CA2132855A1 - Addition products, radiation-curable surface coating compositions based on the addition products and their use for woodcoating and papercoating - Google Patents

Abstract

Abstract Addition products, radiation-curable surface coating compositions based on the addition products and their use for woodcoating and papercoating The present invention relates to addition products of A) oligomers having at least two acrylic ester and/or methacrylic ester groups per molecule and B) diamines having a primary and a tertiary amino group, the ratio of primary amino groups of B) to the (meth)acrylic double bonds of A) being 0.01:1 to 0.2:1, preferably 0.03:1 to 0.1:1.
The invention also relates to processes for the preparation of the addition products, to radiation-curable surface coating compositions based on the addition products and to the use of the surface coating compositions for woodcoating and papercoating.

Description

- ` ` flLE. F~N THIS Ah~c~FJrD
TEXT TRANSLATION
1328~
April 9, 1992/fe BASF Lack- I Farb-n Aktleng~ chaft, M~t-r Add~tiou product~, radiation-curable ~urfac- coat~ng compo~tion~ ba~ed on the addition product~ and th-ir u~e for woodcoatlng and papercoatlng The pre~ent inventlon relates to addition products of A) oligomerR having at least two acrylic ester and/or methacrylic ester groups per molecule and B) polyamines Furthermore, the present invention relates to radiation-curable surface coating compositions ba~ed on the addition products and to the u~e of the radiation-curable surface coating compositions for the coating of wood, woodbase materials and paper Curing of compositions based on acrylic ester~
by radiation, in particular W radiation, is known However, the problem with this method is that the presence of air interferes with surface-hardening Photopolymerizable surface costing compositions containing amines as reducing agent~ or chain-transferring compound~ are disclosed in German Patent Specification 2,625,538 The disadvantage of using such a free amine is that it can act as plasticizer and leads to an undesirable deposit on the ~urface and to ~1328~ :
. .

odor nuisance.
By incorporating the amino group in a molecule which atditionally contains polymerizable groups it i9 possible, on curing-, to obtain an amine which is present as copolymerized unit and doe~ not show the abovementioned disadvantages. A known method of incorporation is the addition of ~m; nes to molecules - which are high in double bonds, which addition proceeds analogously to a Michael addition and i8 described, for example, in P. Moller, ~ouben-Weyl, Vol. 11/1 l1957), pp. 277-280. US Patent Specification 2,759,913 teaches the addition reaction of amines with activated, olefinically unsaturated compounds, such as acrylates, in equimolar amounts, which results in complete conversion of the activated ethylenic double bonds.
Systematic investigations on the addition reaction of amino alcohol~ with acrylates have been carried out by N. Ogata and T. A~ahara, Bull. Chem. Soc. Jap. 39, pages 1486-1490, 1966.
German Patent Specification 2,346,424 describes the preparation of radiation-curable compositions, starting from acrylic esters of polyhydric alcohols and secondary, aliphatic monofunctional amines. These com-positions have the disadvantage of reduced shelf life.
Moreover, the addition reaction of a secondary ~mine leads to a reduction in acrylic ester functionality of the molecule and thus also to a reduction in crosslinking possibilities for the radiation-induced polymerization.
" ' ' ~,-., ':

2 1 3 2 8 ~ ~ ~

Addition products of esters of acrylic or methacrylic acid and polyhydric alcohol~ with pr;~ry monoamines, in which the molar ratio of monoamine to (meth)acrylic double -bond of the e ter i8 0.05:1 to 0.4:1, are disclosed in EP-A-280,222.
The addition products according to EP-A-280,222 are used in radiation-curable compositions which harden in air. However, the shelf life of the products disclosed in EP-A-280,222 i~ insufficient. Thus, upon storage ~f ., - ., ~
the addition products, a significant increase in vi~cosity is observed. Furthermore, addition products of tetrahydric polyols with primary monoamines give ri~e to compatibility problems. Product~ of this type have a cloudy or milky-white appearance. A further ;
disadvantage of the amine-modified compositions des-cribed in the European application is that a relatively large amount of monoamine is necessary for ensuring that the nitrogen contents in the addition products obtained are sufficiently high for, for example, systems initiated by benzophenone. Sufficiently high nitrogen contents are necessary to ensure that in practice the photopolymerization is sufficient and goes to completion at the customary radiation dosage. ;~
EP-A-2,457 describes plastics for molded articles, the plastics curing under elevated temperatures. The plastics are Michael addition product~ of acrylic e~ter monomers with amine~ having an amine hydrogen functionality of at least 3. The components are reacted at an eguivalent acrylate/ amine ~ ~
', ~'.:

