Resin composition, prepreg and preparation method therefor, and laminate and preparation method therefor

Abstract

A resin composition, a prepreg and a preparation method therefor, and a laminate and a preparation method therefor. The resin composition comprises the following raw materials in parts by mass: 20-50 parts of a modified bismaleimide prepolymer, 10-40 parts of cyanate ester resin, 30-60 parts of functional resin, and 50-200 parts of an inorganic filler, wherein raw materials of the modified bismaleimide prepolymer include bismaleimide resin and a modifier, and the modifier comprises tripolynaphthalene diallyl ether. A cured product of the resin composition has an extremely low coefficient of thermal expansion, excellent high-temperature modulus retention and extremely high heat resistance, also shows excellent dielectric properties, and is thus suitable for preparing high-performance semiconductor packaging substrates.

Description

Resin composition, prepreg and preparation method thereof, and laminate and preparation method thereof Technical Field

[0001] The present invention relates to the technical field of modified resins, in particular to a resin composition, a prepreg and a preparation method thereof, and a laminate and a preparation method thereof. Background Art

[0002] In recent years, the trend toward miniaturization and multifunctionality in electronic devices has driven demand for semiconductor package substrates to be thinner, lighter, and more highly integrated. Furthermore, they are required to possess high glass transition temperatures, high modulus, and low thermal expansion coefficients to ensure reliable interconnection and installation. Furthermore, with the advent of the artificial intelligence (AI) era, the volume and speed of information processing are exploding, necessitating semiconductor package substrates with lower dielectric constants and dielectric loss to minimize transmission losses.

[0003] Currently, most semiconductor packaging substrates use BT substrates, a type of resin-based packaging substrate formed by heat curing with bismaleimide (BMI) and cyanate ester resin (also known as triazine A, TA) as the main resin components. However, traditional BT substrates struggle to meet the high-performance demands of the AI ​​era in terms of thermal expansion coefficient, heat resistance, and dielectric properties.

[0004] Summary of the Invention

[0005] Based on this, it is necessary to provide a resin composition, a prepreg and a preparation method thereof, and a laminate and a preparation method thereof to overcome the problem that traditional BT carrier boards are difficult to meet the demand for high-performance carrier boards in the AI ​​era in terms of thermal expansion coefficient, heat resistance and dielectric properties.

[0006] The above-mentioned object of the present invention is achieved through the following technical solutions:

[0007] In a first aspect of the present invention, a resin composition is provided, comprising the following raw materials in parts by weight:

[0008] The raw materials of the modified bismaleimide prepolymer include bismaleimide resin and a modifier, and the modifier includes terphenyl naphthalene bisallyl ether.

[0009] In one embodiment, in the raw materials of the modified bismaleimide prepolymer, the mass ratio of the bismaleimide resin to the terpolymer naphthalene bisallyl ether is 100:(60-100).

[0010] In one embodiment, the modifier further comprises one or more of diallyl bisphenol A, diallyl bisphenol S, diallyl bisphenol F and bisphenol A bisallyl ether.

[0011] In one embodiment, the bismaleimide resin includes one or more of N,N'-(4,4'-methylenediphenyl)bismaleimide, N,N'-(1,4-phenylene)bismaleimide, N,N'-(4-methyl-1,3-phenylene)bismaleimide, N,N'-m-phenylene bismaleimide, 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 and bismaleimide containing biphenyl structure.

[0012] In one embodiment, the method for preparing the modified bismaleimide prepolymer comprises the following steps:

[0013] The modifier is heated to be melted, and the bismaleimide resin is added thereto to carry out a prepolymerization reaction to prepare the modified bismaleimide prepolymer.

[0014] In one embodiment, the temperature of the prepolymerization reaction is 140° C. to 170° C.;

[0015] In one embodiment, the prepolymerization reaction time is 60 min to 180 min.

[0016] In one embodiment, the cyanate ester resin includes one or more of bisphenol A cyanate ester resin, novolac cyanate ester resin, bisphenol F cyanate ester resin, bisphenol M cyanate ester resin, bisphenol E cyanate ester resin, naphthalene cyanate ester resin, biphenyl cyanate ester resin, bisphenol S cyanate ester resin and dicyclopentadiene bisphenol cyanate ester resin.

[0017] In one embodiment, the functional resin includes one or more of benzoxazine resin, modified polyphenylene ether resin and hydrocarbon resin.

[0018] In one embodiment, the benzoxazine resin includes one or more of bisphenol A benzoxazine resin, bisphenol F benzoxazine resin, bisphenol S benzoxazine resin, main chain benzoxazine resin, phosphorus-containing benzoxazine resin, dicyclopentadiene benzoxazine resin, biphenyl benzoxazine resin, tetraphenol ethane benzoxazine resin and naphthalene benzoxazine resin.

[0019] In one embodiment, the modified polyphenylene ether resin has a structure as shown in formula (II):

[0020] Wherein, m and n are both positive integers, and the sum of m and n is 5 to 60;

[0021] Y is absent or selected from an alkylene group having 1 to 3 carbon atoms.

[0022] In one embodiment, the hydrocarbon resin includes one or more of polybutadiene and styrene-butadiene copolymer.

[0023] In one embodiment, the inorganic filler includes one or more of zirconium vanadate, zirconium tungstate, hafnium tungstate, microcrystalline glass, eucryptite, silica, 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.

[0024] In one embodiment, the resin composition further comprises one or more of a flame retardant, a curing accelerator, a solvent and an auxiliary agent, and the auxiliary agent comprises one or more of a dispersant, a defoaming agent, a leveling agent, a coupling agent, a surfactant and a UV absorber.

[0025] A second aspect of the present invention provides a method for preparing a prepreg, comprising the following steps:

[0026] The resin composition is covered on the surface of the reinforcing material and semi-cured to prepare the prepreg.

