Resin composition and preparation method thereof, prepreg, laminated board and printed circuit board

Abstract

The invention relates to a resin composition and a preparation method thereof, a prepreg, a laminated board and a printed circuit board. The resin composition is prepared from the following components in parts by mass: 30 to 80 parts of modified bismaleimide prepolymer and 20 to 60 parts of cyanate ester resin, the modified bismaleimide prepolymer is prepared from the following raw materials: bismaleimide resin and a diamine compound, wherein the diamine compound contains a benzocyclobutene structure. In the resin composition, the modified bismaleimide prepolymer prepared from specific preparation raw materials and the cyanate ester resin are matched according to a specific proportion, so that the resin composition has a relatively low thermal expansion coefficient; meanwhile, the glass transition temperature and the thermal decomposition temperature are higher, the peel strength and the elastic modulus are higher, and the dielectric constant and the dielectric loss are lower, so that the high thermal stability, the size stability, the mechanical property and the dielectric property are better.

Description

Technical Field

[0001] The present application relates to the technical field of communication materials, and in particular to a resin composition and a preparation method thereof, a prepreg, a laminate and a printed circuit board. Background Art

[0002] With the rapid development of electronic information technology, more and more electronic products are moving towards high frequency, high integration and small size, and the demand for high-performance electronic devices is growing.

[0003] Bismaleimide resin is a maleimide-terminated bifunctional polymer that can form a cross-linked structure through addition polymerization. As a typical high-performance polymer, bismaleimide resin has excellent thermal stability, excellent mechanical strength and good dielectric properties, and is widely used in the field of electronic packaging. However, as one of the most important thermosetting materials, compared with most metals such as copper with a thermal expansion coefficient of 16 ppm / ℃, bismaleimide resin has a higher thermal expansion coefficient of 40 ppm / ℃~120 ppm / ℃. The high expansion coefficient of bismaleimide resin hinders its application in certain fields that require dimensional stability.

[0004] Therefore, it is necessary to improve the traditional technology. Summary of the invention

[0005] Based on this, the present application provides a resin composition with a low thermal expansion coefficient and a preparation method thereof, a prepreg, a laminate and a printed circuit board.

[0006] The technical solution of this application to solve the above technical problems is as follows.

[0007] On the one hand, the present application provides a resin composition, which comprises the following components by weight:

[0008] 30-80 parts of modified bismaleimide prepolymer; and

[0009] 20-60 parts of cyanate resin;

[0010] The raw materials for preparing the modified bismaleimide prepolymer include bismaleimide resin and a diamine compound, and the diamine compound contains a benzocyclobutene structure.

[0011] In some embodiments, the resin composition includes the following components in parts by mass:

[0012] 40-80 parts of modified bismaleimide prepolymer; and

[0013] 30~50 parts of cyanate resin.

[0014] In some embodiments, the resin composition includes the following components in parts by mass:

[0015] 60-80 parts of modified bismaleimide prepolymer; and

[0016] 35-45 parts of cyanate resin.

[0017] In some of the embodiments, in the resin composition, the mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin is 1:0.5~1; optionally, the mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin is 1:0.5~0.75.

[0018] In some of the embodiments, in the resin composition, in the raw material for preparing the modified bismaleimide prepolymer, the mass ratio of the bismaleimide resin to the diamine compound is 1:1~3; optionally, the mass ratio of the bismaleimide resin to the diamine compound is 1:1.4~2.

[0019] In some embodiments, in the resin composition, the structure of the diamine compound is as shown in formula (I):

[0020] .

[0021] In some of the embodiments, in the resin composition, the monomer of the bismaleimide resin includes at least one of N-phenylmaleimide, N-(2-methylphenyl)maleimide, N-(4-methylphenyl)maleimide, N-(2,6-dimethylphenyl)maleimide, bis(4-maleimidophenyl)methane, 2,2-bis(4-(4-maleimidophenoxy)-phenyl)propane, bis(3,5-dimethyl-4-maleimidophenyl)methane, bis(3-ethyl-5-methyl-4-maleimidophenyl)methane, bis(3,5-diethyl-4-maleimidophenyl)methane, polyphenylmethane bismaleimide, bismaleimide containing biphenyl structure and polymaleimide.

[0022] In some of the embodiments, in the resin composition, the cyanate ester resin includes at least one of bisphenol A type cyanate ester resin, phenolic cyanate ester resin, bisphenol F type cyanate ester resin, multifunctional cyanate ester resin, bisphenol M type cyanate ester resin, bisphenol E type cyanate ester resin and dicyclopentadiene bisphenol type cyanate ester resin.

[0023] In some of the embodiments, the resin composition further comprises 5 to 20 parts by mass of a flame retardant; optionally, the flame retardant comprises at least one of decabromodiphenylethane, tetrabromobisphenol A, brominated epoxy resin, phosphorus-containing epoxy resin, phosphorus-containing phenolic resin, phosphazene compound, phosphate ester compound and phosphorus-containing cyanate ester.

[0024] In some embodiments, the resin composition further comprises 10 to 40 parts by mass of an inorganic filler; optionally, the inorganic filler comprises at least one of zirconium vanadate, zirconium tungstate, hafnium tungstate, glass-ceramics, eucryptite, silicon dioxide, quartz, mica powder, titanium dioxide, magnesium oxide, magnesium hydroxide, talc, aluminum oxide, silicon carbide, boron nitride, aluminum nitride, molybdenum oxide, barium sulfate, zinc molybdate, zinc borate, zinc stannate, zinc oxide, strontium titanate, barium titanate, calcium titanate, clay and kaolin.

[0025] On the one hand, the present application provides a method for preparing a resin composition, comprising the following steps:

[0026] 30-80 parts of modified bismaleimide prepolymer and 20-60 parts of cyanate resin are mixed by weight; the raw materials for preparing the modified bismaleimide prepolymer include bismaleimide resin and diamine compound, and the diamine compound contains benzocyclobutene structure.