21328~
. . .

hydrogen ratio of 0.5 to 2Ø
Radiation-~iurable solvent-free composition~
based on polyacrylates and mono-, di- or polyamine~ are disclosed in US Patent Specifications Nos. 4,547,562 and 4,675,374. Species having more than one primary amino group are mentioned as suitable di- and poly-amines. The use of these polyamines gives highly crosslinked surface coating compositions of higher molecular weight and thus higher viscosity which, without addition of reac ive thinners and solvents, have an application vicGosity which is too high or even lead to solid products.
Finally, US Patent Specification 4,045,416 and US Patent Specification 3,845,056 relate to radiation-curable surface coating compositions based onaminoacrylates which are obtained by reaction of polyacrylates with amines having at least one amine hydrogen. Primary and ~econdary monoamines and poly-amines are mentioned a~ suitable amines. The polyamine components mentioned in the US Patents are polyamine~
having more than one primary amino group, polyamines having exclusively secondary amino groups or polyamines having secondary and tertiary amino group~. When polyamines having more than one primary ~m; no group are ;~
used, tha addition products obtained are inhomogeneous and have a short shelf life, while the use of polyamines having exclusively secondary amino groups, such as, for example, piperazine, leads to inhomogeneous mixture~ due to insufficient reactivities --~ ~ ~
.,., ~,~ ..~.
, '. .

21328.~

or incompatibilities. The use of polyamines having secondary and tertiary amino groups only results in a reduction of the acrylic or methacrylic ester functionality of the molecule.
Accordingly, the object of the present invention was to eliminate the disadvantage~ described above, i.e. to provide radiation-curable binders which have a sufficiently long shelf life and a clear appearance, i.e. are homogeneous, even when tetrafunctional ~meth)acrylic esters are used as precursors. The binders should be radiation-curable without using external synergists, for example amines.
The binders according to the invention should be low-viscosity oligomers having comparatively good radiation-curability and comparatively good resulting film properties, in particular hardness. The binters should have a low viscosity, 80 that the use of reactive thinners and organic solvents can be omitted.
The object of the present invention is achieved by addition products of A) oligomers having at least two acrylic ester and/or methacrylic ester groups per molecule and B) polyamines, wherein polyamines B) are diamines having a primary and a tertiary amino group and the ratio of primary amino groups of B) to (meth)acrylic double bonds of A) is 0.01:1 to 0.2:1, preferably 0.03:1 to 0.1:1.
Examples of suitable acrylic and methacrylic esters (A) are esters of acrylic acid or methacrylic ~1~28~