[0027] In one embodiment, the method of covering the resin composition on the surface of the reinforcing material includes one or more of an impregnation method, a padding method, and a coating method.

[0028] In one embodiment, the reinforcing material includes one or more of an inorganic fiber material and an organic fiber material.

[0029] In one embodiment, the temperature of the semi-curing treatment is 120°C to 230°C.

[0030] In one embodiment, the semi-curing treatment time is 3 minutes to 15 minutes.

[0031] According to a third aspect of the present invention, a prepreg is provided, wherein the raw materials of the prepreg include a reinforcing material and the resin composition described above, or the prepreg is prepared by the method for preparing the prepreg described above.

[0032] In a fourth aspect, the present invention provides a laminate, the raw materials of which include the prepreg described above.

[0033] In one embodiment, one or both sides of the laminate are coated with metal foil.

[0034] In one embodiment, the metal foil comprises copper foil.

[0035] In one embodiment, the thickness of the metal foil is 3 μm to 105 μm.

[0036] In a fifth aspect, the present invention provides a method for preparing the laminated board described above, comprising the following steps:

[0037] The prepreg is subjected to vacuum hot pressing treatment.

[0038] In one embodiment, the temperature of the vacuum hot pressing treatment is 150°C to 300°C.

[0039] In one embodiment, the pressure of the vacuum hot pressing treatment is 10 kgf / cm 2 ~50kgf / cm 2 .

[0040] In one embodiment, the vacuum degree of the vacuum hot pressing treatment is ≤2kPa.

[0041] In one embodiment, the vacuum hot pressing treatment lasts for 200 to 400 minutes.

[0042] The present invention has the following beneficial effects:

[0043] In the resin combination provided by the invention, a modified bismaleimide prepolymer is prepared using a bismaleimide resin and a properties-correcting agent including trimerized naphthalene bisallyl ether, wherein trimerized naphthalene bisallyl ether can introduce multiple high-rigidity naphthalene ring structures in the molecular structure of the modified bismaleimide prepolymer, not only can its structural symmetry be reduced to promote the compatibility of the prepolymer with other resins, but also is conducive to reducing the thermal expansion coefficient, and improving glass transition temperature, high-temperature modulus and dielectric properties. The modified bismaleimide prepolymer is coordinated with components such as cyanate resin, functional resin and inorganic filler with a specific ratio, so that the cured product of the resin combination has extremely low thermal expansion coefficient, excellent high-temperature modulus retentivity and extremely high heat resistance, while also showing excellent dielectric properties, and is suitable for preparing high-performance semiconductor package carriers. DETAILED DESCRIPTION

[0044] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0047] BT substrates are a type of resin-based packaging substrate, formed by heat curing with bismaleimide (BMI) and cyanate ester (TA) resins as their primary resin components. They exhibit high glass transition temperature (Tg), excellent dielectric properties, and a low coefficient of thermal expansion (CTE). However, their dielectric properties are less than ideal, with a dielectric constant (Dk) of 4.3 and a dielectric loss factor (Df) of 0.008, making them unable to meet the explosive growth in information processing volume and speed required in the AI ​​era.

[0048] Among them, bismaleimide resin has excellent heat resistance and thermal stability, low curing shrinkage, low thermal expansion coefficient, and good dielectric properties, making it a commonly used resin matrix in semiconductor packaging substrates. Unmodified bismaleimide has disadvantages such as poor solubility, too high curing temperature, too high cross-linking density and excessive brittleness of the cured product due to the high symmetry of its structure. It is difficult to use alone and usually needs to be modified before use. Modified bismaleimide resin is often used in traditional technology to prepare BT substrates, but it still has defects such as high thermal expansion coefficient, poor heat resistance and high dielectric loss, making it difficult to use in high-end integrated circuits in the AI ​​era.

[0049] Based on this, the first aspect of the present invention provides a resin composition that effectively solves the problem that traditional BT carriers are difficult to meet the demand for high-performance carriers in the AI ​​era in terms of thermal expansion coefficient, heat resistance and dielectric properties.

[0050] In some embodiments, the resin composition includes the following raw materials in parts by weight:

[0051] The raw materials of the modified bismaleimide prepolymer include bismaleimide resin and a modifier, and the modifier includes terphenyl naphthalene bisallyl ether.

[0052] It can be understood that terpolymer naphthalene bisallyl ether has a structure as shown in the general formula (I):

[0053] In the resin combination provided by the invention, a modified bismaleimide prepolymer is prepared using a bismaleimide resin and a properties-correcting agent including trimerized naphthalene bisallyl ether, wherein trimerized naphthalene bisallyl ether can introduce multiple high-rigidity naphthalene ring structures in the molecular structure of the modified bismaleimide prepolymer, not only can its structural symmetry be reduced to promote the compatibility of the prepolymer with other resins, but also is conducive to reducing the thermal expansion coefficient, and improving glass transition temperature, high-temperature modulus and dielectric properties. The modified bismaleimide prepolymer is coordinated with components such as cyanate resin, functional resin and inorganic filler with a specific ratio, so that the cured product of the resin combination has extremely low thermal expansion coefficient, excellent high-temperature modulus retentivity and extremely high heat resistance, while also showing excellent dielectric properties, and is suitable for preparing high-performance semiconductor package carriers.

[0054] It is understood that in the resin composition, the weight percentage of the modified bismaleimide prepolymer includes, but is not limited to, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, and 50 parts. Preferably, the weight percentage of the modified bismaleimide prepolymer is 20 to 40 parts. More preferably, the weight percentage of the modified bismaleimide prepolymer in the resin composition is 25 to 35 parts.

[0055] It is understood that in the resin composition, the mass fraction of the cyanate ester resin includes, but is not limited to, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, and 40 parts. Preferably, the mass fraction of the cyanate ester resin is 10 to 30 parts. More preferably, the mass fraction of the cyanate ester resin in the resin composition is 15 to 25 parts.

