Based on the search results, here is the information about eyeliner:

Ingredients or materials

• Eyeliners contain the same basic kinds of ingredients: film formers, thickeners, and pigments. Film formers deposit a thin layer on your skin. Thickeners -- such as waxes, natural gums, and clays -- help stabilize the formula so it will stick to your lids. Pigments include iron oxides to create blacks and browns, ultramarine for blue, chromium oxide for green, and titanium dioxide for white.
• Some eyeliner ingredients can cause major irritation and even more severe long-term effects to your health. The 5 most common ingredients found in eyeliner that you should avoid are formaldehyde, parabens, carnauba wax, lead, and phthalates.

Positive

• Liquid liners can be the easiest to handle and can create a clean line. Creams and gels require a brush and are also fairly goof-proof because they can be smudged for a smoky look or applied in a heavy, dramatic line.

Negative

• Some eyeliner ingredients can cause major irritation and even more severe long-term effects to your health. The 5 most common ingredients found in eyeliner that you should avoid are formaldehyde, parabens, carnauba wax, lead, and phthalates.

In summary, eyeliner ingredients include film formers, thickeners, and pigments. Liquid liners can be the easiest to handle and can create a clean line. However, some eyeliner ingredients can cause major irritation and even more severe long-term effects to your health, so it is important to avoid them.