[0027] In some embodiments, in the method for preparing the resin composition, the preparation of the modified bismaleimide prepolymer comprises the following steps:

[0028] The bismaleimide resin and the diamine compound are mixed to perform a prepolymerization reaction; optionally, the temperature of the prepolymerization reaction is 150° C. to 250° C.

[0029] In one aspect, the present application provides a resin film, which includes the above-mentioned resin composition or the resin composition prepared by the above-mentioned preparation method.

[0030] On one hand, the present application provides a prepreg, comprising a reinforcing material and the above-mentioned resin composition attached to the reinforcing material or the resin composition prepared by the above-mentioned preparation method.

[0031] In one aspect, the present application provides a laminate comprising at least one of the above-mentioned resin film and the above-mentioned prepreg.

[0032] On the one hand, the present application provides a method for preparing a laminate, comprising the following steps:

[0033] At least one of the resin film and the prepreg is thermocompression molded.

[0034] In some of the embodiments, in the method for preparing the laminate, the hot pressing molding includes a first hot pressing molding and a second hot pressing molding performed sequentially, the temperature of the first hot pressing molding is 150℃~250℃, and the temperature of the second hot pressing molding is 250℃~400℃.

[0035] On one hand, the present application provides a printed circuit board, comprising at least one of the above-mentioned resin film, the above-mentioned prepreg, the above-mentioned laminate, and the laminate prepared by the above-mentioned method for preparing the laminate.

[0036] Compared with the prior art, the resin composition of the present application has the following beneficial effects:

[0037] The resin composition of the present application comprises a modified bismaleimide prepolymer and a cyanate resin in a specific ratio. The raw materials for preparing the modified bismaleimide prepolymer comprise a bismaleimide resin and a diamine compound containing a benzocyclobutene structure. The diamine compound can effectively increase the chain rigidity of the bismaleimide resin and effectively reduce the crosslinking density of the bismaleimide resin. At the same time, the benzocyclobutene structures in the modified bismaleimide prepolymer can undergo cycloaddition to generate a foldable eight-membered ring. The boat-shaped configuration under natural conditions is transformed into a reclining chair configuration after heating. The configuration change forms a volume shrinkage phenomenon. When combined with the cyanate resin in a specific ratio, the thermal expansion coefficient of the resin composition can be reduced as a whole.

[0038] The resin composition of the present application is prepared by mixing a modified bismaleimide prepolymer prepared from specific raw materials and a cyanate ester resin in a specific ratio, and not only has a low thermal expansion coefficient, but also has a high glass transition temperature and thermal decomposition temperature, high peel strength and elastic modulus, and low dielectric constant and dielectric loss, thereby having good high thermal stability, dimensional stability, mechanical properties and dielectric properties. DETAILED DESCRIPTION

[0039] The present application will be further described in detail below in conjunction with the embodiments and examples. It should be understood that these embodiments and examples are only used to illustrate the present application and are not used to limit the scope of the present application. The purpose of providing these embodiments and examples is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0040] It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various changes or modifications without violating the connotation of the present application, and the equivalent forms obtained also fall within the scope of protection of the present application. For example, the features illustrated or described as part of one embodiment can be combined in another embodiment in a suitable manner to produce a new embodiment. In addition, in the description below, a large number of specific details are given in order to provide a more comprehensive understanding of the present application. It should be understood that the present application can be implemented without one or more of these details.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing implementation modes and embodiments and are not intended to limit this application.

[0042] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0043] In the present application, "plurality", "multiple", "multiple times", etc., unless otherwise specified, refer to a quantity greater than 2 or equal to 2. For example, "one or more" means one or greater than or equal to two.

[0044] As used herein, "combination thereof", "any combination thereof", "any combination thereof" etc. include all suitable combinations of any two or more of the listed items.

[0045] Herein, the “suitable” mentioned in “suitable combination”, “suitable method”, “any suitable method”, etc., shall be based on the ability to implement the technical solution of this application, solve the technical problems of this application, and achieve the expected technical effects of this application.

[0046] Herein, "preferred", "better", "more preferred", and "suitable" are only used to describe implementation methods or examples with better effects, and it should be understood that they do not constitute a limitation on the scope of protection of this application. If multiple "preferred" items appear in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "preferred" item is independent.

[0047] In the present application, "further", "further", "particularly" and the like are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of the present application.

[0048] In this application, "optionally", "optional", and "optional" mean optional or dispensable, that is, any one of the two parallel schemes of "yes" or "no". If multiple "options" appear in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "optional" is independent.

[0049] In the present application, the terms "first", "second", "third", "fourth", etc. in "the first aspect", "the second aspect", "the third aspect", "the fourth aspect", etc. are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first", "second", "third", "fourth", etc. only serve the purpose of non-exhaustive enumeration and description, and it should be understood that they do not constitute a closed limitation on quantity.

[0050] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0051] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values ​​in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum value and the maximum value) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to the integers in the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical range disclosed herein should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows broadly including numerical interval types such as percentage intervals, ratio intervals, and ratio intervals.

[0052] The temperature parameters in this application, unless otherwise specified, are allowed to be either constant temperature treatment or to vary within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within the range of ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are allowed.

[0053] In this application, the term "room temperature" or "normal temperature" generally refers to 4°C to 35°C, for example, 20°C ± 5°C. In some embodiments of this application, "room temperature" or "normal temperature" refers to 10°C to 30°C. In some embodiments of this application, "room temperature" or "normal temperature" refers to 20°C to 30°C.

[0054] In this application, when referring to the unit of a data range, if there is a unit only after the right endpoint, it means that the units of the left and right endpoints are the same. For example, 3~5 h means that the units of the left endpoint "3" and the right endpoint "5" are both h (hours).

