JPH04500698A - Radiation-curable binder system containing α-substituted sulfonyl compounds as photoactivators - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] α sulfonyl A pa binder system The present invention relates to a radiation-curable compound containing certain α-substituted sulfonyl compounds as a photoactive agent. The zero binder system (system) relating to the adhesive binder system is The activator is a photoactivator for free radical generation and/or a radioactivatable latent acid catalyst. are based on free radical and/or acid-curing components that act as .

The majority of binders in paint and coating technology require crosslinking and therefore curing by polycondensation. Therefore, zero-polycondensable basic materials based on thermosetting materials are usually It is a minoplastic resin, and its heat curing is achieved by acids, especially organic sulfonic acids. A typical frequently used acid catalyst that acts as a catalyst is para-toluenesulfonic acid ( PTS), but acid-curing systems have a shelf life once reacted with an acid catalyst. It has the disadvantage that it has a limited amount of water and gels if it is not treated in a short period of time. Amine salts or sulfonate in a blocked form such as the oxime ester of hydroxamic acid. In the case of a carbonic acid catalyst, storage stability is improved. Catalytic activation is achieved by heating to high temperatures. Acids with properties are released from the blocked product. However, with this method, Curing systems that do this require additional energy and time. Heat curing is generally very It is time consuming, which is a disadvantage in industrial production.

Apart from thermal curing methods, photochemical curing has also become important in paint and coating technology. Ta. In this method, the conversion of radiant energy requires a special method containing a photoactivator or photoinitiator. A radiation-curable composition is used. The characteristic of curing by radiation is that the reaction rate is particularly high. The main advantage is that it uses less energy. The most practically important photopolymerization reaction is ethylene. This is a polyaddition reaction caused by free radicals on a reactive double bond. Therefore the corresponding radiation The curing system consists of radically polymerizable or crosslinkable ethylenic double bonds and free radicals. The production will be based on materials containing photoinitiators.

Acid-catalyzed thermal curing systems are also photochemically active instead of conventional thermal acid catalysts. In principle, the use of latent acid catalysts that can be used for radiation curing I can do it. The acid that acts as a catalyst for the actual curing requires additional input of thermal energy. however, it must be possible to emit it from such sources by the action of radiation over a period of time. Halo- or sulfonyloxyacetophenone-type compounds used for this purpose has corrosion, yellowing of the cured film, and other drawbacks. Furthermore, film stability Otherwise, compatibility problems arise.

Alleviates the known drawbacks of acid-catalyzed thermosetting systems and allows photochemical Newer efforts are being made to exploit the benefits of activation in 6 For example, in European Patent No. 192.967, photochemically activatable latent acid catalysts Sulfonyl derivatives of aromatic and aliphatic ketones that can be used as vehicles, especially α-sulfonyl derivatives. Nylacetophenone compounds are disclosed. Compared to known ultraviolet acid catalysts , etc., have particular effects on the shelf life of cured films and binder systems. Regarding, the applied properties resulting from this are more effective and inder and radical Free radical generation for hybrid binder systems based on curable or acid-curable components It can be used as a photoinitiator.

However, the compound described in European Patent No. 192.967 has a mild reaction. The disadvantage is that it is only a small amount of information. For a given curing result, a fairly high emission radiation output and/or long irradiation times are required.

Furthermore, the disadvantages of these compounds are that their synthesis costs are quite high and that they require toxic raw materials. The use of solvents produces toxic by-products. Therefore, its production on an industrial scale production and use are problematic from an economic standpoint and from today's environmental and industrial safety requirements. .

The object of the present invention is therefore to use it as a photoinitiator for the generation of free radicals as well as to Radiation-curable binder systems based on radically and/or acid-curable components Other compounds that can be used as potential radiation-activatable acid catalysts in systems This is a confirmation of the compound.

Preferred compounds are more reactive than conventionally used compounds under comparable conditions At the same time, it should be as easy and easily available as possible.

We have discovered that certain α-substituted sulfonyl compounds meet these requirements well. I saw it.

