36 results about "M-Cresol" patented technology

The invention discloses a preparation method of 6-nitro-m-cresol, and belongs to the technical field of organic synthesis.The method comprises the steps that raw materials are subjected to esterification, water washing, sulfonation, nitration, desulfonation and refining in sequence, and the 6-nitro-m-cresol is obtained. According to the method, it can be guaranteed that the intermediate product is the 6-nitro derivative, generation of isomer impurities such as 2-site and 4-site is greatly reduced from the source, the reaction path is clear, and atom economy is good. The method does not need to depend on complicated means such as time-consuming column chromatography or precise fractionation, the requirement for high purity can be met only through conventional extraction and crystallization operation, the technological process is simple, the method is very suitable for large-scale production, and the product purity (measured through HPLC (High Performance Liquid Chromatography)) can stably reach 98% or above.

The invention discloses application of m-cresol to prevention and treatment of pepper southern blight, and belongs to the field of plant disease prevention and treatment. According to the invention, it is found for the first time that m-cresol has an inhibition effect on sclerotium rolfsii, wherein EC50 of m-cresol is 0.1560 [mu] L / mL; the m-cresol with the concentration of 2 * EC50 can completely inhibit sclerotium germination, sclerotium generation and hypha growth of the sclerotium rolfsii. Furthermore, m-cresol can be used for preventing and treating pepper southern blight caused by sclerotium rolfsii, the morbidity and disease index of pepper southern blight can be effectively reduced by using a m-cresol solution with the concentration of 0.125% to perform root irrigation treatment on pepper planted in pathogenic bacteria soil, the relative prevention and treatment effect reaches 100%, and adverse reaction of pepper plants cannot be caused. The invention provides a new method for controlling the pepper southern blight by using a medicament, and the method has the advantages of high efficiency, low cost, low environmental harm and the like.

The invention discloses a production process method of an antioxidant BHT (butylated hydroxytoluene). The core of the method is to treat the recrystallization mother liquor: after the mother liquor is rectified to remove the solvent alcohol, the traditional high-temperature rectification is not adopted, and primary cooling crystallization, alkylation reaction and secondary cooling crystallization are sequentially carried out. Finally, the secondary mother liquor is produced as a liquid antioxidant LK51, and comprises 7-9% of 2-tert-butyl-p-cresol, about 35% of 4 (6)-tert-butyl-m-cresol, about 35% of 2, 6-di-tert-butyl-p-cresol, 4, 6-di-tert-butyl-m-cresol and other alkylphenols, and the total content of the alkylphenols is greater than 98%. The component is a mixture of various alkylphenols, has excellent oxidation resistance in lubricating oil, gasoline and other oil products, and can replace an antioxidant T501 and the like. According to the method disclosed by the invention, through process innovation and replacement of two-fraction alkylation of original rectification 2 by direct alkylation of the primary crystallization mother liquor, the yield of a BHT main product is increased, meanwhile, the high-added-value liquid antioxidant is co-produced, low-value heavy alkylphenol waste is eliminated, and dual improvement of energy conservation, consumption reduction and economic benefits is realized.

The invention discloses a positive photoresist composition suitable for an electroplating process as well as a preparation method and application of the positive photoresist composition, and belongs to the technical field of photoresist. The positive photoresist composition suitable for the electroplating process comprises the following components in parts by mass: 20-25 parts of high-molecular-weight high-sensitivity phenolic resin; 2 to 7 parts of plasticizing resin; 4-6 parts of a photosensitizer; 0.5-1 part of an additive; 61 to 73.5 parts of a solvent; wherein the molecular weight of the high-molecular-weight and high-sensitivity phenolic resin is 10000-20000, and the high-molecular-weight and high-sensitivity phenolic resin is low-ortho-position and high-branched phenolic resin in which the ratio of m-cresol to p-cresol is 8 / 2; the plasticizing resin is poly (p-hydroxystyrene) resin. The positive photoresist composition is suitable for an electroplating process, is used for solving the problem that a common photoresist is easy to break down in the electroplating process, and keeps good sensitivity characteristics at the same time.