[0056] It is understood that in the resin composition, the weight percentage of the functional resin includes, but is not limited to, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, and 60 parts. Preferably, the weight percentage of the functional resin is 30 to 50 parts. More preferably, the weight percentage of the functional resin is 35 to 45 parts.

[0057] It is understood that in the resin composition, the mass percentage of the inorganic filler includes, but is not limited to, 50 parts, 60 parts, 70 parts, 80 parts, 90 parts, 100 parts, 110 parts, 120 parts, 130 parts, 140 parts, 150 parts, 160 parts, 170 parts, 180 parts, 190 parts, and 200 parts. Preferably, the mass percentage of the inorganic filler is 80 to 160 parts. More preferably, the mass percentage of the inorganic filler is 100 to 140 parts.

[0058] Preferably, the resin composition comprises the following raw materials in parts by mass:

[0059] More preferably, the resin composition comprises the following raw materials in parts by mass:

[0060] Optionally, in the raw materials of the modified bismaleimide prepolymer, the mass ratio of bismaleimide resin to terpolymer naphthalene bisallyl ether is 100:(60-100), for example, 100:60, 100:65, 100:70, 100:75, 100:80, 100:85, 100:90, 100:95, or 100:100. Controlling the mass ratio of bismaleimide resin to terpolymer naphthalene bisallyl ether can regulate the naphthalene ring content in the modified bismaleimide prepolymer, thereby improving its compatibility, thermal expansion coefficient, glass transition temperature, and dielectric properties.

[0061] It is understandable that when using a modifier to modify the bismaleimide resin, trimeryl naphthalene bisallyl ether can be used alone or in combination with a traditional bismaleimide resin modifier, and the combination ratio is not limited.

[0062] Optionally, the modifier further comprises one or more of diallyl bisphenol A, diallyl bisphenol S, diallyl bisphenol F, and bisphenol A bisallyl ether. Preferably, the modifier is selected from at least one of the following combinations: trimerized naphthalene bisallyl ether and diallyl bisphenol A; trimerized naphthalene bisallyl ether and diallyl bisphenol S; trimerized naphthalene bisallyl ether and diallyl bisphenol F; trimerized naphthalene bisallyl ether and diallyl bisphenol F.

[0063] It is understood that the bismaleimide resin is selected from organic compounds containing at least two maleimide groups in the molecular structure. Optionally, the bismaleimide resin includes one or more of N,N'-(4,4'-methylenediphenyl)bismaleimide, N,N'-(1,4-phenylene)bismaleimide, N,N'-(4-methyl-1,3-phenylene)bismaleimide, N,N'-m-phenylene bismaleimide, 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 and bismaleimide containing a biphenyl structure.

[0064] In some embodiments, the method for preparing the modified bismaleimide prepolymer comprises the following steps:

[0065] The modifier is heated to be melted, and bismaleimide resin is added to carry out prepolymerization reaction to prepare modified bismaleimide prepolymer.

[0066] Optionally, the modifier is heated to a melting temperature of 100° C. to 150° C., including but not limited to 100° C., 105° C., 110° C., 115° C., 120° C., 125° C., 130° C., 135° C., 140° C., 145° C., and 150° C. Preferably, the modifier is heated to a melting temperature of 100° C. to 130° C.

[0067] Optionally, the temperature of the prepolymerization reaction is 140° C. to 170° C., including but not limited to 140° C., 145° C., 150° C., 155° C., 160° C., 165° C., and 170° C. Preferably, the temperature of the prepolymerization reaction is 140° C. to 160° C. More preferably, the temperature of the prepolymerization reaction is 145° C. to 155° C.

[0068] Optionally, after the prepolymerization reaction, a step of cooling to room temperature is further included.

[0069] Optionally, the prepolymerization reaction time is 60 min to 180 min, including but not limited to: 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. Preferably, the prepolymerization reaction time is 80 min to 150 min. More preferably, the prepolymerization reaction time is 90 min to 120 min.

[0070] In some embodiments, the cyanate ester resin includes one or more of bisphenol A cyanate ester resin, novolac cyanate ester resin, bisphenol F cyanate ester resin, bisphenol M cyanate ester resin, bisphenol E cyanate ester resin, naphthalene cyanate ester resin, biphenyl cyanate ester resin, bisphenol S cyanate ester resin, and dicyclopentadiene bisphenol cyanate ester resin.

[0071] In some embodiments, the functional resin includes one or more of a benzoxazine resin, a modified polyphenylene ether resin, and a hydrocarbon resin.

[0072] Hydrocarbon resins, with their excellent dielectric properties, are widely used in electronic devices. However, their flexible, non-polar carbon chain structure leads to problems with the cured product, such as insufficient rigidity, low strength, poor heat resistance, and a low glass transition temperature. Furthermore, they exhibit poor compatibility with the highly polar bismaleimide resin. Polyphenylene oxide (PPO) resins, with their molecular structure containing numerous benzene rings and lacking strongly polar groups, possess excellent properties such as a high glass transition temperature, low linear expansion coefficient, low dielectric constant, and low dielectric loss. Modification of PPO resins by introducing unsaturated groups such as alkenyl, alkynyl, or acrylate groups can improve compatibility and reduce melt viscosity. Benzoxazine resin refers to an organic compound containing a six-membered oxazine ring in its molecular structure. It has high heat resistance, a glass transition temperature above 150°C, and a curing shrinkage rate of almost 0. It has good flame retardancy, low water absorption, good elastic modulus, and a small dielectric constant, but it is brittle and has a high curing temperature.

[0073] Among the functional resins mentioned above, the dielectric properties, from highest to lowest, are hydrocarbon resin, modified polyphenylene ether resin, and benzoxazine resin. By combining different functional resin components, the number of polar groups in the cured product of the resin composition can be significantly reduced, thereby effectively improving its dielectric properties.

