Abstract: A method of making a composite part includes the steps of placing a first section of a fibrous pre-form in a mold and infusing the first section of the fibrous pre-form with a resin so as to produce a resin-infused portion and a non-resin-infused portion. Next, the method includes coupling the non-resin-infused portion to a second section of the fibrous pre-form to create a coupled non-resin-infused portion. Then, the coupled non-resin-infused portion is infused with resin to create a second resin-infused portion and a second non-resin-infused portion. These steps are repeated to separately infuse different sections of the part until the part is complete. The corresponding apparatus preferably employs a rigid mold having a shape defining only a portion of the composite part to be made. And, the method is particularly adapted to making both cored and non-cored structures that are large or unconventionally shaped.

Abstract: A method of making a composite part includes the steps of placing a first section of a fibrous pre-form in a mold and infusing the first section of the fibrous pre-form with a resin so as to produce a resin-infused portion and a non-resin-infused portion. Next, the method includes coupling the non-resin-infused portion to a second section of the fibrous pre-form to create a coupled non-resin-infused portion. Then, the coupled non-resin-infused portion is infused with resin to create a second resin-infused portion and a second non-resin-infused portion. These steps are repeated to separately infuse different sections of the part until the part is complete. The corresponding apparatus preferably employs a rigid mold having a shape defining only a portion of the composite part to be made. And, the method is particularly adapted to making both cored and non-cored structures that are large or unconventionally shaped.

Abstract: A process for bonding surfaces together comprises(i) exposing to actinic radiation a layer of a liquid composition containing an epoxide resin, photopolymerizable compound, and a heat-activated curing agent for epoxide resins until the composition solidifies to form a film adhesive while the epoxide resin remains substantially heat-curable,(ii) sandwiching the film adhesive between the surfaces to be bonded, and(iii) then heating the assembly so that the epoxide resin component of the film adhesive is cured.Surfaces which may be so bonded may be metal, glass, ceramic, or wood.

Abstract: Polymerizable compositions comprise(a) a compound containing both(i) at least one acryloyloxy or methacryloyloxy group,(ii) at least one allyl, methallyl, or 1-propenyl group attached directly to a carbon atom which forms part of an aromatic nucleus or to an oxygen atom or an oxycarbonyl group which are in turn directly attached to such a carbon atom,the total of the said groups (i) and (ii) being at least three, and(b) a compound containing at least two mercaptan groups directly attached to aliphatic carbon atoms, in a proportion as to supply at least 0.8 such mercaptan group per allyl, methallyl or 1-propenyl group in (a) but less than 1.0 such mercaptan group in (a) per acryloyl, methacryloyl, allyl, methallyl, or 1-propenyl group.

Abstract: In a three stage process, a layer of a liquid composition containing a compound (A) having in the same molecule at least one (meth)acryloyl group and at least one 2,3-disubstituted maleimido group is exposed to actinic radiation so that the layer solidifies due to photopolymerization of (A) through the (meth)acryloyl group(s), remaining, however, further photocrosslinkable. When desired, the solidified layer is exposed, as through a negative, to a substantially greater amount of actinic radiation, the parts so further exposed becoming more highly photocrosslinked through the disubstituted maleimido group(s) and hence insoluble. An image is produced which can be developed by means of suitable solvents. Examples of (A) include N-(2-(acryloyloxy)ethyl)-2,3-dimethylmaleimide and N-(3-(methacryloyloxy)-2-hydroxypropyl)-2,3-dimethylmaleimide.

Abstract: In a three stage process, a layer of a liquid composition containing a compound (A) having in the same molecule both at least one (meth)acryloyl group and at least one anthryl group is exposed to actinic radiation so that the layer solidifies due to photopolymerization of (A) through the (meth)acryloyl group(s), remaining, however, further photocrosslinkable. When desired, the solidified layer is exposed, as through a negative, to a substantially greater amount of actinic radiation, the parts so further exposed becoming more highly photocrosslinked through the anthryl group(s) and hence insoluble. An image is produced which can be developed by means of suitable solvents. Examples of (A) include 3-(acryloyloxy)-2-hydroxypropyl anthracene-9-carboxylate and its methacryloyl homologue.