It is a compound of formula ■.

In the formula, X is OR' or NR'R', and R1 is H%R, R-0, R J%R-COlR-COO, R”NGO5R3 is H%R, R’ is H%R, -CH R'-5Ox-R'', R is alkyl, cycloalkyl or aryl, respectively 0 or less carbon atoms, and each is unsubstituted or OH, halogen, cyano, nitro , alkyl, alkoxy, alkylthio, monoalkylamino, or bisa lucylamino, alkanoyl, alkanoyloxy, alkanoylamide, alkyl mole with koxycarbonyl, alkylaminocarbonyl or aryloxy group. Unsubstituted or polysubstituted, each substituent having 6 or less carbon atoms .

The compound of formula I is first freed by irradiation with ultraviolet light having a wavelength of 200 to 450 m. -radicals and then, depending on the reaction environment, acidic decay products. Raji Use as a photoactivator in binder systems based on cal- and/or acid-curing components. When used, this compound can be compared with conventional compounds, especially those known from European Patent No. 1'32.967. shows surprisingly higher reactivity than sulfonylacetophenone compounds. .

At the same time, the present invention also provides for free-radical and/or acid-curable components. Free radical-generating photoinitiators and/or radiation in binder systems Concerning the use of compounds of formula I as activating latent acid catalysts.

The present invention further provides free radical-generating acid catalysts and/or radiation activated latent catalysts. free radicals containing an effective amount of at least one compound of formula I as a conventional acid catalyst; Concerning radiation-curable binder systems based on cal- and/or acid-curable components .

Furthermore, the present invention provides an effective amount of at least one or more compounds of formula 1 in a binder system. curing is by UV irradiation with a wavelength of 200 to 450 r+m or by radiation. Hardening with free radicals and/or acids carried out by a combination of radiation and heating. The present invention relates to a method for curing binder systems based on the components to be cured.

The present invention also ultimately relates to a method for producing radiation-cured coatings on substrates, with formula 1 Curing with free radicals and/or acids containing an effective amount of one or more compounds A binder system based on the ingredients is applied to the substrate, and the curing reaction takes place at a wavelength of 200. This can be done by irradiation with ultraviolet light at 450°C, or by a combination of irradiation and heating.

The α-substituted sulfonyl derivative of formula 1 having the above meaning is originally a known compound of formula 1. In 1, the substituent X at the α-position of the sulfonyl group is a hydroxyl group or an amino group. , these may themselves be substituted; after all, Ia, Ib, Ic arrive at the dependent structure of the dependent expression.

Compounds of the dependent formula ra are preferred because of their structural simplicity and especially economic availability. It's something new. However, from the point of view of the present invention, compounds of the dependent formulas Ib and Ic are also equally effective.

Compounds of formula 1 and more preferred compounds of formulas 1a to Ic are present in the β-position of the sulfonyl group. It has a carbonyl group.

Particular preference is given to the corresponding compounds represented by the subformula Id.

The following compounds are representative examples of formulas I and ■δ to Id.