[0074] It is understood that the functional resin may be selected from only one of benzoxazine resin, modified polyphenylene ether resin, and hydrocarbon resin, or may be selected from at least two of the group consisting of benzoxazine resin, modified polyphenylene ether resin, and hydrocarbon resin. Preferably, the functional resin includes benzoxazine resin and modified polyphenylene ether resin.

[0075] Optionally, the benzoxazine resin includes one or more of bisphenol A-type benzoxazine resin, bisphenol F-type benzoxazine resin, bisphenol S-type benzoxazine resin, main chain benzoxazine resin, phosphorus-containing benzoxazine resin, dicyclopentadiene benzoxazine resin, biphenyl-type benzoxazine resin, tetraphenolethane benzoxazine resin and naphthalene-type benzoxazine resin.

[0076] Optionally, the modified polyphenylene ether resin has a structure as shown in general formula (II):

[0077] Wherein, m and n are both positive integers, and the sum of m and n is 5 to 60;

[0078] Y is absent or selected from an alkylene group having 1 to 3 carbon atoms.

[0079] Optionally, the hydrocarbon resin includes one or more of polybutadiene and styrene-butadiene copolymer. Preferably, the hydrocarbon resin is polybutadiene.

[0080] In some embodiments, the inorganic filler includes one or more of zirconium vanadate, zirconium tungstate, hafnium tungstate, glass-ceramics, eucryptite, silicon dioxide, 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. Among them, silicon dioxide can be at least one of spherical silica, fused silica, and composite silica. Preferably, the inorganic filler is spherical silica.

[0081] Adding a suitable inorganic filler to the resin composition can play a synergistic role with the modified maleimide prepolymer and significantly reduce the thermal expansion coefficient of the resin composition.

[0082] In some embodiments, the resin composition further comprises one or more of a flame retardant, a curing accelerator, a solvent and an auxiliary agent, and the auxiliary agent comprises one or more of a dispersant, a defoaming agent, a leveling agent, a coupling agent, a surfactant and a UV absorber.

[0083] Among them, adding a flame retardant can improve the flame retardancy of the resin composition. Adding a curing accelerator can reduce the curing temperature of the resin composition and accelerate the curing speed, thereby reducing the processing difficulty of the resin composition. Adding a solvent can improve the compatibility between the various components and avoid the undesirable phenomenon of stratification or precipitation. Adding an auxiliary agent can improve the dispersibility, fluidity, uniformity and bonding ability between different components of the resin composition, and improve the curing ability of the resin composition, thereby enhancing the various properties of its cured product.

[0084] Optionally, the resin composition further comprises the following raw materials in parts by mass:

[0085] It is understood that in the resin composition, the mass fraction of the flame retardant includes, but is not limited to, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, and 40 parts. Preferably, the mass fraction of the flame retardant is 10 to 30 parts. More preferably, the mass fraction of the flame retardant is 15 to 25 parts.

[0086] It is understood that in the resin composition, the mass fraction of the curing accelerator includes, but is not limited to, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, and 10 parts. Preferably, the mass fraction of the curing accelerator is 2 to 8 parts. More preferably, the mass fraction of the curing accelerator is 4 to 6 parts.

[0087] It is understood that in the resin composition, the mass parts of the solvent include, but are not limited to, 50 parts, 60 parts, 70 parts, 80 parts, 90 parts, 100 parts, 110 parts, 120 parts, 130 parts, 140 parts, and 150 parts. Preferably, the mass parts of the solvent are 80 parts to 120 parts. More preferably, the mass parts of the solvent are 90 parts to 110 parts.

[0088] It is understood that in the resin composition, the weight percentage of the auxiliary agent includes, but is not limited to, 1 part, 2 parts, 3 parts, 4 parts, and 5 parts. Preferably, the weight percentage of the auxiliary agent is 2 to 4 parts. More preferably, the weight percentage of the auxiliary agent is 3 parts.

[0089] Optionally, the flame retardant includes one or more of a halogenated flame retardant and a halogen-free flame retardant. The halogenated flame retardant includes one or more of ethylenebispentabromobenzene, decabromodiphenylethane, tetrabromobisphenol A, ethylenebistetrabromoimide, and tetradecabromodiphenoxybenzene; and the halogen-free flame retardant includes one or more of a phosphazene compound, a phosphate compound, a bisdiphenylphosphine oxide compound, and a phosphinate compound.

[0090] Optionally, the curing accelerator includes one or more of a tertiary amine accelerator, an imidazole accelerator, a peroxide accelerator, an organophosphorus accelerator, and a transition metal carboxylate accelerator. Tertiary amine accelerators include, but are not limited to, tris(dimethylaminomethyl)phenol, triethylenediamine, and dimethylaniline; imidazole accelerators include, but are not limited to, 2-methylimidazole, 2-ethylimidazole, and 2-ethyl-4-methylimidazole; peroxide accelerators include, but are not limited to, dicumyl peroxide, tert-butyl perbenzoate, and tert-butyl peroxyoctanoate; and transition metal carboxylate accelerators include, but are not limited to, cobalt acetylacetonate, nickel acetylacetonate, and zinc acetylacetonate. Organophosphorus accelerators include, but are not limited to, triphenylphosphine.

[0091] Optionally, the solvent includes one or more of ethanol, acetone, cyclohexanone, butanone, toluene, xylene, N,N-dimethylformamide, N,N-dimethylacetamide, and propylene glycol methyl ether. Preferably, the solvent includes butanone, toluene, and propylene glycol methyl ether. More preferably, the mass ratio of butanone, toluene, and propylene glycol methyl ether in the solvent is 1:1:1.