acid with dihydric aliphatic alcohols, such as ethylene glycol, 1,2- and 1,3-propylene glycol, 1,4-butanediol, 1,2-pentanediol, neopentylglycol, 1,6-hexanediol, 2-methyl-1,5-pentanediol, 2~ethyl-1,4-butanediol, di-methylolcyclohexane and diethylene glycol, with tri-hydric alcohols, such as glycerol, trimethylolethane, trimethylolpropane and trimethylolbutane, with tetra-hydric alcohols, such as pentaerythritol, and with alcohols containing more than 4 hydroxyl group~, ~uch as di(trimethylolpropane), di(pentaerythritol) and sorbitol .
Also suitable are cycloaliphatic alcohols, such as cyclohexanols and 1,4-bis~hydroxymethyl)cyclohexane, araliphatic alcohols, such as 1,3-xylylenediol, and phenols, such as 2,2-bis(4-hydroxyphenyl)propane (bisphenol A).
Esters of acrylic acid and/or methacrylic acid with tri- or tetrahydric alcohols are preferably used as component A).
Before being esterified with acrylic acid or methacrylic acid, the polyhydric alcohols listed above can have been converted into ether alcohols of higher molecular weight by alkoxylation with, for example, ethylene oxide or propylene oxide. This reaults in polyether acrylates or polyether methacrylate~. Poly-ether (meth)acrylates of this type are particularly preferably used in the addition products according to the invention as component (A).
The hydroxyl-containing polyethers which are - 21328.~ -e~terified with acrylic acid and/or methacrylic acid are obtained by reaction of &i- and/or polyhydric alcohols with different amounts of ethylene oxide and/or propylene oxide by well-known methods (see, for example, Houben-Weyl, Volume XIV, 2, Makromolekulare Stoffe II tMacromolecular Substances II], (1963).
Polymerization products of tetrahydrofuran or butylene oxide can al~o be u~ed.
Suitable components A) are also polyester acrylates and/or polye~ter methacrylates. The polyester (meth)acrylates are prepared by using hydroxyl-containing poiyester~ (polye~ter polyols) as the poly-hydric alcohols. These can be prepared by esterification of dicarboxylic acids with diols and triols by well-known methods (see, for example, P.J. Flory, J. Am. Chem. Soc. 58, 1877 (1936) and J.
Am. Chem. Soc. 63, 3083 (1953).
In some ca~es, it is particularly advantageous to react an epoxy resin with acrylic acid or methacrylic acid in a stoichiometric amount, relative to the epoxy functionality. Polyglycidyl ethers of bisphenol A are particularly suitable in this respect.
Before the reaction, they may also contain a few hydroxyl groups. The reaction with acrylic acid or methacrylic acid leads to furth~r hydroxyl groups. Such polyhydric acrylic esters or methacrylic esters are designated as epoxyacrylates or -methacrylates. The addition of hydroxyl-containing acrylic esters or methacrylic esters, ~uch as hydroxyethyl acrylate or - 21 3~855 hydroxybutyl acrylate, to isocyanato-containing mono-or oligomerY gives the polyurethane acrylate~ or methAcrylate~ which, like the epoxy(meth)acrylates, can be u~ed a~ e~ter component A).
The preparation of polyether acrylate~ and polyester acrylate~ i~ described, for example, in DE-A-3,836,370.
Suitable diamines having a primary and a tertiary amino group (component B)) are N,N-dialkyl-diaminoalkanes, ~uch as, for example, N,N-dimethyl-1,3-diaminopropane, which i8 obtainable by catalytic .
hydrogenation of timethylaminopropionitrile. ~he pre~
~ ....
paration of thi3 polyamine is described, for example, in ~ouben Weyl, Vol. 11/1, 1957, p. 565, in EP-A-316,761 or in P. Lappe, H. Springer and J. Weber, Chem.-Ztg. 111 (4), pp. 117-125 (1987).
Further suitable dialkylaminopropanes are N,N-diethyl-. : .., -: :: ~
1,3-diaminopropane, N,N-di-n-propyl-1,3-diaminopropane, - ~ :: : .

4-morpholinopropylam;ne, 3-(N-piperidino)propylamine, N,N-diphenyl-1,3-diaminopropane.
. .
Other 3uitable components ~) of the addition products according to the invention are: N,N-dialkyl-~ ,, .,, ;
1,2-diaminoethanes, such a~ dimethylaminoethylamine, ~;
. . .
diethylaminoethylAm;ne, N-~-aminoethylmorpholine (for ~ -preparation, see, for example, Houben Weyl, Vol. 11/1, 1957, p. 563), N,N-dialkyl-1,5-diam;nopentanes, which . :. :
can be prepared by 1,4-addition of secondary amines to 1-cyano-1,3-butadiene to give nitrile~, followed by catalytic hydrogenation (for preparation, see ~ouben ~ A ~ . . i, i .

