WO2025234697A1 - Resin composition, and insulating film and printed circuit board including same - Google Patents

Abstract

A resin composition according to one embodiment of the present invention comprises an epoxy resin, two or more phenolic resins; a thermoplastic resin; and an inorganic filler, wherein the ratio of the epoxy groups in the epoxy resin to the hydroxyl groups in the phenolic resins is 1:0.5 to 1:0.01, the epoxy resin includes a bisphenol-based epoxy resin, a phenol novolac-type epoxy resin, and a bixylenol-type epoxy resin, the phenolic resins include a naphthalene-containing phenolic resin and a triazine-containing phenolic resin, and the weight ratio of the naphthalene-containing phenolic resin to the triazine-containing phenolic resin is 1:2 to 2:1.

Description

Resin composition, insulating film and printed circuit board containing the same

The present application relates to a resin composition, an insulating film comprising the same, and a printed circuit board.

This application claims the benefit of the filing dates of Korean Patent Application No. 10-2024-0059982, filed with the Korean Intellectual Property Office on May 7, 2024, and Korean Patent Application No. 10-2025-0057668, filed with the Korean Intellectual Property Office on April 30, 2025, the contents of which are incorporated herein in their entirety.

As electronic devices become increasingly miniaturized and higher-performance, the buildup layers of multilayer printed circuit boards are becoming more multilayered. In these multilayer printed circuit boards, the coefficients of thermal expansion of the copper wiring and the insulating layer differ significantly. Therefore, reliability tests such as thermal cycling can lead to problems such as cracking in the copper wiring or the insulating layer. Therefore, suppressing the thermal expansion of the resin composition that constitutes the insulating layer has become an urgent task.

One commonly used method for suppressing thermal expansion coefficient is to add inorganic fillers to the resin composition. The greater the amount of inorganic filler added, the more effective it is in lowering the thermal expansion coefficient. However, if the composition contains a large amount of inorganic filler, not only is it difficult to control the viscosity of the coating solution itself, but the inorganic filler is exposed to a greater extent on the surface after roughening, which reduces the peel strength (peeling strength) of the conductive layer formed by plating.

To solve this problem, research is needed on a composition that has excellent peel strength while reducing the thermal expansion coefficient by using an appropriate amount of inorganic filler.

[Prior Art Literature]

(Patent Document 1) Republic of Korea Patent Publication No. 2012-0107277

The present application seeks to provide a resin composition, an insulating film comprising the same, and a printed circuit board.

One embodiment of the present application provides a resin composition comprising an epoxy resin; two or more kinds of phenolic resins; a thermoplastic resin; and an inorganic filler, wherein the ratio of an epoxy group of the epoxy resin to a hydroxyl group of the phenolic resin is 1:0.5 to 1:0.01, the epoxy resin includes a bisphenol-type epoxy resin; a phenol novolac-type epoxy resin; and a bixylenol-type epoxy resin, and the phenolic resin includes a naphthalene-containing phenolic resin and a triazine-containing phenolic resin, and the weight ratio of the naphthalene-containing phenolic resin and the triazine-containing phenolic resin is 1:2 to 2:1.

In addition, another embodiment of the present application provides an insulating film comprising the resin composition or a cured product thereof.

In addition, another embodiment of the present application provides a printed circuit board including the insulating film.

A resin composition according to one embodiment of the present application comprises a naphthalene-containing phenolic resin and a triazine-containing phenolic resin as a curing agent at a specific weight ratio, comprises three specific epoxy resins, and applies the epoxy resin and the phenolic resin such that the composition ratio of the epoxy group of the epoxy resin and the hydroxyl group of the phenolic resin is a specific ratio, thereby appropriately lowering the coefficient of thermal expansion even if an inorganic filler is included in a high content, thereby minimizing reliability problems such as thermal cycles in future multilayer printed circuit boards. In addition, an excellent insulating layer having a peel strength of a conductor layer at an appropriate level or higher can be formed.

Therefore, a multilayer printed circuit board manufactured using a resin composition according to one embodiment of the present application has excellent thermal expansion coefficient properties and has an appropriate surface roughness through desmear treatment, thereby providing excellent copper foil adhesion.

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

In the present application, when it is said that a member is located “on” another member, this includes not only cases where a member is in contact with another member, but also cases where another member exists between the two members.

When a part in this application is said to "include" a certain component, this does not mean that it excludes other components, but rather that it may include other components, unless specifically stated otherwise.

In this application, 'A to B' means a range of A to B.

