Photoinitiator combination package comprising dedicated bisacylphosphine oxide photoinitiators, further acylphosphine oxide photoinitiators and optical brightener sensitizers

Abstract

A photoinitiator combination package comprising one or more bisacylphosphine oxide photoinitiators, one or more further acylphosphine oxide photoinitiators, and one or more optical brightener sensitizers, a photopolymerizable composition comprising the photoinitiator combination package and a suitable polymerizable compound, a method of polymerizing the photopolymerizable composition and the use of the photoinitiator package in photopolymerization applications.

Description

Technical Field

[0001] This invention relates to a photoinitiator package comprising one or more bisacylphosphine oxide photoinitiators, one or more further acylphosphine oxide photoinitiators, one or more optical brighteners / sensitizers, and optionally one or more amines, wherein the photoinitiator package is a blend that is liquid at 25°C and standard pressure; a photopolymerizable composition comprising the photoinitiator package and a suitable polymerizable compound; a method for polymerizing the photopolymerizable composition; and the use of the photoinitiator package in photopolymerization applications. Background Technology

[0002] Photoinitiators used to promote the free radical polymerization of olefinically unsaturated compounds can be classified into Norrish type I, in which an electronically excited photoinitiator breaks down to form a free radical that initiates free radical polymerization, and Norrish type II, in which an electronically excited photoinitiator extracts a hydrogen radical from another molecule, thereby forming a free radical from said other molecule, which initiates free radical polymerization. While type II photoinitiators require the presence of certain additives / co-initiators, type I photoinitiators typically do not require these additives / co-initiators.

[0003] The development of novel Type I photoinitiators is a key research area in the field of resin curing. In addition to providing novel Type I photoinitiators, we also offer Type I photoinitiator combination packages, in which the activity of the Type I photoinitiator is enhanced by the presence of other compounds such as photosensitizers. These compounds absorb light at wavelengths different from the photoinitiator itself and transfer energy to the photoinitiator, thereby improving the energy absorption of the photoinitiator.

[0004] Phosphorus oxides are a well-known family of type I photoinitiators, providing excellent activity due to the highly reactive phosphonyl radicals formed upon fragmentation. While they are excellent photoinitiators in deep-curing systems, they are known to be far less effective at achieving surface curing. Therefore, blends of phosphorus oxide photoinitiators with other photoinitiators known to be more effective at surface curing are often used to ensure complete curing.

[0005] The degree of interaction between different Type I photoinitiators and sensitizers is difficult to predict and often depends on the structure and energy level of the photoinitiator. Providing highly active photoinitiator packages is desirable because it enables improved photopolymerization without the need to develop new photoinitiators. In particular, improved surface curing capabilities of phosphine oxide photoinitiators will allow for wider application of these powerful photoinitiators. Summary of the Invention

[0006] The observations of this invention are based on the following observations: the combination of a sensitizer and a photoinitiator blend containing certain bisacylphosphine oxide photoinitiators has unexpectedly excellent photoinitiator properties, including surface curing ability.

[0007] Therefore, in a first aspect, the present invention relates to a photoinitiator package comprising, more preferably, the following:

[0008] a) One or more diacylphosphine oxide photoinitiators, each having a structure according to formula (I):

[0009] (I)

[0010] Each instance of R is independently selected from C1-C4 alkyl groups; X is selected from direct single bonds, O, S, NR. 3 -CH2CO2- and -CH2CH2CO2-;

[0011] Where R 1 Selected from C1-C 40 Alkyl groups and C2-C groups separated by one or more O or C3-C8 cycloalkyl groups. 40 Alkyl, wherein the C1-C 40 Alkyl groups or C2-C segments spaced apart 40 Alkyl groups may be unsubstituted or replaced by one or more groups selected from OH and R. 2 Substitution of groups;

[0012] Where R 2 yes ;

[0013] Where R 3 Selected from hydrogen, (CO)R 4 , phenyl, C1-C 12 Alkyl group, C2-C separated by one or more O atoms 12 Alkyl, unsubstituted or C3-C4 substituted with one or more C1-C4 alkyl, C1-C4 alkoxy, OH, or NCO-substituted C3-C 12 cycloalkyl, wherein the C1-C 12 Alkyl groups or C2-C segments spaced apart 12 The alkyl group is either unsubstituted or substituted with one or more C3-C7 cycloalkyl groups, OH, or NCO;

[0014] Where R 4 Selected from C1-C 12 Alkyl groups or C2-C groups separated by one or more O atoms 12 Alkyl, wherein the C1-C 12 Alkyl groups or C2-C segments spaced apart 12The alkyl group is unsubstituted or substituted with one or more C3-C7 cycloalkyl groups, OH, NCO, or a phenyl group substituted with NCO; C3-C 12 Cycloalkyl; C2-C alkyl groups that are unsubstituted or substituted with one or more C1-C4 alkyl groups, OH groups, or C1-C4 alkoxy groups. 10 Alkenyl; unsubstituted or C1-C 12 Alkyl, C1-C 12 Alkoxy, NCO, or C1-C substituted with NCO 12 Alkyl-substituted C6-C 14 Aryl.

[0015] b) One or more further acylphosphine oxide photoinitiators having a structure not according to formula (I), and

[0016] c) One or more optical brighteners / sensitizers, and

[0017] d) Optionally, one or more amines,

[0018] The photoinitiator combination package is a blend that is liquid at 25°C and standard pressure.

[0019] In a second aspect, the present invention relates to a photopolymerizable composition comprising:

[0020] a) One or more olefinically unsaturated compounds that are free radical polymerizable;

[0021] b) Photoinitiator combination packaging according to the first aspect.

[0022] In a third aspect, the present invention relates to a method for use in photocurable photopolymerizable compositions, coatings, adhesives, and inks, said method comprising the following steps in a given sequence:

[0023] a) Coating or printing the photopolymerizable composition according to the second aspect onto a substrate, and

[0024] b) Photopolymerize the coated or printed composition on the substrate using a light source.

[0025] In a final aspect, the present invention relates to the use of the photoinitiator combination package according to the first aspect in the production of printing inks, screen printing inks, gravure printing inks, solder resists, etched offset inks, flexographic printing inks, gravure printing inks, inkjet inks, resist materials, insulators, encapsulants, image recording materials, solder resists, passivation layers, protective coatings, 3D printed objects and molds, holographic applications, fiber optic coatings, waveguides and lenses, overprint varnishes, and coatings for wood, vinyl, metal, and plastics.

[0026] definition

[0027] In this specification, the term "alkyl" or "alkyl group" means, unless otherwise specified, a saturated alkyl chain, whether straight or branched, containing a given number of carbon atoms, and includes all possibilities for the number of carbon atoms in the alkyl group, i.e., for three carbon atoms: n-propyl and isopropyl; for four carbon atoms: n-butyl, isobutyl, sec-butyl, and tert-butyl, etc.

[0028] The term "aryl" or "aryl group" includes, for example, substituted or unsubstituted aryl groups, such as substituted or unsubstituted phenyl groups, substituted or unsubstituted naphthyl groups, anthracene groups, indene groups, and fluorenyl groups.

[0029] The term "heteroaryl" or "heteroaryl group" includes, for example, substituted or unsubstituted aromatic ring systems containing heteroatoms, such as pyridine, pyrrole, furan, triazine, indole, quinolone, thiophene, etc.

[0030] The expression "C1-C separated by one or more oxygen intervals" 40 "Alkyl" refers to an alkyl group in which more than one oxygen atom is present, and these oxygen atoms are separated from each other by at least one methylene group; that is, the oxygen atoms are discontinuous. Examples include: -OCH2OCH3, -OCH2CH2OCH2CH3, -O[CH2CH2O] v CH3, -O[CH2CH2O] v OH, -O[CH2CH2O] v CH2CH3, -CH2O[CH2CH2O] v CH3, where v = 1-19, -O[CH2CH2CH2O] p OH, -O[CH2CH2CH2O] p CH3、-O[CH2CH2CH2O] p CH2CH3, -CH2O[CH2CH2CH2O] p CH3, where p = 1-12.

[0031] When a group is substituted, the term "substituted" means that the group has one or more substituents, which are preferably selected from halogen atoms, alkyl, cycloalkyl, alkoxy, alkylamino, dialkylamino, alkylthio or arylthio, heterocyclic groups; more preferably selected from: methyl, ethyl, isopropyl, tert-butyl, phenyl, trifluoromethyl, cyano, acetyl, ethoxycarbonyl, carboxyl, carboxylate, amino, methylamino, dimethylamino, ethylamino, diethylamino, isopropylamino, diisopropylamino, cyclohexylamino, dicyclohexylamino, etc. Acetamino, piperidinyl, pyrrolyl, methoxy, ethoxy, propoxy, isopropoxy, butoxy, pentoxy, phenoxy, hydroxy, acetoxy, -PO3H, methylthio, ethylthio, isopropylthio, n-propylthio, phenylthio, mercapto, acetylthio, thiocyanate, methyl sulfoxide, methyl sulfone, dimethyl sulfone, sulfonate, fluorine atom, chlorine atom, bromine atom, iodine atom, trimethylsilyl, pentamethyldisilyl, triethylsilyl, trimethyltinyl, furanyl, thiophene, pyridinyl, and morpholino.

[0032] The term "direct bond" refers to a bond that does not have a connecting group and that connects two parts on either side.

[0033] Methylene refers to sp(x) groups bonded to two hydrogen groups. 3 Hybridized carbon, i.e., -CH2R, while methane trimethyl refers to sp(CH2R) bonded to a hydrogen group. 3 Hybridized carbon, i.e. -CHR2.

[0034] Photoinitiators can be classified into Norrish type I, in which an electronically excited photoinitiator breaks down to form a free radical, which is used to initiate free radical polymerization, or Norrish type II, in which an electronically excited photoinitiator extracts a hydrogen free radical from another molecule, thereby forming a free radical from said other molecule, which is used to initiate free radical polymerization, as is well known to those skilled in the art.

[0035] The term "photopolymerization package" refers to a combination of one or more photoinitiators with any component that interacts with said photoinitiator to affect the photoinitiator properties of the photopolymerization package, such as synergists and / or sensitizers. The term "photopolymerization package" does not include photopolymerizable monomers or any other additives that do not affect the photoinitiator properties of the photopolymerization package, such as fillers, pigments, antistatic agents, wetting agents or flow enhancers, adhesion enhancers and / or plasticizers, which are present to alter the properties of the polymerizable composition (e.g., the flow properties of said polymerizable composition) or the mechanical properties or appearance of the resulting cured composition. Furthermore, in the context of this invention, the term "photopolymerization package" means that the components of said package are provided together as a blend, preferably in the form of a blend that is liquid at 25°C and standard pressure.

[0036] In the context of this invention, a blend referred to as a "liquid" must be a single-phase liquid. That is, a blend that is a suspension having a solid phase and a liquid phase is not classified as a "liquid" in the context of this invention, as is an emulsion having multiple immiscible liquid phases. Detailed Implementation

[0037] One or more diacylphosphine oxide photoinitiators

[0038] One of the key features of the photoinitiator combination package of the present invention is one or more diacid phosphine oxide photoinitiators.

[0039] The one or more diacid phosphine oxide photoinitiators each have a structure according to formula (I).