The invention discloses a method for preparing m-cresol, p-cresol and m-cresol phenolic resin by using crude phenol refining residues. According to the method, an acidic silicon-aluminum oxide solid catalyst and a zirconium phosphate system are adopted, long alkyl groups such as ethyl groups on aromatic rings in a 3, 4-methyl ethyl phenol mixture are removed, methyl groups are reserved, phenol containing the long alkyl groups is converted into simple cresol, phenol and the like, and then vacuum distillation treatment is performed to obtain phenol, m-p-cresol and 2, 3, 5-tricresol; further reacting the mixed phenol obtained by rectification with aldehydes to obtain modified m-cresol-formaldehyde resin products such as p-cresol, 2, 3, 5-tricresol and the like; complex raw materials are converted into simple products with clear targets through the cracking reaction, sulfur and nitrogen impurities in most of the raw materials are removed by utilizing an acid environment in the cracking process, an additional refining step is omitted, and the grades of all subsequent products are improved. According to the method, the limitation of traditional rectification is broken through, the difficulty of physical separation is simplified through a chemical means, the phenol and the phenolic resin are co-produced, and the added value of the product is improved.

The invention belongs to the technical field of organic synthesis, and particularly discloses a thymol preparation method which comprises the following steps: filling a reaction tube of a fixed bed reactor with a catalyst, and heating m-cresol and isopropanol as raw materials in a fixed bed for gas-solid heterogeneous reaction to obtain thymol, the catalyst is an H-M1-ZSM-5 molecular sieve catalyst, the metal M1 is selected from Sn, Fe or Zn, and the ratio of n (Si) / n (Al + M1) of the molecular sieve is 25-30. According to the H-M1-ZSM-5 molecular sieve catalyst adopted by the invention, Sn, Fe or Zn is introduced into an existing H-type ZSM-5 molecular sieve, and the catalyst prepared by the invention has the advantages of long catalysis life, mild reaction, capability of being carried out under normal pressure, few byproducts, good selectivity, easiness in realization of reaction conditions and good industrial application prospect.

The application discloses a method and system for preparing thymol from m-p-isopropyl phenol / m-p-propyl phenol, wherein the m-p-isopropyl phenol / m-p-propyl phenol mixture is added into a reactor with a catalyst, and a reaction is carried out at a certain temperature; in the reaction, the m-p-isopropyl phenol and the like are subjected to a depropylation reaction to obtain a mixture of phenol and propylene; the reaction is completed under the control of a special online automatic analyzer; the mixture is cooled to a certain temperature; the propylene generated in the reaction is pressurized and stored in a spherical tank; an alkylation catalyst, a mixture of low-grade phenol and m-cresol are added into another reactor to carry out an alkylation reaction of phenol and propylene; and the reaction liquid is subjected to rectification to obtain high-purity phenol, high-purity m-cresol, o-isopropyl phenol, p-isopropyl phenol, 2-isopropyl-5-methyl phenol and 4-isopropyl phenol-3-methyl phenol; and the application can convert the mixed m-p-isopropyl phenol / m-p-propyl phenol with low value and small market demand into the marketable o-isopropyl phenol and p-isopropyl phenol and the like.

The invention provides a positive photosensitive resin composition, a resist film, a resist underlayer film, and a resist permanent film. The invention provides a positive photosensitive resin composition which is capable of obtaining a resist film with excellent developability, chemical resistance and heat resistance, and has good storage stability and thick film forming property. A positive photosensitive resin composition containing the following components (A) to (D): (A) a novolac phenolic resin having an acetal group-based protecting group, containing a phenol structural unit (a1) derived from m-cresol and / or o-cresol and an aldehyde structural unit (a2) derived from salicylaldehyde / (B) a polyhydroxystyrene having an acid-dissociable protecting group / (C) a photoacid generator / (D) a solvent.

The present invention is primarily directed to a polyamide powder composition useful for powder bed additive manufacturing, comprising: (a) 10% by weight to 90% by weight of a polyamide powder A having an intrinsic viscosity calculated according to equation (1) from the flow rate of a solution of the polymer and the solvent, measured in an Ubbelohde viscometer in accordance with ISO Standard 307:2019, apart from the use of m-cresol as the solvent and at a temperature of 20°C, of ​​0.8 to 2.8 with a span between 0.4 and 1.40; (b) 90% to 10% by weight of a polyamide powder B different from the polyamide powder A, having an intrinsic viscosity calculated as above of 0.8 to 2.8 with a span between 0.4 and 1.40; (c) 0 to 40 wt. % of additives selected from flow agents, stabilizers, optical brighteners, and energy absorbing additives and / or fillers; The present invention relates to a polyamide powder composition comprising: It is understood that polyamide powder B is derived from polyamide powder A, and the difference in intrinsic viscosity between powders A and B does not exceed 0.6 in absolute value.