.~ 213~8~5 Weyl, Vol. 11/1, 1957, p. 276). Examples of suitable N,N-dialky1-1,5-diaminopentane~ are dimethylamino-pentylamine, diethylaminopentylamine, 4-morpholino-pentylamine.
Particularly good results are obtained by using N,N-dimethyl-1,3-diaminopropane as d ne component B).
The ratio of A) to B) i9 selected in such a manner that the ratio of primary amino groups of B) to the acrylic or methacrylic double bonds of A) is 0.01:1 ",~-to 0.2:1. This ratio is preferably 0.03:1 to 0.1~
The addition products according to the inven-tion are liquid at room temperature. They are prepared by adding diamines B) in a Michael reaction to an acrylic ester or methacrylic ester A) or to a mixture of these esters. The amine-modified oligomers obtained still contain unreacted acrylic ester and/or methacrylic ester groups and tertiary amino groups.
The addition reaction i~ exothermic and is carried out in liquid phase at a moderate temperature in the ab~ence of a catalyst. The appropriate amount of diamine (B) i8 added to ester (A) at room temperature with stirring. The temperature rise~ to ~bout 40C.
When the reaction is complete, the evolution of heat stops, and the temperature drops. The reaction can be accelerated by increasing the temperature 80 that at 60C it will have subsided after about 12 hours. The visco~ity of the mixture obtained is then constant with time.
For reasons of reproducibility, the reaction . 2~ 3~8.~
. . .-should go as far to completion as possible, which is ~chieved at reaction temperature~ above 50C.
In general, the reaction is carried out without solvents, but it is al o possible to u~e solvents, especially in order to meter in solid amine~ ~) as a solution. After Michael addition ha~ taken place, the solvent is removed.
~ o ensure that no undesirable polymerization takes place during the addition reaction, 10 polymerization inhibitors are usually added to the ¦
reaction mixture. Suitable polymerization inhibitors include known product~, such as substituted phenQls, such as 2,6-di-tert.-butyl-p-cresol, hydroquinones, such as methylhydroquinones, and thio ethers, such as 15 thiodiglycol or phenothiazine. ;
Accordingly, the present invention also relates - :
to a proces~ for the preparation of the addition products according to the invention, which compri~es ~;-reacting e3ter component A) and diamine component B) with one another, if appropriate in an organic solvent, with the uqe of polymerization inhibitors. ;
The amine-modified addition products according to the invention obtained from components A) and B) are used a~ film-forming components in radiation-curable ~urface coating composition~. Depending on the vis-cosity of the e~ters, these radiation-curable surface coating compositions can contain, apart from the amino-modified oligomers according to the invention, further copolymerizable compounds known for being used in ~S '~L : i ' ~. ,~ .': i .; ~ : ~ s .~ ,,,,,; , 21328~
`~`