[0040] (I)

[0041] Each instance of R is independently selected from C1-C4 alkyl groups; X is selected from direct single bonds, O, S, NR3, -CH2CO2- and -CH2CH2CO2-;

[0042] Where R 1 Selected from C1-C 40 Alkyl groups and C2-C groups separated by one or more O or C3-C8 cycloalkyl groups. 40 Alkyl, wherein the C1-C 40 Alkyl groups or C2-C segments spaced apart 40 Alkyl groups may be unsubstituted or replaced by one or more groups selected from OH and R. 2 Substitution of groups;

[0043] Where R 2 yes ;

[0044] Where R 3 Selected from hydrogen, (CO)R 4 , phenyl, C1-C 12 Alkyl group, C2-C separated by one or more O atoms 12 Alkyl, unsubstituted or C3-C4 substituted with one or more C1-C4 alkyl, C1-C4 alkoxy, OH, or NCO-substituted C3-C 12 cycloalkyl, wherein the C1-C 12 Alkyl groups or C2-C segments spaced apart 12 Alkyl groups are either unsubstituted or substituted with one or more C3-C7 cycloalkyl groups, OH, or NCO; and

[0045] Where R 4 Selected from C1-C 12 Alkyl groups or C2-C groups separated by one or more O atoms 12 Alkyl, wherein the C1-C12 Alkyl groups or C2-C segments spaced apart 12 The alkyl group is unsubstituted or substituted with one or more C3-C7 cycloalkyl groups, OH, NCO, or a phenyl group substituted with NCO; C3-C 12 Cycloalkyl; C2-C alkyl groups that are unsubstituted or substituted with one or more C1-C4 alkyl groups, OH groups, or C1-C4 alkoxy groups. 10 Alkenyl; unsubstituted or C1-C 12 Alkyl, C1-C 12 Alkoxy, NCO, or C1-C substituted with NCO 12 Alkyl-substituted C6-C 14 Aryl.

[0046] Each instance of R may be independently selected from C1-C4 alkyl groups, namely methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, and tert-butyl. Particularly preferred is that each instance of R is selected from methyl and ethyl. Most preferably, each instance of R is methyl.

[0047] X is selected from direct single bond, O, S, NR. 3 -CH2CO2- and -CH2CH2CO2-. More preferably, X is selected from direct single bonds, O, -CH2CO2- and -CH2CH2CO2-. More preferably, X is selected from direct single bonds -CH2CO2- and -CH2CH2CO2-. Most preferably, X is a direct single bond.

[0048] When X is selected from a direct single bond, -CH2CO2-, and -CH2CH2CO2-, the result is that the phosphorus atom of the bisacylphosphine oxide moiety is bonded to carbon, rather than to oxygen, sulfur, or nitrogen. Bisacylphosphine oxides with phosphorus bonded to carbon (i.e., X selected from a direct single bond, -CH2CO2-, and -CH2CH2CO2-) are particularly preferred due to their improved stability and / or improved photoinitiation properties.

[0049] R 1 Selected from C1-C 40 Alkyl groups and C2-C groups separated by one or more O or C3-C8 cycloalkyl groups. 40 Alkyl, wherein the C1-C 40 Alkyl groups or C2-C segments spaced apart 40 Alkyl groups may be unsubstituted or replaced by one or more groups selected from OH and R. 2 Substitution of groups;

[0050] Where R 2 yes ;

[0051] In some implementations, R is not present. 2This means that the structure according to formula (I) has a single diacylphosphine oxide moiety.

[0052] In such an implementation scheme, R is preferred. 1 Selected from C1-C 20 Alkyl group, -(CH2CH2O-) n CH3 and -(CH2CH2O-) n H, where n is an integer in the range of 1 to 20. R is particularly preferred. 1 For C1-C 20 alkyl.

[0053] Particularly preferred is where X is a single direct bond and R 1 It is C1-C 20 Alkyl-based embodiments. In such embodiments, it is particularly preferred that each instance of R is methyl.

[0054] Similarly, where X is O and R 1 It is -(CH2CH2O-) n CH3 or -(CH2CH2O-) n The embodiment of H is also particularly preferred. In such an embodiment, it is particularly preferred that each instance of R is methyl.

[0055] In other implementations, at least one R 2 This means that the structure according to formula (I) has more than one diacylphosphine oxide moiety.

[0056] Such an implementation scheme is preferably described by equation (I), where R 1 It has the structure according to formula (II):

[0057] (II)

[0058] Each instance of M is independently selected from (CH2CH2O) and (CH2CH(CH3)O); each instance of Y is independently selected from hydrogen and C1-C4 alkyl groups;

[0059] Each instance of Z has the structure CH2(M) 1 ) c R 2 ; where M 1 Each instance is independently selected from (OCH2CH2) and (OCH(CH3)CH2).

[0060] Where a is an integer in the range of 0 to 15;

[0061] Where b is an integer in the range of 0 to 6;

[0062] Each instance of c is an integer in the range 0 to 15;

[0063] Where m is an integer in the range of 0 to 2; and

[0064] Each instance of X is independently selected from -CH2CO2- and -CH2CH2CO2-.

[0065] This structure is typically formed by combining a central polyol core with multiple BAPO-based carboxylic acid residues, wherein ethylene glycol / propylene glycol spacers (i.e., units M and M) are present. 1 )Optionally used to separate the central polyol core from the BAPO-based carboxylic acid residues.

[0066] Suitable polyol nuclei include glycerol, where b=0, m=1 and Y=H; trimethylolpropane, where b=1, m=1 and Y=ethyl; pentaerythritol, where b=1, m=0; neopentyl glycol, where b=1, m=2 and both instances of Y=methyl; ethylene glycol, where b=0, m=2 and both instances of Y=H; and 1,6-hexanediol, where b=4, m=2 and both instances of Y=H.

[0067] Other suitable polyols include propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,2-hexanediol, 1,5-hexanediol, and 2,5-hexanediol. Those skilled in the art will know which values ​​of b and m, and the choice of Y, correspond to these polyols.

[0068] The particularly preferred polyol cores are glycerol, where b=0, m=1 and Y=H; trimethylolpropane, where b=1, m=1 and Y=ethyl; and pentaerythritol, where b=1 and m=0.

[0069] When using a glycerol nucleus, R 1 This is referred to as "optionally ethoxylated / propoxylated glycerol". When using a trimethylolpropane core, R... 1 It is referred to as "optionally ethoxylated / propoxylated trimethylolpropane". When using a pentaerythritol core, R... 1 It is referred to as "optionally ethoxylated / propoxylated pentaerythritol". When using a neopentyl glycol core, R... 1 It is referred to as "optionally ethoxylated / propoxylated neopentyl glycol". When using an ethylene glycol core, R 1 It is referred to as "optionally ethoxylated / propoxylated ethylene glycol". When using a 1,6-hexanediol core, R 1 It is referred to as "optionally ethoxylated / propoxylated 1,6-hexanediol".

[0070] Particularly preferred is that a is an integer in the range of 1 to 15, and each instance of c is an integer in the range of 1 to 15, wherein the sum of each instance of a and c is in the range of 3 to 20, more preferably in the range of 3 to 15, and most preferably in the range of 3 to 10.

[0071] Such implementation schemes are referred to as "ethoxylated / propoxylated polyols", wherein the polyols may be glycerol, trimethylolpropane, pentaerythritol, neopentyl glycol, ethylene glycol, or 1,6-hexanediol.

[0072] R is particularly preferred. 1 Selected from C1-C 20 Alkyl group, -(CH2CH2O-) n CH3 and -(CH2CH2O-) n H, where n is an integer ranging from 1 to 20, ethoxylated / propoxylated glycerol, ethoxylated / propoxylated trimethylolpropane, and ethoxylated / propoxylated pentaerythritol.

[0073] When R 1 It is C1-C 20 When alkyl is used, R is particularly preferred. 1 It is C1-C 15 Alkyl, more preferably C1-C 12 alkyl.

[0074] Examples of particularly preferred diacylphosphine oxide photoinitiators having the structure according to formula (I) include:

[0075] , , , , , , , , , , ,as well as , where each instance of a and each instance of c are independently defined as in equation (II).

[0076] It is particularly preferred that each of the one or more diacid phosphine oxide photoinitiators having the structure according to formula (I) is a liquid at 25°C and standard pressure.

[0077] One or more further acylphosphine oxide photoinitiators

[0078] Another key feature of the photoinitiator combination package according to the invention is the presence of one or more further acylphosphine oxide photoinitiators.

[0079] In the broadest sense, each further acylphosphine oxide photoinitiator can be any acylphosphine oxide photoinitiator having a structure other than that according to formula (I).

[0080] (I)

[0081] Each instance of R is independently selected from C1-C4 alkyl groups; X is selected from direct single bonds, O, S, NR. 3 -CH2CO2- and -CH2CH2CO2-;

[0082] Where R 1 Selected from C1-C 40 Alkyl groups and C2-C groups separated by one or more O or C3-C8 cycloalkyl groups. 40 Alkyl, wherein the C1-C 40 Alkyl groups or C2-C segments spaced apart 40 Alkyl groups may be unsubstituted or replaced by one or more groups selected from OH and R. 2 Substitution of groups;

[0083] Where R 2 yes ;

[0084] Where R 3 Selected from hydrogen, (CO)R 4 , phenyl, C1-C 12 Alkyl group, C2-C separated by one or more O atoms 12 Alkyl, unsubstituted or C3-C4 substituted with one or more C1-C4 alkyl, C1-C4 alkoxy, OH, or NCO-substituted C3-C 12 cycloalkyl, wherein the C1-C 12 Alkyl groups or C2-C segments spaced apart 12 Alkyl groups are either unsubstituted or substituted with one or more C3-C7 cycloalkyl groups, OH, or NCO; and

[0085] Where R 4 Selected from C1-C 12 Alkyl groups or C2-C groups separated by one or more O atoms 12 Alkyl, wherein the C1-C 12 Alkyl groups or C2-C segments spaced apart 12 The alkyl group is unsubstituted or substituted with one or more C3-C7 cycloalkyl groups, OH, NCO, or a phenyl group substituted with NCO; C3-C 12 Cycloalkyl; C2-C alkyl groups that are unsubstituted or substituted with one or more C1-C4 alkyl groups, OH groups, or C1-C4 alkoxy groups. 10 Alkenyl; unsubstituted or C1-C 12 Alkyl, C1-C 12Alkoxy, NCO, or C1-C substituted with NCO 12 Alkyl-substituted C6-C 14 Aryl.

[0086] Each of the one or more further acylphosphine oxide photoinitiators is preferably a monoacylphosphine oxide photoinitiator or a diacylphosphine oxide photoinitiator having a structure not according to formula (I).

[0087] Preferably, one or more monoacylphosphine oxide photoinitiators have a structure according to formula (III):

[0088] (III)

[0089] Where R 1d Each instance is independently selected from C1-C4 alkyl groups; wherein R 2d Selected from C1-C 10 Alkyl, C6-C 10 Aryl groups and their combinations; wherein R 3d Selected from C6-C 10 aryl and OR 5d ;

[0090] Each R 4d Independently selected from hydrogen, C1-C4 alkyl and C(O)R 6d ;

[0091] Where R 5d Selected from hydrogen, C1-C 40 Alkyl groups and C2-C groups separated by one or more O or C3-C8 cycloalkyl groups. 40 Alkyl, wherein the C1-C 40 Alkyl groups or C2-C segments spaced apart 40 Alkyl groups may be unsubstituted or replaced by one or more groups selected from OH and R. 7d Substitution of groups;

[0092] Where R 6d Selected from C1-C4 alkyl, C6-C 10 Aryl groups and their combinations;

[0093] Where R 7d yes

[0094] R 1d Each instance may be independently selected from C1-C4 alkyl groups, specifically methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, and tert-butyl. Particularly preferred is R... 1d Each instance is selected from methyl and ethyl. Most preferably, R 1d Each instance is a methyl group.

[0095] R 2d Preferably selected from C1-C4 alkyl, phenyl, and combinations thereof. Most preferably, R 2d It is a phenyl group.

[0096] R 3d Preferred ingredients are phenyl and OR. 5d The most preferred option is R. 3d Is it OR 5d .

[0097] Each R 4d Preferably, the materials are independently selected from hydrogen and C(O)R. 6d Most preferably, each R 4d It is hydrogen.

