JPH0743536B2 - Photosensitive composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel photosensitive composition containing a compound capable of generating a free radical by light. More specifically, it relates to a photosensitive composition containing a novel water-soluble photosensitive s-triazine compound.

[Conventional technology]

Compounds that decompose to form free radicals when exposed to light (free radical generators) are well known in the field of graphic arts. They are widely used as photoinitiators in photopolymerizable compositions, photoactivators in free radical photographic compositions and as photoinitiators of reactions catalyzed by photogenerated acids. Such free radical generators are used to make a variety of light-sensitive materials useful in printing, reproduction, reproduction and other imaging systems.

Organohalogen compounds are photolyzed to give halogen free radicals such as chlorine and bromine free radicals. These halogen free radicals are good hydrogen-abstracting agents and produce acids in the presence of hydrogen donors. Regarding their application to the photopolymerization process and free radical photographic process, J. Coser's "Light Sensitive Systems" J. Willie & Sons (New York 1965) [J. Kosar's "Light Sensitive"
Systeme "J. Wiley & Sons (New York 1965)] 180-181
Pp. 361-370.

Carbon tetrabromide, iodoform, tribromoacetophenone, and the like have been representative examples of compounds that generate a halogen free radical by the action of light of this kind, and have been widely used. However, these free radical generators have the disadvantage that they decompose only with light in a fairly limited wavelength range. In other words, it was more sensitive to the ultraviolet region of the short wave than the dominant wavelength of the light source normally used. Therefore, these compounds are inferior in their ability to generate free radicals because they do not have the ability to effectively utilize light in the near-ultraviolet to visible region emitted by the light source.

In order to improve this drawback, a halogen free radical generator having a photosensitive wavelength range from near ultraviolet to visible light has been proposed. For example, U.S. Pat.Nos. 3,954,475, 3,987,037 and
There is a halomethyl-s-triazine compound group described in 4,189,323. Although these compounds have a photosensitive wavelength range from near-ultraviolet to visible light, the irradiated light is not used effectively and the sensitivity of photolysis is relatively low.

Further, since these triazine compounds are hardly soluble or insoluble in water, they cannot be uniformly mixed with a water-based photosensitive coating composition using water as a solvent, and thus the photosensitive composition is sufficiently sensitive. There was a drawback that it did not come out.

[Problems to be solved by the invention]

Therefore, an object of the present invention is to provide a photosensitive composition containing a free radical generator having high photodecomposition sensitivity and having high sensitivity.

Another object of the present invention is to provide a photosensitive composition containing a water-soluble free radical generator which can be uniformly mixed with an aqueous photosensitive coating composition.

[Means for solving problems]

As a result of various studies to achieve the above objects, the present inventors have
It has been found that the above problems can be solved by using a novel water-soluble s-triazine compound represented by the general formula [I]. The compound represented by the general formula [I] can be uniformly mixed with an aqueous photosensitive coating composition using water as a solvent.

In the general formula [I], R ₁ is a carboxylate group, a sulfonate group, a carboxylamide group, a sulfonamide group, an N-hydroxycarboxylamide group, or an alkyl group having these groups, a substituted alkyl group, an alkoxy group or a substituted alkoxy group. Group, aryl group, substituted aryl group, aryloxy group,
It represents a substituted aryloxy group or a substituted amino group.

R ₂ and R ₃ may be the same or different from each other, and are a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, an aryloxy group, a substituted aryloxy group,
It represents an alkoxy group, a substituted alkoxy group, an acyl group, a substituted acyl group, a halogen atom, or a group represented by R ₁ .

However, when R ₁ is a carboxylate group, a sulfonate group, a carboxylamide group, a sulfonamide group or a substituted amino group having an N-hydroxycarboxylamide group, R ₂ or R ₃ is a carboxylate group, a sulfonate group, Carboxylamide group, sulfonamide group or N-
It is a hydroxycarboxylamide group.

X and Y may be the same as or different from each other and represent a chlorine atom or a bromine atom.

m and n represent 0, 1 or 2.

Hereinafter, the present invention will be described in more detail.