A method of manufacturing multilayer printed circuit boards by alternately laminating conductor layers and insulating films has been developed, and is currently being used for semiconductor packaging purposes. The manufacturing process of the multilayer printed circuit board first vacuum-laminated a build-up insulating film on the inner layer circuit, and then goes through the steps of precure → drilling → desmear → electroless plating → electroplating → postcure → outer layer circuit formation. Here, the desmear process removes smear with an acid solution and simultaneously forms surface roughness by eroding the surface of the insulating film by a certain amount, which serves to increase adhesion with the copper foil layer formed in the subsequent process.

As a resin composition for the above build-up insulating film, a composition was used in which an inorganic filler was added to an epoxy resin and a phenolic hardener. However, as the amount of inorganic filler added is increased to obtain the desired thermal expansion coefficient, it becomes difficult to control the viscosity of the coating solution, and after the harmonization treatment, the inorganic filler is excessively exposed on the surface, resulting in a decrease in peel strength.

Accordingly, the present application seeks to provide a resin composition having high peel strength while obtaining a desired thermal expansion coefficient by using an appropriate amount of inorganic filler, and a printed circuit board including the same.

A resin composition according to one embodiment of the present application comprises an epoxy resin; two or more kinds of phenolic resins; a thermoplastic resin; and an inorganic filler, wherein a ratio (composition ratio) of an epoxy group of the epoxy resin and a hydroxyl group of the phenolic resin is 1:0.5 to 1:0.01, and the epoxy resin comprises a bisphenol-based epoxy resin; a phenol novolac-type epoxy resin; and a bixylenol-type epoxy resin, and the phenolic resin comprises a naphthalene-containing phenolic resin and a triazine-containing phenolic resin, and the weight ratio of the naphthalene-containing phenolic resin and the triazine-containing phenolic resin is 1:2 to 2:1.

Each component is described below.

epoxy resin

In one embodiment of the present application, the epoxy resin includes a bisphenol-based epoxy resin; a phenol novolac-type epoxy resin; and a bixylenol-type epoxy resin.

In one embodiment of the present application, the bisphenol-based epoxy resin may be a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, or a bisphenol S type epoxy resin.

In one embodiment of the present application, the bisphenol-based epoxy resin may be selected from YD-113, YD-114, YD-114E, YD-114F, YD-115, YD-115G, YD-115CA, KD-1818, YD-127, YD-128, YD-128S, YD-134, YD-136 (Kukdo Chemical), EXA-4850-150, EXA-4850-1000 (DIC), etc., but is not limited thereto.

In one embodiment of the present application, the phenol novolac type epoxy resin may be selected from YDPN-638, YDPN-639, KT-7804 (Kukdo Chemical), etc., but is not limited thereto.

In one embodiment of the present application, the bixylenol-type epoxy resin may be selected from YX-4000H, YX-4000, YX-4000HK, YL-7890 (Mitsubishi Chemical), etc., but is not limited thereto.

In one embodiment of the present application, the resin composition may include four or more types of the epoxy resin.

In one embodiment of the present application, the resin composition may further include an additional epoxy resin other than the bisphenol-based epoxy resin; the phenol novolac-type epoxy resin; and the bixylenol-type epoxy resin.

In one embodiment of the present application, the additional epoxy resin may be any one known in the art without limitation, but it is preferred that two or more epoxy groups exist in one molecule. More specifically, the epoxy resin may be selected from naphthalene-type epoxy resin; anthracene-type epoxy resin; biphenyl-type epoxy resin; tetramethyl biphenyl-type epoxy resin; cresol novolac-type epoxy resin; bisphenol A novolac-type epoxy resin; bisphenol S novolac-type epoxy resin; biphenyl novolac-type epoxy resin; naphthol novolac-type epoxy resin; naphthol phenol cocondensed novolac-type epoxy resin; naphthol coresol cocondensed novolac-type epoxy resin; aromatic hydrocarbon formaldehyde resin-modified phenol resin-type epoxy resin; triphenyl methane-type epoxy resin; tetraphenylethane-type epoxy resin; dicyclopentadiene phenol addition-reaction epoxy resin; phenol aralkyl-type epoxy resin; naphthol aralkyl-type epoxy resin, etc.

In one embodiment of the present application, the total content of the epoxy resin may be 10 to 30 parts by weight based on 100 parts by weight of the total solid content of the resin composition.

In one embodiment of the present application, the total content of the epoxy resin may be 20 to 27 parts by weight based on 100 parts by weight of the total solid content of the resin composition.

When the content of the epoxy resin in the resin composition is within the above range, the formability and processability are improved, and the properties necessary for forming an appropriate roughness during the desmear process can be secured.

In one embodiment of the present application, the content of each of the bisphenol-based epoxy resin; phenol novolac-type epoxy resin; and bixylenol-type epoxy resin is not limited as long as it satisfies the total content range of the epoxy resin and the ratio range of the epoxy group of the epoxy resin and the hydroxyl group of the phenol-based resin.

