Polyacetal resin composition excellent in heat stability and surface processability and process for surface treating same

Claim 2

A surface-treated polyacetal resin product having no surface cracks noticeable to the naked eye and having surface characteristics such that when chemical nickel is deposited thereon by immersing the product in an aqueous chemical nickel solution at 40° C. for 10 minutes to deposit chemical nickel on the surface thereof, eluting the deposited chemical nickel from said surface, and determining the amount of chemical nickel eluted, the nickel weight obtained by dividing the area of the surface deposited with nickel to give the amount of chemical nickel deposited is 85-150 mg/dm 2 and wherein the peeling strength of a plated metal layer plated by chemically plating a nickel layer by means of a chemical nickel solution, then electroplating with copper so as to give a mean plating thickness of about 40μ, drawing at least two parallel breaking lines or nicks on the plated metal surface at a distance of 10 mm apart, pulling or stretching the plated metal layer between said lines or nicks in a direction perpendicular to said surface and measuring the stress necessary for peeling is 1.0 kg/cm or more; said surface-treated polyacetal resin product being obtained by a process comprising (1) blending (a) about 100 parts by weight of polyacetal resin, (b) about 2 to about 35 parts by weight of a carbonate, phosphate or acetate of a metal belonging to Group II of the Periodic Table or a mixture thereof and (c) about 0.01 to about 20 parts by weight of a polymer, a copolymer or a mixture thereof of a compound selected from the group consisting of unsaturated polyesters, alkyl esters of acrylic acid or methacrylic acid, amides of acrylic acid or methacrylic acid, triallyl cyanurate, diallyl phthalate, vinyl acetate and divinylbenzene; (2) molding the resulting polyacetal resin composition into the desired configuration; and (3) conditioning the resulting molded product by dipping said molded product in an aqueous solution consisting essentially of sulfuric acid.

Claim 3

A surface-treated polyacetal resin product according to claim 1, wherein said compound of component (c) is an unsaturated polyester.

Claim 4

A surface-treated polyacetal resin product according to claim 1, wherein said compound of component (c) is a member selected from the group consisting of a polymer of methylacrylate, a polymer of ethylacrylate, a polymer of methylmethacrylate, a polymer of ethylmethacrylate, a polymer of acrylamide, a polymer of methacrylamide, a polymer of triallylcyanurate, a polymer of diallylphthalate, a polymer of vinylacetate, a polymer of divinylbenzene and a polymer of polyvinylacetate.

Claim 5

A surface-treated polyactal resin product according to claim 1, wherein said component (c) is a polymer, copolymer or a mixture thereof of an unsaturated polyester and acrylamide.

Claim 6

A surface-treated polyacetal resin product according to claim 1, wherein said product further comprises a surface coating layer chemically plated and subsequently electroplated or coated thereon.

Claim 7

A surface-treated polyacetal resin product according to claim 5, wherein said coating layer is metal.

Claim 8

A surface-treated polyacetal resin product according to claim 5, wherein said coating layer is nickel or copper.

Claim 9

A surface-treated polyacetal resin product according to claim 5, wherein said coating layer is Pd and Ni.

Claim 10

A surface-treated polyacetal resin product according to claim 5, wherein said coating layer is Cu/Ni/Cr.

Claim 11

A surface-treated polyacetal resin product according to claim 5, wherein said coating layer is acrylic.

Claim 12

A surface-treated polyacetal resin product according to claim 5, wherein said coating layer is an adhesive.

Claim 13

A surface-treated polyacetal resin product having no surface cracks noticeable to the naked eye and having surface characteristics such that when chemical nickel is deposited thereon by immersing the product in an aqueous chemical nickel solution at 40° C. for 10 minutes to deposit chemical nickel on the surface thereof, eluting the deposited chemical nickel from said surface, and determining the amount of chemical nickel eluted, the nickel weight obtained by dividing the area of the surface deposited with nickel to give the amount of chemical nickel deposited is 85-150 mg/dm 2 and wherein the peeling strength of a plated metal layer plated by chemically plating a nickel layer by means of a chemical nickel solution, then electroplating with copper so as to give a mean plating thickness of about 40μ, drawing at least two parallel breaking lines or nicks in a direction perpendicular to said surface and measuring the stress necessary for peeling is 1.0 kg/cm or more; said surface-treated polyacetal resin product being obtained by a process comprising (1) blending (a) about 100 parts by weight of polyacetal resin, (b) about 2 to about 35 parts by weight of a carbonate, phosphate or acetate of a metal belonging to Group II of the Periodic Table or a mixture thereof and (c) about 0.01 to about 20 parts by weight of a polymer, a copolymer or a mixture thereof of a compound selected from the group consisting of unsaturated polyesters, alkyl esters of acrylic acid or methacrylic acid, amides of acrylic acid or methacrylic acid, triallyl cyanurate, diallyl phthalate, vinyl acetate and divinylbenzene; (2) molding the resulting polyacetal resin composition into the desired configuration; and (3) conditioning the resulting molded product by dipping said molded product in an aqueous solution containing sulfuric acid but not more than about 4% by weight of potassium bichromate.