In the general formula [I], the alkyl group represented by R ₁ to R ₃ has 1 to 6 carbon atoms such as methyl group, ethyl group and isopropyl group.
Up to 1 to 4, alkoxy groups such as methoxy and ethoxy groups having 1 to 4 carbon atoms, aryl groups such as phenyl groups and 6 to 14 carbon atoms, aryloxy groups such as phenoxy groups 6 to 14, acyl groups such as acetyl and propionyl groups having 2 to 10 carbon atoms, substituted amino groups such as N-methylamino, N, N-diethylamino and N, N-diphenylamino groups The alkylamino group and the arylamino group of the numbers 1 to 16 can be used.

Examples of the substituents of the substituted alkyl group, the substituted aryl group, the substituted alkoxy group, the substituted acyl group, and the substituted aryloxy group of R ₁ to R ₃ include an aryl group such as a phenyl group and a halogen atom such as a chlorine atom; a methoxy group. An alkoxy group such as an ethoxy group; a carboxyl group; a carboalkoxy group such as a carbomethoxy group or a carboethoxy group; a carboaryloxy group; a cyano group; an acyl group such as an acetyl group or a benzoyl group; a nitro group; a dialkylamino group; or General formula: (Here, Z represents a hydrogen atom or an alkyl group or an aryl group. However, the case where Z is a hydrogen atom in the general formula (C) is excluded).

Further, the substituent of the substituted aryl group of R ₁ to R ₃ includes an alkyl group in addition to the above-mentioned substituents.

Examples of compounds (exemplary compounds) useful as a free radical generator used in the present invention are shown below. However, it goes without saying that the present invention is not limited to the following compounds.

The water-soluble free radical generator represented by the general formula (I) is particularly useful when used as a photopolymerization initiator of an aqueous photopolymerizable coating composition.

When the free radical generator represented by formula (I) is used in the photopolymerizable composition, the photopolymerizable composition requires a polymerizable compound having an ethylenically unsaturated bond, a photopolymerization initiator, and It is composed of a binder and, if necessary, a sensitizer, and is particularly useful for a photosensitive layer of a photosensitive printing plate, a photoresist and the like.

The polymerizable compound having an ethylenically unsaturated bond in the photopolymerizable composition of the present invention is a compound having at least one ethylenically unsaturated bond in its chemical structure, which is a monomer, a prepolymer, that is, It has a chemical form such as a dimer, a trimer and other oligomers, a mixture thereof and a copolymer thereof. Examples thereof include unsaturated carboxylic acids and salts thereof, esters of unsaturated carboxylic acids with aliphatic polyhydric alcohol compounds, and amides of unsaturated carboxylic acids with amine compounds.

Specific examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid,
Maleic acid etc.

Salts of unsaturated carboxylic acids include the alkali metal salts of the acids mentioned above, for example the sodium and potassium salts.

Specific examples of the ester of an aliphatic polyhydric alcohol compound and an unsaturated carboxylic acid include acrylic acid ester, ethylene glycol diacrylate, triethylene glycol diacrylate, 1,3-butanediol diacrylate, tetramethylene glycol diacrylate, Propylene glycol diacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, dipentaerythritol dimethacrylate,
There are sorbitol trimethacrylate, sorbitol tetramethacrylate, bis- [p- (3-methacryloxy-2-hydroxypropoxy) phenyl] dimethylmethane, bis- [p- (methacryloxyethoxy) phenyl] dimethylmethane and the like. As itaconic acid esters, ethylene glycol diitaconate, propylene glycol diitaconate, 1,3-butanediol diitaconate, 1,4-butanediol diitaconate, tetramethylene glycol diitaconate, pentaerythritol diitaconate , Sorbitol tetri taconate, etc. Examples of crotonic acid esters include ethylene glycol dicrotonate, tetramethylene glycol dicrotonate, pentaerythritol dicrotonate, and sorbitol tetracrotonate. Examples of the isocrotonic acid ester include ethylene glycol diisocrotonate, pentaerythritol diisocrotonate, and sorbitol tetraisocrotonate. Examples of the maleic acid ester include ethylene glycol dimaleate, triethylene glycol dimaleate, pentaerythritol dimaleate, and sorbitol tetramaleate. Further, a mixture of the above-mentioned esters can also be mentioned.