The invention discloses a salt-tolerant strain for degrading m-cresol, the classification name of the salt-tolerant strain is Rhodococcus tectodiphilus, the strain number is GXGD-YZ-2510, and the preservation number is GDMCC No: 67304. The strain has the capability of stably growing and efficiently degrading the m-cresol in an environment with the salinity of 1-5 wt%, and the removal rate of the strain to the m-cresol is as high as 91.5% under the conditions that the salinity is 1 wt% and the initial m-cresol concentration is 100 mg / L. The method for treating the m-cresol-containing wastewater by using the strain has the characteristics of high efficiency, environmental protection and low cost, is suitable for treating the m-cresol-containing high-salt wastewater in the industries of petrifaction, chemical engineering, metallurgy and the like, has a wide application prospect, and provides novel microbial resources and technical support for biological treatment of refractory phenolic pollutants.

To provide a positive photosensitive resin composition giving a resist film excellent in developability and heat resistance and having good storage stability and thick film-forming property.SOLUTION: A positive photosensitive resin composition comprising the following components (A) to (C): (A) a molar ratio of a structural unit derived from m-cresol (a1), a structural unit derived from benzaldehyde (a2), a structural unit derived from salicylaldehyde (a3), and a structural unit derived from formaldehyde (a4) [(a1): (a2): (a3): (a4)] is 1.0:0.3 to 0.8:0.3 to 0.8:0.01 to 0.2, Novolac phenolic resin having acetal protective group / (B) photoacid generator / (C) solvent SELECTED DRAWING: None

The present application provides a kind of solid acid catalyst and the method for preparing 4,4'- butylidene bis (6-tert-butyl-m-cresol) antioxidant using the catalyst.The solid acid catalyst of the present application includes active component containing Lewis acid and catalyst carrier, the Lewis acid includes one or more of AlCl3, ZnCl2, SbCl3, the carrier includes pillared montmorillonite, the pillared montmorillonite is selected from one or more of titanium pillared montmorillonite, silicon pillared montmorillonite, aluminum pillared montmorillonite, zirconium pillared montmorillonite.The catalyst of the present application has high catalytic activity, good repeatability, simple separation and recovery process, high yield of antioxidant preparation method, green, economical and environmental preparation process.

Provided is an electrical connection member in which a sealing material is disposed between a terminal and a housing, and in which high sealing performance can be maintained even when the sealing material is in contact with lubricating oil. An electrical connection member (1) is provided with: a terminal (2); a housing (3) that holds the terminal (2); and a sealing material (4) disposed between the terminal (2) and the housing (3), the housing (3) containing a polyester-based resin and / or a polyamide-based resin, the sealing material (4) containing a thermoplastic polymer and being capable of dissolving or swelling with respect to both hexafluoroisopropanol and m-cresol. And the mass change rate is less than 20% when the product is immersed in lubricating oil at 100 DEG C for 8 hours.

The present invention provides an extruded composition comprising, by weight: a) 35 to 100%, in particular 35 to 96.9%, of at least one semi-crystalline aliphatic polyamide PA1, wherein the at least one semi-crystalline aliphatic polyamide PA1 comprises at least 30%, in particular at least 50%, of recycled semi-crystalline aliphatic polyamide PA2 recovered from pipes used or at the end of their life for the exploitation of offshore or onshore oil or gas deposits, in particular from offshore oil or gas deposits, and wherein the recycled semi-crystalline aliphatic polyamide PA2 has undergone a washing and / or compounding step after removal of the pipes and crushing to form granules, b) 0 to 65%, in particular 0 to 10%, of at least one reinforcing fiber; c) 0 to 40%, in particular 3 to 30%, of at least one impact modifier, d) 0 to 30%, in particular 0 to 15%, of fillers; e) 0 to 10%, in particular 0.1 to 5%, of at least one additive, Including, The sum of components a+b+c+d+e is 100% the intrinsic viscosity of the composition, measured in m-cresol at 20°C according to ISO307:2007, is 1.2 dL / g or more, particularly in the range of 1.2 dL / g to 1.7 dL / g; It relates to extruded compositions.