Phenyl-sulfonylu-methanol (2) α3 call → 2-CH2-0■ p-Tolylsulfonylumethanol o-Tolylsulfonylumethanol (4) CH3o@so□-cm2-onp-methoxyphenyl-sulfonyl -Methanol (5) (IOSO□-CH2-OH p-chlorophenyl-sulfonylu-methanol (6) O□N0802-α2 p-nitrophenyl-sulfonylu methanol β-naphthyl-sulfonylu Methanol 1-(phenyl-sulfonyl)ethanol 1-(p-) lyrusul 1-(p-tolyl-sulfonyl)butanol (m-ni) trophenyl)(p-tolylsulfonyl)methanol (p-nitrophenyl) (p-tolylsulfonyl)methanol Benzoyl (p-tolylsulfonyl)methanol (m-nitrobenzoyl) = (phenylsulfonyl)methanol Benzoyl (p-methoxyphenyl-sulfonyl)methanol methanol) Benzoyl (methylsulfonyl) methanol benzoyl (propylsulfony) methanol)benzoyl(dimethylamino-sulfonyl)methanol Benzoyl-ethoxy(p-tolylsulfonyl)pivaloyl(p-tolylsulfonyl) methanol (cyclohexyl-carbonyl)-(p-tolylsulfonyl) Neil) methanol di[(p-tolylsulfonyl)-(hydroxymethyl)1benzene (25) ()WIT-a(2-so□%oi3N-(p-tolylsulfonyl -methyl)-aniline phosphorus di(p-tolylsulfonylmethyl)aminemethyldi(p-tolylsulfonylmethyl)amine methyl)amine Ethyludi(p-tolylsulfonylmethyl)amine Benzoyl (phenylamino) (p4 lyrusulfonyl) methane (33) cH3-co4so□-cm2-oHp-acetylamino-N-(F (phenyl-sulfonylu-methyl)aniline N-methyl-N-(phenylsulfonylumethyl)-aniline (p-tolylsulfonyl)-methane Particularly preferred compounds are benzoyl(p-tolylsulfonyl)methanol, ( m-nitrobenzoyl)(phenyl-sulfonyl)methanol and benzoyl (p-methoxyphenyl-sulfonyl)-methanol, especially benzoyl (p-methoxyphenyl-sulfonyl)-methanol, -tolylsulfonyl)methanol.

Formally, compounds of formula 1 in which X is an OH- group are sulfur compounds according to the reaction format of the following formula. It is considered to be an addition product of phosphoric acid to an aldehyde.

In fact, all of these compounds can be easily obtained in excellent yields using this reaction format. Ru. For the corresponding amino compounds, this reaction can be carried out in the presence of amines or subsequently Regarding the synthesis method of the compound of formula 0 which can also be made by substitution reaction using Actual information can be found, for example, below.

(1) E. V. Meyer.

J, Prakt, Chew, 53. 167 (1901) (2) E, P, Koh ler, M., Reimer, J., Amer.

Che+++, Soc, 31. 163 (1904) (3))! , Brede rec, E, Bffider.

Chesm, Bar, 87, 128 (1954) (4) H, Brede rec, E, B11der.

Cheap, Ber, 87, 784 (1954) (5) E, B11er,) 1. D. Hermann.

(6), 5ch.

Che I! 1. Ber, 99, 48 (1966) (7) K, 5ch ank.

Liebigs Ann, Che+o, υ6, 8? (1968) Many of Equation 1 The properties of the compounds are shown in the references.

According to the invention, the compounds of formula I are very suitable as radioactive agents for use in binder systems. Can be used to advantage. A special advantage of these compounds is that they are free from the effects of radiation. - Radicals are not only released, but also acidic components undergo radiation-induced decomposition. The point is that a decomposition product is produced, which can act as an acid catalyst. This acidic Since component decomposition is further induced by heating, this reaction is further promoted by the action of heat. It is also possible to allow this reaction to proceed, or to cause only this reaction to occur.

In conjunction with these multifunctional properties, the compounds of formula I are characterized by their ability to be cured by free radicals. As a binder-based free radical-generating photoinitiator based on Binder systems based on acid-curing components, as well as mixed systems, i.e. free-radical hardening Contains acid-curable and acid-curable components side by side. so-called hybrid hybrid Equally used as a radiation-activatable latent acid catalyst in type binder systems It is possible.

According to the invention, compounds of formula 1 can be used as photoactivators in such binder systems. When using the compound, simply mix it with these binder compositions and add the necessary You can heat it slightly or add a small amount of solvent to promote uniformity of distribution. For current applications and processing methods, the compound of formula 1 is ．． If the content is 1 to 20%, it has sufficient activity.

Its preferred amount is 1 to 10% by weight, based on the total weight of the binder system. 2% is particularly preferred and economical.