In one embodiment of the present application, the resin composition may include 10 to 30 parts by weight of the bisphenol-based epoxy resin; 40 to 60 parts by weight of the phenol novolac-type epoxy resin; and 20 to 40 parts by weight of the bixylenol-type epoxy resin, based on 100 parts by weight of the total epoxy resin.

In one embodiment of the present application, the resin composition may include 10 to 30 parts by weight of the bisphenol-based epoxy resin; 20 to 40 parts by weight of the phenol novolac-type epoxy resin; and 40 to 60 parts by weight of the bixylenol-type epoxy resin, based on 100 parts by weight of the total epoxy resin.

phenolic resin

In one embodiment of the present application, the resin composition includes two or more kinds of phenolic resins, the phenolic resins include a naphthalene-containing phenolic resin and a triazine-containing phenolic resin, and the weight ratio of the naphthalene-containing phenolic resin and the triazine-containing phenolic resin is 1:2 to 2:1.

In one embodiment of the present application, the phenolic resin acts as a curing agent in the resin composition and may be referred to as a phenolic curing agent.

The above resin composition provides an effect of preventing a decrease in peel strength due to the use of an inorganic filler by using two types of specific phenolic resins as a hardener within the above weight ratio range.

In one embodiment of the present application, the weight ratio of the naphthalene-containing phenolic resin and the triazine-containing phenolic resin may be 1:1 to 2:1, and preferably 1:1 to 1.8:1.

In one embodiment of the present application, the naphthalene-containing phenolic resin may include a structure represented by the following structural formula 1.

[Structural formula 1]

In the above structural formula 1,

is a connection point with other structures,

X1 and X2 are the same or different from each other, and each independently represents a divalent organic group,

a and b are equal to or different from each other and are each independently an integer from 1 to 6,

n is an integer from 1 to 20.

In one embodiment of the present application, X1 and X2 may be the same as or different from each other, and may each independently be a substituted or unsubstituted alkylene group; a substituted or unsubstituted arylene group; or a substituted or unsubstituted divalent amine group.

In one embodiment of the present application, X1 and X2 may be the same as or different from each other, and may each independently be a substituted or unsubstituted C1 to C30 alkylene group; a substituted or unsubstituted C6 to C30 arylene group; or a substituted or unsubstituted divalent amine group.

In one embodiment of the present application, a and b are the same or different from each other, and are each independently an integer from 1 to 6, preferably an integer from 1 to 4, more preferably 1 or 2, and most preferably 1.

In one embodiment of the present application, when n is an integer greater than or equal to 2, the structures of the repeating units within the parentheses may be the same or different from each other.

In one embodiment of the present application, the terminal group of the naphthalene-containing phenolic resin may be, but is not limited to, hydrogen; a hydroxyl group; an ester group; a cyanate ester group; a substituted or unsubstituted alkyl group; or a substituted or unsubstituted aryl group.

In the present specification, the ester group may refer to an active ester group. The active ester group is an ester functional group that is susceptible to nucleophilic attack, and may be a modified form of the acyl or alkoxy component of a normal ester.

In one embodiment of the present application, the terminal group of the naphthalene-containing phenolic resin may be, but is not limited to, hydrogen; a substituted or unsubstituted C1 to C30 alkyl group; or a substituted or unsubstituted C6 to C30 aryl group.

In one embodiment of the present application, the naphthalene-containing phenolic resin includes, but is not limited to, SN-395, SN-485, SN-395 (Nippon Steel Chemical Co., Ltd.).

In one embodiment of the present application, the triazine-containing phenolic resin may include a structure represented by the following structural formula 2.

[Structural formula 2]

In the above structural formula 2,

is a connection point with other structures,

X3 and X4 are the same or different from each other, and each independently represents a divalent organic group,

R1 is hydrogen; a substituted or unsubstituted alkyl group; a substituted or unsubstituted aryl group; or a substituted or unsubstituted amine group,

c and d are the same or different from each other, and are each independently an integer from 1 to 4,

m is an integer from 1 to 20.

In one embodiment of the present application, R1 may be hydrogen; a substituted or unsubstituted C1 to C30 alkyl group; a substituted or unsubstituted C6 to C30 aryl group; or a substituted or unsubstituted amine group.

In one embodiment of the present application, X3 and X4 may be the same as or different from each other, and may each independently be a substituted or unsubstituted alkylene group; a substituted or unsubstituted arylene group; or a substituted or unsubstituted divalent amine group.

In one embodiment of the present application, X3 and X4 may be the same as or different from each other, and may each independently be a substituted or unsubstituted C1 to C30 alkylene group; a substituted or unsubstituted C6 to C30 arylene group; or a substituted or unsubstituted divalent amine group.

In one embodiment of the present application, c and d are the same or different from each other, and are each independently an integer from 1 to 4, preferably an integer from 1 to 3, more preferably 1 or 2, and most preferably 1.

