-xanthone 38 "53" 7th 1 _r 3-dihydroxyxanthone 48 59 θ 1-Hydroxy ^ -methyl-xanthone 46 57 9 1-Hydroxy-3-πΐθ thoxy-xanthone 53 '67 10 l-hydroxy-3- (ß-hydroxyethoxy) -
xanthone 53 66 11 1 f 3) 6-trihydric oxy-XEUithon 57 ' 71 Cf
Γ 12th 1,6-dihydroxy-xanthone 38 58 CX.
CX 13th 1-hydroxy-3 »6-dimethoxy-xanthone 57. 69 GC 14th l-hydroxy-3 »6-di- (ß-hydroxyethoxy) -
xanthone 58 12th 15th Without (Blindvörsuoh) 93 95

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Ί494080

As can be seen from the table above, the absorption effect of the light stabilizers indicated in the table remains still largely preserved even after 500 hours of exposure in the fadeometer - (in the blind test it is practically at all no absorption present).

A similar improvement in light fastness is obtained if, instead of pure cellulose acetate, a cellulose acetobutyrate (37 ^ butyrate, 12 $ acetate) is used to produce the films.
Example 4

A bleached maple veneer was varnished with nitrocellulose varnish of the following composition:

Paint 1 Paint 2 Paint 3 Paint 4
(Blind test Gollodium wool 150 150 150 150 Alkyd resin 1
(Alkydal RD 18 R Bayer, Lever
kusen, Germany) 150 150 150 150 Alkyd resin 2
(Lacquer resin M 86 R Ciba, Basel,
Switzerland) 100 100 100 100 Dioctyl phthalate 50 50 50 50 Ethyl acetate 75 75 75 75 Methyl ethyl ketone 75 75 75 75 toluene 150 150 150 150 1-hydroxyxanthone - 22 ' - - l-hydroxy-4-chloroxanthone 22nd - - - 1-hydroxy-3-octyloxyxanthone - - 22nd -

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ORIGINAL INSPECTED

After the varnish has dried, the wood samples are three weeks exposed in daylight. The three test specimens that were coated with varnish 1, 2 and 3 show up after this exposure time the unexposed areas only a barely noticeable change, while the test specimen coated with varnish 4 a shows severe browning.

Example 5

There were 2 polystyrene plates A and B, each 2 mm thick made of polystyrene by injection molding. Plate B contains 0.1 # l-hydroxy-2,4-di-tert-butyl-xanthone. Plate A is completely colorless, panel B is slightly yellowish. This is followed by paper dyed with malachite green with plates A and B. covered and exposed for 20 hours in the padeometer. After this time, the area of paper covered by plate A is complete bleached out, while the area covered with plate B is almost the same as that of the unexposed paper in terms of its color intensity. A similar protective effect as l-hydroxy-2,4-di-tert. butylxanthone show l ~ hydroxy-3 ~ (ß-hydroxyethoxy) -xanthone, l-hydroxy-3-methoxyxanthone, l-hydroxy-4-methyl ~ 6-chlorxanthone, l-Hydroxy ^ -chlor-ö-methoxyxanthone, l-Hydroxy-r2,4-dichlorxanthone, l-hydroxy-4,6-dichlorxanthone, 1-hydroxy-O-chlorxanthone, 1-hydroxy-4-bromoxanthone, l-Hydroxy ^ -methyl-o-bromoxanthone, l-hydroxy-3-methoxy-6-bromoxanthone, l-hydroxy-3,6-dimethylxanthone, 1-hydroxy-2,4-dimethyl-xanthone, l-hydroxy-3-methoxy-Y-octylxanthone, l-hydroxy-3-methoxy-7-cyclohexylxanthone, l-hydroxy-3,5,7-1 trimethylxanthone and l-hydroxy-3,5-dimethylxanthone when they are dem

90981 6/0731 ORIGINAL INSPECTED

Polystyrene can be incorporated in a concentration of O ₉ I ^.

Example 6

Methyl methacrylate is mixed with 0.05 $ lauroyl peroxide and 0.1 # one of the 1-hydroxyxanthone compounds below is added and polymerized between two glass plates to form plates 3 mm thick. The following polymethyl methacrylate plates were produced in this way:

Plate 1 made of polymethyl methacrylate and 0.1 # l-hydroxy-5-methylxanthone μ 2 ^{M n} "" 1,3-dihydroxyxanthone

"3" ·· "" l-hydroxy-4-methylxanthone

"4" "" "1-hydroxy-3-methoxy-

xanthone

¹¹ 5 """" 1,6-dihydroxyxanthone

with 6 "" "" l-hydroxy-3,7-dimethyl-

xanthone

¹¹ 7 ⁿ "without light protection agent (blind

attempt).

Bleached birch wood foaming panels are each supplied with one of the above polymethyl methacrylate plates No. 1-7 covered and so exposed to daylight for three weeks. After that time is the Fournier plate covered with plate 7 is heavily browned, while the Fouraier plates each covered with one of the plates 1-6 show only a barely perceptible darkening.