[0092] Optionally, the coupling agent includes one or more of a silane coupling agent, a titanate coupling agent, and a zirconate coupling agent. Preferably, the coupling agent is a silane coupling agent.

[0093] In a second aspect, the present invention provides a method for preparing a prepreg, which uses the resin composition described above.

[0094] In some embodiments, the method for preparing the prepreg comprises the following steps:

[0095] The resin composition is covered on the surface of the reinforcing material and semi-cured to prepare a prepreg.

[0096] It can be understood that prepreg, also known as semi-cured sheet, is a composition of a resin matrix / reinforcement material combination formed by compounding a resin matrix and a reinforcement material (continuous fiber, fabric or chopped fiber). It is a material form for manufacturing advanced composite components.

[0097] Optionally, the method of covering the surface of the reinforcing material with the resin composition includes one or more of a dipping method, a padding method, and a coating method. Preferably, the method of covering the surface of the reinforcing material with the resin composition is a dipping method.

[0098] Optionally, the reinforcing material includes one or more of an inorganic fiber material and an organic fiber material. The inorganic fiber material includes one or more of glass fiber, carbon fiber, silicon carbide fiber, and asbestos fiber; the glass fiber includes one or more of E-glass fiber, NE-glass fiber, D-glass fiber, S-glass fiber, and T-glass fiber. The organic fiber material includes one or more of nylon fiber, polyethylene fiber, aramid fiber, polyimide fiber, polyester fiber, and cotton fiber; and the polyethylene fiber includes one or more of high-density polyethylene (HDPE) fiber, low-density polyethylene (LDPE) fiber, linear low-density polyethylene (LLDPE) fiber, and ultra-high molecular weight polyethylene (UHMWPE) fiber.

[0099] Optionally, the temperature of the semi-curing treatment is 120° C. to 230° C., including but not limited to 120° C., 130° C., 140° C., 150° C., 160° C., 170° C., 180° C., 190° C., 200° C., 210° C., 220° C., and 230° C. Preferably, the temperature of the semi-curing treatment is 140° C. to 180° C. More preferably, the temperature of the semi-curing treatment is 150° C. to 170° C.

[0100] Optionally, the semi-curing treatment time is 3 minutes to 15 minutes, including but not limited to: 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, and 15 minutes. Preferably, the semi-curing treatment time is 3 minutes to 10 minutes. More preferably, the semi-curing treatment time is 4 minutes to 8 minutes.

[0101] According to a third aspect of the present invention, a prepreg is provided, wherein the raw materials of the prepreg include a reinforcing material and the resin composition described above, or the prepreg is prepared by the method for preparing the prepreg described above.

[0102] In a fourth aspect, the present invention provides a laminate, the raw materials of which include the prepreg described above.

[0103] It can be understood that the raw materials of the laminate include one or more prepregs.

[0104] Optionally, the laminate is coated with metal foil on one or both sides.

[0105] Optionally, the metal foil comprises copper foil;

[0106] Optionally, the thickness of the metal foil is 3 μm to 105 μm, including but not limited to: 3 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, and 105 μm.

[0107] In a fifth aspect, the present invention provides a method for preparing the laminated board described above, comprising the following steps:

[0108] The prepreg is subjected to vacuum hot pressing treatment.

[0109] Optionally, the temperature of the vacuum hot pressing treatment is 150℃~300℃, including but not limited to: 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 230℃, 240℃, 250℃, 260℃, 270℃, 280℃, 290℃, 300℃.

[0110] Optionally, the pressure of the vacuum hot pressing process is 10 kgf / cm 2 ~50kgf / cm 2 , including but not limited to: 10kgf / cm 2 、20kgf / cm 2 、30kgf / cm 2 、40kgf / cm 2 、50kgf / cm 2 .

[0111] Optionally, the vacuum degree of the vacuum hot pressing treatment is ≤2kPa, including but not limited to: 2kPa, 1.5kPa, 1kPa, 0.5kPa, 0.2kPa, 0.1kPa, 0.05kPa, 0.02kPa, 0.01kPa, 0.001kPa.

[0112] Optionally, the time of vacuum hot pressing treatment is 200min to 400min, including but not limited to: 200min, 220min, 240min, 260min, 280min, 300min, 320min, 340min, 360min, 380min, and 400min.

[0113] The present invention is further described in detail below with reference to specific embodiments.

[0114] In the following specific examples and comparative examples, the raw materials used, unless otherwise specified, are all commercially available products; the instruments used, unless otherwise specified, are all commercially available products; and the processes used, unless otherwise specified, are all routinely selected by those skilled in the art. The sources of some of the raw materials are as follows:

[0115] Tripolynaphthalene bisallyl ether: purchased from Kungang New Materials;

[0116] Bismaleimide resin: purchased from Yamato Chemical Industry, model number is BMI-5100, chemical name is bis(3-ethyl-5-methyl-4-maleimidophenyl)methane.

[0117] Bisphenol A cyanate ester resin: purchased from Lonza Group, model BA-230S;

[0118] Modified polyphenylene ether resin: purchased from Sabic, model number SA9000;

[0119] Polybutadiene: purchased from Caoda Chemical, model B1000;

[0120] Flame retardant: purchased from Daba Chemical, model PX-200, which is an organic phosphate halogen-free flame retardant;

[0121] Spherical silica: purchased from Yaduma, model number SO-E6;

[0122] Diallyl bisphenol A: purchased from Honghu Shuangma Resin Factory;

[0123] Dicumyl peroxide: purchased from Dow Chemical;

[0124] Additive: purchased from Dow Corning, model number is Z-6011, which is a silane coupling agent.

[0125] Example 1

[0126] (1) Preparation of modified bismaleimide prepolymer: Please refer to Table 1. In parts by mass, 60 parts of tri-naphthalene bisallyl ether were heated to a molten state at 120°C, 100 parts of bismaleimide resin were added, and prepolymerization was carried out at 150°C. After 90 minutes, the mixture was cooled to room temperature to obtain a modified bismaleimide prepolymer, which was recorded as prepolymer A.