In one embodiment of the present application, the terminal group of the triazine-containing phenolic resin may be hydrogen; a substituted or unsubstituted alkyl group; or a substituted or unsubstituted aryl group, and preferably may be hydrogen or a methyl group.

In one embodiment of the present application, the terminal group of the triazine-containing phenolic resin may be hydrogen; a substituted or unsubstituted C1 to C30 alkyl group; or a substituted or unsubstituted C6 to C30 aryl group.

In one embodiment of the present application, the triazine-containing phenolic resin includes, but is not limited to, LA-1356, LA-7052, LA-7054, LA-3018-80P, etc.

In one embodiment of the present application, the total content of the phenolic resin may be 5 to 20 parts by weight based on 100 parts by weight of the total solid content of the resin composition.

In one embodiment of the present application, the total content of the phenolic resin may be 5 to 15 parts by weight based on 100 parts by weight of the total solid content of the resin composition.

When the content of the phenolic resin in the resin composition is within the above range, heat resistance and dielectric properties are improved, and properties necessary for forming an appropriate roughness during a desmear process can be secured.

In one embodiment of the present application, the content of each of the naphthalene-containing phenolic resin and the triazine-containing phenolic resin is not limited as long as it satisfies the total content range of the phenolic resin and the ratio range of the epoxy group of the epoxy resin and the hydroxyl group of the phenolic resin.

In one embodiment of the present application, the resin composition may include 50 to 70 parts by weight of the naphthalene-containing phenolic resin and 30 to 50 parts by weight of the triazine-containing phenolic resin based on 100 parts by weight of the total phenolic resin.

In one embodiment of the present application, when the ratio (composition ratio) of the epoxy group of the epoxy resin and the hydroxyl group of the phenolic resin is 1:0.5 to 1:0.01, the composition has excellent thermal expansion coefficient properties and has appropriate surface roughness through desmear treatment, thereby providing excellent peel strength.

When the number of hydroxyl groups of the phenolic resin exceeds 0.5 per epoxy group of the epoxy resin, it may have an excellent thermal expansion coefficient, but it may not be able to improve the peel strength, which may cause problems with blistering and reliability on the substrate.

In one embodiment of the present application, the ratio of the epoxy group of the epoxy resin and the hydroxyl group of the phenolic resin may be 1:0.5 to 1:0.1, 1:0.5 to 1:0.2, or 1:0.5 to 1:0.3.

Weapon refills

In this specification, the inorganic filler is meant to be used to control desired physical properties, such as hygroscopicity suppression, high storage modulus, low coefficient of thermal expansion (CTE), viscosity, and improved curability exhibited by the curable resin composition.

In one embodiment of the present application, the average particle diameter of the inorganic filler may be 0.01 ㎛ or more and 5 ㎛ or less.

In one embodiment of the present application, the inorganic filler may be surface-treated with a surface treatment agent such as a coupling agent.

In one embodiment of the present application, the inorganic filler may be silica, silicate, barium sulfate, alumina, etc., but is not limited thereto.

In this specification, the silica may include, but is not limited to, spherical silica, fused silica, hollow silica, crystalline silica, amorphous silica, etc., and commercially available silica such as SOC1 and SOC2 (Admatex) may be used.

In one embodiment of the present application, the inorganic filler may include silica particles.

In one embodiment of the present application, the inorganic filler may include only silica particles and may not include any other inorganic filler other than the silica particles.

The average particle diameter of the above silica particles may be 0.3 ㎛ or less, 0.2 ㎛ or less, or 0.05 ㎛ or more.

In one embodiment of the present application, the content of the inorganic filler may be 60 to 75 parts by weight based on 100 parts by weight of the total solid content of the resin composition.

In one embodiment of the present application, the content of the inorganic filler may be 60 to 70 parts by weight based on 100 parts by weight of the total solid content of the resin composition.

A higher content of inorganic filler in a resin composition reduces the thermal expansion coefficient of the resin composition, thereby preventing cracking between the copper wiring and the insulating layer. However, if the resin composition contains excessive amounts of inorganic filler, viscosity control becomes difficult, and the exposed portion of the inorganic filler on the surface after the blending process increases, resulting in reduced peel strength.

When the above-mentioned inorganic filler is included in the resin composition within the above content range, the resin composition can have a low thermal expansion coefficient due to the inorganic filler, while having an appropriate surface roughness due to the composition of the epoxy resin and phenolic resin, and can provide excellent peel strength.