radiation-curable surface coating compositions, for example (meth)acrylic ester~, in particular methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)-acrylate, butyl (meth)acrylate, ii~opropyl (meth)-acrylate, isobutyl (meth)acrylate, pentyl (meth~acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, 3,5,S-trimethylhexyl (meth)-acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, hexadecyl (meth)acrylate, octadecyl (meth)acrylate, octadecenyl (meth)acrylate and the corresponding esters of malein, fumaric, tetrahydrophthalic, crotonic, i~o~
crotonic, vinylac0tic and itaconic acids. Preference i~
given to the use of monomer3 having more than 1 double lS bond per molecule, for example ethylene glycol diacry-late, diethylene glycol diacrylate, propylene glycol diacrylate, trimethylene glycol diacrylate, neopentyl glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-~utylene glycol diacrylate, 1,6-hexamethylene glycol diacrylate, l,10-decamethylene glycol diacry-late, trimethylolpropane triacrylate, pentaerythritol tetraacrylate and pentaerythritol triacrylate and the corresponding methacrylates. Very particular preference is given to the use of trimethylolpropane triacrylate and acrylic esters of propoxylated trimethylolpropane.
~ owever, addition of these monomeric, copoly-merizable compound~ ~often also called reactive thinner~ in general not neces~ary, ~ince the amine-modified esters according to the invention have low ~ 1328~,5 Vi8CoBity -Depending on the viscosity of the addition products according to the invention, the radiation~
curable surface coating compositions can contain water, although addition of water is in general not necegsary due to the low viYcogity of the film-forming components. The advantage of the addition products described must in particular al~o be attributed to the fact that they are dispersible in water, i.e. the use of organic solvent can be entirely omitted.
The addition products obtained from A) and B) contained in the radiation-curable surface coatins compositionY
are water-Yoluble or water-dispersible by virtue of the tertiary amino group~ contained therein. These groups can be converted to the charged group~ by reacting at least Yome of them with acids. Examples of acids which are suitable for neutralizing the basic groups are lactic acid, acetic acid, formic acid and phosphoric acid.
The radiation-curable surface coating compo-sitionY additionally contain photoinitiators commonly used in radiation-curable surface coating compositions, for example benzophenones, benzoins or benzoin ethers.
The u8e of synergists can be omitted, ~ince the esters contained in the surface coating compositions are ne-modified and thus exhibit a synergistic action.
The radiation-curable compositions according to the invention can contain, apart from the m;ne-modified reaction products obtained from esterY A) and r ~

~` 21328~

diamines B), further photopolymerizable binders, which may also be amine-modified. Examples which are suitable as such further ~mine-modified binders are the radiation-curable binder~ di~closed in EP-A-280,222 and in US Patent Specifications Nos. 4,045,416, 4,547,562 and 4,675,374. Suitable non-amine-modifiet further binder~ are the polyether acrylate~, polyether methacrylates, polyester acrylates, polyester methacrylates, urethane acrylate3, urethane methacrylates, epoxy acrylates and epoxy methacrylates described above as example for component A).
If desired, the radiation-curable surface coating compositions according to the invention contain customary auxiliaries and additives, for example extenders, such as talc, heavy spar, aluminum silicates, dolomite, antifoams, flow-improving agents and film-forming aids, for example cellulose derivatives, and flatting agents in the usual amounts.
The ~urface coaSing compo~itions can be applied to the sub~trate, preferably to wood, woodbase material~ or paper, by spray-coating, roller-coating, flow-coating, dip-coating, knife-coating, brush-coating, pouring or by Vakumat application.
Curing of the coating film~ takes place immediately after application or after evaporation of any water present by means of W or electron beams. The equipment and conditions for these curing methods are known from the literature (~ee, for example, R. ~olmes, U.V. and ~.~. Curing Formulation~ for Printing Ink~, 7~

213~855 Coatings and Paints, SITA-Technology, Academic Press, London, United Ringtom 1984, pages 79-111) and need no further description.
The surface coating compositions according to the invention are also suitable as printing inks.
The radiation-curable surface coating compo-sitions according to the invention or the amine-modified esters obtained from components A) and B) have an excellent shelf life. The amine-modified ester3 are homogeneous, have a clear appearance, good radiation curability, and the film~ obtained therefrom after radiation curing posse~s excellent properties. While having a comparable nitrogen content and comparable reactivity towards radiation, the amine-modified esters according to the invention have lower viscosity than the amine-modified esters according to ~P-A-280,222.
The films obtained are distinguished by excellent tranaparency.
Below, the invention is illustrated in more detail by way of exemplary embodiments. Parts are by weight, unless stated otherwise:
~xa~pl--To prepare ester component A), polyether acrylates are prepared from acrylic acid and tri-methylolpropane alkoxylated with propylene oxide andfrom pentaerythritol alkoxylated with ethylene oxide in the presence of acrylic acid (polyether acrylats pre-cursor). Preparation takes place in a reactor of batch size 3 to 10 kg which is equipped with stirrer, air '` - ~ ' i;': i' 'i ' ~ 32855 '`