Claim 14

A surface-treated polyacetal resin product having no surface cracks noticeable to the naked eye and having surface characteristics such that when chemical nickel is deposited thereon by immersing the product in an aqueous chemical nickel solution at 40° C. for 10 minutes to deposit chemical nickel on the surface thereof, eluting the deposited chemical nickel from said surface, and determining the amount of chemical nickel eluted, the nickel weight obtained by dividing the area of the surface deposited with nickel to give the amount of chemical nickel deposited is 85-150 mg/dm 2 and wherein the peeling strength of a plated metal layer plated by chemically plating a nickel layer by means of a chemical nickel solution, then electroplating with copper so as to give a mean plating thickness of about 40μ, drawing at least two parallel breaking lines or nicks in a direction perpendicular to said surface and measuring the stress necessary for peeling is 1.0 kg/cm or more; said surface-treated polyacetal resin product being obtained by a process comprising (1) blending (a) about 100 parts by weight of polyacetal resin, (b) about 2 to about 35 parts by weight of a carbonate, phosphate or acetate of a metal belonging to Group II of the Periodic Table or a mixture thereof and (c) about 0.01 to about 20 parts by weight of a polymer, a copolymer or a mixture thereof of a compound selected from the group consisting of unsaturated polyesters, alkyl esters of acrylic acid or methacrylic acid, amides of acrylic acid or methacrylic acid, triallyl cyanurate, diallyl phthalate, vinyl acetate and divinylbenzene; (2) molding the resulting polyacetal resin composition into the desired configuration; and (3) conditioning the resulting molded product by dipping said molded product in an aqueous solution containing sulfuric acid but not more than about 4% by weight of potassium bichromate.

Claim 15

A surface-treated polyacetal resin product according to claim 12, wherein said aqueous solution containing sulfuric acid has a sulfuric acid concentration of 35% by weight to 75% by weight.

Claim 16

A surface-treated polyacetal resin product according to claim 12, wherein said aqueous solution containing sulfuric acid additionally contains phosphoric acid.

Claim 17

A surface-treated polyacetal resin product according to claim 14, wherein the composition of sulfuric acid, phosphoric acid and water is represented by the formulas x≧15 and y≧45-(9/7)x or y≦90-(6/5)x wherein x represents the weight amount of 96% sulfuric acid and y represents the weight percent amount of 85% phosphoric acid.

Claim 18

A surface-treated polyacetal resin product according to claim 12, wherein said aqueous solution containing sulfuric acid additionally contains potassium bichromate.

Claim 19

A surface-treated polyacetal resin product according to claim 14, wherein the roughening step of surface treatment is carried out with a solution having a composition of sulfuric acid/phosphoric acid/water of about 40/about 25/about 35, respectively, as expressed by parts by weight.

Claim 20

A surface-treated polyacetal resin product according to claim 14, which is further chemically plated and then electroplated on the treated surface.

Claim 21

A surface-treated polyacetal resin product according to claim 16, wherein the roughening step of surface treatment is carried out with a solution comprising 55 parts by weight of 96% sulfuric acid, 4 parts by weight of potassium bichromate, and 45 parts by weight of water.

Claim 22

A surface-treated polyacetal resin product having no surface cracks noticeable to the naked eye and having surface characteristics such that when chemical nickel is deposited thereon by immersing the product in an aqueous chemical nickel solution at 40° C. for 10 minutes to deposit chemical nickel on the surface thereof, eluting the deposited chemical nickel from said surface, and determining the amount of chemical nickel eluted, the nickel weight obtained by dividing the area of the surface deposited with nickel to give the amount of chemical nickel deposited is 85-150 mg/dm 2 and wherein the peeling strength of a plated metal layer plated by chemically plating a nickel layer by means of a chemical nickel solution, then electroplating with copper so as to give a mean plating thickness of about 40μ, drawing at least two parallel breaking lines or nicks on the plated metal surface at a distance of 10 mm apart, pulling or stretching the plated metal layer between said lines or nicks in a direction perpendicular to said surface and measuring the stress necessary for peeling is 1.0 kg/cm or more; said surface-treated polyacetal resin product being obtained by a process comprising (1) blending (a) about 100 parts by weight of polyacetal resin, (b) about 2 to about 35 parts by weight of a carbonate, phosphate or acetate of a metal belonging to Group II of the Periodic Table or a mixture thereof and (c) about 0.01 to about 20 parts by weight of a polymer, a copolymer or a mixture thereof of a compound selected from the group consisting of unsaturated polyesters, alkyl esters of acrylic acid or methacrylic acid, amides of acrylic acid or methacrylic acid, triallyl cyanurate, diallyl phthalate, vinyl acetate and divinylbenzene; (2) molding the resulting polyacetal resin composition into the desired configuration; and (3) conditioning the resulting molded product by dipping said molded product in an aqueous solution consisting essentially of sulfuric acid and phosphoric acid.