When the above-mentioned inorganic filler is included in an amount exceeding 75 parts by weight, the thermal expansion coefficient can be further reduced, but an appropriate peel strength cannot be obtained, and when the above-mentioned inorganic filler is included in an amount less than 60 parts by weight, the thermal expansion coefficient is high, which causes a problem in reliability in a thermal cycle test.

thermoplastic resin

In one embodiment of the present application, the resin composition may further include a thermoplastic resin to improve the mechanical strength, film moldability, etc. of the cured product. The thermoplastic resin is not particularly limited as long as it is widely known in the art, and may include, for example, one or more selected from phenoxy resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, polycarbonate resin, polyetheretherketone resin, polyester resin, and polyvinyl acetal resin. It is more preferable that the thermoplastic resin include a polyvinyl acetal resin.

In one embodiment of the present application, the thermoplastic resin may be a polyvinyl acetal resin.

In one embodiment of the present application, the total content of the thermoplastic resin may be 0.1 to 5 parts by weight based on 100 parts by weight of the total solid content of the resin composition.

Curing accelerator

In one embodiment of the present application, the resin composition may additionally include a curing accelerator.

By including the above curing accelerator, the epoxy resin, phenolic resin, etc. in the resin composition can be cured efficiently, thereby shortening the curing time.

In one embodiment of the present application, the curing accelerator is not particularly limited as long as it is known in the art, but may include at least one selected from a phosphorus-based curing accelerator, an amine-based curing accelerator, and an imidazole-based curing accelerator.

Examples of the above-mentioned curing accelerator include, but are not limited to, triphenyl phosphine.

Examples of the above amine-based curing accelerators include, but are not limited to, triethylamine, tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene.

The above imidazole-based curing accelerators are 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-Cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazineisocyanuric acid adduct, 2-phenylimidazoleisocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, Examples include, but are not limited to, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline.

In one embodiment of the present application, the content of the curing accelerator may be 0.01 to 0.5 parts by weight based on 100 parts by weight of the total solid content of the resin composition.

menstruum

In one embodiment of the present application, the resin composition may additionally include a solvent.

In one embodiment of the present application, the solvent may be applied without special limitation as long as it is known in the technical field to which the present invention pertains to enable the formation of a resin composition. As a non-limiting example, the solvent may be one or more compounds selected from the group consisting of esters, ethers, ketones, aromatic hydrocarbons, and sulfoxides.

The above ester solvents are ethyl acetate, n-butyl acetate, isobutyl acetate, amyl formate, isoamyl acetate, isobutyl acetate, butyl propionate, isopropyl butyrate, ethyl butyrate, butyl butyrate, methyl lactate, ethyl lactate, gamma-butyrolactone, epsilon-caprolactone, delta-valerolactone, alkyl oxyacetic acids (e.g., methyl oxyacetic acid, ethyl oxyacetic acid, butyl oxyacetic acid (e.g., methyl methoxyacetic acid, ethyl methoxyacetic acid, butyl methoxyacetic acid, methyl ethoxyacetic acid, ethyl ethoxyacetic acid, etc.)), alkyl 3-oxypropionic acid esters (e.g., methyl 3-oxypropionate, ethyl 3-oxypropionate, etc. (e.g., 3-methoxypropionate methyl, 3-methoxypropionate ethyl, 3-ethoxypropionate methyl, 3-ethoxypropionate ethyl, etc.), 2-oxypropionic acid alkyl esters (e.g., methyl 2-oxypropionate, ethyl 2-oxypropionate, propyl 2-oxypropionate, etc. (e.g., methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate)), 2-oxy-2-methylpropionate methyl and 2-oxy-2-methylpropionate ethyl (e.g., methyl 2-methoxy-2-methylpropionate, ethyl 2-ethoxy-2-methylpropionate, etc.), methyl pyruvate, It can be ethyl pyruvate, propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl 2-oxobutanoate, ethyl 2-oxobutanoate, etc.

The above ether solvent may be diethylene glycol dimethyl ether, tetrahydrofuran, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, etc.

The above ketone solvent may be methyl ethyl ketone (MEK), cyclohexanone, cyclopentanone, 2-heptanone, 3-heptanone, N-methyl-2-pyrrolidone, etc.

The above aromatic hydrocarbon solvent may be toluene, xylene, anisole, limonene, etc.

The above sulfoxide solvent may be dimethyl sulfoxide, etc.

In one embodiment of the present application, the resin composition may include the solvent such that the solids concentration of the resin composition is 60% to 80%. When the solids concentration of the resin composition satisfies the above range, it has an appropriate viscosity, facilitates coating, and can form a uniform insulating layer.

Other additives

In one embodiment of the present application, the resin composition may further include additives known in the art. The additives may include, but are not limited to, one or more selected from a leveling agent, a wetting agent, and an antistatic agent.