The photochemical activation of compounds of formula 1 varies from about 20 to 20, depending on the nature of substituents R1 and R8. Compounds of formula I achieved by irradiation with ultraviolet radiation at a wavelength of 450 nm, in particular Substituents RI and R zero are phenyl groups or lower substituted phenyl groups, In particular, the compounds of Valid within a range. If necessary or desirable, a narrow UV-sensitive region can be used. In some cases, known co-sensitizers that absorb at longer wavelengths, such as aromatic ketones, are added. Sensitivity is increased by

Photoinitiators and/or radiation with which the compounds of formula 1 of the invention generate free radicals free radicals, which can be used as latent acid catalysts that can be activated by Radiation-curing binder systems based on components that cure with and/or acids are themselves known. It is something.

Radiation-curable binder systems based on free-radical curing components typically at least one ethylenically unsaturated compound that photopolymerizes with radicals and a suitable A mixture of other customary additives. Compounds polymerized by free radicals In fact, suitable substances are those that have an olefinically unsaturated double bond. any, especially monomers, oligomers and polymers, each of which , at least one preferably more acrylate or vinyl type unsatisfactory It has a harmonious function. There are many materials that fall under this category that are known to experts in the industry. ing. Examples of such compounds include acrylic compounds, especially aliphatic and aromatic compounds. Acrylates of monohydroxy or polyhydroxy compounds, e.g. (meth) Acrylic acid and its salts and amides, (meth)acrylonitrile, (meth)acrylic acid Alkyl lylates, hydroxyethyl (meth)acrylate, vinyl (meth) Acrylate, ethylene glycol dimethacrylate, 1,6-hexane di All (meth)acrylate, trimethylolpropane di(meth)acrylate chloride, pentaerythritol tri(meth)acrylate, or even chloride Vinyl, vinylidene chloride, styrene, divinylbenzene, N-vinylpyrrolidone and vinyl compounds such as N-vinylcarbazole. High molecular weight Rimmer and binder components include acrylated polyester, acrylate, and There are poxies, urethanes, polyamides and silicone resins. Radiation curable bi Under systems are mostly mixtures of the low molecular weight and high molecular weight unsaturated components mentioned above. .

Acid-curing binders which also represent the field of use according to the invention of compounds of the formula I As a system, any system that has at least one component that can be polycondensed using an acid catalyst. There is. Most of these are melamine or urea-based resins that can be modified in various ways. . Those skilled in the industry will be familiar with these materials, but they cannot be produced in large quantities. It is produced industrially, and its properties are modified for various uses. melamine material A typical example of this material is hexamethoxymethyl melamine. Furthermore, acid-curing binder - system may optionally contain other ingredients in varying amounts; This is common in the resin industry. Examples include alkyd, phenolic, poly esters, acrylics and polyvinyl resins or mixtures thereof. .

Compounds of formula 1 are suitable as radiation-activated catalysts, but are also particularly suitable for free radical activation. Composite binders containing acid-catalyzed reactive components capable of polycondensation as well as polymerizable components According to the invention, such compounds can be prepared purely photochemically, if It can be activated preferably by a combination of photochemical and thermal conditions. Change These compounds act equally well as free radical and acid generators. and therefore in practice simultaneously exhibit the hardening action of the various components of the mixture system. Suitable acid-curing components for the system include all of the compounds already mentioned and also examples such as Cross-links due to heat during condensation or polyaddition reactions, but cross-links due to free radicals Compounds that do not As an example.

Reaction between acid-curable melamine resin and polyurethanes or polyesters There is a synthetic resin. Suitable free radical polymerizable components include the olefins mentioned above. In practice, there is no problem with any of the compounds mentioned above having an unsaturated double bond. In the hybrid binder system, acid-curable and free-radically polymerizable components are The amount can vary over a wide range from 10 to 90% by weight.

The radiant curable binder system may be an aqueous dispersion, but the water is typically It is common to heat the material for a short period of time to remove it.