[0055] All documents mentioned in this application are cited as references in this application, just as each document is cited as reference separately. Unless they conflict with the invention purpose and / or technical solution of this application, the cited documents involved in this application are cited with all contents and all purposes. When the cited documents are involved in this application, the definitions of relevant technical features, terms, nouns, phrases, etc. in the cited documents are also cited. When the cited documents are involved in this application, the examples and preferred methods of the cited relevant technical features can also be incorporated into this application as references, but are limited to the implementation of this application. It should be understood that when the cited content conflicts with the description in this application, the present application shall prevail or be modified adaptively according to the description of this application.

[0056] The mass or weight of the relevant components mentioned in the specification of the embodiments of the present application may not only refer to the specific content of each component, but also indicate the proportional relationship of the mass or weight between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the specification of the embodiments of the present application, it is within the scope disclosed in the specification of the embodiments of the present application. Specifically, the mass or weight described in the specification of the embodiments of the present application may be units known in the chemical industry such as μg, mg, g, and kg.

[0057] An embodiment of the present application provides a resin composition, which comprises the following components in parts by mass:

[0058] 30-80 parts of modified bismaleimide prepolymer; and

[0059] 20-60 parts of cyanate resin;

[0060] The raw materials for preparing the modified bismaleimide prepolymer include bismaleimide resin and a diamine compound, and the diamine compound contains a benzocyclobutene structure.

[0061] The resin composition provided by the present application comprises a modified bismaleimide prepolymer and a cyanate resin in a specific ratio. The raw materials for preparing the modified bismaleimide prepolymer comprise a bismaleimide resin and a diamine compound containing a benzocyclobutene structure. The diamine compound can effectively increase the chain stiffness of the bismaleimide resin and effectively reduce the crosslinking density of the bismaleimide resin. At the same time, the benzocyclobutene structures in the modified bismaleimide prepolymer can undergo cycloaddition to generate a foldable eight-membered ring. The boat-shaped configuration under natural conditions is transformed into a reclining chair configuration after heating. The configuration change forms a volume shrinkage phenomenon. When combined with the cyanate resin in a specific ratio, the thermal expansion coefficient of the resin composition can be reduced as a whole.

[0062] By mixing the modified bismaleimide prepolymer prepared from specific raw materials and the cyanate resin in a specific ratio, the product not only has a lower thermal expansion coefficient, but also has a higher glass transition temperature and thermal decomposition temperature, higher peel strength and elastic modulus, and lower dielectric constant and dielectric loss, thereby having better high thermal stability, dimensional stability, mechanical properties and dielectric properties; it can be applied to the fields of integrated circuit packaging and microelectronic devices.

[0063] It can be understood that in the resin composition, the mass fraction of the modified bismaleimide prepolymer includes, but is not limited to, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, 40 parts, 41 parts, 42 parts, 43 parts, 44 parts, 45 parts, 46 parts, 47 parts, 48 ​​parts, 49 parts, 50 parts, 51 parts, 52 parts, 53 parts, 54 parts, 55 parts, 56 parts, 57 parts, 58 parts, 59 parts, 60 parts, 61 parts, 62 parts, 63 parts, 64 parts, 65 parts, 66 parts, 67 parts, 68 parts, 69 parts, 70 parts, 71 parts, 72 parts, 73 parts, 74 parts, 75 parts, 76 parts , 77 parts, 78 parts, 79 parts, 80 parts; the mass parts of cyanate ester resin include but are not limited to 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, 40 parts, 41 parts, 42 parts, 43 parts, 44 parts, 45 parts, 46 parts, 47 parts, 48 ​​parts, 49 parts, 50 parts, 51 parts, 52 parts, 53 parts, 54 parts, 55 parts, 56 parts, 57 parts, 58 parts, 59 parts, 60 parts; in some examples, it can be within the range composed of any two of these point values ​​as end values, the same below.

[0064] In some of the examples, the resin composition includes the following components by weight:

[0065] 40-80 parts of modified bismaleimide prepolymer; and

[0066] 30~50 parts of cyanate resin.

[0067] In some of the examples, the resin composition includes the following components by weight:

[0068] 60-80 parts of modified bismaleimide prepolymer; and

[0069] 35-45 parts of cyanate resin.

[0070] In some of the examples, in the resin composition, the mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin is 1:0.5~1.

[0071] It can be understood that the mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin includes but is not limited to 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, and 1:1.

[0072] Optionally, the mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin is 1:0.5-0.75.

[0073] In some of the examples, in the resin composition, in the raw material for preparing the modified bismaleimide prepolymer, the mass ratio of the bismaleimide resin to the diamine compound is 1:1~3.

[0074] It will be appreciated that the mass ratio of the bismaleimide resin to the diamine compound includes but is not limited to 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:2.1, 1:2.2, 1:2.3, 1:2.4, 1:2.5, 1:2.6, 1:2.7, 1:2.8, 1:2.9, 1:3.

[0075] Optionally, the mass ratio of the bismaleimide resin to the diamine compound is 1:1.4-2.

[0076] In some of the examples, in the resin composition, the structure of the diamine compound is as shown in formula (I):

[0077] .

[0078] In some of the examples, in the resin composition, the monomer of the bismaleimide resin includes at least one of N-phenylmaleimide, N-(2-methylphenyl)maleimide, N-(4-methylphenyl)maleimide, N-(2,6-dimethylphenyl)maleimide, bis(4-maleimidophenyl)methane, 2,2-bis(4-(4-maleimidophenoxy)-phenyl)propane, bis(3,5-dimethyl-4-maleimidophenyl)methane, bis(3-ethyl-5-methyl-4-maleimidophenyl)methane, bis(3,5-diethyl-4-maleimidophenyl)methane, polyphenylmethane bismaleimide, bismaleimide containing a biphenyl structure, and polymaleimide.

