Liquid-crystalline medium

A liquid-crystalline medium having a positive dielectric anisotropy, comprising one or more compounds of Formula I

• in which
• R1 and R2 each, independently of one another, denote an alkyl or alkoxy group having 1 to 12 C atoms or an alkenyl or alkenyloxy group having 2 to 12 C atoms, in which one or more non-adjacent CH2 groups are optionally substituted by —C≡C—, —CF2O—, —OCF2—, —CH═CH—,
• or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms are optionally replaced by a halogen atom or a cycloalkyl, cycloalkenyl, or a cycloalkoxy group having 3 to 12 C atoms, in which one or more H atoms are optionally replaced by a halogen atom;
• R3 denotes a H atom, an alkyl group having 1 to 3 C atoms, or an alkenyl group having 2 to 3 C atoms, in which one or more non-adjacent CH2 groups are optionally substituted by —C≡C—, —CF2O—, —OCF2—, —CH═CH—, —O—, —CO—O—, or —O—CO— in such a way that O atoms are not linked directly to one another, preferably H or CH3;
• L1 and L2 each, independently of one another, denote F, Cl, CF3, or CHF2, preferably L1 and L2 both denote F;
• and
• one or more compounds selected from the group consisting of compounds of Formulae P, S and B:
• on each appearance, independently of one another, are
• R0 denotes an alkyl or alkoxy group having 1 to 12 C atoms or an alkenyl or alkenyloxy group having 2 to 12 C atoms, in which one or more non-adjacent CH2 groups are optionally substituted by —C≡C—, —CF2O—, —OCF2—, —CH═CH—,
• —O—, —CO—O—, or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms are optionally replaced by a halogen atom or a cycloalkyl, cycloalkenyl, or cycloalkoxy group having 3 to 12 C atoms, in which one or more H atoms are optionally replaced by a halogen atom;
• L1 and L2 independently of one another, denote H or F, preferably L2 denotes F;
• Y0 denotes a H atom, an alkyl group having 1 to 3 C atoms or an alkenyl group having 2 to 3 C atoms, in which one or more non-adjacent CH2 groups are optionally substituted by —C≡C—, —CF2O—, —OCF2—, —CH═CH—, —O—, —CO—O—, or —O—CO— in such a way that O atoms are not linked directly to one another, preferably H or CH3;
• X0 denotes halogen, a halogenated alkyl or alkoxy having 1 to 6 C atoms, or a halogenated alkenyl or alkenyloxy having 2 or 6 C atoms, F, Cl, —OCF3, —OCHF2, —O—CH2CF3, —O—CH═CF2, —O—CH═CH2 or —CF3, very preferably F, —CF3, —CHF2, —OCHF2 or —OCF3;
• Z3 denotes —CH2CH2—, —CF2CF2—, —COO—, —OCO—, trans-CH═CH—, trans-CF═CF—, —CH2O—, —OCH2—, or a single bond, preferably —CH2CH2—, —COO—, trans-CH═CH— or a single bond and very preferably —COO—, trans-CH═CH— or a single bond;
• and
• n denotes 0, 1, 2, or 3, preferably 1, 2 or 3 and particularly preferably 1;
• denotes one of
• R1 and R2 each, independently of one another, denote a H atom, a halogen atom, an alkyl or alkoxy group having 1 to 12 C atoms, or an alkenyl or alkenyloxy group having 2 to 12 C atoms, in which one or more non-adjacent CH2 groups are optionally substituted by —C≡C—, —CF2O—, —OCF2—, —CH═CH—,
• —O—, —CO—O—, or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms are optionally replaced by a halogen atom or a cycloalkyl or cycloalkoxy group having 3 to 12 C atoms, in which one or more H atoms are optionally replaced by a halogen atom;
• L1 to L4 each, independently of one another, denote H, F, or Cl;
• Y1 to Y3 each, independently of one another, denote a H atom, an alkyl group having 1 to 3 C atoms, or an alkenyl group having 2 to 3 C atoms, in which one or more non-adjacent CH2 groups are optionally substituted by —C≡C—, —CF2O—, —OCF2—, —CH═CH—, —O—, —CO—O—, or —O—CO— in such a way that O atoms are not linked directly to one another, preferably H or CH3;
• Z1 denotes —CF2O—, —OCF2—, —CH2O—, —OCH2—, —CO—O—, —O—CO—, —C2H4—, —C2F4—, —CF2CH2—, —CH2CF2—, —CFHCFH—, —CFHCH2—, —CH2CFH—, —CF2CFH—, —CFHCF2—, —CH═CH—, —CF═CH—, —CH═CF—, —CF═CF—, —C≡C—, or a single bond;
• k denotes 0, 1, 2, or 3;
• denotes one of
• R21 denotes an alkyl or an alkoxy group having 1 to 12 C atoms or an alkenyl or an alkenyloxy group having 2 to 12 C atoms, in which one or more non-adjacent CH2 groups are optionally substituted by —C≡C—, —CF2O—, —OCF2—, —CH═CH—,
• —O—, —CO—O—, or —O—CO— in such a way that 0 atoms are not linked directly to one another, and in which one or more H atoms are optionally replaced by a halogen atom or a cycloalkyl or a cycloalkoxy group having 3 to 12 C atoms, in which one or more H atoms are optionally replaced by a halogen atom;
• X3 denotes halogen, a halogenated alkyl or alkoxy having 1 to 3 C atoms, or a halogenated alkenyl or alkenyloxy having 2 or 3 C atoms, F, Cl, —OCF3, —OCHF2, —O—CH2CF3, —O-CH═CF2, —O-CH═CH2 or —OF3, very preferably F, Cl, —O—CH═CF2, —OCHF2 or —OCF3;
• L1 and L2 each, independently of one another, denote F, Cl, CF3, or CHF2;
• L3 and L4 each, independently of one another, denote H or F;
• Z denotes a single bond, —CH2CH2—, —CH═CH—, —CF2O—, —OCF2—, —CH2O—, —OCH2—, —COO—, —OCO—, —C2F4—, —CF═CF—, or —CH═CHCH2O;
• Y denotes S, O, CH2, CH2CH2, CH2O, OCH2, or CH═CH;
• and
• I denotes 0 or 1.