Claim 23

A surface-treated polyacetal resin product having no surface cracks noticeable to the naked eye and having surface characteristics such that when chemical nickel is deposited thereon by immersing the product in an aqueous chemical nickel solution at 40° C. for 10 minutes to deposit chemical nickel on the surface thereof, eluting the deposited chemical nickel from said surface, and determining the amount of chemical nickel eluted, the nickel weight obtained by dividing the area of the surface deposited with nickel to give the amount of chemical nickel deposited is 85-150 mg/dm 2 and wherein the peeling strength of a plated metal layer plated by chemically plating a nickel layer by means of a chemical nickel solution, then electroplating with copper so as to give a mean plating thickness of about 40μ, drawing at least two parallel breaking lines or nicks on the plated metal surface at a distance of 10 mm apart, pulling or stretching the plated metal layer between said lines or nicks in a direction perpendicular to said surface and measuring the stress necessary for peeling is 1.0 kg/cm or more; said surface-treated polyacetal resin product being obtained by a process comprising (1) blending (a) about 100 parts by weight of polyacetal resin, (b) about 2 to about 35 parts by weight of a carbonate, phosphate or acetate of a metal belonging to Group II of the Periodic Table or a mixture thereof and (c) about 0.01 to about 20 parts by weight of a polymer, a copolymer or a mixture thereof of a compound selected from the group consisting of unsaturated polyesters, alkyl esters of acrylic acid or methacrylic acid, amides of acrylic acid or methacrylic acid, triallyl cyanurate, diallyl phthalate, vinyl acetate and divinylbenzene; (2) molding the resulting polyacetal resin composition into the desired configuration; and (3) conditioning the resulting molded product by dipping said molded product in an aqueous solution consisting essentially of sulfuric acid and phosphoric acid.

Claim 24

A surface-treated polyacetal resin product according to claim 20, wherein said aqueous solution consisting essentially of sulfuric acid and phosphoric acid has a sulfuric acid concentration of 35% by weight to 75% by weight.

Claim 25

A surface-treated polyacetal resin product according to claim 20, wherein the composition of sulfuric acid, phosphoric acid and water is represented by the formulas x≧15 and y≧45-(9/7)x or y≦90-(6/5)x wherein x represents the weight amount of 96% sulfuric acid and y represents the weight percent amount of 85% phosphoric acid.

Claim 26

A surface-treated polyacetal resin product according to claim 20, wherein the roughening step of surface treatment is carried out with a solution having a composition of sulfuric acid/phosphoric acid/water of about 40/about 25/about 35, respectively, as expressed by parts by weight.

Claim 27

A surface-treated polyacetal resin product according to claim 20, which is further chemically plated and then electroplated on the treated surface.

Claim 28

A surface-treated polyacetal resin product according to claim 20, wherein said compound of component (c) is an unsaturated polyester.

Claim 29

A surface-treated polyacetal resin product according to claim 1, wherein said compound of component (c) is a member selected from the group consisting of a polymer of methylacrylate, a polymer of ethylacrylate, a polymer of methylmethacrylate, a polymer of ethylmethacrylate, a polymer of acrylamide, a polymer of methacrylamide, a polymer of triallylcyanurate, a polymer of diallylphthalate, a polymer of vinylacetate, a polymer of divinylbenzene and a polymer of polyvinylacetate.

Claim 30

A surface-treated polyacetal resin product according to claim 20, wherein said component (c) is a polymer, copolymer or a mixture thereof of an unsaturated polyester and acrylamide.

Claim 31

A surface-treated polyacetal resin product according to claim 20, wherein said product further comprises a surface coating layer chemically plated and subsequently electroplated or coated thereon.

Claim 32

A surface-treated polyacetal resin product according to claim 28, wherein said coating layer is metal.

Claim 33

A surface-treated polyacetal resin product according to claim 28, wherein said coating layer is nickel or copper.

Claim 34

A surface-treated polyacetal resin product according to claim 28, wherein said coating layer is Pb and Ni.

Claim 35

A surface-treated polyacetal resin product according to claim 28, wherein said coating layer is Cu/Ni/Cr.

Claim 36

A surface-treated polyacetal resin product according to claim 28, wherein said coating layer is acrylic.

Claim 37

A surface-treated polyacetal resin product according to claim 28, wherein said coating layer is an adhesive.