[0079] In some of the examples, in the resin composition, the cyanate ester resin includes at least one of bisphenol A type cyanate ester resin, novolac type cyanate ester resin, bisphenol F type cyanate ester resin, multifunctional type cyanate ester resin, bisphenol M type cyanate ester resin, bisphenol E type cyanate ester resin and dicyclopentadiene bisphenol type cyanate ester resin.

[0080] In some of the examples, the resin composition further comprises 10 to 40 parts by mass of an inorganic filler.

[0081] It can be understood that in the resin composition, the mass fraction of inorganic filler includes but is not limited to 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, and 40 parts by mass.

[0082] In some of the examples, in the resin composition, the inorganic filler includes at least one of zirconium vanadate, zirconium tungstate, hafnium tungstate, microcrystalline glass, eucryptite, silica (spherical, composite or fused), quartz, mica powder, titanium dioxide, magnesium oxide, magnesium hydroxide, talc, aluminum oxide, silicon carbide, boron nitride, aluminum nitride, molybdenum oxide, barium sulfate, zinc molybdate, zinc borate, zinc stannate, zinc oxide, strontium titanate, barium titanate, calcium titanate, clay and kaolin.

[0083] In some of the examples, the resin composition further comprises 5 to 20 parts by mass of a flame retardant.

[0084] It can be understood that in the resin composition, the mass fraction of the flame retardant includes but is not limited to 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, and 20 parts by mass.

[0085] In some of the examples, in the resin composition, the flame retardant includes at least one of decabromodiphenylethane, tetrabromobisphenol A, brominated epoxy resin, phosphorus-containing epoxy resin, phosphorus-containing phenolic resin, phosphazene compound, phosphate ester compound and phosphorus-containing cyanate ester.

[0086] In some of the examples, the resin composition further includes 60 to 160 parts by mass of the first solvent.

[0087] It can be understood that in the resin composition, the mass fraction of the first solvent includes but is not limited to 60 parts, 70 parts, 80 parts, 90 parts, 100 parts, 110 parts, 120 parts, 130 parts, 140 parts, 150 parts, and 160 parts.

[0088] Optionally, the first solvent includes at least one of butanone and propylene glycol methyl ether. Further, the first solvent includes butanone and propylene glycol methyl ether. Further, the mass ratio of butanone to propylene glycol methyl ether is 0.5 to 2:1. Optionally, the mass ratio of butanone to propylene glycol methyl ether is 1:1.

[0089] It is understood that the resin composition provided in the present application may further include additives commonly used in the art, including but not limited to at least one of a curing accelerator, a coupling agent, and a toughening agent, etc. Further, the curing accelerator includes 2-methylimidazole.

[0090] An embodiment of the present application provides a method for preparing a resin composition, comprising the following steps:

[0091] 30-80 parts of modified bismaleimide prepolymer and 20-60 parts of cyanate resin are mixed by weight; the raw materials for preparing the modified bismaleimide prepolymer include bismaleimide resin and diamine compound, and the diamine compound contains benzocyclobutene structure.

[0092] It can be understood that the preparation method of the resin composition can produce the above-mentioned resin composition, the above-mentioned resin composition can be produced by the preparation method of the resin composition, and the characteristics between the above-mentioned resin composition and the preparation method of the resin composition can be mutually applicable.

[0093] The resin composition prepared by the preparation method not only has a low thermal expansion coefficient, but also has a high glass transition temperature and thermal decomposition temperature, a high peel strength and elastic modulus, and a low dielectric constant and dielectric loss, thereby having good high thermal stability, dimensional stability, mechanical properties and dielectric properties.

[0094] In some of the examples, in the method for preparing the resin composition, the preparation of the modified bismaleimide prepolymer comprises the following steps:

[0095] The bismaleimide resin and the diamine compound are mixed to perform a prepolymerization reaction.

[0096] In some of the examples, in the step of preparing the modified bismaleimide prepolymer, the prepolymerization reaction temperature is 150° C. to 250° C.

[0097] It is understood that the temperature of the prepolymerization reaction includes but is not limited to 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, and 250°C.

[0098] In some examples, the step of mixing the bismaleimide resin and the diamine compound further includes the step of adding a second solvent. Further, the second solvent includes cyclohexanone.

[0099] In some of these examples, the preparation of the diamine compound includes the following steps:

[0100] The 2,5-dicarboxylic acid benzocyclobutene, benzyltriethylammonium chloride and thionyl chloride are mixed to carry out an acyl chlorination reaction to prepare an acyl chloride compound;

[0101] The acyl chloride compound, 4,4'-diaminodiphenylmethane and the fourth solvent are mixed to carry out an amidation reaction to prepare a diamine compound.

[0102] The reaction route is as follows:

[0103]

[0104] In some of these examples, in the step of preparing the diamine compound, the acyl chlorination reaction is carried out at reflux temperature.

[0105] In some of the examples, in the step of preparing the diamine compound, the fourth solvent includes dichloromethane.

[0106] In some of the examples, in the step of preparing the diamine compound, the amidation reaction is carried out under the action of a catalyst; further, the catalyst includes triethylamine.

[0107] In some of these examples, in the step of preparing the diamine compound, the amidation reaction is carried out at room temperature.

[0108] One embodiment of the present application provides a resin film, which includes the above-mentioned resin composition or the resin composition prepared by the above-mentioned preparation method.

[0109] The resin film of the present application includes the above resin composition or the resin composition prepared by the above preparation method, and thus has at least the same advantages as the above resin composition or the resin composition prepared by the above preparation method.

[0110] An embodiment of the present application provides a method for preparing a resin film, comprising the following steps:

[0111] The resin composition or the resin composition obtained by the preparation method is coated on a release material and then dried and / or semi-cured to obtain the release material.