[0127] Table 1. Prepolymer formulation

[0128] (2) Preparation of resin composition: Please refer to Table 2. In parts by mass, 20 parts of prepolymer A, 10 parts of bisphenol A cyanate resin, 15 parts of modified polyphenylene ether resin, 15 parts of polybutadiene and 10 parts of flame retardant are dissolved in 80 parts of solvent (a mixture of butanone, toluene and propylene glycol methyl ether in a mass ratio of 1:1:1) to obtain a mixed solution; 80 parts of spherical silica, 1 part of auxiliary agent and 1 part of diisopropylbenzene peroxide are added to the mixed solution under stirring, and stirring is continued until the mixture is uniform to obtain a resin composition in a colloidal liquid.

[0129] Table 2. Resin composition formula

[0130] (3) Preparation of prepreg: 2116 type glass fiber cloth was impregnated in the resin composition, placed in a hot air circulation oven, and baked at 160°C for 5 minutes to obtain a semi-cured sheet (i.e., prepreg).

[0131] (4) Preparation of laminate: 8 prepregs were stacked to obtain a laminate; a 12 μm thick electrolytic copper foil was placed on each of the upper and lower sides of the laminate, and the laminate was placed in a programmable temperature and pressure controlled vacuum press under a vacuum state of ≤2 kPa and a pressure of 28 kgf / cm 2 The copper clad laminate was prepared by vacuum hot pressing at 180°C for 2 h and vacuum hot pressing at 220°C for 2 h under pressure of 100°C.

[0132] Example 2

[0133] (1) Preparation of modified bismaleimide prepolymer: the same as in Example 1, namely prepolymer A.

[0134] (2) Preparation of resin composition: Please refer to Table 2. In parts by mass, 30 parts of prepolymer A, 20 parts of bisphenol A cyanate resin, 20 parts of modified polyphenylene ether resin, 20 parts of polybutadiene and 20 parts of flame retardant are dissolved in 100 parts of solvent (a mixture of butanone, toluene and propylene glycol methyl ether in a mass ratio of 1:1:1) to obtain a mixed solution; 120 parts of spherical silica, 3 parts of auxiliary agent and 5 parts of diisopropylbenzene peroxide are added to the mixed solution under stirring, and stirring is continued until the mixture is uniform to obtain a resin composition in the form of a glue.

[0135] (3) Preparation of prepreg: same as in Example 1.

[0136] (4) Preparation of laminate: same as in Example 1.

[0137] Example 3

[0138] (1) Preparation of modified bismaleimide prepolymer: the same as in Example 1, namely prepolymer A.

[0139] (2) Preparation of resin composition: Please refer to Table 2. In parts by mass, 40 parts of prepolymer A, 30 parts of bisphenol A cyanate resin, 25 parts of modified polyphenylene ether resin, 25 parts of polybutadiene and 30 parts of flame retardant are dissolved in 120 parts of solvent (a mixture of butanone, toluene and propylene glycol methyl ether in a mass ratio of 1:1:1) to obtain a mixed solution; 160 parts of spherical silica, 5 parts of auxiliary agent and 10 parts of diisopropylbenzene peroxide are added to the mixed solution under stirring, and stirring is continued until the mixture is uniform to obtain a resin composition in a colloidal liquid.

[0140] (3) Preparation of prepreg: same as in Example 1.

[0141] (4) Preparation of laminate: same as in Example 1.

[0142] Example 4

[0143] (1) Preparation of modified bismaleimide prepolymer: Please refer to Table 1. In parts by mass, 100 parts of tripolynaphthalene bisallyl ether were heated at 120°C to a molten state, 100 parts of bismaleimide resin were added, and prepolymerization was carried out at 150°C. After 120 minutes, the mixture was cooled to room temperature to obtain a modified bismaleimide prepolymer, which was recorded as prepolymer B.

[0144] (2) Preparation of resin composition: Please refer to Table 2. In parts by mass, 30 parts of prepolymer B, 15 parts of bisphenol A cyanate resin, 20 parts of modified polyphenylene ether resin, 20 parts of polybutadiene and 20 parts of flame retardant are dissolved in 100 parts of solvent (a mixture of butanone, toluene and propylene glycol methyl ether in a mass ratio of 1:1:1) to obtain a mixed solution; 120 parts of spherical silica, 3 parts of auxiliary agent and 5 parts of diisopropylbenzene peroxide are added to the mixed solution under stirring, and stirring is continued until the mixture is uniform to obtain a colloidal resin composition.

[0145] (3) Preparation of prepreg: same as in Example 1.

[0146] (4) Preparation of laminate: same as in Example 1.

[0147] Example 5

[0148] (1) Preparation of modified bismaleimide prepolymer: Please refer to Table 1. In parts by mass, 80 parts of tert-naphthalene bisallyl ether were heated to a molten state at 120°C, 100 parts of bismaleimide resin were added, and prepolymerization was carried out at 150°C. After 100 minutes, the mixture was cooled to room temperature to obtain a modified bismaleimide prepolymer, which was recorded as prepolymer C.

[0149] (2) Preparation of resin composition: Please refer to Table 2. In parts by mass, 30 parts of prepolymer C, 20 parts of bisphenol A cyanate resin, 20 parts of modified polyphenylene ether resin, 20 parts of polybutadiene and 20 parts of flame retardant are dissolved in 100 parts of solvent (a mixture of butanone, toluene and propylene glycol methyl ether in a mass ratio of 1:1:1) to obtain a mixed solution; 120 parts of spherical silica, 3 parts of auxiliary agent and 5 parts of diisopropylbenzene peroxide are added to the mixed solution under stirring, and stirring is continued until the mixture is uniform to obtain a resin composition in the form of a glue.

