WE CLAIM:
1. An on-press development type lithographic printing plate precursor comprising:
an image recording layer on a support,
wherein the lithographic printing plate precursor has projections which are discontinuously formed on a surface of an outermost layer on a side where the image recording layer is provided, and
a melting point of each projection is in a range of 70°C to 150°C.
2. The on-press development type lithographic printing plate precursor according to claim 1,
wherein an average dimension of the projections in a surface direction of the outermost layer is in a range of 0.1 urn to 45 urn.
3. The on-press development type lithographic printing plate precursor according to claim 1
or2,
wherein an average dimension of the projections in a surface direction of the outermost layer is greater than 0.7 urn and less than or equal to 30 urn.
4. The on-press development type lithographic printing plate precursor according to any one
of claims 1 to 3,
wherein an occupation area ratio of the projections in the surface of the outermost layer is 20% by area or less.
5. The on-press development type lithographic printing plate precursor according to any one
of claims 1 to 4,
wherein an occupation area ratio of the projections in the surface of the outermost layer is in a range of 0.5% by area to 20% by area.
6. The on-press development type lithographic printing plate precursor according to any one
of claims 1 to 5,
wherein each projection contains at least one resin selected from the group consisting of polyethylene and modified polyethylene.
7. The on-press development type lithographic printing plate precursor according to any one

of claims 1 to 6,
wherein each projection contains 80% by mass or greater of at least one resin selected from the group consisting of polyethylene and modified polyethylene.
8. Amethod of producing a lithographic printing plate, comprising:
a step of image-wise exposing the on-press development type lithographic printing plate precursor according to any one of claims 1 to 7 to form an exposed portion and an unexposed portion; and
a step of supplying at least one of printing ink or dampening water to remove a non-image portion.