[0112] One embodiment of the present application provides a prepreg, comprising a reinforcing material and the above-mentioned resin composition attached to the reinforcing material or the resin composition prepared by the above-mentioned preparation method.

[0113] The prepreg of the present application includes the above resin composition or the resin composition prepared by the above preparation method, and thus has at least the same advantages as the above resin composition or the resin composition prepared by the above preparation method.

[0114] In some of the examples, in the prepreg, the reinforcing material includes but is not limited to at least one of an inorganic fiber material and an organic fiber material.

[0115] Furthermore, the inorganic fiber material includes but is not limited to at least one of glass fiber (including different types such as E, NE, D, S, T, etc.), carbon fiber, silicon carbide fiber, and asbestos fiber.

[0116] Furthermore, the organic fiber material includes but is not limited to at least one of nylon, ultra-high molecular weight polyethylene fiber, aramid fiber, polyimide fiber, polyester fiber and cotton fiber.

[0117] In some of these examples, the resin composition accounts for 40% to 60% by weight of the prepreg.

[0118] It can be understood that the mass proportion of the resin composition in the prepreg includes but is not limited to 40%, 50%, and 60%.

[0119] An embodiment of the present application provides a method for preparing a prepreg, comprising the following steps:

[0120] The reinforcing material is impregnated into the resin composition or the resin composition obtained by the preparation method, and the prepreg is obtained by semi-curing treatment.

[0121] It can be understood that the above resin composition or the resin composition obtained by the above preparation method covers the surface of the reinforcing material.

[0122] In some of the examples, in the method for preparing the prepreg, the semi-curing treatment is performed at a temperature of 150°C to 250°C and for a time of 2 min to 10 min.

[0123] It will be understood that the semi-curing temperature includes but is not limited to 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, and 250°C; and the time includes but is not limited to 2 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, and 10 min.

[0124] One embodiment of the present application provides a laminate, comprising at least one of the above-mentioned resin film and the above-mentioned prepreg.

[0125] The laminate of the present application includes at least one of the above-mentioned resin film and the above-mentioned prepreg, and thus has at least the same advantages as the above-mentioned resin film or the above-mentioned prepreg.

[0126] It can be understood that the laminate includes one or two of the above-mentioned resin film and the above-mentioned prepreg. Furthermore, the resin film and the prepreg can be one or more respectively.

[0127] In some of the examples, in the laminate, a metal foil is provided on one side or both sides of the laminate. Further, the metal foil includes a metal copper foil. It can be understood that the laminate is a copper clad laminate at this time. Accordingly, an embodiment of the present application provides a copper clad laminate, comprising at least one of the above-mentioned resin film and the above-mentioned prepreg, and a metal copper foil provided on at least one side of the resin film or the prepreg. Further, the thickness of the metal foil is 3 μm~70 μm.

[0128] An embodiment of the present application provides a method for preparing a laminate, comprising the following steps:

[0129] At least one of the resin film and the prepreg is thermocompression molded.

[0130] In some of the examples, in the method for preparing the laminate, the hot pressing molding includes a first hot pressing molding and a second hot pressing molding performed sequentially, the temperature of the first hot pressing molding is 150°C to 250°C, and the temperature of the second hot pressing molding is 250°C to 400°C.

[0131] It can be understood that the temperature of the first hot pressing molding includes but is not limited to 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 230℃, 240℃, and 250℃; the temperature of the second hot pressing molding includes but is not limited to 250℃, 260℃, 270℃, 280℃, 290℃, 300℃, 310℃, 320℃, 330℃, 340℃, 350℃, 360℃, 370℃, 380℃, 390℃, and 400℃.

[0132] It can be understood that during the first hot pressing process at 150°C to 250°C, the secondary amine and the unreacted primary amine react with the bismaleimide, and the maleimide group also undergoes homopolymerization, including the following reactions:

[0133]

[0134]

[0135]

[0136] During the second hot pressing process at 250℃~400℃, a cycloaddition reaction occurs:

[0137]

[0138] Furthermore, the cycloaddition reaction generates a foldable eight-membered ring, and the boat-shaped configuration under natural conditions changes to a lounge chair configuration after heating:

[0139]

[0140] In some of the examples, in the method for preparing the laminate, the time of the first hot pressing molding is 100 min to 300 min.

[0141] It can be understood that the time for the first hot pressing molding includes but is not limited to 100min, 110min, 120min, 130min, 140min, 150min, 160min, 170min, 180min, 190min, 200min, 210min, 220min, 230min, 240min, 250min, 260min, 270min, 280min, 290min, and 300min.

[0142] In some of the examples, in the method for preparing the laminate, the time of the second hot pressing molding is 30 min to 200 min.

[0143] It will be appreciated that the time for the second hot pressing molding includes but is not limited to 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min, 120 min, 130 min, 140 min, 150 min, 160 min, 170 min, 180 min, 190 min, and 200 min.

[0144] In some of the examples, in the method for preparing the laminate, the pressure of the first hot press molding and the second hot press molding are independently 10 kgf / cm 2 ~30 kgf / cm 2 .

[0145] It is understood that the pressures of the first hot pressing molding and the second hot pressing molding are independently including but not limited to 10 kgf / cm 2 , 12 kgf / cm 2 、15 kgf / cm 2 、18 kgf / cm 2 , 20 kgf / cm 2 , 22 kgf / cm 2 , 25 kgf / cm 2 、28 kgf / cm 2 、30 kgf / cm 2

[0146] In some of the examples, in the method for preparing the laminate, the vacuum degrees of the first hot pressing molding and the second hot pressing molding are both less than 2 kPa.