Specific examples of the amide of an amine compound and an unsaturated carboxylic acid include acrylamide, methylenebis-acrylamide, methylenebis-methacrylamide, 1,6-hexamethylenebis-acrylamide, 1,6-hexamethylenebis-methacrylamide, and diethylenetriaminetris. Examples include acrylamide, xylylene bis acrylamide, and xylylene bis methacrylamide.

As another example, a polyisocyanate compound having two or more isocyanate groups in one molecule, which is described in JP-B-48-41708, is added to the following general formula (II).
A vinyl urethane compound having two or more polymerizable vinyl groups in one molecule, to which a vinyl monomer having a hydroxyl group shown by is added, is exemplified.

CH ₂ ═C (R) COOCH ₂ CH (R ′) OH (II) (wherein R and R ′ represent H or CH ₃ ) Particularly useful as the polymerizable compound having an ethylenically unsaturated bond Those which are soluble in water or alcohol are exemplified by hydroxyethyl acrylate, pentaerythritol triacrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, ( (Meth) acrylic acid calcium salt, (meth) acrylic acid barium salt, dipentaerythritol tetraacrylate, poly (meth) alcohol such as glycerin or trimethylolethane added with ethylene oxide or propylene oxide, and then (meth) acrylated, More than 5 waters per molecule That the low-molecular compound portion (meth) acrylated with group, acrylamide, N- methylol acrylamide,
N-vinylpyrrolidone, diacetone-acrylamide,
There are methylenebisacrylamide and N-methylolacrylamide derivatives described in US Pat. No. 4,540,649.

When the free radical generator represented by formula (I) is used as the photopolymerization initiator in the photopolymerizable composition, the photopolymerizable composition may contain a binder, if necessary.

As the binder in the photopolymerizable composition of the present invention, the compatibility with the polymerizable ethylenically unsaturated compound and the photopolymerization initiator, the preparation of the coating solution of the composition, the coating and drying process of the photosensitive material In all, it is good enough not to cause demixing, as a photosensitive layer or a resist layer, for example, it is possible to perform development processing after image exposure, whether solution development or peeling development, and a robust photosensitive layer or resist layer. It is required to have characteristics such as being able to form a film. Many organic polymers can be used as such a binder. For example, polyamide, polyvinyl ester, polyvinyl acetal, polyvinyl ether, epoxy resin, polyacrylic acid ester, polymethacrylic acid ester, polyester, alkyd resin,
Mention may be made of copolymers of monomers of polyacrylamide, polyvinyl alcohol, polydimethylacrylamide, polyvinylpyrrolidone, polyvinylmethylformamide and homopolymers thereof, and monomers copolymerizable with these monomers. As the other binder, natural substances such as gelatin and cellulose can be used.

Binders particularly useful in the present invention are water-soluble, such as, for example, the above acrylic acid, methacrylic acid copolymer salts,
Specific examples include a sodium salt of a copolymer of methyl methacrylate and methacrylic acid, a sodium salt of a copolymer of benzyl methacrylate and methacrylic acid, a sodium salt of a copolymer of methacrylic acid and allyl methacrylate, acrylonitrile. And a sodium salt of a copolymer of acrylic acid and a sodium salt of a copolymer of styrene and acrylic acid.

Other water-soluble binders useful in the present invention are those having an amide bond, examples of which are copolymers containing dimethylacrylamide, methylacrylamide, vinylpyrrolidone, and other useful water-soluble binders. Examples thereof include polyvinyl alcohol, polyvinyl acetate, and a sulfonate of a styrene copolymer. The photosensitive composition of the present invention may contain various additional substances depending on the intended use and the desired properties.

Examples of these are sensitizers that increase the sensitivity of the free radical generator of the present invention, spectral sensitizers that broaden the spectral sensitivity region of the free radical generator of the present invention, thermal polymerization inhibitors that prevent thermal polymerization of monomers, and hydrogen. Donors, substances that improve the image-forming ability of the image obtained by using the photosensitive composition of the present invention, dyes, colored and colorless pigments, dye-forming agents, indicators and plasticizers.

The photopolymerizable composition of the present invention is used by dissolving the above-mentioned various constituents in a solvent and coating it on a suitable support by a known method. Next, the preferable ratio of the various constituents in this case is expressed in parts by weight relative to 100 parts by weight of the polymerizable compound having an ethylenically unsaturated bond.