The application provides a molecular sieve for adsorptive separation of m-cresol and p-cresol and a preparation method and application thereof, wherein the molecular sieve is a ZSM-5 molecular sieve whose cation sites are jointly occupied by metal cations of group IA and rare earth metal cations, or a ZSM-5 molecular sieve whose cation sites are jointly occupied by metal cations of group IIA and rare earth metal cations. The pore size of the molecular sieve is regulated by complex modification of rare earth ions to realize selective adsorption of m-cresol and p-cresol, so that high-purity m-cresol and p-cresol can be obtained.

The present invention relates to a method for continuously preparing a polyamide prepolymer, the viscosity in solution of which is comprised between 0.25 dL / g and 0.70 dL / g, as measured according to ISO 307:2007 in m-cresol at 20° C.,the method being characterized in that it comprises a step of polycondensation on the basis of one or more polyamide precursor monomers, said polycondensation step being carried out in a extruder comprising at least two co-rotating conveying screws, the at least one monomer being previously added therein in solid or liquid form without being dissolved in a solvent or in water, and said polycondensation step being carried out without extracting the water formed during said polycondensation.

The present application belongs to the field of chemical technology, and particularly relates to a method and system for separating meta-cresol and para-cresol. The method comprises, in sequence, the steps of oxidation, neutralization, filtration, water vapor distillation and acidification. The neutralization comprises: passing in carbon dioxide until the pH of the system is 5.0-6.0. The present application selectively oxidizes para-cresol into para-hydroxybenzaldehyde, and separates the meta-cresol and para-hydroxybenzaldehyde by virtue of the difference in physical properties, thereby obtaining two products with high added value. By controlling the pH of the neutralization step to be within the range of 5.0-6.0, the yield can be improved.

The present disclosure provides, for example, a process for the production of a sodium salt of 2-(4-cyclopropyl-2-fluoroanilino)-3, 4-difluoro-5-[[3-fluoro-2-(methylsulfamoyl amino) pyridin-4-yl] methyl] benzamide (Compound 3), the process comprising the step of reacting 2-(4-cyclopropyl-2-fluoroanilino)-3, 4-difluoro-5-[[3-fluoro-2-(methylsulfamoyl amino) pyridin-4-yl] methyl] benzamide with a sodium salt of 2-(4-cyclopropyl-2-fluoroanilino)-3, 4-difluoro-5-[[3-fluoro-2-(methylsulfamoyl amino) pyridin-4-yl] methyl] benzamide (Compound 3). The method comprises the following steps of: mixing 2, 4-difluoro-5-[[3-fluoro-2-(methylsulfamoyl amino) pyridin-4-yl] methyl] benzamide, sodium tert-butoxide and m-cresol in a solvent to obtain a mixture containing the compound 3. The present disclosure provides a method for producing the compound 3, wherein a product having a higher content of the compound 3 can be obtained.

The utility model relates to the technical field of oxidation kettles, in particular to an oxidation kettle for preparing m-cresol with uniform mixing. According to the technical scheme, the device comprises an oxidation kettle body, a kettle cover and a stirring motor, the kettle cover is fixedly installed on the upper surface of the oxidation kettle body, a fixing frame is fixedly installed on the upper surface of the kettle cover, a reciprocating lead screw is rotationally connected to the top of the inner wall of the fixing frame, and a stirring shaft is fixedly connected to the tail end of the reciprocating lead screw; horizontal stirring blades are fixedly mounted on the outer surface of the stirring shaft, the outer surface of the reciprocating lead screw is movably sleeved with a sliding block, transverse plates are fixedly connected to the two sides of the outer surface of the sliding block, vertical rods are fixedly connected to the lower surfaces of the two transverse plates, and vertical stirring blades are fixedly mounted on the outer surfaces of the vertical rods. When m-cresol is prepared through oxidation of the oxidation kettle, raw materials in the oxidation kettle can be stirred in the horizontal and vertical directions, so that the mixing uniformity and efficiency of the raw materials are improved, and the preparation efficiency is improved.