[0147] It can be understood that in the method for preparing the laminate, the resin film and the prepreg can be independently a plurality of each other, and a plurality of each refers to at least one; further, a plurality of each can be stacked.

[0148] In some of the examples, the method for preparing the laminate further includes, before the thermoforming step, a step of providing a metal foil on at least one side of at least one of the resin film and the prepreg.

[0149] It can be understood that the metal foil is arranged on the resin film and the prepreg is on the outside; that is, the metal foil is arranged on one side or both sides of the laminated board finally obtained by lamination.

[0150] One embodiment of the present application provides a printed circuit board, comprising at least one of the above-mentioned resin film, the above-mentioned prepreg, the above-mentioned laminate, and the laminate obtained by the above-mentioned method for preparing the laminate.

[0151] The printed circuit board of the present application includes at least one of the above-mentioned resin film, the above-mentioned prepreg, the above-mentioned laminate, and the laminate produced by the preparation method of the above-mentioned laminate, and thus has at least the same advantages as the above-mentioned resin film, the above-mentioned prepreg, the above-mentioned laminate, and the laminate produced by the preparation method of the above-mentioned laminate.

[0152] An embodiment of the present application provides a communication device, including the above-mentioned printed circuit board.

[0153] It is understood that the communication device includes but is not limited to at least one of a smart phone, a tablet computer, a smart watch, etc.

[0154] In the field of consumer electronics, electronic products cannot do without copper clad laminates: from smartphones, tablets to smart watches, the circuit boards inside are all made based on copper clad laminates. In the computer field: from the motherboards and graphics cards of personal computers to the motherboards of servers, copper clad laminates are used to build complex circuit systems to achieve electrical connections between various chips, interfaces and electronic components. In the field of communications: the RF circuit boards of 5G base stations, the backplanes of communication equipment, etc. all require the use of high-performance copper clad laminates to meet the requirements of high-speed signal transmission and high reliability. In addition, copper clad laminates also play a vital role in the fields of automotive electronics, industrial control, aerospace, etc.

[0155] The present application is further described in detail below in conjunction with specific implementation methods, but the implementation methods of the present application are not limited thereto.

[0156] The sources of some of the raw materials used in each embodiment and comparative example are as follows:

[0157] Benzyltriethylammonium chloride, thionyl chloride, triethylamine: purchased from MacLean;

[0158] 4,4'-Diaminodiphenylmethane: purchased from Yuanda Chemical;

[0159] 2,5-Dicarboxylic acid benzocyclobutene: purchased from Anqing Hecheng;

[0160] Bismaleimide resin: purchased from KI Chemical, model BMI-80;

[0161] Bisphenol A cyanate: purchased from Lonza Group, model BA-230S;

[0162] Phosphate flame retardant: purchased from Daba Chemical, model PX200;

[0163] Spherical silica filler: purchased from Yaduma, model SC6500-SXD;

[0164] 2-Methylimidazole: purchased from Shikoku Chemical.

[0165] Example 1

[0166] (1) Preparation of diamine compounds

[0167] 2,5-Dicarboxylic acid benzocyclobutene (50.0 g, 0.26 mol) and benzyltriethylammonium chloride (0.25 g, 0.0011 mol) were added to 800 mL of thionyl chloride, and after being stirred evenly at room temperature, the mixture was refluxed for about 24 hours (for acyl chloride reaction) until a homogeneous solution was observed; the reaction solution was then evaporated under reduced pressure to obtain a solid, which was an acyl chloride compound;

[0168] The prepared acyl chloride compound was dissolved in 600 mL of dichloromethane and stirred vigorously; 4,4'-diaminodiphenylmethane (515.48 g, 2.6 mol) was dissolved in dichloromethane, a small amount of triethylamine was added dropwise, and mixed with the dichloromethane solution containing the acyl chloride compound. After mixing, the resulting solution was further stirred at room temperature for 12 hours. Then, the precipitate was filtered, and the obtained precipitate was washed two to three times with deionized water and dichloromethane to remove excess 4,4'-diaminodiphenylmethane, and the obtained solid was dried in a vacuum oven to obtain a diamine compound.

[0169] (2) Preparation of modified bismaleimide prepolymer

[0170] 100 parts of the diamine compound prepared in step (1), 70 parts of bismaleimide resin and 100 parts of cyclohexanone solvent were mixed uniformly by mass (the mass ratio of bismaleimide resin to diamine compound was about 1:1.43), and a prepolymerization reaction was carried out at 150° C. for 90 min, and then cooled to room temperature to obtain a modified bismaleimide prepolymer A.

[0171] (3) Preparation of resin composition

[0172] 60 parts of the modified bismaleimide prepolymer prepared in step (2) and 40 parts of bisphenol A type cyanate resin are dissolved in 80 parts of a mixed solvent in order by mass, wherein the mixed solvent comprises butanone and propylene glycol methyl ether in a mass ratio of 1:1, and the mass ratio of the modified bismaleimide prepolymer to the cyanate resin is 1:0.75; 20 parts of spherical silica, 5 parts of a phosphate flame retardant and 2 parts of 2-methylimidazole are added under stirring, and stirring is continued to obtain a uniform resin composition.

[0173] (4) Preparation of prepreg

[0174] 2116 glass fiber cloth (basic weight 105g / m 2 ) is impregnated in the resin composition prepared in step (3), and baked in a hot air circulation oven at 180° C. for 3 min to obtain a prepreg with a resin content of 50%.

[0175] (5) Preparation of copper clad laminate

[0176] The six prepregs prepared in step (4) were stacked, and a 12 μm thick electrolytic copper foil was covered on each of the upper and lower surfaces of the stacked body. The stacked body was placed in a programmable temperature and pressure controlled vacuum press and heated to 20 kgf / cm2 in a vacuum state. 2 Under pressure, it was first cured at 220℃*2h, then heated to 300℃ and continued to cure for 1h to produce a 0.6mm thick copper-clad laminate.