The binder system that is cured using the compound of formula 1 as a photoactivator can be used for radical polymerization alone, acid Whether curing alone or a combination of both, qualitative and quantitative compositions are widely available. This product can be varied within a wide range and, in particular, may contain other ingredients and additives. In this connection, the amount of reactive components used is preferably not less than 10% by weight, especially Other ingredients and additives used in customary amounts for specific purposes include inorganic and organic Machine pigments, paints, fillers, flow control agents, surfactants, matting agents, plasticizers, solvents, co-dispersants, other binders and resins, other photoinitiators, spectral sensitizers and Known coinitiators, other thermally or photoreactive radical initiators and cations There are acid-producing or acid-producing catalysts.

Substrates with the above binder systems, which are mainly flat objects, can be painted is performed in a known manner. If you are an expert in the industry, you should know the appropriate painting techniques and the equipment that can be used. Familiar with preparations.

The application is primarily for the production of thin films, examples of which are There is a coating of paint on all materials and substrates. Its materials are mainly paper, wood, and textiles. Important application areas include printing inks, textiles, plastics and metals. and drying or curing of screen-printed materials, the latter for example on cans, tubes and metals. It is preferably used for surface painting or decoration of manufactured stopcocks.

The binder system of the present invention containing the compound of formula 1 or the coated product using the same is free from radiation. Cured by the action of energy, especially ultraviolet light with a wavelength of 200 to 450 na+ do.

Sources of radiation include conventional high-pressure, medium-pressure or low-pressure mercury vapor lamps, e.g. Non- or tungsten lamps can be used.

For some, primarily acid-cured or hybrid binder systems, thermal energy This additional heat application, which is preferably applied at times or subsequently, to accelerate curing. Activation is carried out in the temperature range common for acid-catalyzed thermosetting systems. This temperature is 80 The temperature is from 100 to 120°C, preferably from 100 to 120°C.

A particularly advantageous property of compounds of formula 1 is that their photochemical and thermal activity can be varied and harmonized with each other by selectively selecting the It is something that can be controlled.

Curing can be accomplished continuously or discontinuously. The irradiation time depends on the nature of the method and the weight used. may vary depending on the amount and nature of the compound, the nature and concentration of the photoactivator, and the intensity of the light source. It will be done. In radiation curing of painted objects, the irradiation time is usually from several seconds to several minutes. sufficient The preferred additional heat treatment time for curing depends on the temperature and binder. Depending on the type of powder, it can take anywhere from a few minutes to several hours.

Comparable radioactivators, in particular the α-sulfonyl compounds known in EP 192.967. Compared to ruacetophenones, the compound of formula 1 has comparable application and processing conditions. The hardness of the films produced below showed an unexpected advantage of distinctly greater hardness.

Shorter irradiation times are required to obtain a given film hardness.

The above compounds reacted with known radioactive and heated acid catalysts to the buffers treated with them. It has even better storage stability than the Inder type. Also, the cured final product may have a negative impact. No influence of dust, especially no tendency towards yellowing, was observed.

The simple and unproblematic availability of the compounds of formula I and their excellent application properties make them This makes the compound particularly valuable for practical purposes.

(Example) A, I A The preparation and characterization of compounds of formula I in Table 1 below are described in the cited literature. or a similar method. All prepared compounds have correct elemental analysis The value was shown.

′　　　’　　A　31 Phenylglyoxal hydrate 7.6g (50ma+ol) and aniline 4.6 g (50 mmol) was stirred in 50 ml of THF at room temperature for 2 hours. Next, 7.8 g (50 ooaol) of toluenesulfinic acid was added, and the mixture was further heated at 16 o'clock. The separated precipitate was separated by suction filtration, washed with ether, and reconsolidated from toluene. crystallized. The obtained product was benzoyl (phenylamino) (p -)lylsulfonyl)methane 9.9g (27IDmol=54% of theoretical value) Met.