The invention discloses a production process of 6-amino-m-cresol, which belongs to the technical field of fine chemical engineering, and comprises the following steps: putting 6-nitro-m-cresol into a reaction kettle, stirring, heating to reflux, adding a part of palladium carbon while stirring, slowly dripping hydrazine hydrate, controlling the temperature to reflux in the dripping process, keeping the temperature for reaction after the dripping is finished, and cooling to room temperature to obtain the 6-amino-m-cresol. Adding residual palladium-carbon for heat preservation reaction, thermally filtering reactants to recover palladium-carbon, and adding filtrate into the reaction kettle for cooling; carrying out suction filtration on the filtrate, then carrying out throwing filtration to obtain a filter cake, ethanol and residues, steaming the obtained residues with ethanol, adding the steamed residues into a reaction kettle, cooling to obtain a wet product 1, and washing the filter cake with water until the filter cake is white to obtain a wet product 2; and mixing and drying the wet product 1 and the wet product 2 to obtain the product. According to the production process of the 6-amino-m-cresol, the product delivery rate can be increased, the safety risk can be reduced, the purity can be ensured, the delivery time is shorter, the operation is simple, the yield can reach 78%, and the purity is 99.8%.

To provide a positive-type photosensitive resin composition capable of obtaining a resist film having a high i-line transmittance and excellent developability and heat resistance and having good storage stability.SOLUTION: There is provided a positive-type photosensitive resin composition comprising the following components (A) to (C): (A) a novolak-type phenolic resin containing a phenol structural unit (a1) derived from m-cresol and / or o-cresol and an aldehyde structural unit (a2) derived from salicylaldehyde and having an acetal-based protective group derived from a compound having two or more vinyl ether groups, (B) a photoacid generator and (C) a solvent.SELECTED DRAWING: None

The application discloses a preparation method of an m-p-cresol isomer separation and purification adsorbent, relates to an adsorption and desorption treatment process on a zeolite molecular sieve adsorbent, and belongs to the field of chemical separation applications. The LSX molecular sieve with the Si / Al atomic ratio in the range of 1.0-1.1 is fully stirred and mixed with a pillared bentonite and polyacrylamide, is formed into a ball, is exchanged with metal cations of group IA and group IIA, and is treated through drying, dehydration activation and the like to obtain a formed adsorbent. The formed adsorbent is loaded into a countercurrent simulated moving bed, continuous m-p-cresol material, a desorption agent and continuous extraction liquid, raffinate material are realized, and finally high-purity m-cresol and p-cresol products are obtained. The method is efficient, low in energy consumption, can obtain single cresol isomers, and has a good application prospect.

The utility model discloses a rectification device for separating m-cresol and p-cresol. The rectification device comprises a dealkylation reactor, a first flash tank, a second flash tank and a rectification tower, a feeding pipeline is mounted at a feeding hole of the dealkylation reactor, and a discharging pipeline is mounted at a discharging hole of the dealkylation reactor; a feed port of the first flash tank is connected with one end of the discharge pipeline, communicating pipelines are mounted at the bottoms of the first flash tank and the second flash tank, and compression recovery assemblies for compressing and recovering reaction products are mounted at the tops of the first flash tank and the second flash tank; an advanced dealkylation reaction process and a reflux process section design thereof are adopted, so that high-purity separation of m-cresol and p-cresol and efficient recovery of a byproduct isobutene can be realized, a very small amount of isobutene of p-cresol or m-cresol which is not separated can be circularly rectified, the waste of p-cresol or m-cresol and isobutene is reduced, and the production cost is reduced. The purity and the yield of the product are improved, the energy consumption and the production cost are reduced, and the method has a wide application prospect.

The invention provides a positive photosensitive resin composition, a photosensitive film, a resist film, a resist underlayer film, and a resist permanent film. The positive photosensitive resin composition contains the following components A to C. Component A: a novolac-type phenolic resin containing a phenolic structural unit a1 derived from m-cresol and / or o-cresol, an aldehyde structural unit a2 derived from acetaldehyde, and an aldehyde structural unit a3 derived from salicylaldehyde, and having an acetal group-based protecting group / Component B: a photoacid generator / Component C: a solvent.

The present application relates to chemical product separation equipment technical field, specifically disclose a kind of reaction crystallizer and crystallization method for m-p-cresol separation and purification, comprising: rotating rod;Sealing box;Filter screen;Conical tube;Discharge pipe.By making mother liquor drive p-cresol crystal from spray tube, and the p-cresol crystal that sprays hits filter screen, makes p-cresol crystal scatter broken, and m-cresol solution wrapped in crystal will splash out and separate from crystal at this time, and m-cresol solution that splashes out is discharged through filter screen, so it can effectively avoid p-cresol crystal to have m-cresol solution, to effectively avoid the purity of m, p-cresol after separation reduces.