In one embodiment of the present application, the leveling agent controls the flowability of the resin composition when used in the future, so that when applied to a surface in the future, defects such as craters are eliminated. Examples of the leveling agent known in the art include, but are not particularly limited to, BYK 350, BYK 354, BYK 356, BYK 359, and BYK 399. In some cases, one type or two or more types of the leveling agent may be used in combination, and the content thereof may be appropriately changed as long as it does not deviate from the scope of the present invention.

In one embodiment of the present application, the wetting agent is a substance known in the art that accelerates wetting and aids in the coagulation of the inorganic filler. The wetting agent is not particularly limited to a specific substance. If necessary, one type of wetting agent may be used alone or in combination of two or more types, and the content may be appropriately varied without departing from the scope of the present invention.

In one embodiment of the present application, the antistatic agent is a substance known in the art that provides an antistatic effect, and is not particularly limited. Depending on the need, one type of antistatic agent may be used alone or in combination of two or more types, and the content may be appropriately varied without departing from the scope of the present invention.

In one embodiment of the present application, the resin composition may be applied to a printed circuit board. More specifically, the resin composition may be applied as an insulating film for a printed circuit board. The insulating film may be used as an interlayer insulating material for a multilayer printed circuit board.

insulating film

In addition, another embodiment of the present application provides an insulating film comprising the resin composition or a cured product thereof.

In one embodiment of the present application, the cured product can be obtained by thermal curing.

In one embodiment of the present application, the thermal curing may be performed by conditions and a heating device known in the art, and may be performed by curing and drying for a certain period of time under conditions of 100°C or higher, for example.

The thickness of the insulating film according to one embodiment of the present application may be 5 ㎛ or more, 10 ㎛ or more, or 15 ㎛ or more, and 50 ㎛ or less, 40 ㎛ or less, or 35 ㎛ or less.

The coefficient of thermal expansion of the insulating film according to one embodiment of the present application may be 25 ppm/℃ or less.

In one embodiment of the present application, the lower limit of the thermal expansion coefficient value of the insulating film is not limited, but may be, for example, 0 ppm/℃ or more.

The above thermal expansion coefficient is a value measured using a thermo mechanical analyzer (TMA) in the range of 25°C to 120°C after heat-curing the insulating film at 190°C for 90 minutes.

Insulating films that fall within the above-mentioned range of thermal expansion coefficients will not experience deformation such as peeling or cracking, as there will be little difference in expansion rate with the support in the future.

Conversely, if the coefficient of thermal expansion exceeds 25 ppm/℃, reliability problems may arise in summer cycle tests.

The peel strength of the insulating film according to one embodiment of the present application may be 0.4 kgf/cm or more.

In one embodiment of the present application, the insulating film may have a peel strength of 0.4 kgf/cm or more when measured according to the ASTM D6862 method.

If the peel strength of the above insulating film is less than 0.4 kgf/cm, problems with blistering and reliability occur on the substrate.

The above peel strength is obtained by measuring the 90-degree peel strength of the copper plating layer using a Stable Micro Systems Texture Analyzer (TA-XT Plus) after copper plating the insulating film as described below.

1) Primary copper plating treatment (electroless chemical copper plating)

After processing to a plating thickness of 0.5㎛ to 1.0㎛ using Atotech's Printoganth MV product, dry in a hot air oven at 150℃ for 30 minutes.

2) Secondary copper plating treatment (electroplating)

After processing to a plating thickness of approximately 20㎛ using Atotech Expt Inpro SAP6, heat treatment is performed in a hot air oven at 190℃ for 1 hour.

The surface roughness (Ra) of the insulating film according to one embodiment of the present application may be 200 nm or more and 400 nm or less, or 300 nm or more and 400 nm or less.

The above surface roughness is obtained by laminating the insulating film on a CCL (copper clad laminate) substrate using a vacuum pressurized laminator at a temperature of 100°C and a pressure of 0.7 MPa for 30 seconds, followed by pre-cure in a hot air oven at 100°C for 30 minutes and then at 170°C for 30 minutes, and then peeling off the supporting film (PET film) of the insulator to expose the insulating layer, followed by desmear treatment. Specifically, the desmear treatment is performed in three steps: swelling solution treatment (60°C, 5 minutes) - oxidation solution treatment (80°C, 20 minutes) - neutralizing solution treatment (50°C, 4 minutes) using Atotech's Securiganth MV series treatment solution. The surface of the insulating layer treated with desmear is measured 5 times per sample using an Optical Profiler (Nanoview 3D surface profiler NV-2700, Nanosystem) (WSI mode, 20x lens), and the surface roughness (Ra) is calculated as the average value.

Since the above insulating film uses the above-described resin composition as is or a cured product thereof, the contents regarding the resin composition can be applied.

printed circuit board

In addition, another embodiment of the present application provides a printed circuit board including the insulating film.