Abstract: New aromatic sulfonylsulfoxonium salts are of formula ##STR1## where q is 1 to 4,R denotes an aliphatic, cycloaliphatic, or aromatic group,R.sup.6 denotes H, an alkyl or aralkyl group, or a group --COR.sup.9, --CO--NH--(CO).sub.r --R.sup.10, or --SO.sub.2 --R.sup.11, where r is zero or 1,one, but not both, of R and R.sup.6 denoting an aromatic group,R.sup.7 denotes an alkyl, alkenyl, cycloalkyl, cycloalkylalkyl, or aralkyl group,R.sup.8 has the same meaning as R.sup.7 but may alternatively represent a dialkylamino group or, if R.sup.7 denotes alkyl, it may alternatively represent an arylamino group,R.sup.9, R.sup.10, and R.sup.11 each denote an alkyl, aryl, or aralkyl radical of 1 to 25 carbon atoms,t is 1, 2, or 3, andZ.sup.- denotes a t-valent anion of a protic acid.The salts, e.g., dimethyl-p-toluenesulfonylmethylsufoxonium hexafluorophosphate, are useful as catalysts for the polymerization of cationically polymerizable materials by means of actinic radiation and/or heat.

Abstract: Substances (I) capable of being converted into higher-molecular weight materials under the influence of a cationic catalyst, such as 1,2-epoxides, aminoplasts, vinyl monomers and prepolymers, or phenoplasts, are so converted by exposure to actinic radiation in the presence of an aryl- or aroyl- carbamoylsulfoxonium salt (II) of formula ##STR1## where p is zero or 1,q is 1 to 4,Ar denotes an aromatic group,R.sup.6 denotes --H or group --COR.sup.9 or --CONH(CO).sub.r R.sup.10,R.sup.7 denotes an alkyl, alkenyl, cycloalkyl, cycloalkylalkyl, aryl, or aralkyl group,R.sup.8 has the same meaning as R.sup.7 but may alternatively represent a dialkylamino group or, if R.sup.7 denotes alkyl, it may alternatively represent an arylamino group,R.sup.9 and R.sup.10 each denote a saturated or ethylenically unsaturated radical,r is zero or 1,t is 1, 2, or 3, andZ.sup.t- denotes a t-valent anion of a protic acid.

Abstract: A method for forming an image by a positive resist process comprises:(1) exposing imagewise to actinic radiation a photoresist composition comprising:(a) a film-forming organic material having at least one substituted benzoin group of formula: ##STR1## where R.sup.1 denotes a hydrogen atom, an alkyl, cycloalkyl, cycloalkylalkyl, or aralkyl group or a group --(CH.sub.2).sub.b X; R.sup.2 denotes a hydrogen atom or an alkyl, cycloalkyl, cycloalkylalkyl, aryl or aralkyl group; R.sup.3 denotes a halogen atom or an alkyl, alkoxy, cycloalkyl, cycloalkylalkyl or phenyl group; X denotes a halogen atom, an alkoxy group, a phenoxy group, a group --COOR.sup.4 or a group --OOCR.sup.4, where R.sup.

Abstract: Substances (I) capable of being converted into higher-molecular weight materials under the influence of a cationic catalyst, such as 1,2-epoxides, aminoplasts, vinyl monomers or prepolymers, or phenoplasts, are so converted by exposure to actinic radiation in the presence of a sulphoxonium salt (II) of formula ##STR1## where P denotes zero or 1,R.sup.6 denotes an arylene or aralkylene group,R.sup.7 denotes --H or a group of formula ##STR2## R.sup.8 denotes an alkyl, alkenyl, cycloalkyl, cycloalkylalkyl, aryl, or aralkyl group,R.sup.9 has the same meaning as R.sup.8 but may alternatively represent a dialkylamino group or, if R.sup.8 represents an alkyl group, R.sup.9 may represent an arylamino group,R.sup.10 and R.sup.11 each independently have the same meaning as R.sup.8 but may also each denote --H,r represents 1, 2, or 3,Z.sup.r- denotes an r-valent anion of a protic acid, and q denotes zero when p denotes zero, or zero or 1 when p denotes 1.