[0098] R 6d Preferably selected from C1-C4 alkyl, phenyl, and combinations thereof. Most preferably, R 6d It is a phenyl group.

[0099] R 7d Preferred is Optimal selection .

[0100] In some implementations, R is not present. 7d This means that the structure according to formula (III) has a single monoacylphosphine oxide moiety.

[0101] In such an implementation scheme, R is preferred. 5d Selected from hydrogen, C1-C 20 Alkyl group, -(CH2CH2O-) n CH3 and -(CH2CH2O-) n H, where n is an integer in the range of 1 to 20. R is particularly preferred. 1 It is C1-C 20 Alkyl, more preferably C1-C6 alkyl. Most preferably, R 5d It is an ethyl group.

[0102] In other implementations, there is R 7d At least one instance of which means that the structure according to formula (III) has more than one monoacylphosphine oxide moiety.

[0103] Such an implementation scheme is preferably described by equation (III), where R 5d It has the structure according to formula (IV):

[0104] (IV)

[0105] Each instance of M is independently selected from (CH2CH2O) and (CH2CH(CH3)O); each instance of Y is independently selected from hydrogen and C1-C4 alkyl groups;

[0106] Each instance of Z has the structure CH2(M) 1 ) c R 7d ; where M 1 Each instance is independently selected from (OCH2CH2) and (OCH(CH3)CH2).

[0107] Where a is an integer in the range of 0 to 15;

[0108] Where b is an integer in the range of 0 to 6;

[0109] Each instance of c is an integer independently ranging from 0 to 15; and

[0110] Where m is an integer in the range of 0 to 2.

[0111] This structure is typically formed by combining a central polyol core with multiple monoacylphosphonates, wherein ethylene glycol / propylene glycol spacers (i.e., units M and M) are used. 1 Optionally used to separate the central polyol core from the monoacylphosphonate residue.

[0112] Suitable polyol nuclei include glycerol, where b=0, m=1 and Y=H; trimethylolpropane, where b=1, m=1 and Y=ethyl; pentaerythritol, where b=1, m=0; neopentyl glycol, where b=1, m=2 and both instances of Y=methyl; ethylene glycol, where b=0, m=2 and both instances of Y=H; and 1,6-hexanediol, where b=4, m=2 and both instances of Y=H.

[0113] Other suitable polyols include propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,2-hexanediol, 1,5-hexanediol, and 2,5-hexanediol. Those skilled in the art will know which values ​​of b and m, and the choice of Y, correspond to these polyols.

[0114] The particularly preferred polyol cores are glycerol, where b=0, m=1 and Y=H; trimethylolpropane, where b=1, m=1 and Y=ethyl; and pentaerythritol, where b=1 and m=0.

[0115] When using a glycerin core, R 5d This is referred to as "optionally ethoxylated / propoxylated glycerol". When using a trimethylolpropane core, R... 5d It is referred to as "optionally ethoxylated / propoxylated trimethylolpropane". When using a pentaerythritol core, R...5d It is referred to as "optionally ethoxylated / propoxylated pentaerythritol". When using a neopentyl glycol core, R... 5d It is referred to as "optionally ethoxylated / propoxylated neopentyl glycol". When using an ethylene glycol core, R 5d This is referred to as "optionally ethoxylated / propoxylated ethylene glycol". When using a 1,6-hexanediol core, R 5d It is referred to as "optionally ethoxylated / propoxylated 1,6-hexanediol".

[0116] Particularly preferred is that a is an integer in the range of 1 to 15, and each instance of c is an integer in the range of 1 to 15, wherein the sum of each instance of a and c is in the range of 3 to 20, more preferably in the range of 3 to 15, and most preferably in the range of 3 to 10.

[0117] Such implementation schemes are referred to as "ethoxylated / propoxylated polyols", wherein the polyols may be glycerol, trimethylolpropane, pentaerythritol, neopentyl glycol, ethylene glycol, or 1,6-hexanediol.

[0118] R is the preferred choice 5d Selected from C1-C6 alkyl, ethoxylated / propoxylated glycerol, ethoxylated / propoxylated trimethylolpropane and ethoxylated / propoxylated pentaerythritol.

[0119] Examples of particularly preferred monoacylphosphine oxide photoinitiators having the structure according to formula (III) include:

[0120] , , , ,and , where each instance of a and each instance of c are independent as defined for equation (IV).

[0121] Particularly preferred is that the monoacylphosphine oxide according to formula (III) has the formula according to formula (IIIa), more preferably according to formula (IIIb), and most preferably according to formula (IIIc):

[0122] (IIIa)

[0123] (IIIb)

[0124] (IIIc)

[0125] Where R 1d R 3d R 4d and R 5d As defined for equation (III).

[0126] Particularly preferred is that each of one or more further monoacylphosphine oxide photoinitiators is a liquid at 25°C and standard pressure.

[0127] Suitable combinations of bisacylphosphine oxide photoinitiators having a structure other than formula (I) include, but are not limited to:

[0128] and .

[0129] Among these suitable bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide photoinitiators, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide is preferred.

[0130] It is particularly preferred that each of the one or more further diacylphosphine oxide photoinitiators is a solid at 25°C and standard pressure.

[0131] Particularly preferred is that the further acylphosphine oxide photoinitiator combination package having a structure other than that of formula (I) comprises one or more monoacylphosphine photoinitiators and one or more diacylphosphine oxide photoinitiators having a structure other than that of formula (I).

[0132] One or more optical brighteners and sensitizers

[0133] Another key feature of the photoinitiator combination package according to the invention is the presence of one or more optical brightener sensitizers.

[0134] As those skilled in the art will understand, the term "sensitizer" in "one or more optical brightener sensitizers" explains the purpose of the optical brightener in the photoinitiator combination package and does not limit the choice of optical brighteners that may be used.

[0135] Furthermore, those skilled in the art will fully appreciate that optical brighteners are compounds that absorb light in the ultraviolet and violet regions of the EM spectrum and optically re-emit light in the blue region. Optical brighteners have been used in laundry detergents, papermaking, cosmetics, and textile whitening, as well as in some photopolymerizable compositions to improve the optical properties of the cured composition.

[0136] In the broadest sense, any compound known as an optical brightener may be used in the photoinitiator combination package according to the present invention.

[0137] Examples of such well-known optical brighteners include compounds having structural units including stilbene, triazine, thiazole, benzoxazole, coumarin, xaxone, triazole, oxazole, thiophene, and pyrazoline.

[0138] Optical brighteners having a coumarin or (benzoxazole) core are particularly preferred.

[0139] In a first particularly preferred embodiment, at least one of the one or more optical brightener sensitizers has a structure according to formula (V):

[0140] (V)

[0141] Where R 3a Selected from hydrogen, C1-C 10 Alkyl, C6-C 14 Aryl and C6-C 14 Mixed aromatics,

[0142] R 4a Selected from hydrogen, C1-C 10 Alkyl and OR 1a , and R 5a To R 8a Each of them is independently selected from hydrogen, halogen, alkyl, OR 1a and NR 2a 2;

[0143] Where R 1a Each instance is selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl, and R 2a Each instance is selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl, wherein R 1a To R 8a Each instance can optionally be associated with R 1a To R 8a One or more further instances are combined to form one or more 5- or 6-membered rings.

[0144] In a preferred embodiment, R 3a Selected from hydrogen and C1-C 10 Alkyl, or R 4a Selected from hydrogen and C1-C 10 alkyl.

[0145] In another preferred embodiment, R 3a Selected from hydrogen and C1-C 10 Alkyl, and R 4a Selected from hydrogen and C1-C 10 alkyl.

[0146] In another preferred embodiment, R 7a Selected from OR 1a and NR 2a 2. Optimal Optimum R 7a For NR 2a 2.

[0147] In a particularly preferred embodiment, R 3a Selected from hydrogen and C1-C 10 Alkyl or R 4a Selected from hydrogen and C1-C 10 Alkyl groups, while R 7a Selected from OR 1a and NR 2a 2. Optimal Optimum R 7a For NR 2a 2.

[0148] In a particularly preferred embodiment, R 3a Selected from hydrogen and C1-C 10 Alkyl, R 4a Selected from hydrogen and C1-C 10 Alkyl, and R 7a Selected from OR 1a and NR 2a 2. Optimal Optimum R 7a It is NR 2a 2.

[0149] At least one of the coumarin-based sensitizers, preferably all selected from coumarin, 7-amino-4-(trifluoromethyl)coumarin, 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 7-hydroxy-4-(trifluoromethyl)coumarin, 7-(ethylamino)-4,6-dimethylcoumarin, 7-methoxy-4-(trifluoromethyl)coumarin, 7-ethoxy-4-(trifluoromethyl)coumarin, 7-amino-4-methylcoumarin, 7-(diethylamino)-4-methylcoumarin, 3-(2-benzoxazolyl)-7-(diethylamino)coumarin, 7-methylcoumarin, 7-methoxycoumarin, 4-hydroxycoumarin, 5,7-dimethoxycoumarin, 3-(3 -Biphenyl-4-yl-1,2,3,4-tetrahydro-1-naphthyl)-4-hydroxycoumarin, 6-methylcoumarin, 3-chloro-7-hydroxy-4-methylcoumarin, 7-hydroxycoumarin, 7-hydroxy-6-methoxycoumarin, 7-methoxy-6-hydroxycoumarin, 6-hydroxycoumarin, 7,8-dihydroxy-4-methylcoumarin, 7-hydroxy-4-methylcoumarin, 7-(dimethylamino)-4-methylcoumarin, 2,3,6,7-tetrahydro-9-methyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolinazine-11-one, 7-(diethylamino)-4-(trifluoromethyl)coumarin and 7-(ethylamino)-4-(trifluoromethyl)coumarin.

[0150] More preferably, at least one, and preferably all, of the coumarin-based sensitizers are selected from coumarin, 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 7-methoxy-4-(trifluoromethyl)coumarin, 7-ethoxy-4-(trifluoromethyl)coumarin, 7-(diethylamino)-4-methylcoumarin, 3-(2-benzoxazolyl)-7-(diethylamino)coumarin, 7-methylcoumarin, 7-Methoxycoumarin, 5,7-dimethoxycoumarin, 6-methylcoumarin, 7-(dimethylamino)-4-methylcoumarin, 2,3,6,7-tetrahydro-9-methyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolinazine-11-one, 7-(diethylamino)-4-(trifluoromethyl)coumarin and 7-(ethylamino)-4-(trifluoromethyl)coumarin.

[0151] Most preferably, at least one, and preferably all, of the coumarin-based sensitizers are selected from coumarin, 7-(diethylamino)-4-methylcoumarin, 7-methylcoumarin, 7-methoxycoumarin, 5,7-dimethoxycoumarin, and 7-(diethylamino)-4-(trifluoromethyl)coumarin.

[0152] In a second particularly preferred embodiment, at least one of the one or more optical brightener sensitizers has a structure according to formula (VI):

[0153] (VI)

[0154] Where R 1b To R 4b Each of them is independently selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl, wherein R 1b and R 2b They can combine to form a 6-membered saturated or unsaturated ring, which can be one or more selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl substituents are used for substitution, and R is used for substitution. 3b and R 4b They can combine to form a 6-membered saturated or unsaturated ring, which can be one or more selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl substituent substitution; and wherein A represents a linking group represented by any one of the following formulas (VII) to (XI):

[0155] (VII)

[0156] (VIII)

[0157] (IX)

[0158] (X)

[0159] (XI)

[0160] Each of them This indicates the bond position of A in each formula.