To the second bottom ℃ 1 3 65.5 60 2 1.3 96 95 8 2.3 52 11 2, 3 91.5 110 12 2.3 109-111 11613 92.5 24 128.5 30 155.5 31 131.5 35 (decomposition temperature>90) B, ・, 2% of the compound of formula I of the invention for test use (compound no. 14) and the comparative substance (EP A 2% lθ% solution of 192.967 (DTA) in n-butanol, Each was uniformly stirred and mixed into a coating system (compound binder system) containing the following:

72 parts by weight of acrylated aromatic epoxy resin CBASF Laromar EA81 ) 18 parts by weight hexanediol diacrylate 10 parts by weight hexamethoxime Chilmelamine (manufactured by Dyne Cyanamid Cymel ■303) Paint prepared above The sample was coated on a glass plate (10cm x 10cm) to a film thickness of 80μm, and left in air at room temperature. for 10 minutes and the solvent was removed.

After aeration, the painted glass plate was placed in an ultraviolet experimental dryer (Beltron model BE22). Inside the conveyor belt speed 2.5m/min to 40cm/min (radiation time 1.5m/min) sec/l to 24 sec/m) and 10 cm under a medium pressure mercury lamp with an output of 801/cm. It was passed at a distance of .

After UV irradiation, the painted panels were cured in a laboratory drying oven at 120°C for 30 minutes. Ta. After curing and cooling, the surface condition was measured by a sensory test, and after about 20 hours of baking, the hardness The Koenig pendulum hardness (DN 53157) was measured as a measure of hardness.

The results are shown in Table 2 and Figure 1.

Table 2 (note) (a) Pendulum hardness (seconds) according to DIN 53157, measured 20 hours after curing .

(b) Surface condition immediately after thermosetting + = dry surface (+) = insufficient drying −=sticky surface It can be seen that over the entire range of cure rates using the compounds of the invention, the comparative It is possible to obtain a painted surface with significantly higher hardness than that obtained by coating with high quality paint.

In order to achieve a coating film with a predetermined pendulum hardness (for example 170 seconds), the compounds of the invention When used for activation, curing occurred at a faster rate than when using the comparison material. (e.g. a speed of 6 m/min instead of 4 ffl/min).

1jη international search report -1■-1-1-mkPcT/EP 90100927 International Search Report

Claims (6)

[Claims] 1. a photoinitiator and/or a radioactive latent acid catalyst that generates free radicals; containing an effective amount of at least one compound of formula I. Radiation based on components that are cured by radicals and/or by acids Hardenable binder type. ▲There are mathematical formulas, chemical formulas, tables, etc.▼In formula (I), X is OR3 or NR 3R4, R1 is H, R, R-O, R2N, R-CO, R-COO, R2N CO, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and R2 is R, OR, NR2, R 3 is H, R, R4 is H, R, -CHR1-SO2-R2, R is alkyl, cycloalkyl or aryl, each having 10 or fewer carbon atoms, each unsubstituted; or OH, halogen, cyano, nitro, alkyl, alkoxy, alkylthio , monoalkylamino or bisalkylamino, alkanoyl, alkanoyl alkoxycarbonyl, alkanoylamide, alkoxycarbonyl, alkylaminocarbo mono- or polysubstituted with neil or aryloxy groups, respectively The number of carbon atoms in the substituent is 6 or less. 2. 0.1 to 20% by weight of the compound of formula I, preferably 1 to 10% by weight A binder system according to claim 1, characterized in that it contains. 3. Compounds of formula I can also be used as components that are cured by free radicals and/or acids. Free radical-generating photoinitiators and or Method of use as a radioactivated latent acid catalyst. 4. Adding an effective amount of at least one compound of formula I to the binder system and curing is carried out by irradiation with ultraviolet light with a wavelength of 200 to 450 nm, or free radicals and heating. / or binder-based curing methods based on components that are cured by acids. 5. 5. The method of claim 4, wherein the compound of formula I is preferably added in an amount of 0.1 to 20% by weight. is added in an amount of 1 to 10% by weight. 6. A method for producing a radiation-cured coating on a substrate, comprising: By coating the base material with an inder type and irradiating it with ultraviolet rays with a wavelength of 200 to 450 nm. , or by a combination of irradiation and heating. Method.