The photopolymerizable compositions according to the invention are used in many fields of application, for example for the production of safety glass, varnish coatings and dental fillings which are cured by light or electron beam irradiation, and especially as light-sensitive copying materials in the field of copying. Can be used.

The photopolymerizable composition of the present invention can also be used as a photosensitive layer of a photosensitive lithographic printing plate.

Further, the free radical generator represented by the general formula (I) is used in various image forming systems as a compound that gives a visible image upon exposure in combination with a compound that develops or decolorizes with an acid. An example is the use of a photosensitive resist composition as a printout agent.

Other uses include COC groups or OS that decompose with acid as a photo-epoxy curing agent in combination with an epoxy resin.
It can also be added to a mixture containing a compound having at least one i group and used as a photoacid generator.

The use as a print-out agent for a photosensitive resist composition and as a photo-acid generator mixed with an acid-decomposable compound will be described in more detail below.

When the free radical generator represented by the general formula (I) is used in a photosensitive resist-forming composition, the photosensitive resist composition can obtain a visible image only by exposure under a yellow safety light in an exposure operation. In the process of exposing many printing plates at the same time, it becomes possible to know whether or not the plate given to the platemaker is exposed, for example, when work is interrupted.

Similarly, for example, when exposing one large plate many times as in the so-called plate printing method when making a lithographic printing plate, the operator should immediately check which part has been exposed. You can

A photosensitive resist-forming composition which gives a visible image immediately upon exposure, in which the free-radical-forming agent represented by the general formula (I) can be advantageously used, has as essential components a photosensitive resist-forming compound, a free-radical-forming agent and a color-changing agent. And optionally one or more plasticizers, binders, non-discoloring dyes, pigments, antifoggants, sensitizers for photosensitive resist-forming compounds, etc.

A photosensitive resist-forming compound is a compound whose physical properties such as solubility, tackiness, and adhesion to a substrate change upon exposure, and examples thereof include a photosensitive diazo compound, a photosensitive azide compound, and an ethylenically unsaturated compound. It includes compounds having a bond and compounds that undergo a reaction catalyzed by a photo-generated acid.

Suitable photosensitive diazo compounds include salts of p-diazodiphenylamine, for example, salts of inorganic acids such as zinc chloride double salt and sulfuric acid double salt, or methanesulfonate, paratoluenesulfonate, phenol salt, 1-naphthol-. There are salts of organic acids such as 5-sulfonate. Alternatively, a compound having two or more diazo groups in one molecule such as a condensation product of a salt of p-diazodiphenylamine and formaldehyde is preferable.

A particularly preferred photosensitive diazo compound is a water-soluble diazo compound, and specifically, a salt of p-diazodiphenylamine and methanesulfonic acid or a salt of p-diazodiphenylamine and an inorganic acid can be used.

On the other hand, a photosensitive diazo compound which becomes soluble in alkali upon irradiation with active light can also be used. It is a compound having at least one o-quinonediazide group in one molecule, and a sulfonic acid ester or amide of o-quinonediazide is particularly preferable. Although many such compounds are already known, those particularly useful in the present invention are water-soluble or water-miscible solvents, and specifically, a sulfonic acid amide of o-quinonediazide is used. be able to.

Examples of suitable photosensitive azide compounds include aromatic azide compounds in which an azide group is bonded to an aromatic ring directly or through a carbonyl group or a sulfonyl group. These are those in which the azido group is decomposed by light to produce nitrene, which is insolubilized by various reactions of nitrene. Preferred aromatic azide compounds include azidophenyl,
Compounds containing one or more groups such as azidostyryl azidobenzal, azidobenzoyl and azidocinnamoyl, but particularly useful in the present invention are substituted with sulfonic acid, sulfonate or carboxylic acid, carboxylate Water-soluble or water-miscible solvent, specifically, 4,4'-diazidostilbene-2,2'-disulfonic acid, 4'-azidobenzalacetophenone-2
-Sulfonic acid, 4,4'diazidostilbene-α-carboxylic acid, 4-azidobenzalacetophenone-2-sulfonic acid and metal salts of these sulfonic acids and carboxylic acids such as sodium can be used.