[0161] R 1b To R 4b Each of them is independently selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl, wherein R 1b and R 2b They can combine to form a 6-membered saturated or unsaturated ring, which can be one or more selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl substituents are used for substitution, and R is used for substitution. 3b and R 4b They can combine to form a 6-membered saturated or unsaturated ring, which can be one or more selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Substituents of aryl groups.

[0162] In one implementation, R 1b To R 4b Each of them is independently selected from hydrogen, C1-C6 alkyl and C6-C 10 Aryl.

[0163] In a particularly preferred embodiment, R 1b and R 3b Both are related to R. 2b and R 4b Combined to form a 6-membered saturated or unsaturated ring, which may be one or more selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Substituents of aryl groups.

[0164] In one embodiment of the particularly preferred embodiment, each 6-membered ring formed is aromatic, meaning that at least one of the one or more oxazolyl sensitizers is a benzoxazolyl sensitizer having a structure according to formula (XII):

[0165] (XII)

[0166] Where R 1c To R 8c Each of them is independently selected from hydrogen, C1-C 10 Alkyl and C6-C14 Aryl.

[0167] Preferably, R 1c To R 8c Each of them is independently selected from hydrogen, C1-C6 alkyl and C6-C 10 Aryl.

[0168] In one embodiment, each of one or more oxazolyl sensitizers has a structure according to formula (XII).

[0169] In other embodiments, at least one of one or more oxazolyl sensitizers has a structure according to formula (XII), while any remaining oxazolyl sensitizers in the photoinitiator package have other structures according to formula (VI).

[0170] Particularly preferred compounds according to formula (VI) include 2,5-thiophene dimethylbis(5-tert-butyl-1,3-benzoxazole), 2,2'-(vinylene-p-phenylene)bisbenzoxazole, 2,2'-(naphthalene-1,4-dimethyl)bis(benzoxazole), 2-[4-[2-[4-(benzoxazole-2-yl)phenyl]vinyl]phenyl]-5-methylbenzoxazole, and 2,2'-(1,4-phenylene)bis[5-phenyloxazole].

[0171] One or more amines

[0172] The optional components of the photoinitiator package are one or more amines.

[0173] In the broadest sense, one or more amines according to the invention can be any amine, including aliphatic, alicyclic, aromatic, aryl-aliphatic, heterocyclic, oligomeric, or polymeric amines. They can be primary, secondary, or tertiary amines, such as butylamine, dibutylamine, tributylamine, cyclohexylamine, benzyldimethylamine, dicyclohexylamine, N-phenylglycine, triethylamine, phenyl-diethanolamine, triethanolamine, piperidine, piperazine, morpholine, quinolone, esters of dimethylaminobenzoic acid, and their corresponding derivatives. Furthermore, amine-modified acrylates can be used. Examples of such amine-modified acrylates include acrylates modified by reaction with primary or secondary amines, as described in US 3,844,916, EP 280222, US 5,482,649, or US 5,734,002.

[0174] Also suitable for use are those polyfunctional amines and polymeric amine derivatives such as Omnipol ASA from IGM Resins BV, Genopol AB-2 from Rahn AG, Speedcure 7040 from Lambson Limited, or those described in US2013 / 0012611.

[0175] Those skilled in the art will understand that the term "amine" does not include amides or imides, regardless of whether the nitrogen in the amide / imide is bonded to an alkyl group. Similarly, ammonium salts are not amines.

[0176] Preferably, the one or more amines are not type I or type II photoinitiators, such as well-known aminoketone type I initiators. More preferably, the one or more amines are not optical brighteners, i.e., compounds that absorb light in the ultraviolet and violet regions of the EM spectrum and optically re-emit light in the blue region. Therefore, it is clear that the sole role of the amines in the photopolymerization package is to act as synergists, thereby improving the effects of the one or more bisacylphosphine oxide photoinitiators having the structure according to formula (I) and / or the one or more optical brightener sensitizers.

[0177] Preferably, one or more amines have so-called α-hydrogen, i.e., hydrogen bonded to a carbon atom directly bonded to the nitrogen atom of the amine. Particularly preferred is that this hydrogen is bonded to sp... 3 - Hybridized carbon bonds. Therefore, amines preferably have nitrogen atoms that have direct single bonds with methyl (i.e., CH3), methylene (i.e., CH2 of CH2R), or methanetriyl (i.e., CH of CHR2).

[0178] Without being bound by theory, it is believed that α-hydrogen can be readily abstracted by free radicals to form stable α-amino groups, which can play a role in increasing the curing rate, especially by scavenging molecular oxygen, which can delay the polymerization reaction.

[0179] Particularly preferred is that the nitrogen atom is bonded to at least one alkyl group. More preferably, the nitrogen atom is bonded to at least two alkyl groups.

[0180] In a particularly preferred embodiment, the one or more amines are independently selected from those having the formula NR. A R B R C amines, of which R A and R B Independently selected from optionally substituted alkyl groups, and R C Selected from optionally substituted alkyl and optionally substituted aryl groups.

[0181] In the described embodiments, the term "optionally substituted aryl" does not include aryl groups having two or more substituents that are linked to form a fused ring system, such as quinoline, indole, or coumarin. Similarly, the term "optionally substituted alkyl" does not include substitutions that would cause the group to no longer be considered an alkyl group, such as acyl groups (i.e., =O substitution at the first carbon atom of the alkyl chain).

[0182] Photoinitiator Combination Pack

[0183] The photoinitiator combination of the present invention comprises one or more diacid phosphine oxide photoinitiators as described above and one or more optical brightener sensitizers as described above.

[0184] Preferably, the photoinitiator package comprises, and more preferably comprises, the following:

[0185] a) One or more bisacylphosphine oxide photoinitiators having the structure of formula (I) in an amount ranging from 15 to 40% by weight, more preferably from 18 to 35% by weight, and most preferably from 19 to 30% by weight, relative to the total weight of the photoinitiator combination package.

[0186] b) One or more acylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 30 to 75% by weight, more preferably from 40 to 70% by weight, and most preferably from 50 to 60% by weight, relative to the total weight of the photoinitiator combination package.

[0187] c) The amount of one or more optical brighteners / sensitizers in a range of 5 to 30% by weight, more preferably 10 to 25% by weight, and most preferably 15 to 22% by weight, relative to the total weight of the photoinitiator combination package; and

[0188] d) Optionally, one or more amines in an amount ranging from 1 to 30% by weight, more preferably from 3 to 25% by weight, and most preferably from 5 to 20% by weight, relative to the total weight of the photoinitiator combination package.

[0189] In one embodiment, the photoinitiator assembly package comprises, more preferably, the following:

[0190] a) One or more bisacylphosphine oxide photoinitiators having the structure of formula (I) in an amount ranging from 15 to 40% by weight, more preferably from 18 to 35% by weight, and most preferably from 19 to 30% by weight, relative to the total weight of the photoinitiator combination package.

[0191] b) One or more acylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 30 to 75% by weight, more preferably from 40 to 70% by weight, and most preferably from 50 to 60% by weight, relative to the total weight of the photoinitiator combination package.

[0192] c) One or more optical brightener sensitizers in an amount ranging from 5 to 30% by weight, more preferably from 10 to 25% by weight, and most preferably from 15 to 22% by weight, relative to the total weight of the photoinitiator combination package; and

[0193] d) One or more amines in an amount ranging from 1 to 30% by weight, more preferably from 3 to 25% by weight, and most preferably from 5 to 20% by weight, relative to the total weight of the photoinitiator combination package.

[0194] In another embodiment, the photoinitiator package comprises, more preferably, the following:

[0195] a) One or more bisacylphosphine oxide photoinitiators having the structure according to formula (I) in an amount ranging from 15 to 40% by weight, more preferably from 18 to 35% by weight, and most preferably from 19 to 30% by weight, relative to the total weight of the photoinitiator combination package.

[0196] b) one or more acylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 30 to 75% by weight, more preferably from 40 to 70% by weight, and most preferably from 50 to 60% by weight, relative to the total weight of the photoinitiator assembly; and

[0197] c) One or more optical brightener sensitizers in an amount ranging from 5 to 30% by weight, more preferably from 10 to 25% by weight, and most preferably from 15 to 22% by weight, relative to the total weight of the photoinitiator combination package.

[0198] Particularly preferred is that the photoinitiator package comprises, and more preferably comprises, the following:

[0199] a) One or more bisacylphosphine oxide photoinitiators having a structure according to formula (I) in an amount ranging from 18% to 35% by weight relative to the total weight of the photoinitiator assembly package;

[0200] b) One or more acylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 40% to 70% by weight relative to the total weight of the photoinitiator assembly package;

[0201] c) One or more optical brighteners / sensitizers in an amount ranging from 10 to 25% by weight relative to the total weight of the photoinitiator assembly; and

[0202] d) Optionally, one or more amines in an amount ranging from 3 to 25% by weight relative to the total weight of the photoinitiator assembly.

[0203] Particularly preferred is that the photoinitiator package comprises, and more preferably comprises, the following:

[0204] a) One or more bisacylphosphine oxide photoinitiators having a structure according to formula (I) in an amount ranging from 19 to 30% by weight relative to the total weight of the photoinitiator assembly package;

[0205] b) One or more acylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 50 to 60% by weight relative to the total weight of the photoinitiator assembly;

[0206] c) One or more optical brighteners / sensitizers in an amount ranging from 15 to 22% by weight relative to the total weight of the photoinitiator assembly; and

[0207] d) Optionally, one or more amines in an amount ranging from 5% to 20% by weight relative to the total weight of the photoinitiator assembly.

[0208] As described above, the one or more further acylphosphine oxide photoinitiators preferably comprise one or more monoacylphosphine photoinitiators and one or more diazylphosphine oxide photoinitiators having a structure not according to formula (I).

[0209] In such an implementation, the photoinitiator package preferably comprises, and more preferably, the following:

[0210] a) One or more bisacylphosphine oxide photoinitiators having the structure according to formula (I) in an amount ranging from 15 to 40% by weight, more preferably from 18 to 35% by weight, and most preferably from 19 to 30% by weight, relative to the total weight of the photoinitiator combination package.

[0211] b) One or more bisacylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 1 to 30% by weight, more preferably from 4 to 20% by weight, and most preferably from 7 to 15% by weight, relative to the total weight of the photoinitiator combination package.

[0212] c) One or more monoacylphosphine oxide photoinitiators in an amount ranging from 30 to 70% by weight, more preferably from 35 to 60% by weight, and most preferably from 40 to 55% by weight, relative to the total weight of the photoinitiator combination package.

[0213] d) One or more optical brightener sensitizers in an amount ranging from 5 to 30% by weight, more preferably from 10 to 25% by weight, and most preferably from 15 to 22% by weight, relative to the total weight of the photoinitiator combination package; and

[0214] e) Optionally, one or more amines in an amount ranging from 1 to 30% by weight, more preferably from 3 to 25% by weight, and most preferably from 5 to 20% by weight, relative to the total weight of the photoinitiator combination package.

[0215] Preferably, the photoinitiator package comprises, and more preferably comprises, the following:

[0216] a) One or more bisacylphosphine oxide photoinitiators having a structure according to formula (I) in an amount ranging from 18% to 35% by weight relative to the total weight of the photoinitiator assembly package;

[0217] b) One or more bisacylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 4 to 20% by weight relative to the total weight of the photoinitiator assembly package;

[0218] c) One or more monoacylphosphine oxide photoinitiators in an amount ranging from 35% to 60% by weight relative to the total weight of the photoinitiator assembly package;

[0219] d) One or more optical brighteners / sensitizers in an amount ranging from 10 to 25% by weight relative to the total weight of the photoinitiator combination package; and

[0220] e) Optionally, one or more amines in an amount ranging from 3 to 25% by weight relative to the total weight of the photoinitiator assembly.