The above printed circuit board may be a multilayer printed circuit board, and the number of layers included in the multilayer printed circuit board is not limited. For example, depending on the purpose of use, use, etc. of the multilayer printed circuit board, the multilayer printed circuit board may include a structure of 2 to 20 layers.

Hereinafter, examples will be provided to specifically explain the present application. However, the embodiments according to the present application may be modified in various ways, and the scope of the present application is not construed as being limited to the embodiments described below. The embodiments of the present application are provided to more fully explain the present application to those of average skill in the art.

<Manufacturing Example 1> Manufacturing of insulating film of Example 1

As epoxy resin, 22 parts by weight of bisphenol-based epoxy resin (YD-128, Kukdo Chemical), 66 parts by weight of phenol novolac-type epoxy resin (YDPN-639, Kukdo Chemical), 33 parts by weight of bixylenol-type epoxy resin (YX-4000H), 31 parts by weight of naphthalene-containing phenol-based resin (SN-485), 22 parts by weight of triazine-containing phenol-based resin (LA-1356, DIC), 315 parts by weight of silica slurry (SOC2) having an average particle size of 0.1㎛, and 10 parts by weight of polyvinyl acetal resin (KS-1) were mixed in MEK (methyl ethyl ketone) solvent to a total solid concentration of 70%, and stirred with a mechanical stirrer at 250 rpm for 3 hours, and 2.5 parts by weight of a curing accelerator (DMAP) was mixed using a paste mixer to prepare a coating solution. It was manufactured.

The manufactured coating solution was coated on a 38 ㎛ thick PET film using an applicator, and then dried at 100 ℃ for 8 minutes to manufacture an insulating film (Example 1) having a thickness of 30 ㎛.

In the above Example 1, the composition ratio of the epoxy group of the epoxy resin and the hydroxyl group of the phenolic resin is 1:0.48, and the weight ratio of the naphthalene-containing phenolic resin and the triazine-containing phenolic resin is 1.4:1.

<Manufacturing Examples 2, 3 and Comparative Manufacturing Examples 1 to 6> Manufacturing of insulating films of Examples 2, 3 and Comparative Examples 1 to 6

An insulating film was manufactured using the same method as Manufacturing Example 1, except that the composition and content (parts by weight) described in Table 1 below were changed.

division type Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 epoxy
Suzy (A) YD-128 22 25 25 18 17 20 18 40 25 YX-4000H 33 38 37 28 26 30 28 60 38 YDPN-639 66 64 62 55 52 60 55 - 64 phenol
Hardener (B) LA-1356 22 20 21 30 - 65 30 20 20 SN-485 31 27 30 43 80 - - 30 27 GPH-63 - - - - - - 43 - - Composition ratio of epoxy group (epoxy resin) and hydroxyl group (phenolic resin) 1:0.48 1:0.4 1:0.45 1:0.8 1:0.8 1:0.8 1:0.8 1:0.48 1:0.4 weapon
Filler (C) SOC2 315 315 315 315 315 315 315 315 315 thermoplastic resin (D) KS-1 10 10 10 10 10 10 10 10 - hardening accelerator DMAP 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5

*GPH-63: Biphenyl aralkyl-containing phenolic resin

*The above weight is based on solid content

Experimental Example 1

The properties of the insulating films of Examples 1 to 3 and Comparative Examples 1 to 6 were evaluated and shown in Table 2 below. The evaluation method for the properties described in Table 2 below is as follows.

Coefficient of thermal expansion (CTE (coefficient of thermal expansion), ppm/℃)

The insulating film was cut into samples with a width of 4.8 mm, a length of 16 mm, and a thickness of 30 ㎛, and after heat curing at 190°C for 90 minutes, the thermal expansion coefficient was measured in the range of 25°C to 120°C using a thermo mechanical analyzer (TMA).

Surface roughness (Ra, nm)

1) Desmear treatment

The insulating film was laminated on a CCL (copper clad laminate) substrate by pressing it for 30 seconds using a vacuum pressurized laminator at a temperature of 100°C and a pressure of 0.7 MPa, and then pre-cured in a hot air oven at 100°C for 30 minutes and then at 170°C for 30 minutes.

Afterwards, the supporting film (PET film) of the insulator was peeled off to expose the insulating layer, and then desmear treatment was performed. The desmear treatment was performed in three steps: swelling solution treatment (60°C, 5 minutes) - oxidation solution treatment (80°C, 20 minutes) - neutralizing solution treatment (50°C, 4 minutes) using Atotech's Securiganth MV series treatment solution.

2) Surface roughness (Ra, nm) measurement

The surface of the desmear-treated insulating layer was measured five times per sample using an Optical Profiler (Nanoview 3D surface profiler NV-2700, Nanosystem) (WSI mode, 20x lens), and the surface roughness (Ra) was calculated as the average value.