As a compound having a suitable ethylenically unsaturated bond,
It includes a polymer that can be crosslinked by a photodimerization reaction of ethylene bond, and a polymerizable compound that is photopolymerized to give an inactive polymer in the presence of a photopolymerization initiator.

For example, as a polymer having an ethylenically unsaturated bond and insolubilized by photodimerization, There are polyesters, polyamides, and polycarbonates containing. Examples of such a polymer include a photosensitive polymer containing a photosensitive group in the polymer main chain as described in U.S. Pat. Nos. 3,030,208 and 3,707,373, such as p-phenylenediacrylic acid. Photosensitive polyester consisting of diol, US Pat. No. 2,690,96
No. 6, 2,752,372, and No. 2,732,301, photosensitive polymers such as cinnamic acid esters of hydroxyl-containing polymers such as polyvinyl alcohol, starch, cellulose and the like. Etc.

Examples of the polymerizable compound that is photopolymerized to give an inactive polymer include the examples shown as the components of the photopolymerizable composition.

The discoloring agent used for producing a photosensitive resist-forming composition capable of obtaining a visible image only by exposure is a substance which is originally colorless due to the action of the photodecomposition product of the free radical generating agent. There are two types: one that changes to a colored state and one that originally has a unique color changes or decolorizes.

Arylaminos can be mentioned as typical examples of the discoloring agents belonging to the former type. Aryl amines suitable for this purpose include so-called leuco dyes as well as simple aryl amines such as primary and secondary aromatic amines.

In addition, as a color-changing agent which has an inherently unique color and whose color is changed or decolorized by a photolysis product of a free radical-forming agent, diphenylmethane, triphenylmethane-based thiazine, oxazine-based, xanthene-based, Various dyes such as anthraquinone type and iminonaphthoquinone type azomethine type are effectively used.

Particularly useful dyes in the present invention are those soluble in water or water-miscible solvents, such as ethyl violet,
Erythrosin B, crystal violet, methyl violet 2B, Victoria Pure Blue, etc. can be used.

The photosensitive composition of the present invention is used by dissolving the above-mentioned various components during the dissolution and coating it on a suitable support by a known method.

Solvents used when applying the photosensitive composition of the present invention include water, methanol, ethanol, isopropanol, acetonitrile, ethylene dichloride, cyclohexanone, methyl ethyl ketone, methyl cellosolve acetate, monochlorobenzene, toluene, ethyl acetate and the like. Particularly, water or alcohol such as methanol is preferable. You may use these solvent individually or in mixture.

The photosensitive composition of the present invention is suitable as a photosensitive layer of a photosensitive lithographic printing plate. In the case of producing a photosensitive lithographic printing plate, the coating amount is generally suitable as a solid content of 0.1 to 10.0 g / m ² , and particularly preferably 0.5 to 5.0 g / m ² . Suitable supports for the photosensitive lithographic printing plate include a hydrophilized aluminum plate, for example, a silicate-treated aluminum plate, an anodized aluminum plate, a grained aluminum plate, a silicate electrodeposited aluminum plate, and a zinc plate, Examples thereof include a stainless plate, a chrome-treated copper plate, and a hydrophilized plastic film or paper.

When the photosensitive composition of the present invention is used for producing a proof plate for printing, a film for an overhead projector, and a film for a second original drawing, a support suitable for them is a transparent material such as polyethylene terephthalate film or cellulose triacetate film. Films and those obtained by matting the surface of these plastic films chemically or physically can be mentioned.

When the photosensitive composition of the present invention is used for producing a film for a photomask, a suitable support is aluminum,
The polyethylene terephthalate film which vapor-deposited aluminum alloy and chromium, and the polyethylene terephthalate film which provided the coloring layer can be mentioned.

When the composition of the present invention is used as a photoresist, various materials such as a copper plate, a copper plated plate, a stainless plate, a glass plate can be used as a support.

In a photosensitive resist-forming composition in which the free-radical-forming agent represented by the general formula (I) contains various photosensitive resist-forming compounds, the discoloring agent which decomposes and coexists when exposed to light is efficiently used. It's amazing how often it instantly discolors. As a result, a sharp boundary is obtained between the exposed portion and the unexposed portion, and it is recognized as a visible image with rich contrast.