[0150] (3) Preparation of prepreg: same as in Example 1.

[0151] (4) Preparation of laminate: same as in Example 1.

[0152] Example 6

[0153] (1) Preparation of modified bismaleimide prepolymer: Please refer to Table 1. In parts by mass, 60 parts of tris-naphthalene bisallyl ether and 20 parts of diallyl bisphenol A were heated to a molten state at 130°C, 100 parts of bismaleimide resin were added, and prepolymerization was carried out at 150°C. After 120 minutes, the mixture was cooled to room temperature to obtain a modified bismaleimide prepolymer, which was recorded as prepolymer D.

[0154] (2) Preparation of resin composition: Please refer to Table 2. In parts by mass, 30 parts of prepolymer C, 40 parts of bisphenol A cyanate resin, 20 parts of modified polyphenylene ether resin, 20 parts of polybutadiene and 20 parts of flame retardant are dissolved in 100 parts of solvent (a mixture of butanone, toluene and propylene glycol methyl ether in a mass ratio of 1:1:1) to obtain a mixed solution; 120 parts of spherical silica, 3 parts of auxiliary agent and 5 parts of diisopropylbenzene peroxide are added to the mixed solution under stirring, and stirring is continued until the mixture is uniform to obtain a colloidal resin composition.

[0155] (3) Preparation of prepreg: same as in Example 1.

[0156] (4) Preparation of laminate: same as in Example 1.

[0157] Comparative Example 1

[0158] (1) Preparation of modified bismaleimide prepolymer: Please refer to Table 1. In parts by mass, 80 parts of diallyl bisphenol A were heated at 100°C to a molten state, 100 parts of bismaleimide resin were added, and prepolymerization was carried out at 150°C. After 120 minutes, the mixture was cooled to room temperature to obtain a modified bismaleimide prepolymer, which was recorded as prepolymer E.

[0159] (2) Preparation of resin composition: Please refer to Table 2. In parts by mass, 30 parts of prepolymer C, 20 parts of bisphenol A cyanate resin, 20 parts of modified polyphenylene ether resin, 20 parts of polybutadiene and 20 parts of flame retardant are dissolved in 100 parts of solvent (a mixture of butanone, toluene and propylene glycol methyl ether in a mass ratio of 1:1:1) to obtain a mixed solution; 120 parts of spherical silica, 3 parts of auxiliary agent and 5 parts of diisopropylbenzene peroxide are added to the mixed solution under stirring, and stirring is continued until the mixture is uniform to obtain a resin composition in the form of a glue.

[0160] (3) Preparation of prepreg: same as in Example 1.

[0161] (4) Preparation of laminate: same as in Example 1.

[0162] Comparative Example 2

[0163] (1) Preparation of resin composition: Please refer to Table 2. In parts by mass, 30 parts of unmodified bismaleimide resin, 20 parts of bisphenol A cyanate resin, 20 parts of modified polyphenylene ether resin, 20 parts of polybutadiene and 20 parts of flame retardant are dissolved in 100 parts of solvent (a mixture of butanone, toluene and propylene glycol methyl ether in a mass ratio of 1:1:1) to obtain a mixed solution; 120 parts of spherical silica, 3 parts of auxiliary agent and 5 parts of diisopropylbenzene peroxide are added to the mixed solution under stirring, and stirring is continued until the mixture is uniform to obtain a colloidal resin composition.

[0164] (2) Preparation of prepreg: same as in Example 1.

[0165] (3) Preparation of laminate: same as in Example 1.

[0166] Test Case

[0167] The resin composition and laminate were tested as follows. The results are shown in Table 3.

[0168] (1) Resin compatibility: Let it stand for one day and visually observe whether there is any precipitation or stratification;

[0169] (2) Peel strength: The test method is carried out in accordance with IPC-TM-650 2.4.8;

[0170] (3) Glass transition temperature (Tg) and high temperature modulus: tested according to IPC-TM650 2.4.25D;

[0171] (4) Coefficient of thermal expansion (XYZ-CTE): Tested according to IPC-TM650 2.4.24;

[0172] (5) Dielectric performance test: according to IPC-TM650 2.5.5.2 test;

[0173] (6) Flame retardant grade: tested according to IPC-TM650 2.3.10.

[0174] Table 3. Comparison of properties of resin compositions and laminates

[0175] As shown in Table 3, Comparative Example 2, which uses an unmodified bismaleimide resin, exhibits precipitation in the resin composition, resulting in poor compatibility between different resins. Furthermore, the laminate produced using this resin composition exhibits suboptimal performance across various properties. Comparative Example 1, which uses the traditional modifier diallyl bisphenol A to modify diallyl bisphenol A, produces prepolymer E, which exhibits good compatibility with other resins and significantly improves glass strength. However, the glass transition temperature, high-temperature modulus, thermal expansion coefficient, and dielectric properties are only marginally improved, still failing to meet the requirements for high-performance packaging substrates.

[0176] The formula of Example 2 is basically the same as that of Comparative Examples 1-2, except that a modified bismaleimide prepolymer formed by prepolymerization of bismaleimide resin and trimerized naphthalene bisallyl ether is used. Compared with Comparative Example 2, the modified bismaleimide prepolymer of Example 2 not only has better compatibility, but also has very significant improvements in peel strength, glass transition temperature, high-temperature modulus, thermal expansion coefficient, and dielectric properties. Compared with Comparative Example 1, the peel strength of Example 2 is slightly reduced, but the glass transition temperature and high-temperature modulus are significantly improved, the thermal expansion coefficient is significantly reduced, and it also has lower dielectric constant and dielectric loss. This shows that using trimerized naphthalene bisallyl ether as a modifier can significantly improve the thermal expansion coefficient, high-temperature modulus, heat resistance, and dielectric properties of the resin composition, so that the laminate has an extremely low thermal expansion coefficient, excellent high-temperature modulus retention, extremely high heat resistance, extremely low dielectric constant, and dielectric loss, making it very suitable for preparing high-performance semiconductor packaging carriers.