The utility model relates to the technical field of purification devices, and discloses a purification device convenient to clean for preparing m-cresol, which comprises a box body, a sieve plate is placed on one side of the box body, a bracket is fixedly mounted on one side of the sieve plate, and a forward and reverse motor is fixedly mounted on the outer wall of the box body close to the inner side of the bracket; supporting rods are fixedly installed at the four corners of the bottom of the box body. By arranging the sieve plate, the two groups of filter screens and the screw rod, when a single group of filter screens is blocked, the screw rod can be driven by the transmission shaft of the positive and negative motor to rotate clockwise, and the threaded barrel and the bracket can be driven to move towards the box body until the other group of filter screens are aligned with the box body, and materials are added for filtering; the external filter screen has the effect of being convenient to clean compared with cleaning in the box or cleaning in a dismounting manner, and the problem that the filtering and storing efficiency is affected due to shutdown blockage cleaning can be avoided by circularly and alternately using the two filter screens in this way.

This invention discloses a method and apparatus for the continuous production of m-cresol by coupling a dehydrogenation reaction with distillation separation, relating to the field of m-cresol preparation technology. Addressing the drawbacks of traditional two-step processes—namely, their lengthy flow, high equipment investment, numerous side reactions, and the shortcomings of existing reactive distillations—such as the tendency for solid catalysts to accumulate carbon and become deactivated, the lack of a heavy component removal section, and the inability to operate continuously for extended periods—this invention employs a three-stage reactive distillation column architecture with a homogeneous acid catalytic system. 4,6-Di-tert-butyl-m-cresol enters the reaction section for catalytic dehydrogenation, producing m-cresol and isobutylene. The light m-cresol and isobutylene are drawn off from the top of the column, while the heavy component impurities descend into the stripping section. After separation, unreacted feedstock is refluxed back to the reaction section for recycling, while the heavy component impurities are discharged from the bottom of the vessel. This invention overcomes the limitations of traditional step-by-step processes, eliminates the need for external separation equipment, effectively suppresses reverse and side reactions, achieves high feedstock utilization and excellent product purity, simplifies the process flow, and enables long-term steady-state continuous production, showing broad prospects for industrial application.

The application provides a catalyst for continuous methylation of m-cresol, a preparation method and application thereof. The catalyst comprises a carrier and an active substance loaded on the carrier; wherein the carrier is calcined pseudo-boehmite, and the active substance comprises a platinum compound and a heteropoly acid; the platinum compound accounts for 0.05-5% of the mass of the carrier; and the heteropoly acid accounts for 0.5-10% of the mass of the carrier. The platinum compound in the catalyst has a function of inhibiting coking, and loading the platinum compound on the carrier can inhibit the speed of olefin polymerization and coking on the catalyst, so that the stability of the catalyst is improved, the service life of the catalyst is prolonged, and the catalyst can be reactivated after the activity of the catalyst is reduced. Meanwhile, the catalyst loaded with the heteropoly acid can appropriately increase the acidity of the catalyst, so that the catalytic activity of the catalyst is improved; and the multi-atom in the heteropoly acid can also adjust the reaction site of the catalyst, so that the selectivity of m-cresol and olefin reaction is improved.

The present invention relates to a method for preparing cresol, the method comprising a step of reacting halotoluene with potassium t-butoxide (K(O-C(CH3)3)). The present invention can lower the reaction temperature and increase the selectivity and yield of m-cresol, compared to when NaOH is used.

To provide a positive photosensitive resin composition giving a resist film excellent in developability, chemical resistance and heat resistance and having good storage stability and thick film forming property.SOLUTION: A positive photosensitive resin composition comprising the following components (A) to (D): (A) a novolak phenolic resin containing a phenol structural unit (a1) derived from m-cresol and / or o-cresol and an aldehyde structural unit (a2) derived from salicylaldehyde and having an acetal protective group, (B) a polyhydroxystyrene having an acid-dissociable protective group, (C) a photoacid generator, and (D) a solvent SELECTED DRAWING: None