[0177] Example 2

[0178] The method is basically the same as Example 1, except that in step (3) of Example 2, the mass fraction of the modified bismaleimide prepolymer A is 40 parts, and the mass fraction of the bisphenol A type cyanate ester resin is 40 parts; the mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin is 1:1.

[0179] Example 3

[0180] The method is basically the same as Example 1, except that in step (3) of Example 3, the mass fraction of the modified bismaleimide prepolymer A is 80 parts, and the mass fraction of the bisphenol A type cyanate ester resin is 40 parts; the mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin is 1:0.5.

[0181] Example 4

[0182] The method is basically the same as Example 1, except that, in step (2) of Example 4, the modified bismaleimide prepolymer is prepared as follows:

[0183] 80 parts of the diamine compound prepared in step (1), 70 parts of bismaleimide resin and 100 parts of cyclohexanone solvent were mixed uniformly by mass (the mass ratio of bismaleimide resin to diamine compound was about 1:1.14), and prepolymerized at 150° C. for 90 min, and then cooled to room temperature to obtain a modified bismaleimide prepolymer B.

[0184] Example 5

[0185] The method is basically the same as Example 1, except that, in step (2) of Example 5, the modified bismaleimide prepolymer is prepared as follows:

[0186] 120 parts of the diamine compound prepared in step (1), 70 parts of bismaleimide resin and 100 parts of cyclohexanone solvent were mixed uniformly by mass (the mass ratio of bismaleimide resin to diamine compound was about 1:1.71), and a prepolymerization reaction was carried out at 150° C. for 90 min, and then cooled to room temperature to obtain a modified bismaleimide prepolymer C.

[0187] Comparative Example 1

[0188] The method is basically the same as Example 1, except that in step (3) of Example 1, the mass fraction of the modified bismaleimide prepolymer A is 120 parts, and the mass fraction of the bisphenol A type cyanate ester resin is 40 parts.

[0189] Comparative Example 2

[0190] The method is basically the same as Example 1, except that, in the step of preparing the resin composition, the modified bismaleimide prepolymer is replaced with an equal mass of bismaleimide resin, as follows:

[0191] (1) Preparation of resin composition

[0192] 60 parts of bismaleimide resin and 40 parts of bisphenol A cyanate resin are dissolved in a mixed solvent in turn, according to the mass ratio, wherein the mixed solvent includes butanone and propylene glycol methyl ether in a mass ratio of 1:1; under stirring conditions, 20 parts of spherical silica, 5 parts of phosphate flame retardant and 2 parts of 2-methylimidazole are added, and stirring is continued to obtain a uniform resin composition.

[0193] (2) Preparation of prepreg

[0194] 2116 glass fiber cloth (basic weight 105g / m 2 ) is impregnated in the resin composition prepared in step (1), and baked in a hot air circulation oven at 180° C. for 3 min to obtain a prepreg with a resin content of 50%.

[0195] (3) Preparation of copper clad laminate

[0196] The six prepregs prepared in step (2) were stacked, and a 12 μm thick electrolytic copper foil was covered on each of the upper and lower surfaces of the stacked body. The stacked body was placed in a programmable temperature and pressure controlled vacuum press and heated to 20 kgf / cm2 in a vacuum state. 2 Under pressure, it was first cured at 220℃*2h, then heated to 300℃ and continued to cure for 1h to produce a 0.6mm thick copper-clad laminate.

[0197] Comparative Example 3

[0198] The method is basically the same as Example 1, except that, in Comparative Example 3, the diamine compound in step (2) of Example 1 is replaced with an equal mass of DDS (4,4'-diaminodiphenyl sulfone) to obtain a modified bismaleimide prepolymer D, and the structure of DDS is as follows:

[0199]

[0200] Comparative Example 4

[0201] The method is basically the same as Example 1, except that in step (3), the cyanate resin is replaced with an epoxy resin of equal mass.

[0202] The components and weight fractions of the resin composition used in the copper-clad laminates prepared in the examples and comparative examples are shown in Table 1.

[0203] Table 1

[0204]

[0205] The copper-clad laminates prepared in each embodiment and comparative example were subjected to performance tests, and the test methods were as follows:

[0206] Thermal expansion coefficient (CTE), thermal expansion coefficient of copper clad laminate in X-axis and Y-axis (X / Y-CTE): tested according to IPC-TM-6502.4.24;

[0207] Glass transition temperature (Tg): Tested according to IPC-TM650 2.4.25D;

[0208] Thermal decomposition temperature (Td): Tested according to IPC-TM650 2.4.24.6;

[0209] Peel strength: The test method is carried out in accordance with IPC-TM-650 2.4.8;

[0210] Elastic modulus: tested according to GB / T 22315-2008;

[0211] Dk / Df: Tested according to IPC-TM650 2.5.5.2;

[0212] The results are shown in Table 2.

[0213] Table 2

[0214]

[0215] As can be seen from Table 2, compared with comparative example, the resin combination used in each embodiment cooperates the modified bismaleimide prepolymer and cyanate resin prepared by specific raw materials according to a specific ratio, and the copper-clad laminate finally obtained not only has a lower thermal expansion coefficient, but also has a higher glass transition temperature and thermal decomposition temperature, a higher peel strength and elastic modulus and a lower dielectric constant and dielectric loss. And the ratio of the modified bismaleimide prepolymer and cyanate resin of comparative example 1 is inappropriate, the bismaleimide of comparative example 2 is not modified by the diamine compound with a specific structure, the diamine compound in the modified bismaleimide prepolymer of comparative example 3 does not contain benzocyclobutene structure, and the modified bismaleimide prepolymer A is coordinated with epoxy resin by comparative example 4, the thermal expansion coefficient of the copper-clad laminate prepared by comparative example 1~comparative example 4 increases, and glass transition temperature, thermal decomposition temperature, glass transition temperature and thermal decomposition temperature appear to be reduced to varying degrees respectively, and dielectric constant and dielectric loss increase.