[0221] Particularly preferred is that the photoinitiator package preferably comprises, and more preferably comprises, the following:

[0222] a) One or more bisacylphosphine oxide photoinitiators having a structure according to formula (I) in an amount ranging from 19 to 30% by weight relative to the total weight of the photoinitiator assembly package;

[0223] b) One or more bisacylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 7 to 15% by weight relative to the total weight of the photoinitiator combination package;

[0224] c) One or more monoacylphosphine oxide photoinitiators in an amount ranging from 40% to 55% by weight relative to the total weight of the photoinitiator combination package;

[0225] d) One or more optical brightener sensitizers in an amount ranging from 15 to 22% by weight relative to the total weight of the photoinitiator combination package; and

[0226] e) Optionally, one or more amines in an amount ranging from 5% to 20% by weight relative to the total weight of the photoinitiator assembly.

[0227] Preferably, the photoinitiator package comprises, and more preferably comprises, the following:

[0228] a) One or more bisacylphosphine oxide photoinitiators having the structure according to formula (I) in an amount ranging from 15 to 40% by weight, more preferably from 18 to 35% by weight, and most preferably from 19 to 30% by weight, relative to the total weight of the photoinitiator combination package.

[0229] b) One or more bisacylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 1 to 30% by weight, more preferably from 4 to 20% by weight, and most preferably from 7 to 15% by weight, relative to the total weight of the photoinitiator combination package.

[0230] c) One or more monoacylphosphine oxide photoinitiators in an amount ranging from 30 to 70% by weight, more preferably from 35 to 60% by weight, and most preferably from 40 to 55% by weight, relative to the total weight of the photoinitiator combination package.

[0231] d) One or more optical brightener sensitizers in an amount ranging from 5 to 30% by weight, more preferably from 10 to 25% by weight, and most preferably from 15 to 22% by weight, relative to the total weight of the photoinitiator combination package; and

[0232] e) Optionally, one or more amines in an amount ranging from 1 to 30% by weight, more preferably from 3 to 25% by weight, and most preferably from 5 to 20% by weight, relative to the total weight of the photoinitiator combination package.

[0233] In one embodiment, the photoinitiator package preferably comprises, more preferably, the following:

[0234] a) One or more bisacylphosphine oxide photoinitiators having the structure according to formula (I) in an amount ranging from 15 to 40% by weight, more preferably from 18 to 35% by weight, and most preferably from 19 to 30% by weight, relative to the total weight of the photoinitiator combination package.

[0235] b) One or more bisacylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 1 to 30% by weight, more preferably from 4 to 20% by weight, and most preferably from 7 to 15% by weight, relative to the total weight of the photoinitiator combination package.

[0236] c) One or more monoacylphosphine oxide photoinitiators in an amount ranging from 30 to 70% by weight, more preferably from 35 to 60% by weight, and most preferably from 40 to 55% by weight, relative to the total weight of the photoinitiator assembly; and

[0237] d) One or more optical brightener sensitizers in an amount ranging from 5 to 30% by weight, more preferably from 10 to 25% by weight, and most preferably from 15 to 22% by weight, relative to the total weight of the photoinitiator combination package.

[0238] In another embodiment, the photoinitiator package preferably comprises, more preferably, the following:

[0239] a) One or more bisacylphosphine oxide photoinitiators having the structure according to formula (I) in an amount ranging from 15 to 40% by weight, more preferably from 18 to 35% by weight, and most preferably from 19 to 30% by weight, relative to the total weight of the photoinitiator combination package.

[0240] b) One or more bisacylphosphine oxide photoinitiators having a structure not according to formula (I) in an amount ranging from 1 to 30% by weight, more preferably from 4 to 20% by weight, and most preferably from 7 to 15% by weight, relative to the total weight of the photoinitiator combination package.

[0241] c) One or more monoacylphosphine oxide photoinitiators in an amount ranging from 30 to 70% by weight, more preferably from 35 to 60% by weight, and most preferably from 40 to 55% by weight, relative to the total weight of the photoinitiator combination package.

[0242] d) One or more optical brightener sensitizers in an amount ranging from 5 to 30% by weight, more preferably from 10 to 25% by weight, and most preferably from 15 to 22% by weight, relative to the total weight of the photoinitiator combination package; and

[0243] e) One or more amines in an amount ranging from 1 to 30% by weight, more preferably from 3 to 25% by weight, and most preferably from 5 to 20% by weight, relative to the total weight of the photoinitiator assembly.

[0244] In addition, the photoinitiator combination package is required to exist in the form of a blend that is liquid at 25°C and standard pressure.

[0245] This means that the one or more diazygium oxides, the one or more further zygium oxides photoinitiators, the one or more optical brightener sensitizers, and optionally one or more amines must be miscible and form a stable liquid blend at the indicated temperature and pressure, rather than existing, for example, as a mixture of dry powders or as a suspension or emulsion.

[0246] Particularly preferred is that the photoinitiator combination package exists in the form of a blend, which is liquid at 25°C and standard pressure, and has a viscosity in the range of 1000 to 15000 cP, more preferably 3000 to 13000 cP, and most preferably 5000 to 12000 cP, as determined by the method described in the determination method. This low viscosity makes the liquid-stabilized blend easy to process.

[0247] Photopolymerizable compositions

[0248] In a second aspect, the present invention also relates to a photopolymerizable composition.

[0249] In the broadest sense, photopolymerizable compositions comprise or consist of the following:

[0250] a) One or more olefinically unsaturated compounds that are free radical polymerizable;

[0251] b) The photoinitiator combination package according to the first aspect.

[0252] Preferably, the photopolymerizable composition comprises or consists of the following:

[0253] a) One or more olefinically unsaturated free radical polymerizable compounds in an amount ranging from 30 to 99.0% by weight, more preferably from 50 to 95.0% by weight, and most preferably from 70 to 90% by weight, relative to the total weight of the photopolymerizable composition;

[0254] b) The amount of the photoinitiator package according to the first aspect in the range of 0.5 to 50% by weight, more preferably 0.8 to 40% by weight, and most preferably 1.0 to 30% by weight, relative to the total weight of the photopolymerizable composition.

[0255] In addition to one or more olefinically unsaturated free radical polymerizable compounds and a photoinitiator package according to the first aspect, the photopolymerizable composition may contain other components, as well as those well known to those skilled in the art.

[0256] Suitable further components include photosensitizers, further photoinitiators, pigments, binders, and conventional additives.

[0257] Therefore, the photopolymerizable composition comprises, more preferably, the following:

[0258] a) One or more olefinically unsaturated free radical polymerizable compounds in an amount ranging from 30 to 99.0% by weight, more preferably from 50 to 95.0% by weight, and most preferably from 70 to 90% by weight, relative to the total weight of the photopolymerizable composition;

[0259] b) A photoinitiator package according to the first aspect in an amount ranging from 0.5% to 50% by weight, more preferably from 0.8% to 40% by weight, and most preferably from 1.0% to 30% by weight, relative to the total weight of the photopolymerizable composition;

[0260] c) Optionally, in an amount ranging from 0.5% to 30% by weight, more preferably from 0.8% to 20% by weight, and most preferably from 1.0% to 15% by weight, one or more further photoinitiators, one or more photosensitizers and / or one or more co-initiators;

[0261] d) Optionally, one or more pigments are used in an amount ranging from 0.1% to 30% by weight, more preferably from 1.0% to 25% by weight, and most preferably from 10% to 20% by weight, relative to the total weight of the photopolymerizable composition;

[0262] e) Optionally, one or more adhesives are used in an amount ranging from 5.0 to 60% by weight, more preferably from 8.0 to 50% by weight, and most preferably from 10 to 40% by weight, relative to the total weight of the photopolymerizable composition; and

[0263] f) Optionally, one or more additives are used in an amount ranging from 0.01 to 10% by weight, more preferably from 0.01 to 8.0% by weight, and most preferably from 0.01 to 5.0% by weight, relative to the total weight of the photopolymerizable composition.

[0264] Furthermore, the photopolymerizable composition can be formulated into a composition further comprising water and / or a solvent, such as an organic solvent.

[0265] Preferably, there are no further photoinitiators, photosensitizers, or co-initiators other than those that form part of the photoinitiator assembly. In other words, all components that contribute to the photopolymerization properties of the photoinitiator are preferably included in the photoinitiator assembly, as defined above and below.

[0266] There are no particular limitations on the selection of one or more olefinically unsaturated, free-radical polymerizable compounds. These compounds may contain one or more olefinic double bonds. They may be low molecular weight (monomers) or high molecular weight (oligomers) compounds.

[0267] Examples of suitable low molecular weight polymerizable compounds (monomers) having a double bond are alkyl or hydroxyalkyl acrylates or methacrylates, such as methyl-, ethyl-, butyl-, 2-ethylhexyl-, 2-hydroxyethyl-, or isobornyl-acrylates; and methyl methacrylate or ethyl methacrylate. A further example 5 is a silicone or fluorine-modified resin, such as a siloxane acrylate. Further examples of these polymerizable compounds are acrylonitrile, acrylamide, methacrylamide, N-substituted (meth)acrylamide, styrene, alkylstyrene and halostyrene, vinyl esters such as vinyl acetate, vinyl ethers such as isobutyl vinyl ether, N-vinylpyrrolidone, vinyl chloride, or vinylidene chloride.

[0268] Examples of polymerizable compounds having more than one double bond are ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, hexamethylene glycol diacrylate, bisphenol A diacrylate, 4,4'-bis-(2-acryloyloxyethoxy)-diphenylpropane, trimethylolpropane triacrylate, pentaerythritol triacrylate or tetraacrylate, vinyl acrylate, divinylbenzene, divinyl succinate, diallyl phthalate, triallyl phosphate, triallyl isocyanurate, or tri-(2-acryloylethyl)isocyanurate.

[0269] Examples of high molecular weight (oligomeric) polyunsaturated compounds are acrylated epoxy resins, acrylated or vinyl ether- or epoxy-containing polyesters, acrylated polyurethanes, or acrylated polyethers.

[0270] A further example of unsaturated oligomers is unsaturated polyester resin, which is typically prepared from maleic acid, phthalic acid, and one or more diols, and has a molecular weight of approximately 500 Da to 3,000 Da. Such unsaturated oligomers may also be referred to as prepolymers.

[0271] Examples of polymerizable compounds particularly suitable for carrying out the present invention are esters of olefinically unsaturated carboxylic acids and polyols or poly(poly)epoxides, and polymers containing olefinically unsaturated groups in the chain or side groups, such as unsaturated polyesters, polyamides and polyurethanes and their copolymers, alkyl resins, polybutadiene and butadiene copolymers, polyisoprene and isoprene copolymers, polymers and copolymers having (meth)acrylic acid groups in the side chains, and mixtures thereof.

[0272] Illustrative examples of unsaturated carboxylic acids or anhydrides that can be used to prepare the above-mentioned esters are acrylic acid, methacrylic acid, maleic anhydride, crotonic acid, itaconic acid, cinnamic acid, and unsaturated fatty acids such as linolenic acid and oleic acid. Acrylic acid and methacrylic acid are preferred.

[0273] Examples of polyols that can also be esterified are aromatic, aliphatic, and alicyclic polyols, with aliphatic and alicyclic polyols being preferred. Aromatic polyols include, for example, hydroquinone, 4,4'-dihydroxybiphenyl, 2,2-bis(4-hydroxyphenyl)propane, as well as phenolic varnishes and methyl phenolic resins.

[0274] Esterifiable polyepoxides include those based on the polyols, particularly the reaction products between aromatic polyols and epichlorohydrins. Also suitable as polyols are polymers and copolymers containing hydroxyl groups in the polymer chain or side groups, such as polyvinyl alcohol and its copolymers, or polyhydroxyalkyl methacrylate or its copolymers. Further suitable polyols are low-polymer polyesters with hydroxyl end groups.

