The invention relates to fluoropolymer filament for use in 3-D printing, and 3-D printed fluoropolymer articles having low warpage, excellent chemical resistance, excellent water resistance, flame resistance, and good mechanical integrity. Additionally, the articles of the invention have good shelf life without the need for special packaging. In particular, the invention relates to filament, 3-D printed polyvinylidene fluoride (PVDF) articles, and in particular material extrusion 3-D printing. The articles may be formed from PVDF homopolymers, copolymers, such as KYNAR resins from Arkema, as well as polymer blends with appropriately defined low shear melt viscosity. The PVDF may optionally be a filled PVDF formulation. The physical properties of the 3-D printed articles can be maximized and warpage minimized by optimizing processing parameters.

A member contains a fluorine-containing polymer and a fluorine-containing surfactant, in which provided that a mass-based content of the fluorine-containing surfactant in at least a surface of a portion of the member is M.sub.1, and a mass-based content of the surfactant in a position 10 nm below the surface in a thickness direction of the member is M.sub.2, M.sub.1/M.sub.2 is 0.50 to 0.90, and an atom number ratio X.sub.1 of the number of fluorine atoms contained in the surface to the number of carbon atoms contained in the surface is 0.50 to 3.0.

A member contains a fluorine-containing polymer and a fluorine-containing surfactant, in which provided that a mass-based content of the fluorine-containing surfactant in at least a surface of a portion of the member is M.sub.1, and a mass-based content of the surfactant in a position 10 nm below the surface in a thickness direction of the member is M.sub.2, M.sub.1/M.sub.2 is 0.50 to 0.90, and an atom number ratio X.sub.1 of the number of fluorine atoms contained in the surface to the number of carbon atoms contained in the surface is 0.50 to 3.0.

In a first aspect, a transparent fluoropolymer film includes, a vinyl fluoride polymer, 2 to 8 wt % of an acrylate polymer, and 0.1 to 4 wt % of a triazine UV absorber. After heating at 100 C. for 96 hours, the transparent fluoropolymer film has a 340 nm absorbance of at least 1.5. In a second aspect, a transparent multilayer film includes a polymeric substrate film and a fluoropolymer film. The fluoropolymer film includes a vinyl fluoride polymer, 2 to 8 wt % of an acrylate polymer and 0.1 to 4 wt % of a triazine UV absorber. After heating at 100 C. for 96 hours, the transparent fluoropolymer film has a 340 nm absorbance of at least 1.5.

In a first aspect, a transparent fluoropolymer film includes, a vinyl fluoride polymer, 2 to 8 wt % of an acrylate polymer, and 0.1 to 4 wt % of a triazine UV absorber. After heating at 100 C. for 96 hours, the transparent fluoropolymer film has a 340 nm absorbance of at least 1.5. In a second aspect, a transparent multilayer film includes a polymeric substrate film and a fluoropolymer film. The fluoropolymer film includes a vinyl fluoride polymer, 2 to 8 wt % of an acrylate polymer and 0.1 to 4 wt % of a triazine UV absorber. After heating at 100 C. for 96 hours, the transparent fluoropolymer film has a 340 nm absorbance of at least 1.5.

In a first aspect, a transparent fluoropolymer film includes, a vinyl fluoride polymer, 2 to 8 wt % of an acrylate polymer, and 0.1 to 4 wt % of a triazine UV absorber. After heating at 100 C. for 96 hours, the transparent fluoropolymer film has a 340 nm absorbance of at least 1.5. In a second aspect, a transparent multilayer film includes a polymeric substrate film and a fluoropolymer film. The fluoropolymer film includes a vinyl fluoride polymer, 2 to 8 wt % of an acrylate polymer and 0.1 to 4 wt % of a triazine UV absorber. After heating at 100 C. for 96 hours, the transparent fluoropolymer film has a 340 nm absorbance of at least 1.5.

Provided is a melt processible fluororesin molded article with reduced metal ions after molding (eluted metal ions) and submicron size fine particles. The melt processible fluororesin molded article has an amount of eluted Ni ions (in pg/cm.sup.2) and amount of eluted Cr ions (in pg/cm.sup.2) and amount of eluted Mo ions (in pg/cm.sup.2) in a test solution after eluting for 20 hours at 60? C. using 12% nitric acid, quantitatively analyzed by the ICP (induced coupled plasma) mass analysis method, satisfy the following formula:
0.5?1?[(M.sub.1+M.sub.2)/(M.sub.1+M.sub.2+M.sub.3)]<1, wherein M.sub.1 refers to the eluted Cr ion amount (in pg/cm.sup.2), M.sub.2 refers to the eluted Mo ion amount (in pg/cm.sup.2), and M.sub.3 refers to the eluted Ni ion amount (in pg/cm.sup.2).

Provided is a melt processible fluororesin molded article with reduced metal ions after molding (eluted metal ions) and submicron size fine particles. The melt processible fluororesin molded article has an amount of eluted Ni ions (in pg/cm.sup.2) and amount of eluted Cr ions (in pg/cm.sup.2) and amount of eluted Mo ions (in pg/cm.sup.2) in a test solution after eluting for 20 hours at 60? C. using 12% nitric acid, quantitatively analyzed by the ICP (induced coupled plasma) mass analysis method, satisfy the following formula:
0.5?1?[(M.sub.1+M.sub.2)/(M.sub.1+M.sub.2+M.sub.3)]<1, wherein M.sub.1 refers to the eluted Cr ion amount (in pg/cm.sup.2), M.sub.2 refers to the eluted Mo ion amount (in pg/cm.sup.2), and M.sub.3 refers to the eluted Ni ion amount (in pg/cm.sup.2).

A curable composition capable of being cured at a low temperature of from room temperature to 150 C. is provided. The curable composition comprises a fluorinated polymer containing at least three functional groups represented by the following formula (F) and at least one curing agent selected from the group consisting of an isocyanate-type curing agent, a blocked isocyanate-type curing agent and an amino resin-type curing agent:

R.sup.f1COZ.sup.1 (F) (in the formula (1), R.sup.f1 is a fluoroalkylene group, or a fluoroalkylene group with at least two carbon atoms having an etheric oxygen atom between carbon-carbon atoms, Z.sup.1 is NR.sup.1NR.sup.2H or NR.sup.3OR.sup.4, and R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently a hydrogen atom or an alkyl group.)

A curable composition capable of being cured at a low temperature of from room temperature to 150 C. is provided. The curable composition comprises a fluorinated polymer containing at least three functional groups represented by the following formula (F) and at least one curing agent selected from the group consisting of an isocyanate-type curing agent, a blocked isocyanate-type curing agent and an amino resin-type curing agent:

R.sup.f1COZ.sup.1 (F) (in the formula (1), R.sup.f1 is a fluoroalkylene group, or a fluoroalkylene group with at least two carbon atoms having an etheric oxygen atom between carbon-carbon atoms, Z.sup.1 is NR.sup.1NR.sup.2H or NR.sup.3OR.sup.4, and R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently a hydrogen atom or an alkyl group.)