Abstract: Polymerizable compositions comprise(a) a compound containing in the same molecule both at least one phenolic hydroxyl group and at least two groups chosen from allyl, methallyl, and 1-propenyl groups, e.g., 2,2-bis(3-allyl-4-hydroxyphenyl)propane or bis(3-(1-propenyl)-4-hydroxyphenyl)methane,(b) a compound containing at least two mercaptan groups per molecule, e.g., pentaerythritol tetrathioglycollate, and(c) a heat-activated crosslinking agent for phenol-aldehyde novolac resins.The compositions are caused to polymerize by the action of irradiation of free-radical catalysts. The polymers so obtained, containing more than one phenolic hydroxyl group, can be subsequently crosslinked in situ by heating. The compositions are useful in various two-stage operations, such as the production of multilayer printed circuits.Polymerizable compositions may also comprise(d) a compound as (a) but containing at least two phenolic hydroxyl groups,(e) a compound containing more than two mercaptan groups per molecule.

Abstract: Substances (I) capable of being converted into higher-molecular weight materials under the influence of a cationic catalyst, such as 1,2-epoxides, aminoplasts, vinyl monomers or prepolymers, or phenoplasts, are so converted by exposure to actinic irradiation or by heating in the presence of an aryloxysulfoxonium salt of formula ##STR1## where either R.sup.6 and R.sup.7 separately denote lower alkyl (optionally substituted by halogen and interrupted in the chain by --O-- or --SO.sub.2 --), or an aryl or aryloxy group, or R.sup.6 and R.sup.7 together denote a divalent group forming with the S atom a heterocyclic radical; R.sup.8 denotes an aryl group; M denotes an atom of a metal or metalloid; X denotes a halogen atom; and n is 4, 5, or 6, for instance,p-chlorophenoxy-p-tolyl-p-phenoxysulfoxonium hexafluorophosphate and 1-phenoxy-1-oxidotetrahydrothiophenium tetrafluorborate.

Abstract: Diglycidyl unsaturated ketones of formula ##STR1## e.g., 1,5-bis(p-glycidyloxyphenyl)-1,4-pentadien-3-one, are prepared by condensing one molar equivalent of a ketone of formulaR.sup.1 -CH.sub.2 COCH.sub.2 -R.sup.2with two molar equivalents of an o- or p- glycidyloxybenzaldehyde of formula ##STR2## in the presence of a basic catalyst, where R represents an alkyl or alkoxy group of 1 to 5 carbon atoms, an alkenyl group of 2 to 5 carbon atoms, a carbalkoxy group of 2 to 10 carbon atoms, a cycloalkyl group of 5 to 8 carbon atoms, a halogen atom, a nitro group, or a carboxyl, sulfonic acid, or phosphonic acid group in the form of a salt,m represents zero or 1 to 4, andR.sup.1 and R.sup.2 each represent a hydrogen atom or an alkyl group of 1 to 5 carbon atoms, or together form a straight chain or branched alkylene group of 2 to 6 carbon atoms.The products are useful as photopolymerizable resins.

Abstract: Fibrous-reinforced composites, such as prepregs and sheet moulding compounds, are made with a thermosettable unsaturated polyimide resin, a photopolymerizable compound, and a heat-activated curing agent for the resin. Fibers may be impregnated with a liquid mixture of the resin and the photopolymerizable compound, and irradiated to cause the mixture to solidify through photopolymerization. The product, when desired, e.g., after stacking to form a multilayer laminate or after shaping, is heated to cure the resin. Alternatively, the liquid mixture is irradiated to form a solid film, into which the fibers are pressed, and, when required, the assembly is heated to cure the resin. The resins employed contain at least two maleimide, citraconimide, or itaconimide groups linked through nitrogen atoms thereof to carbon atoms.