[0275] Examples of aliphatic and alicyclic polyols include preferably alkyl diols containing 2 to 12 carbon atoms, such as ethylene glycol, 1,2- or 1,3-propanediol, 1,2-, 1,3- or 1,4-butanediol, pentanediol, hexanediol, octanediol, dodecanediol, diethylene glycol, triethylene glycol, polyethylene glycol with a molecular weight preferably from 200 Da to 1,500 Da, 1,3-cyclopentanediol, 1,2-, 1,3- or 1,4-cyclohexanediol, 1,4-dihydroxymethylcyclohexane, glycerol, tri(β-hydroxyethyl)amine, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, and sorbitol.

[0276] Further suitable olefinically unsaturated compounds are unsaturated polyamides obtained from unsaturated carboxylic acids and aromatic, aliphatic, and cycloaliphatic polyamines, said polyamines preferably having 2 to 6 amino groups, more preferably 2 to 4 amino groups. Examples of such polyamines are: ethylenediamine, 1,2- or 1,3-propanediamine, 1,2-, 1,3- or 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, octanediamine, dodecanediamine, 1,4-diaminocyclohexane, isophoronediamine, phenylenediamine, bisphenylenediamine, di-(β-aminoethyl) ether, diethylenetriamine, triethylenetetramine, and di(β-aminoethoxy)- and di(β-aminopropoxy)ethane. Other suitable polyamines are polymers and copolymers that may contain additional amino groups in the side chain, as well as oligoamides containing amino-terminal groups.

[0277] Specific examples of such unsaturated polyamides are methylenebisacrylamide, 1,6-hexamethylenebisacrylamide, diethylenetriaminetrimethylacrylamide, bis(methacrylamidopropoxy)ethane, and N-[(β-hydroxyethoxy)ethyl]acrylamide.

[0278] Unsaturated polyurethanes are also suitable for carrying out the invention as polymerizable compounds, such as those derived from saturated or unsaturated diisocyanates and unsaturated or saturated diols.

[0279] Polybutadiene and polyisoprene and their copolymers can also be used.

[0280] Suitable polymerizable compounds include, for example, olefins such as ethylene, propylene, butene, and hexene, (meth)acrylates, acrylonitrile, styrene, and vinyl chloride. Polymers having unsaturated (meth)acrylate groups in their side chains can also be used as compounds that are free radically polymerizable by one or more olefinically unsaturated groups. These are typically reaction products of epoxy resins based on phenolic varnishes and (meth)acrylic acid; homopolymers or copolymers of vinyl alcohol or its hydroxyalkyl derivatives esterified with (meth)acrylate; and homopolymers and copolymers of (meth)acrylates esterified with hydroxyalkyl (meth)acrylates.

[0281] Examples of photosensitizers are those commonly used in the art, such as benzophenone, thioxanthone, anthraquinone and 3-acylcoumarin derivatives, terphenyl, styryl ketone and 3-(aromatic acyl methylene)-thiazoline, camphorquinone and eosin, rhodamine and erythrosine dyes.

[0282] Examples of thioxanthones include thioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-dodecylthioxanthone, 2,4-diethylthioxanthone, 2,4-dimethylthioxanthone, 1-methoxycarbonylthioxanthone, 2-ethoxycarbonylthioxanthone, 3-(2-methoxyethoxycarbonyl)thioxanthone, 4-butoxycarbonylthioxanthone, 3-butoxycarbonyl-7-methylthioxanthone, 1-cyano-3-chlorothioxanthone, 1-ethoxycarbonyl-3-chlorothioxanthone, 1-ethoxycarbonyl-3-ethoxythioxanthone, 1-ethoxycarbonyl-3-aminothioxanthone, 1-ethoxycarbonyl-3-phenylthioxanthone, 3,4-bis[2-(2-methoxyethoxy)ethoxycarbonyl]thioxanthone, 1-ethoxycarbonyl-3-(1-methyl-1-morpholinoethyl)thioxanthone, 2-methyl- 6-Dimethoxymethylthioxanthone, 2-methyl-6-(1,1-dimethoxybenzyl)thioxanthone, 2-morpholinemethylthioxanthone, 2-methyl-6-morpholinemethylthioxanthone, N-allylthioxanthone-3,4-dicarboxylimide, N-octylthioxanthone-3,4-dicarboxylimide, N-(1,1,3,3-tetramethylbutyl)thioxanthone-3,4-dicarboxylimide, 1-phenoxythioxanthone, 6-ethoxycarbonyl-1-2-methoxythioxanthone, 6-ethoxycarbonyl-2-methylthioxanthone, thioxanthone-2-polyethylene glycol ester, 2-hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthone-2-oxy)-N,N,N-trimethyl-1-propanemium chloride, or patent application PCT / EP2011 / 069514 The compounds described herein include, for example, n-dodecyl-7-methyl-thioxanthone-3-carboxylic acid ester and N,N-diisobutyl-7-methyl-thioxanthone-3-carboxamide. Additionally, polymeric thioxanthone derivatives (e.g., Omnipol® TX from IGM Resins BV, Genopol® TX-1 from Rahn AG, and Speedcure® 7010 from Lambson Limited) are also applicable.

[0283] Examples of benzophenone include benzophenone, 4-phenylbenzophenone, 4-methoxybenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-dimethylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, 4-(4-methylthiophenyl)benzophenone, 3,3'-dimethyl-4-methoxybenzophenone, methyl 2-benzoylbenzoate, and 4-(2-hydroxyethylthio)benzophenone. Benzophenone, 4-(4-toluenethio)benzophenone, 4-benzoyl-N,N,N-trimethylbenzylmethylammonium chloride, 2-hydroxy-3-(4-benzoylphenoxy)-N,N,N-trimethyl-1-propanemium chloride monohydrate, 4-(13-acryloyl-1,4,7,10,13-pentatridecyl)benzophenone, 4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyl)oxyethyl]benzylmethylammonium chloride, or compounds described in U.S. Patent US9938231 (e.g., Omnirad® 991 from IGM Resins BV).

[0284] Also suitable are polymeric benzophenone derivatives (e.g., Omnipol® BP, Omnipol® 2702 and Omnipol® 682 all from IGM Resins BV, Genopol® from Rahn AG and Speedcure BP-2® 7005 from Lambson Limited).

[0285] Examples of 3-acylcoumarin derivatives are 3-benzoylcoumarin, 3-benzoyl-7-methoxycoumarin, 3-benzoyl-5,7-di(propoxy)coumarin, 3-benzoyl-6,8-dichlorocoumarin, 3-benzoyl-6-chlorocoumarin, 3,3'-carbonylbis[5,7-di(propoxy)coumarin], 3,3'-carbonylbis(7-methoxycoumarin), 3,3'-carbonylbis(7-diethylaminocoumarin), 3-isobutyrylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-5,7-diethoxycoumarin, and 3-benzoyl-5,7-dibutyrylcoumarin. Coumarin, 3-benzoyl-5,7-di(methoxyethoxy)coumarin, 3-benzoyl-5,7-di(allyloxy)coumarin, 3-benzoyl-7-dimethylaminocoumarin, 3-benzoyl-7-diethylaminocoumarin, 3-isobutyryl-1,7-dimethylaminocoumarin, 5,7-dimethoxy-3-(1-naphthoyl)coumarin, 5,7-dimethoxy-3-(1-naphthoyl)coumarin, 3-benzoylbenzo[f]coumarin, 7-diethylamino-3-thiophenecarboxylcoumarin, 3-(4-cyanobenzoyl)-5,7-dimethoxycoumarin, or those described in EP2909243 and WO2017216699.

[0286] Examples of 3-(aromaticylmethylene)thiazoline are 3-methyl-1,2-benzoylmethylene-β-naphthothiazoline, 3-methyl-2-benzoylmethylene-benzothiazoline, and 3-ethyl-2-propionylmethylene-β-naphthothiazoline.

[0287] Other examples of aromatic carbonyl compounds are acetylbenzene, 3-methoxyacetylbenzene, 4-phenylacetylbenzene, benzil (e.g., the one described in WO 2013 / 164394), 2-acetylnaphthalene, 2-naphthocarbamate, 9,10-anthraquinone, 9-fluorenone, dibenzocycloheptanone, xanthonone, 2,5-bis(4-diethylaminobenzyl)cyclopentanone, α-(p-dimethylaminobenzyl)ones, such as 2-(4-dimethylaminobenzyl)ind-1-one or 3-(4-dimethylaminophenyl)-1-ind-5-ylpropenone, 3-phenylthiophthalimide, N-methyl-3,5-di(ethylthio)phthalimide.

[0288] Thioxanone and 3-acylcoumarin are particularly preferred.

[0289] It was observed that the aforementioned photosensitizers improved the activity of the one or more diacid phosphine oxide photoinitiators without shortening the shelf life of the composition. Furthermore, this composition has the particular advantage that appropriate selection of the photosensitizer allows the spectral sensitivity of the photoinitiator combination package to be shifted to any desired wavelength region. Those skilled in the art can select suitable photosensitizers to make the photoinitiator combination package operate in any desired wavelength region.

[0290] Other suitable photoinitiators include camphorquinone, benzophenone, benzophenone derivatives, acetylbenzene, acetylbenzene derivatives, diekoxyacetylbenzene, α-hydroxy ketones, α-amino ketones, 4-acyl-1,3-dioxolane, benzoyl alkyl ethers, and biphenyl ketals, such as biphenyl dimethyl ketal; ketone sulfones, such as 1-[4-[(4-benzoylphenyl)thio]phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]prop-1-one (Esacure® 1001, IGM Resins BV); 3-ketocoumarins, such as those described in EP2909243 and WO2017216699; phenyl oxalates and their derivatives; diphenyl oxalates; and peresters, such as benzophenone tetracarboxylic acid perester, for example, EP 126 541. The aforementioned, acylphosphine photoinitiators (selected from monoacylphosphine oxides, diacylphosphine oxides, triacylphosphine oxides, and polyfunctional monoacyl or diacylphosphine oxides), halomethyltriazine, hexaaryldiimidazole / co-initiator systems, such as a combination of o-chlorohexaphenyldiimidazole and 2-mercaptobenzothiazole, ferrocene compounds or titanocene compounds, such as dicyclopentadienylbis(2,6-difluoro-3-pyrrolithylphenyl)titanium, and O-acyloxime ester photoinitiators.

[0291] Examples of α-hydroxy ketones and α-amino ketones are 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylprop-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methylprop-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropanoyl)benzyl]phenyl}-2-ethylprop-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropanoyl)phenoxy]phenyl}-2-methylprop-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinylprop-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)but-1-one, and 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]but-1-one.

[0292] Examples of O-acyl oxime photoinitiators are 1,2-octanedione, 1-[4-(phenylthio)phenyl]-2-(O-benzoyl oxime), acetone 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]1-(O-acetyl oxime), or those described in GB 2339571.

[0293] Examples of acylphosphine photoinitiators include, but are not limited to, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-(2,4-dipentoxyphenyl), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoyl)phenylphosphine, phenyl(2,4,6-trimethylbenzoyl)phosphine, and glycerol ethoxylated triester (Omnipol® from IGMresins BV's TP).

[0294] Examples of photoinitiators based on halomethyltriazine are 2-[2-(4-methoxy-phenyl)-vinyl]-4,6-bis-trichloromethyl[1,3,5]triazine, 2-(4-methoxy-phenyl)-4,6-bis-trichloromethyl[1,3,5]triazine, 2-(3,4-dimethoxyphenyl)-4,6-bis-trichloromethyl[1,3,5]triazine, and 2-methyl-4,6-bis-trichloromethyl[1,3,5]triazine.