[0216] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0217] The above-described embodiments only express several implementation methods of the present application, which is convenient for understanding the technical solution of the present application in detail, but it cannot be understood as limiting the scope of protection of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent of this application shall be based on the content of the attached claims, and the description can be used to interpret the content of the claims.

Claims

1. A resin composition, characterized in that By mass, it includes the following components: 30-80 parts of modified bismaleimide prepolymer; and 20-60 parts of cyanate resin; The raw materials for preparing the modified bismaleimide prepolymer include bismaleimide resin and a diamine compound, and the diamine compound contains a benzocyclobutene structure.

2. The resin composition according to claim 1, characterized in that By mass, it includes the following components: 40-80 parts of modified bismaleimide prepolymer; and 30~50 parts of cyanate resin.

3. The resin composition according to claim 2, characterized in that By mass, it includes the following components: 60-80 parts of modified bismaleimide prepolymer; and 35-45 parts of cyanate resin.

4. The resin composition according to claim 1, characterized in that The mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin is 1:0.5-1; optionally, the mass ratio of the modified bismaleimide prepolymer to the cyanate ester resin is 1:0.5-0.

75.

5. The resin composition according to claim 1, characterized in that In the raw materials for preparing the modified bismaleimide prepolymer, the mass ratio of the bismaleimide resin to the diamine compound is 1:1-3; optionally, the mass ratio of the bismaleimide resin to the diamine compound is 1:1.4-2.

6. The resin composition according to claim 1, characterized in that The structure of the diamine compound is shown in formula (I): 。 7. The resin composition according to any one of claims 1 to 6, characterized in that The monomer of the bismaleimide resin includes at least one of N-phenylmaleimide, N-(2-methylphenyl)maleimide, N-(4-methylphenyl)maleimide, N-(2,6-dimethylphenyl)maleimide, bis(4-maleimidophenyl)methane, 2,2-bis(4-(4-maleimidophenoxy)-phenyl)propane, bis(3,5-dimethyl-4-maleimidophenyl)methane, bis(3-ethyl-5-methyl-4-maleimidophenyl)methane, bis(3,5-diethyl-4-maleimidophenyl)methane, polyphenylmethane bismaleimide, bismaleimide containing biphenyl structure and polymaleimide.

8. The resin composition according to any one of claims 1 to 6, characterized in that The cyanate resin includes at least one of bisphenol A cyanate resin, novolac cyanate resin, bisphenol F cyanate resin, multifunctional cyanate resin, bisphenol M cyanate resin, bisphenol E cyanate resin and dicyclopentadiene bisphenol cyanate resin.

9. The resin composition according to any one of claims 1 to 6, wherein The resin composition further comprises 10 to 40 parts of an inorganic filler by mass; optionally, the inorganic filler comprises at least one of zirconium vanadate, zirconium tungstate, hafnium tungstate, glass-ceramics, eucryptite, silicon dioxide, quartz, mica powder, titanium dioxide, magnesium oxide, magnesium hydroxide, talc, aluminum oxide, silicon carbide, boron nitride, aluminum nitride, molybdenum oxide, barium sulfate, zinc molybdate, zinc borate, zinc stannate, zinc oxide, strontium titanate, barium titanate, calcium titanate, clay and kaolin.

10. The resin composition according to any one of claims 1 to 6, characterized in that The resin composition further comprises 5 to 20 parts of a flame retardant by mass; optionally, the flame retardant comprises at least one of decabromodiphenylethane, tetrabromobisphenol A, brominated epoxy resin, phosphorus-containing epoxy resin, phosphorus-containing phenolic resin, phosphazene compound, phosphate ester compound and phosphorus-containing cyanate ester.

11. A method for preparing a resin composition, characterized in that: The following steps are involved: 30-80 parts of modified bismaleimide prepolymer and 20-60 parts of cyanate resin are mixed by weight; the raw materials for preparing the modified bismaleimide prepolymer include bismaleimide resin and diamine compound, and the diamine compound contains benzocyclobutene structure.

12. The method for preparing the resin composition according to claim 11, characterized in that: The preparation of the modified bismaleimide prepolymer comprises the following steps: The bismaleimide resin and the diamine compound are mixed to perform a prepolymerization reaction; optionally, the temperature of the prepolymerization reaction is 150° C. to 250° C.

13. A resin film, characterized in that: The resin film comprises the resin composition according to any one of claims 1 to 10 or a resin composition prepared by the preparation method according to any one of claims 11 to 12.

14. A prepreg, characterized in that: A resin composition comprising a reinforcing material and a resin composition as claimed in any one of claims 1 to 10 or a resin composition prepared by the preparation method as claimed in any one of claims 11 to 12 attached to the reinforcing material.

15. A laminated board, characterized in that: The method comprises at least one of the resin film according to claim 13 and the prepreg according to claim 14.

16. A method for preparing a laminate, characterized in that: The following steps are involved: At least one of the resin film according to claim 13 and the prepreg according to claim 14 is subjected to thermocompression molding.

17. The method for preparing a laminate according to claim 16, characterized in that: The hot pressing molding comprises a first hot pressing molding and a second hot pressing molding performed sequentially, wherein the temperature of the first hot pressing molding is 150°C to 250°C, and the temperature of the second hot pressing molding is 250°C to 400°C.

18. A printed circuit board, characterized in that: It comprises at least one of the resin film as claimed in claim 13, the prepreg as claimed in claim 14, the laminate as claimed in claim 15, and the laminate prepared by the method for preparing the laminate as claimed in any one of claims 16 to 17.

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