Phil Kang-do

1) Copper plating treatment

Copper plating was performed in two stages: electroless chemical copper plating and electrolytic copper plating. Electroless chemical copper plating was performed using Atotech's Printoganth MV product to a plating thickness of 0.5 to 1.0 μm, and after treatment, it was dried in a hot air oven at 150°C for 30 minutes.

Electroplating was performed using Atotech's Expt Inpro SAP6 chemical to a plating thickness of approximately 20 ㎛, and after treatment, heat treatment was performed in a hot air oven at 190 ℃ for 1 hour.

2) Measurement of peel strength (kgf/cm)

The 90-degree peel strength of the copper plating layer was measured using a Stable Micro Systems Texture Analyzer (TA-XT Plus).

Coefficient of thermal expansion
(CTE, ppm/℃) Surface roughness
(Ra, nm) Phil Kang-do
(kgf/cm) Example 1 25 300 0.4 Example 2 25 380 0.4 Example 3 24 350 0.4 Comparative Example 1 24 120 0.15 Comparative Example 2 Sampling not possible 400 Blister Comparative Example 3 27 500 0.3 Comparative Example 4 29 300 0.2 Comparative Example 5 27 500 0.3 Comparative Example 6 26 400 0.2

Looking at the results in Table 2 above, it was confirmed that the insulating films of Examples 1 to 3 exhibited excellent properties as insulating films by satisfying a thermal expansion coefficient of 25 ppm/℃ or less, having a high peel strength of 0.4 kgf/cm or more, and implementing an appropriate surface roughness value of 200 nm or more and 400 nm or less.

On the other hand, Comparative Example 1 does not satisfy the range of the present invention in the ratio (composition ratio) of the epoxy group of the epoxy resin and the hydroxyl group of the phenolic resin, so although the thermal expansion coefficient is appropriate, the surface roughness is low and the peel strength has a value of less than 0.4 kgf/cm, so that a short circuit occurs in a future reliability test, and therefore it can be seen that it is unsuitable as an insulating film.

In addition, Comparative Examples 2 and 3 used only one type of phenolic resin, and Comparative Example 4 used two types of phenolic resins, but used a biphenyl aralkyl-containing phenolic resin and a triazine-containing phenolic resin, that is, did not use a naphthalene-containing phenolic resin. In the case of Comparative Example 2, it can be seen that it is unsuitable for use as an insulating film due to the occurrence of blisters, and Comparative Examples 3 and 4 have a coefficient of thermal expansion exceeding 25 ppm/℃, making it difficult to secure minimal warpage and may cause low yield problems, and the peel strength does not reach 0.4 kgf/cm, causing short circuits in future reliability tests, so it can be seen that it is highly unsuitable for use as an insulating film.

Finally, Comparative Example 5 used two types of epoxy resin instead of three, and the use of a phenol novolac-type epoxy resin was omitted. Therefore, although the composition of the phenol hardener and the composition ratio of the epoxy group and the hydroxyl group satisfied the present invention, it was confirmed that the peel strength was less than 0.4 kgf/cm, making it unsuitable for use as an insulating film. Comparative Example 6 did not include a thermoplastic resin, and it was confirmed that the peel strength was less than 0.4 kgf/cm, making it unsuitable for use as an insulating film.

Claims (9)

epoxy resin; Two or more types of phenolic resins; thermoplastic resin; and A resin composition comprising an inorganic filler, The ratio of the epoxy group of the above epoxy resin and the hydroxyl group of the above phenolic resin is 1:0.5 to 1:0.01, The above epoxy resin includes bisphenol-based epoxy resin; phenol novolac-type epoxy resin; and bixylenol-type epoxy resin. The above phenolic resin includes a naphthalene-containing phenolic resin and a triazine-containing phenolic resin, A resin composition wherein the weight ratio of the naphthalene-containing phenolic resin and the triazine-containing phenolic resin is 1:2 to 2:1. A resin composition according to claim 1, wherein the content of the inorganic filler is 60 to 75 parts by weight based on 100 parts by weight of the total solid content of the resin composition. A resin composition according to claim 1, wherein the thermoplastic resin is a polyvinyl acetal resin. A resin composition according to claim 1, wherein the total content of the epoxy resin is 10 to 30 parts by weight based on 100 parts by weight of the total solid content of the resin composition. A resin composition according to claim 1, wherein the total content of the phenolic resin is 5 to 20 parts by weight based on 100 parts by weight of the total solid content of the resin composition. A resin composition according to claim 1, wherein the total content of the thermoplastic resin is 0.1 to 5 parts by weight based on 100 parts by weight of the total solid content of the resin composition. A resin composition according to claim 1, wherein the resin composition further comprises a curing accelerator. An insulating film comprising a resin composition or a cured product thereof according to any one of claims 1 to 7. A printed circuit board comprising the insulating film of claim 8.