[0177] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned 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.

[0178] The above-described embodiments merely represent several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the spirit of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be based on the appended claims, and the description may be used to interpret the content of the claims.

Claims

1. A resin composition, characterized in that The invention comprises the following raw materials in parts by weight: The raw materials of the modified bismaleimide prepolymer include bismaleimide resin and a modifier, and the modifier includes terphenyl naphthalene bisallyl ether.

2. The resin composition according to claim 1, characterized in that In the raw material of the modified bismaleimide prepolymer, the mass ratio of the bismaleimide resin to the terpolymer naphthalene bisallyl ether is 100:(60-100).

3. The resin composition according to claim 2, characterized in that The modifier further comprises one or more of diallyl bisphenol A, diallyl bisphenol S, diallyl bisphenol F and bisphenol A bisallyl ether.

4. The resin composition according to claim 1, characterized in that The bismaleimide resin includes one or more of N,N'-(4,4'-methylenediphenyl)bismaleimide, N,N'-(1,4-phenylene)bismaleimide, N,N'-(4-methyl-1,3-phenylene)bismaleimide, N,N'-m-phenylene bismaleimide, 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 and bismaleimide containing biphenyl structure.

5. The resin composition according to any one of claims 1 to 4, characterized in that The preparation method of the modified bismaleimide prepolymer comprises the following steps: The modifier is heated to melt, and the bismaleimide resin is added to perform a prepolymerization reaction. The modified bismaleimide prepolymer is prepared.

6. The resin composition according to claim 5, characterized in that The preparation method of the modified bismaleimide prepolymer meets one or more of the following conditions: (1) The temperature of the prepolymerization reaction is 140° C. to 170° C.; (2) The prepolymerization reaction time is 60 min to 180 min.

7. The resin composition according to any one of claims 1 to 4, characterized in that The cyanate resin includes one or more of bisphenol A cyanate resin, phenol formaldehyde cyanate resin, bisphenol F cyanate resin, bisphenol M cyanate resin, bisphenol E cyanate resin, naphthalene cyanate resin, biphenyl cyanate resin, bisphenol S cyanate resin and dicyclopentadiene bisphenol cyanate resin.

8. The resin composition according to any one of claims 1 to 4, characterized in that The functional resin includes one or more of benzoxazine resin, modified polyphenylene ether resin and hydrocarbon resin.

9. The resin composition according to claim 8, characterized in that The functional resin meets one or more of the following conditions: (1) The benzoxazine resin includes one or more of bisphenol A type benzoxazine resin, bisphenol F type benzoxazine resin, bisphenol S type benzoxazine resin, main chain type benzoxazine resin, phosphorus-containing benzoxazine resin, dicyclopentadiene benzoxazine resin, biphenyl type benzoxazine resin, tetraphenol ethane benzoxazine resin and naphthalene type benzoxazine resin; (2) The modified polyphenylene ether resin has a structure as shown in the general formula (II): Wherein, m and n are both positive integers, and the sum of m and n is 5 to 60; Y is absent or selected from an alkylene group having 1 to 3 carbon atoms; (3) The hydrocarbon resin includes one or more of polybutadiene and styrene-butadiene copolymer.

10. The resin composition according to any one of claims 1 to 4, characterized in that The inorganic filler includes one or more of zirconium vanadate, zirconium tungstate, hafnium tungstate, microcrystalline glass, eucryptite, silicon dioxide, 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.

11. The resin composition according to any one of claims 1 to 4, characterized in that The resin composition further comprises one or more of a flame retardant, a curing accelerator, a solvent and an auxiliary agent, and the auxiliary agent comprises one or more of a dispersant, a defoamer, a leveling agent, a coupling agent, a surfactant and an ultraviolet absorber.

12. A method for preparing a prepreg, characterized in that: The following steps are involved: The prepreg is prepared by covering the resin composition according to any one of claims 1 to 11 on the surface of a reinforcing material and performing a semi-curing treatment.

13. The method for preparing a prepreg according to claim 12, characterized in that: One or more of the following conditions are met: (1) The method of covering the resin composition on the surface of the reinforcing material includes one or more of an impregnation method, a padding method and a coating method; (2) The reinforcing material comprises one or more of an inorganic fiber material and an organic fiber material; (3) The temperature of the semi-curing treatment is 120°C to 230°C; (4) The semi-curing treatment time is 3 minutes to 15 minutes.

14. A prepreg, characterized in that: The raw materials include reinforcing materials and the resin composition as claimed in any one of claims 1 to 11, or are prepared by the method for preparing the prepreg as claimed in claim 12 or 13.

15. A laminated board, characterized in that: The raw material thereof includes the prepreg as claimed in claim 14.

16. The laminate according to claim 15, characterized in that The laminate is coated with metal foil on one or both sides.

17. The laminate according to claim 16, wherein One or more of the following conditions are met: (1) The metal foil includes copper foil; (2) The thickness of the metal foil is 3 μm to 105 μm.

18. A method for preparing a laminate according to any one of claims 15 to 17, characterized in that: The following steps are involved: The prepreg is subjected to vacuum hot pressing treatment.

19. The method for preparing a laminate according to claim 18, characterized in that: The vacuum hot pressing process satisfies one or more of the following conditions: (1) The temperature of the vacuum hot pressing treatment is 150°C to 300°C; (2) The pressure of the vacuum hot pressing treatment is 10 kgf / cm 2 ~50kgf / cm 2 ; (3) The vacuum degree of the vacuum hot pressing treatment is ≤2 kPa; (4) The vacuum hot pressing treatment time is 200 min to 400 min.

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