feed, temperature sensor and oil jacket heating.
~sterification takes place at 130C with acid catalysis (0.5% of methanesulfonic acid, relative to the starting materials) using 2% of cyclohexane as entrainer and hydroquinone and hypophosphorous acid as stabilizers (0.2% by weight of hydroquinone and 0.05% by weight of hypophosphorous acid, relative to the starting materials) until an 0~ group conversion of at least 85%
is reached. Residual acrylic acid and residual entrainer are then removed in vacuo until the acid number has reached a value of s 4 mg of ROH/g and the solids content (1 h, 130C) is at least 98%.
Adduct formation with amine component B) is carried out at 60C in a nitrogen ~tmosphere using 0.1% of 2,6-di-lS tert.-butyl-p-cresol as stabilizer (polymerization inhibitor) until a viscosity is reached which remains constant over a period of 2 hours.
In this reaction, amine component ~) is metered into the initially introduced ester component A) over a period of 0.5 to 1.0 h. If piperazine is used, it is added as a powder which ~lowly dissolves. (Comparative Examples C1-2 and C2-3).
The table below lists th~ composition and properties of addition products according to the inven-tion obtained from A) and B) (~1 to E3) and those ofknown addition products obtained from A) and primary and secondary monoamines and disecondary diamine~ as comparison (Cl-C3).

328 ' ~5 - 16 ~

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~, ", o ,~ ~ .~
L~ o o~
~Q ~o ~o u~
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~ O O ~ I~ ~ ''' ~ -~, `"' ,''' '.', ~) 0 0 4 : -: :: ~
O æ 0 4 -.`~
N CU
g ~ 8 O _ ~ N ~
. :, .
~ g æ O ~
1~1 _ ~t N ~t _ ~,: `- '''':: :.`,':

~1 _ ~ -I , ' " ' `, ` ~ ~

o 5.0 0 N ~ ;

1~1 g . ` ~

~1 O ~ o ~ E ,~ o E E ~ _ ~ E o ~ Z ~ c ~ ~

o o CL o ~ o W W ~9 ~ ~ . `,`; , _ e _ 5 X L _ _ _ ~ ,~
~ O ~ o e o e ~ ~ e ~ ::
U ~ ~ L e ~,~ ~ ~ E 1~9 E ~ It E ~ E~ ,~ ~ ~, O 5 X ~ ~ L ~ L 11~ ~ SU IJ -- -- O -- `:
-- O ~ ~ 111 ~ ~
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~ r~ O Y
~ ~3 ~ ~ :
_ 3 ~ ~ ~ .: . .
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-~ ~ ? ~ 0' ~o O
C o~ C ~ t ~
l ~ 5 o ql ~ 8 ~ ~:
U ~i ~ U ~ _i o ~ U .
o ~ P o ~ P ~ o : ~: :,: .: ~ .
c ~
:
* U o C ~ `
C~l ~ C ~
~ C~ ~ ~ ,., ~1, ," ,_, o ~ ' * IJ 3 ~ o U~ UO~ ~o.
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c~ o o _~ c ~ o~8 o ~ J, ~ C ,~ ~, o a :
U ~ o~Ul O
o ~ ~ ~1 o ~ ~ -P~ c ~ P~ -u~ ~ ~:
o .~ c c 0 0 "~ ~
o . .
~1 ~
.: : :
~J O 0 C O d~ ~ ' ~ ~ ~ ~ . 3 o ~ U y O P ~ ....
" ~, ~o ~ ~
" ~ ,11~ O U ~ ' -^ ~ ~ B ~: -C o~ oo ,. ~ o~ o C o ~ o ~4., , .~. .. .
U ~ ~ _, ~ o, _, ~ ~ ,t C U o ~ . . -. ;..... .
~ ~ 3 ~ 3 ~ ~ o ~
-- ~U U C . ~ u ~ ~ ~ .J C U ;~ . .: ': .
~ ... .. ~ , C ~ o ~ o ~ .- ., 4 U~ `3 P C ~ ~0 ~ ~ P 1~
~1 U O U~ o ~S~ o ~ ~ ~ " ~ .-P ql u tO u o ~ o ~I C ~ o ~ o C o 1!1 ~ Z'~ P O 1~~ .C P ~ ~

: ;' -.:

21328~,5 ...... ..