[0295] When the photopolymerizable compositions according to the invention are used in a mixed system (in this sense, a mixture of a free radical and a cationic curing system), a cationic photoinitiator can also be used as a further photoinitiator. Examples of suitable cationic photoinitiators are aromatic sulfonium, phosphonium, or iodonium salts, as described, for example, in US 4,950,581, or cyclopentadienyl aromatic-iron(II) complex salts, such as (η... 6 -isopropylbenzene)(η 5 (-Cyclopentadienyl)ferric(II)hexafluorophosphate or oxime-based photolatent acids, as described, for example, in GB 2 348 644, US 4,450,598, US 4,136,055, WO 00 / 10972 and WO 00 / 26219.

[0296] Any pigment known to those skilled in the art can be used in photopolymerizable compositions.

[0297] Inorganic and organic pigments may be used depending on the intended use. These additives are well known to those skilled in the art; some examples are carbon black, iron oxide, such as iron oxide yellow, iron oxide red, chrome yellow, chrome green, nickel titanium yellow, ultramarine blue, cobalt blue, bismuth vanadate, cadmium yellow, and cadmium red. Examples of organic pigments are monoazo or diazo pigments and their metal complexes, phthalocyanine pigments, polycyclic pigments such as perylene, anthraquinone, thioindole, quinacridone, or triphenylmethane pigments, and diketone-pyrrole-pyrrole, isoindole-ketone (e.g., tetrachloroisoindole-ketone), isoindole-ketone, dioxazine, benzimidazolone, and quinophthalone pigments. These pigments may be used alone or in blends in formulations.

[0299] When the olefinically unsaturated, free-radical polymerizable compound is a liquid or viscous substance, the addition of a binder is particularly advantageous. The choice of binder is based on the application and desired properties, such as developability in aqueous and organic solvent systems, adhesion to substrates, and oxygen sensitivity. Suitable adhesives are, for example, polymers with a weight-average molecular weight (Mw) of about 5,000 Da to 2,000,000 Da, preferably 10,000 Da to 1,000,000 Da. Illustrative examples include: homopolymers and copolymers of acrylates and methacrylates, such as methyl methacrylate / ethyl methacrylate / methacrylate copolymers, poly(alkyl methacrylate), poly(alkyl acrylate); cellulose esters and ethers, such as cellulose acetate, cellulose acetate butyrate, methyl cellulose, ethyl cellulose, polyvinyl butyral, polyvinyl formal, cyclized rubber, polyethers, such as polyethylene oxide, polypropylene oxide, polytetrahydrofuran, polystyrene, polycarbonate, polyurethane, chlorinated polyolefins, such as polyvinyl chloride, vinyl chloride / vinylidene chloride copolymers, copolymers of vinylidene chloride with acrylonitrile, methyl methacrylate and vinyl acetate, polyvinyl acetate, ethylene / vinyl acetate copolymers, polymers, such as polycaprolactam and poly(hexamethylenediamine adipamide), polyesters, such as poly(ethylene glycol terephthalate) and poly(hexamethylene glycol succinate).

[0300] Suitable examples of co-initiators (also known as promoters) are alcohols, thiols, thioethers, amines or ethers, disulfides and phosphines having available hydrogen atoms bonded to carbon atoms adjacent to heteroatoms, such as those described in EP 438 123 and GB 2 180 358. Suitable examples of amine promoters / co-initiators include, but are not limited to, aliphatic, alicyclic, aromatic, aryl-aliphatic, heterocyclic, oligomeric or polymeric amines. They can be primary, secondary or tertiary amines, such as butylamine, dibutylamine, tributylamine, cyclohexylamine, benzyldimethylamine, dicyclohexylamine, N-phenylglycine, triethylamine, phenyldiethanolamine, triethanolamine, piperidine, piperazine, morpholine, pyridine, quinoline, esters of dimethylaminobenzoic acid, Michler's ketone (4,4'-bis(dimethylaminobenzophenone)) and its derivatives. Amine-modified acrylate compounds can be used as amine promoters / co-initiators; examples of such amine-modified acrylates include acrylates modified by reaction with primary or secondary amines, as described in US 3,844,916, EP 280222, US 5,482,649, or US 5,734,002. Polyfunctional amines and polymeric amine derivatives are also suitable as co-initiators; some examples are Omnipol® ASA from IGM Resins B.V., Genopol® AB-2 from Rahn AG, Speedcure® 7040 from Lambson Limited, or those described in US2013 / 0012611.

[0301] The choice of additives depends on the application area under discussion and the properties required for that application. Typical additives include thermal initiators, stabilizers, light stabilizers, fillers, colorants, antistatic agents, wetting agents, flow improvers, and adhesive enhancers.

[0302] For example, especially in the case of a coloring composition, the composition may also contain a thermal initiator as an additional additive, a compound that forms a free radical upon heating, such as an azo compound, like 2,2'-azobis(4-methoxy-2,4-dimethylpentanonitrile), triazine, diazosulfide, pentaazadiene, or a peroxide compound, such as hydroperoxide or peroxycarbonate, such as tert-butyl hydroperoxide, as described, for example, in EP 245 639.

[0303] Suitable stabilizers include, for example, heat inhibitors such as hydroquinone, hydroquinone derivatives, p-methoxyphenol, β-naphthol, or sterically hindered phenols such as 2,6-bis(tert-butyl)-p-cresol, which prevent premature polymerization. To improve dark storage stability, copper naphthate, copper stearate, or copper octanoate, phosphorus compounds such as triphenylphosphine, tributylphosphine, triethyl phosphite, triphenyl phosphite, or tribenzyl phosphite, quaternary ammonium compounds such as tetramethylammonium chloride or trimethylbenzylammonium chloride, or hydroxylamine derivatives such as N,N-diethylhydroxylamine can be used. To remove atmospheric oxygen during polymerization, paraffin or similar waxes, which are insoluble in the polymer, migrate to the surface at the start of polymerization, forming a transparent surface layer that prevents air ingress.

[0304] Light stabilizers, such as UV absorbers, can also be added, including hydroxyphenylbenzotriazole, hydroxyphenyl benzophenone, oxalamide, or hydroxyphenyl-S-triazine types. These components can be used alone or in mixtures, with or without sterically hindered amines (HALS).

[0305] All fallback positions and preferred embodiments of the photoinitiator combination package described above or below are applicable to photopolymerizable compositions according to this aspect, with necessary modifications to the details.

[0306] method

[0307] In a third aspect, the present invention relates to a method for use in photocurable photopolymerizable compositions, coatings, adhesives, and inks, said method comprising the following steps in a given sequence:

[0308] a) Coating or printing the photopolymerizable composition according to the second aspect onto a substrate, and

[0309] b) Photopolymerize the coated or printed composition on the substrate using a light source.

[0310] Preferably, the light source operates in the near-UV or visible light range of the EM spectrum.

[0311] All alternative locations and preferred embodiments of the photoinitiator combination packages and photopolymerizable compositions described above or below, with necessary modifications to the details, are applicable to methods for photocuring photopolymerizable compositions, coatings, adhesives, and inks according to this aspect.

[0312] use

[0313] In a final aspect, the present invention relates to the use of the photoinitiator combination package according to the first aspect in the production of printing inks, screen printing inks, gravure printing inks, solder resists, etched offset inks, flexographic printing inks, gravure printing inks, inkjet inks, resist materials, insulators, encapsulants, image recording materials, solder resists, passivation layers, protective coatings, 3D printed objects and molds, holographic applications, fiber optic coatings, waveguides and lenses, overprint varnishes, and coatings for wood, vinyl, metal, and plastics.

[0314] All alternative locations and preferred embodiments of the photoinitiator combination package described above or below are applicable to the use of this aspect after necessary modifications to the details.

[0315] Example

[0316] A. Measurement Method

[0317] Through-cure measurement: The complete cure test measures the full curing of the ink at a defined rate and is checked by the "thumb torsion pressure test". The evaluation is as follows: The ink is homogenized at 50°C for 1 hour using a mechanical stirrer and applied to white cardboard at a thickness between 1 and 1.5 micrometers using an IGT repro-tester device.

[0318] The results of the curing measurement can be expressed as the maximum velocity (m / min) that leaves no trace on the surface (where a higher velocity corresponds to higher reactivity) or the minimum light dose (mJ / cm) that leaves no trace on the surface. 2 (Where lower light corresponds to higher reactivity).

[0319] Surface testing: Surface testing measures the complete curing of the ink surface by the number of passes under a lamp at 100 m / min (at a given power), and is checked by pressing a thumb against the surface. If no mark is left, the surface is fully cured. The fewer passes required, the better the surface curing.

[0320] viscous

[0321] After conditioning the sample at 20°C for at least 24 hours, the viscosity was measured using a Brookfield RV DV-I+ viscometer. The rotor and rpm were selected from the instrument's display (the values ​​reported below were measured at 20 rpm), and the measurement was initiated. The viscosity value was recorded once the viscosity stabilized. Lower values ​​correspond to lower viscosity fluids. As those skilled in the art will know, different viscosity ranges require different rotors; CE5 of this application was measured using rotor 6, and IE1 of this application was measured using rotor 5. These differences in rotor size are factored into the calculation of the final Brookfield viscosity value, therefore the final value is rotor-independent.

[0322] B. Experimental

[0323] 1. Materials used

[0324] The following commercially available compounds are used to prepare the reference photoinitiator kit, the photoinitiator kit of this invention, and the comparative photoinitiator kit:

[0325] PI-1: Bis(2,4,6-trimethylbenzoyl)octylphosphine oxide, prepared as in US 5534559 A.

[0326] PI-2: Ethyl(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, CAS#: 84434-11-7, is commercially available from IGM Group BV(NL) as Omnirad TPO-L.

[0327] PI-3: Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, CAS#: 162881-26-7, available as Omnirad 819 from IGM Group BV(NL).

[0328] S: 7-Diethylamino-4-methylcoumarin, CAS#: 91-44-1, available as coumarin 1 from MerckKGaA(DE).

[0329] 2. Formulation (Photoinitiator Combination Package)

[0330] Various photoinitiator combinations of the present invention and comparisons were produced according to the formulations in Table 1:

[0331] Table 1 Formulation of Photoinitiator Combination Pack

[0332]

[0333] Photoinitiator combination packages were prepared by combining photoinitiators and sensitizers (if present) at concentrations shown in Table 1 at room temperature. The formulations were stirred at 60°C for 2 hours.

[0334] CE1 is a highly viscous liquid at room temperature.

[0335] CE2 is a liquid at room temperature.

[0336] CE3 is a solid at room temperature.

[0337] CE4 is a liquid blend at room temperature.

[0338] CE5 is a liquid blend at room temperature with a viscosity of 19400 cP.

[0339] IE1 is a liquid blend at room temperature with a viscosity of 8120 cP.

[0340] 3. Evaluation of general curing and surface curing

[0341] Use the following lamps in Tables 2a to 2d:

[0342] Lamp 1: UV LED lamp with a wavelength of 395nm and an intensity of 16W / cm². 2 .

[0343] Lamp 2: UV LED lamp with a wavelength of 395nm and an intensity of 8W / cm². 2 .

[0344] Lamp 3: UV LED lamp with a wavelength of 395nm and an intensity of 4W / cm². 2 .

[0345] Lamp 4: UV LED lamp with a wavelength of 385nm and an intensity of 16W / cm². 2 .

[0346] Lamp 5: UV LED lamp with a wavelength of 385nm and an intensity of 8W / cm². 2 .

[0347] Lamp 6: UV LED lamp with a wavelength of 365 nm and an intensity of 16 W / cm². 2 .

[0348] Lamp 7: UV LED lamp with a wavelength of 365 nm and an intensity of 8 W / cm². 2 .

[0349] Lamp 8: UV LED lamp with a wavelength of 365 nm and an intensity of 4 W / cm². 2 .