Example ?

Paper pulp based on bleached cellulose is 10 # (based on the dry content of the paper pulp)

909816/073 1

aqueous finely dispersed dough of pigment (I) 4-chloro-2-nitro-l-aminobenzene -> Aoetoacetic acid (2'-chlorophenyl) amide (yellow) and 50 # titanium dioxide by brief grinding mixed up "

The pigment is fixed by adding 5 ^ aluminum sulfate (based on the dry content of the paper pulp) and subsequent neutralization with sodium aluminate to a pH of 7. Dry paper sheets are made from this paper pulp in the usual way, soaked with melamine-formaldehyde resin (Ciba 282 U), left to stand for 6 hours and used as cover sheets when pressing laminated papers (1 hour at 160 ° and 250 atm). Exactly the same paper laminates with cover sheets, the pigment (II) 2 ₉ 5-dichloro-1-aminobenzene - ^ ß-hydroxynaphthalene-3-carboxylic acid phenylamide (red) or (III) 3 ₉ 3'-Diohlor-benzidin - ^ l-phenyl = 3 ~ methyl-5-pyrazolone (orange) or (IV) polychlorocopper phthalocyanine (bluish green).

By covering these pigmented laminated papers with the 1-hydroxyxanthone compounds-containing polystyrene plates of Example 5 and the polymethyl methacrylic plates of Example 6, the fadeometer exposure occurring after 150 hours of fadeometer exposure in the case of pigment (I), (II) and (III) or change in color of bluish green to gray-blue in the case of pigment (IV) prevented or at least greatly reduced, while light stabilizer-free polystyrene

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ORIGINAL INSPECTED

plates or polymethylmetaorylate plates practically none Convey protection

Example 8

Polyvinyl butyral films about 0.4 mm thick are produced by adding 69 parts of a polyvinyl butyral resin, 31 Parts of triethylene glycol dihexoate and 0.2 parts of one in the table cited light stabilizer calendered. These films will pressed between two glass plates in the heat and the three-layer safety glasses obtained exposed in the fadeometer « After 500 hours of exposure, the plates which contain a light stabilizer given in Table 1 show none noticeable yellowing and remain practically impermeable to UV rays. Comparative samples that do not have such a light stabilizer contain ^ show strong yellowing.

Example 9

0.5 parts of a light stabilizer given in Table 1 are finely pulverized and intimately mixed with 100 parts of nylon 6 granules in a mixing drum. The mixture is blown in the usual way through a hollow nozzle on the extruder. Those protected with the UV absorbers Films remain flexible when exposed in the fadeometer, while unprotected films become brittle with the same exposure time.

Example 10 ,

100 parts of commercially available granules of polyglycol terephthalate are with a benzene solution, the 0.2 parts (based on the polyester) of a light protection given in Table 1

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ORIGINAL UHSPECTH * '? ^^ O

contains medium, sprayed, the solvent evaporated in vacuo and the sharp dried chips on the extruder processed into films using the blow molding process with a hollow nozzle. Samples of it show after 500 hours of exposure in the fadeometer no noticeable change and are practical for UV rays impermeable and for packaging light-sensitive food suitable"

Example 11

100 parts of high-pressure polyethylene are intimately mixed with 0.25 parts of 1-hydroxy-ß-cyclohexyloxy-xanthone in a mixing drum mixed and blow this mixture on the extruder to form a film about 0.06 mm thick. A sample of it will come with a Comparison sample without light stabilizer weathered for three summer months · After this time, the comparison sample without Light stabilizers only have a very low elongation, while the film protected with UV absorber in relation to mechanical properties remained practically unchanged

Films made of low-pressure polyethylene or polypropylene can be produced in the same way by adding 0.3 ^ l ~ hydroxy-3-cyclohexyloxy-xanthone or l-hydroxy-3-octyloxy-xanthone or l-hydroxy-3-deoyloxy-xanthone are stabilized,

Example 12

From a mixture of 67 parts of polyvinyl chloride (powdery), 33 parts of dioctyl phthalate and part of one of the

909816/0731 ORIGINAL

Light stabilizers from Table 1 are produced on a roller mill at 150 ° pollen. Samples of these films are made exposed in the padeometer for 720 hours. After this time, the test specimens containing light stabilizers are completely unchanged, or at most show individual brown dots, while the control sample without light stabilizer is very heavily browned and can no longer be folded without breaking.

909816/07 3.1
ORiQ (NAL INSPECTED

Claims (2)

Claims 1 «, use of 1-hydroxyxanthone compounds as Sunscreens 2. Use of a 1-hydroxyxanthone compound _; the aljatic groups, halogen, and in the 3- and 6-position also contain hydroxyl and ether groups as light stabilizers 3 _β Use of a 1-hydroxyxanthone compound which contains a hydroxyl or an ether group in the 3-position and can also contain lower alkyl groups or halogen, as a light stabilizer. 9098 16/0731