T-~tlng of th- addttion product~
1. Pendulum damping (X8nig, [8]) of the examples and comparative examples a~ a function of relative radiation dosage A 40 ~m thick (wet film thickness) coating on gla88 i8 prepared from 91.6 parts of the addition products or precursors, 3.4 parts of a conventional flatting agent and S parts of benzophenone by drawing down. The glass plates are cured under a mercury medium-pressure lamp (80 watt/cm, distance: 20 cm) at variable ~peed~ of 10-40 m/min (relative doses ~ 1.0 -a feed of 10 m/min; relative do~e~ ~ 1.0 ~ a feed of 4 x 40 m/min; relative doses ~ 4 - 4 x 10 m/min and relative doses ~ 0.25 ^ 1 x 40 m/min). The pendulum hardnesses of the tack-free films are determined by the method of R8nig.
' " "
:.

. .... ...

2 1 3 2 8 5 ~
, . . . ~ ~

:,",~
1.1 ~111 1 1 1 1 rl I I I ;, ~
_ __ _ _ _ _ ~I a _ ~ e~ ~ ~ I ,1 ~ o ~ I o .
_ _ ~ ~ ~ _ _ _ , _ _ _ , ' ~'"''''': ~'"'' :. ' ~ ~ o r ~o el e~
_ t~ ~ ~ r _ C ~ r _ _ r ; ~ :

_ _ _ _ _ _ _ _ _ _ '~
_l ~ ~ ~o ~o u~ e~ :
_ 7c _ _ e e _ _ u ~r _ c _ u~ _ _ _ _ _ _ _ _ _ , '~
I
~1~ ~ ~
_ __ r r r _ ~ ~1 e r_ ~ _ _ _ _ _ _ _ c a ~ c c _ c _ ~ .
l 1, 1 ~1 ~ ~

X ~ P~ ~ ~

r~ 32855 2. Shelf life The shelf life of the addition products at 50C
i8 determined.
Oven ~pecimen~ ~50C): change in viscosity with 5 time (orig.) DIN 4 t8] :
, ' ~
5 day-10 day- 30 day-120 day~ Note . _ ~1 73 74 73 75 l _470 470 4~5 570 .:~

~3 123 123 125 .~.'- ,.. .. '~.
C3-1 136 lSo 170 20 day-s 2 pha~e-C3-2 49 52 54 ;
'~

' .., ' ~:

Claims (7)

Patent Claims

1. Addition products of A) oligomers having at least two acrylic ester and/or methacrylic ester groups per molecule and B) polyamines, wherein the polyamines are diamines having a primary and a tertiary amino group and the ratio of primary amino groups of B) to (meth)acrylic double bonds of A) is 0.01:1 to 0.2:1, preferably 0.03:1 to 0.1:1.

2. Addition products as claimed in claim 1, wherein esters of acrylic acid and/or methacrylic acid and tri- and/or tetrahydric alcohols are used as component A).

3. Addition products as claimed in claim 1 or 2, wherein polyether acrylates and/or polyether methacrylates are used as component A).

4. Addition products as claimed in claim 1 to 3, wherein N,N-dimethyl-1,3-diaminopropane is used as component B).

5. A process for the preparation of the addition products as claimed in one or more of claims 1 to 4, which comprises reacting esters A) and polyamines B) with one another, if appropriate in an organic solvent, with the use of polymerization inhibitors.

6. Radiation-curable surface coating compositions, which contain the addition products as claimed in claim 1 to 4 and photoinitiators and, if desired, ethy-lenically unsaturated, photopolymerizable compounds and, if desired, further radiation-curable binders and, if desired, further customary auxiliaries and additives and, if desired, water and, if desired, neutralizing agents.

7. Use of the radiation-curable surface coating compositions as claimed in claim 6 for the coating of wood, woodbase materials and paper.