[0350] The photoinitiator assemblies of the present invention were evaluated and their curing performance was compared. The relevant photoinitiator assemblies were added to flexographic inks at a rate of 5 wt%, and the resulting compositions were photocured using different light sources (the values ​​in Table 2a correspond to the maximum curing speed in m / min). Data were measured using black flexographic ink as presented for lamps 1B and 7B, and using cyan flexographic ink as presented for lamps 3C and 8C.

[0351] Table 2a: Comparison of the performance of the photoinitiator combination pack and the photoinitiator combination pack of the present invention in the curing of flexographic inks.

[0352]

[0353] <10 indicates that no full curing was measured, while >100 indicates that the surface is over-cured, meaning the maximum speed will be above 100 m / min; however, the maximum belt speed is 100 m / min, so higher belt speeds cannot be tested.

[0354] As can be seen from the data in Table 2a, the two photoinitiator combinations (CE5 and IE1) containing sensitizers significantly more effectively achieve through-curing of both black and cyan flexographic inks. In this embodiment, IE1 offers significant advantages in terms of ease of handling and incorporation into formulations due to its lower viscosity.

[0355] The performance of the photoinitiator combination of the present invention and a comparative photoinitiator combination for offset printing inks was also evaluated.

[0356] The data labeled "Lamp 1a, 4a, and 6a" represent surface curing tests conducted using lamps 1, 3, and 5, respectively, according to the surface curing procedure given in the test method. The values ​​given in the table correspond to the minimum number of passes required to achieve a fully cured surface. The fewer passes required, the better the curing ability of the photoinitiator package.

[0357] The data labeled "Lamp 1b, 2b, 4b, 5b, and 6b" represent through-curing tests using lamps 1, 2, 4, 5, and 6, respectively, performed according to the through-curing procedure given in the test method. The values ​​given in the table correspond to the maximum through-curing speed in m / min. Higher speeds indicate better curing ability of the photoinitiator assembly.

[0358] Table 2b: Comparison of the performance of the photoinitiator combination pack and the photoinitiator combination pack of the present invention in the general curing and surface curing of yellow offset printing inks.

[0359]

[0360] Table 2c: Comparison of the performance of the photoinitiator combination pack and the photoinitiator combination pack of the present invention in the general curing and surface curing of magenta offset printing ink.

[0361]

[0362] Table 2d: Comparison of the performance of the photoinitiator combination pack and the photoinitiator combination pack of the present invention in the general curing and surface curing of cyan offset printing ink.

[0363]

[0364] As can be seen from Tables 2b to 2d, compared with CE3 and CE5, the ink IE1 of the present invention has an excellent balance between surface curing and through curing.

Claims

1. A photoinitiator assembly package, comprising, more preferably, the following: a) One or more diacylphosphine oxide photoinitiators, each having a structure according to formula (I): (I) Each instance of R is independently selected from C1-C4 alkyl groups; X is selected from direct single bonds, O, S, NR. 3 -CH2CO2- and -CH2CH2CO2-; Where R 1 Selected from C1-C 40 Alkyl groups and C2-C groups separated by one or more O or C3-C8 cycloalkyl groups. 40 Alkyl, wherein the C1-C 40 Alkyl groups or C2-C segments spaced apart 40 Alkyl groups may be unsubstituted or replaced by one or more groups selected from OH and R. 2 Substitution of groups; Where R 2 yes ; Where R 3 Selected from hydrogen, (CO)R 4 , phenyl, C1-C 12 Alkyl group, C2-C separated by one or more O atoms 12 Alkyl, unsubstituted or C3-C4 substituted with one or more C1-C4 alkyl, C1-C4 alkoxy, OH, or NCO-substituted C3-C 12 cycloalkyl, wherein the C1-C 12 Alkyl groups or C2-C segments spaced apart 12 Alkyl groups are either unsubstituted or substituted with one or more C3-C7 cycloalkyl groups, OH, or NCO; and Where R 4 Selected from C1-C 12 Alkyl groups or C2-C groups separated by one or more O atoms 12 Alkyl, wherein the C1-C 12 Alkyl groups or C2-C segments spaced apart 12 The alkyl group is unsubstituted or substituted with one or more C3-C7 cycloalkyl groups, OH, NCO, or a phenyl group substituted with NCO; C3-C 12 Cycloalkyl; C2-C alkyl groups that are unsubstituted or substituted with one or more C1-C4 alkyl groups, OH groups, or C1-C4 alkoxy groups. 10 Alkenyl; unsubstituted or C1-C 12 Alkyl, C1-C 12 Alkoxy, NCO, or C1-C substituted with NCO 12 Alkyl-substituted C6-C 14 Aryl; b) One or more acylphosphine oxide photoinitiators having a structure not according to formula (I); c) One or more optical brighteners / sensitizers; and d) Optionally one or more amines, The photoinitiator combination package is a blend that is liquid at 25°C and standard pressure.

2. The photoinitiator package according to claim 1, wherein each instance of R is Me.

3. The photoinitiator combination according to claim 1 or claim 2, wherein X is selected from direct single bond, O, -CH2CO2- and -CH2CH2CO2-, more preferably selected from direct single bond, -CH2CO2- and -CH2CH2CO2-, and most preferably direct single bond.

4. The photoinitiator package according to any one of the preceding claims, wherein R 1 Selected from C1-C 20 Alkyl group, -(CH2CH2O-) n CH3 and -(CH2CH2O-) n H, where n is an integer in the range of 1 to 20, more preferably R. 1 It is C1-C 20 alkyl.

5. The photoinitiator package according to any one of claims 1 to 4, wherein R 1 It has the structure according to formula (II): (II) Each instance of M is independently selected from (CH2CH2O) and (CH2CH(CH3)O); each instance of Y is independently selected from hydrogen and C1-C4 alkyl groups; Each instance of Z has the structure CH2(M) 1 ) c R 2 ; where M 1 Each instance is independently selected from (OCH2CH2) and (OCH(CH3)CH2); Where a is an integer in the range of 0 to 15; Where b is an integer in the range of 0 to 6; Each instance of c is an integer in the range 0 to 15; Where m is an integer in the range of 0 to 2; and Each instance of X is independently selected from -CH2CO2- and -CH2CH2CO2-.

6. The photoinitiator package according to any one of the preceding claims, wherein at least one of the one or more optical brighteners / sensitizers has a structure according to formula (III): (III) Where R 3a Selected from hydrogen, C1-C 10 Alkyl, C6-C 14 Aryl and C6-C 14 Mixed aromatics, R 4a Selected from hydrogen, C1-C 10 Alkyl and OR 1a The C1-C 10 Alkyl groups can be substituted with one or more fluorine atoms, and R 5a To R 8a Each of them is independently selected from hydrogen, halogen, C1-C 10 Alkyl, OR 1a and NR 2a 2; Where R 1a Each instance is independently selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl, and R 2a Each instance is independently selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl, wherein R 1a To R 8a Each instance can optionally be associated with R 1a To R 8a One or more further instances are combined to form one or more 5- or 6-membered rings.

7. The photoinitiator package according to any one of the preceding claims, wherein at least one of the one or more optical brighteners / sensitizers has a structure according to formula (IV): (IV) Where R 1b To R 4b Each of them is independently selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl, wherein R 1b and R 2b They can combine to form 6-membered saturated or unsaturated rings, which can be selected from hydrogen, C1-C... 10 Alkyl and C6-C 14 One or more substituents of the aryl group are substituted, and wherein R 3b and R 4b They can combine to form a 6-membered ring, which can be selected from hydrogen, C1-C 10 Alkyl and C6-C 14 One or more substituents of the aryl group are substituted; and Where A represents any of the following connecting groups represented by formulas (V) to (IX): (V) (WE) (VII) (VIII) (IX) Each of them This indicates the bond position of A in each formula.

8. The photoinitiator package according to claim 7, wherein at least one of the one or more optical brightener sensitizers has a structure according to formula (X): (X) Where R 1c To R 8c Each of them is independently selected from hydrogen, C1-C 10 Alkyl and C6-C 14 Aryl.

9. A photoinitiator package according to any one of the preceding claims, wherein one or more further acylphosphine oxide photoinitiators having a structure other than that of formula (I) comprises one or more monoacylphosphine photoinitiators and one or more diacylphosphine oxide photoinitiators having a structure other than that of formula (I).

10. The photoinitiator package according to any one of the preceding claims, wherein the photoinitiator package comprises, more preferably, the following: a) One or more bisacylphosphine oxide photoinitiators having the structure according to formula (I) in an amount ranging from 15 to 40% by weight, more preferably from 18 to 35% by weight, and most preferably from 19 to 30% by weight, relative to the total weight of the photoinitiator combination package. b) One or more of a further acylphosphine oxide photoinitiator having a structure not according to formula (I) in an amount ranging from 30 to 75% by weight, more preferably from 40 to 70% by weight, and most preferably from 50 to 60% by weight, relative to the total weight of the photoinitiator combination package. c) One or more optical brightener sensitizers in an amount ranging from 5 to 30% by weight, more preferably from 10 to 25% by weight, and most preferably from 15 to 22% by weight, relative to the total weight of the photoinitiator combination package; and d) Optionally, one or more amines in an amount ranging from 1 to 30% by weight, more preferably from 3 to 25% by weight, and most preferably from 5 to 20% by weight, relative to the total weight of the photoinitiator assembly.

11. A photopolymerizable composition comprising: a) One or more olefinically unsaturated compounds that are free radical polymerizable; b) A photoinitiator combination package according to any one of claims 1 to 10.

12. The photopolymerizable composition according to claim 11, wherein the photopolymerizable composition comprises: a) One or more olefinically unsaturated free radical polymerizable compounds in an amount ranging from 30 to 99.0% by weight, more preferably from 50 to 95.0% by weight, and most preferably from 70 to 90% by weight, relative to the total weight of the photopolymerizable composition; b) A photoinitiator package according to any one of claims 1 to 10, in an amount ranging from 0.5% to 50% by weight, more preferably from 0.8% to 40% by weight, and most preferably from 1.0% to 30% by weight, relative to the total weight of the photopolymerizable composition.

13. The photopolymerizable composition according to claim 11 or claim 12, wherein the photopolymerizable composition further comprises one or more of the following components: c) One or more further photoinitiators, one or more photosensitizers and / or one or more co-initiators in an amount ranging from 0.5 to 30% by weight, more preferably from 0.8 to 20% by weight, and most preferably from 1.0 to 15% by weight; d) One or more pigments in an amount ranging from 0.1 to 30% by weight, more preferably from 1.0 to 25% by weight, and most preferably from 10 to 20% by weight, relative to the total weight of the photopolymerizable composition; e) one or more adhesives in an amount ranging from 5.0 to 60% by weight, more preferably from 8.0 to 50% by weight, and most preferably from 10 to 40% by weight, relative to the total weight of the photopolymerizable composition; and f) One or more additives in an amount ranging from 0.01 to 10% by weight, more preferably from 0.01 to 8.0% by weight, and most preferably from 0.01 to 5.0% by weight, relative to the total weight of the photopolymerizable composition.

14. A method for use in photocurable photopolymerizable compositions, coatings, adhesives, and inks, said method comprising the following steps in a given sequence: a) Coating or printing the photopolymerizable composition according to any one of claims 11 to 13 onto a substrate, and b) Photopolymerize the coated or printed composition on the substrate using a light source.

15. Use of the photoinitiator combination package according to any one of claims 1 to 10 in the production of printing inks, screen printing inks, gravure printing inks, solder resists, etched offset inks, flexographic printing inks, gravure printing inks, inkjet inks, resist materials, insulators, encapsulants, image recording materials, solder resists, passivation layers, protective coatings, 3D printed objects and molds, holographic applications, fiber optic coatings, waveguides and lenses, overprint varnishes, and coatings for wood, vinyl, metals, and plastics.

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