Abstract: Fibrous-reinforced composites, such as prepregs and sheet moulding compounds, are made with a thermosettable cyanato resin, a photopolymerizable compound, and, if required, a heat-activated accelerator for heat-curing the resin. Fibers may be impregnated with a liquid mixture of the resin and the photopolymerizable compound, and irradiated to cause the mixture to solidify through photopolymerization. The product, when desired, e.g., after stacking to form a multilayer laminate, or after shaping, is heated to cure the resin. Alternatively, the liquid mixture is irradiated to form a solid film into which the fibers are pressed, and then, when required, the assembly is heated to cure the resin. The cyanato resins employed are of formula ##STR1## where R is an aliphatic, cycloaliphatic, or, preferably, an aromatic organic, group of not more than 18 carbon atoms, a is zero, or, if R is an aromatic group, may alternatively be an integer of 1 to 3, and b is an integer of 1 to 6 such that (a+b) is at least 2.

Abstract: A method for the preparation of prepregs comprises(i) exposing to actinic radiation a layer of a liquid composition containing an epoxide resin, a photopolymerizable compound and a heat-activated curing agent for epoxide resins until the said composition solidifies to form an essentially solid continuous film due to photopolymerization of the said photopolymerizable compound while the epoxide resin remains substantially in the thermosettable state, and(ii) bringing together the film so formed and fibrous reinforcing material under conditions such that the said film flows about the fibers and the components of the said film and the fibers form a coherent structure.Preferably the liquid composition also contains a dual-functional substance which has in the same molecule both an epoxide group and a dissimilar group through which the substance can be photopolymerized.

Abstract: A layer of a liquid composition containing an epoxide resin as the sole photopolymerizable component, a heat-activated curing agent for epoxide resins, and preferably a photopolymerization catalyst, is exposed to actinic radiation until the layer solidifies to form an essentially solid, continuous film due to photopolymerization of the epoxide resin through epoxide groups, the resin remaining, however, still thermosettable by virtue of residual epoxide groups. The film so formed is contacted with fibrous reinforcing material and caused to flow about the fibers, suitably by applying heat and pressure, to form a prepreg. When desired, e.g., after the prepreg has been formed into some desired configuration or layers of prepreg have been stacked, the assembly may be cured by further heating.

Abstract: Polymerizable compositions comprise(a) a compound containing in the same molecule both at least one 1,2-epoxide group and at least two groups chosen from allyl, methallyl, and 1-propenyl groups, e.g., 2,2-bis(3-allyl-4-(glycidyloxy)phenyl)propane or bis(3-(1-propenyl)-4-(glycidyloxy)phenyl)methane, and(b) a compound containing at least two mercaptan groups per molecule, e.g., pentaerythritol tetrathioglycollate.The compositions are caused to polymerize by the action of irradiation or free-radical catalysts. They may, if desired, also contain a heat-curing crosslinking agent for epoxide resins; the epoxide-containing polymers so obtained can be subsequently crosslinked in situ. The compositions are useful in various two-stage operations, such as the production of multilayer printed circuits.

Abstract: A layer of a liquid composition containing an epoxide resin as the sole photopolymerizable component, a heat-activated curing agent for epoxide resins, and preferably a photopolymerization catalyst, is exposed to actinic radiation until the layer solidifies to form an essentially solid, continuous film due to photopolymerization of the epoxide resin through epoxide groups, the resin remaining, however, still thermosettable by virtue of residual epoxide groups. The film so formed is sandwiched between, and in contact with, surfaces to be bonded together, and the assembly is heated to cure the epoxide resin.

Abstract: The esters are soluble in an aqueous solution of a base before exposure to actinic radiation but, on exposure to actinic radiation, polymerize and become insoluble in such an aqueous solution. Development of photopolymerized images does not therefore require the use of toxic or flammable organic solvents. They contain free carboxyl groups and at least one unit of the formulae I-IV ##STR1## where R.sup.1 is a carbon atom chain containing specified groupings, such as one of formula --CH.dbd.CH--CO--CH.dbd.CH--, --CH.dbd.CHCO--, --COCH.dbd.CHC.sub.6 H.sub.4 CH.dbd.CHCO--, or ##STR2## and Y is oxygen or sulfur. They are obtained by the reaction of an at least dianhydride of a polycarboxylic acid with alcoholic hydroxyl groups of an alcohol containing at least one unit of formula I-IV.