Further, since the free radical generator represented by the general formula (I) is water-soluble, a water-soluble photosensitive resist coating liquid can be prepared.

Further, the free radical generating agent represented by the general formula (I) is a good hydrogen abstracting agent and produces an acid in the presence of a hydrogen donor. Therefore, a photodecomposable photosensitive composition is obtained by coexisting a compound that is decomposed by an acid. Examples of compounds that are decomposed by acids include U.S. Patent Nos. 4,101,323 and 4,247,611.
No. 4,48,957, 4,250,247 or 4,311,78
No. 2 and JP-A No. 60-37549.

Hereinafter, for reference of a method for synthesizing a free radical generating agent used in the present invention, a synthetic method which is not the free radical generating agent used in the present invention but can be applied correspondingly to the synthesis of the free radical generating agent used in the present invention An example will be described, but the present invention is not limited to this.

<Synthesis example> 4- [PN, N-di (sodiumcarboxylmethyl) aminophenyl] -2,6-di (trichloromethyl) -S-
Synthesis of triazine reference compound 4- [PN, N-di (ethoxycarbonylmethyl) aminophenyl] -2,6-di (trichloromethyl) -S-triazine 87.7 g, concentrated hydrochloric acid 220 ml and acetonitrile 880 ml
Was placed in a flask and heated under reflux for 4 hours and a half.

After allowing to cool, the reaction solution was poured into 6 l of water and the precipitated crystals were collected by filtration.
The crystals were washed with water of 1 and air-dried to obtain 76.3 g of crystals.

Dissolve 30.0 g of the obtained crystals in 1500 ml of ethanol and 300 ml of water, add 91.5 ml of 1N sodium hydroxide solution, and adjust the pH of the solution.
After setting to 10.3, the liquid was concentrated and evaporated under reduced pressure to dryness, and 34.8
g crystals were obtained.

Decomposition start temperature 199 ℃. Absorption spectrum in water λmax 403
nm (ε = 2.88 × 10 ⁴ ) Example 1 The following photopolymerizable photosensitive composition was prepared.

Gohsenol GM30 13% aqueous solution 50.0g (Polyvinyl alcohol manufactured by Nippon Gohsei) Methylenebisacrylamide 0.5g Acrylamide 5.0g Free radical generator (Exemplified compound (3)) 0.1g Victoria Pure Blue 0.05g Polyester film It was coated on top and dried. This photosensitive layer is a metal halide lamp (0.5k
w) was imagewise exposed. When the unexposed portion was removed with water, a clear relief image was obtained.

 ─────────────────────────────────────────────────── --- Continued from the front page (56) References JP-A-53-133428 (JP, A) JP-A-62-180359 (JP, A) JP-A-62-254141 (JP, A) JP-A-63- 153542 (JP, A) Japanese Patent Publication 6-93117 (JP, B2)

Claims (1)

[Claims] 1. A photosensitive composition containing a water-soluble and photosensitive s-triazine compound represented by the following general formula (I). In the general formula [I], R ₁ is a carboxylate group, a sulfonate group, a carboxylamide group, a sulfonamide group, an N-hydroxycarboxylamide group or an alkyl group having these groups, a substituted alkyl group, an alkoxy group or a substituted alkoxy group. Group, aryl group, substituted aryl group, aryloxy group,
It represents a substituted aryloxy group or a substituted amino group. R ₂ and R ₃ may be the same or different from each other, a hydrogen atom,
An alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, an aryloxy group, a substituted aryloxy group, an alkoxy group, a substituted alkoxy group, an acyl group, a substituted acyl group, a halogen atom, or a group represented by R _1. Represent. However, when R ₁ is a carboxylate group, a sulfonate group, a carboxylamide group, a sulfonamide group or a substituted amino group having an N-hydroxycarboxylamide group, R ₂ or R ₃ is a carboxylate group, a sulfonate group, Carboxylamide group, sulfonamide group or N-
It is a hydroxycarboxylamide group. X and Y may be the same as or different from each other and represent a chlorine atom or a bromine atom. m and n represent 0, 1 or 2.